bluuebunny/crossref_metadata_2025 huggingface dataset:
Label Transfer Reagents to Probe p38 MAPK Binding Partners
Authors: Andrews Simeon S. , Hill Zachary B. , Perera B. Gayani K. , Maly Dustin J.
Published: January 2013

Protein kinases are essential enzymes for cellular signaling, and are often regulated by participation in protein complexes. The mitogen‐activated protein kinase (MAPK) p38 is involved in multiple pathways, and its regulation depends on its interactions with other signaling proteins. However, the identification of p38‐interacting proteins is challenging. For this reason, we have developed label transfer reagents (LTRs) that allow labeling of p38 signaling complexes. These LTRs leverage the potency and selectivity of known p38 inhibitors to place a photo‐crosslinker and tag in the vicinity of p38 and its binding partners. Upon UV irradiation, proteins that are in close proximity to p38 are covalently crosslinked, and labeled proteins are detected and/or purified with an orthogonal chemical handle. Here we demonstrate that p38‐selective LTRs selectively label a diversity of p38 binding partners, including substrates, activators, and inactivators. Furthermore, these LTRs can be used in immunoprecipitations to provide low‐resolution structural information on p38‐containing complexes.
Synthesis of Specially Designed Probes to Broaden Transketolase Scope
Authors: Simon G. , Eljezi T. , Legeret B. , Charmantray F. , Castillo J. A. , Guérard‐Hélaine C. , Lemaire M. , Bouzon M. , Marlière P. , Hélaine V. , Hecquet L.
Published: January 2013

Efficient, biocompatible, stereospecific strategies were developed to prepare eight probes to assay transketolase (TK) variants with new substrate specificities. The structure of these probes combines a sugar moiety (D‐threo or L‐erythro ketose, or D‐threo aldose) with the side chain of an amino acid (Ala, Leu, Val, Met, Thr) for in vivo detection of new TK activities using amino acid auxotrophs. To obtain D‐threo ketose probes, biocatalysts, such as transketolase and fructose‐6‐phosphate aldolase Ala129Ser, were used whereas L‐erythro ketoses and D‐threo aldose probes were synthesized by the way of organocatalysis or Sharpless dihydroxylation as sustainable alternative key steps to biocatalysis.
Long‐Lived Charge Separation in Novel Axial Donor–Porphyrin–Acceptor Triads Based on Tetrathiafulvalene, Aluminum(III) Porphyrin and Naphthalenediimide
Authors: Poddutoori Prashanth K. , Zarrabi Niloofar , Moiseev Andrey G. , Gumbau‐Brisa Roger , Vassiliev Serguei , van der Est Art
Published: January 2013

Two self‐assembled supramolecular donor–acceptor triads consisting of AlIII porphyrin (AlPor) with axially bound naphthalenediimide (NDI) as an acceptor and tetrathiafulvalene (TTF) as a secondary donor are reported. In the triads, the NDI and TTF units are attached to AlIII on opposite faces of the porphyrin, through covalent and coordination bonds, respectively. Fluorescence studies show that the lowest excited singlet state of the porphyrin is quenched through electron transfer to NDI and hole transfer to TTF. In dichloromethane hole transfer to TTF dominates, whereas in benzonitrile (BN) electron transfer to NDI is the main quenching pathway. In the nematic phase of the liquid crystalline solvent 4‐(n‐pentyl)‐4′‐cyanobiphenyl (5CB), a spin‐polarized transient EPR spectrum that is readily assigned to the weakly coupled radical pair TTF.+NDI.− is obtained. The initial polarization pattern indicates that the charge separation occurs through the singlet channel and that singlet–triplet mixing occurs in the primary radical pair. At later time the polarization pattern inverts as a result of depopulation of the states with singlet character by recombination to the ground state. The singlet lifetime of TTF.+NDI.− is estimated to be 200–300 ns, whereas the triplet lifetime in the approximately 350 mT magnetic field of the X‐band EPR spectrometer is about 10 μs. In contrast, in dichloromethane and BN the lifetime of the charge separation is <10 ns.
Highly Efficient Diglycolamide‐Based Task‐Specific Ionic Liquids: Synthesis, Unusual Extraction Behaviour, Irradiation, and Fluorescence Studies
Authors: Mohapatra Prasanta K. , Sengupta Arijit , Iqbal Mudassir , Huskens Jurriaan , Verboom Willem
Published: January 2013

Two new diglycolamide‐based task‐specific ionic liquids (DGATSILs) were evaluated for the extraction of actinides and lanthanides from acidic feed solutions. These DGATSILs were capable of exceptionally high extraction of trivalent actinide ions, such as Am3+, and even higher extraction of the lanthanide ion, Eu3+ (about 5–10 fold). Dilution of the DGATSILs in an ionic liquid, C4mim+⋅NTf2−, afforded reasonably high extraction ability, faster mass transfer, and more efficient stripping of the metal ion. The nature of the extracted species was studied by slope analysis, which showed that the extracted species contained one NO3− anion, along with the participation of two DGATSIL molecules. Time‐resolved laser fluorescence spectroscopy (TRLFS) analysis showed a strong complexation with no inner‐sphere water molecule in the EuIIIDGATSIL complexes in the presence and absence of C4mim+⋅NTf2− as the diluent. The very high radiolytic stability of DGATSIL 6 makes it one of the most‐efficient solvent systems for the extraction of actinides under acidic feed conditions.
Structural Insights into the Trp‐Cage Folding Intermediate Formation
Authors: Rovó Petra , Stráner Pál , Láng András , Bartha István , Huszár Kristóf , Nyitray László , Perczel András
Published: January 2013

The 20 residue long Trp‐cage is the smallest protein known, and thus has been the subject of several in vitro and in silico folding studies. Here, we report the multistate folding scenario of the miniprotein in atomic detail. We detected and characterized different intermediate states by temperature dependent NMR measurements of the 15N and 13C/15N labeled protein, both at neutral and acidic pH values. We developed a deconvolution technique to characterize the invisible—fully folded, unfolded and intermediate—fast exchanging states. Using nonlinear fitting methods we can obtain both the thermodynamic parameters (ΔHF–I, TmF–I, ΔCpF–I and ΔHI–U, TmI–U, ΔCpI–U) and the NMR chemical shifts of the conformers of the multistate unfolding process. During the unfolding of Trp‐cage distinct intermediates evolve: a fast‐exchanging intermediate is present under neutral conditions, whereas a slow‐exchanging intermediate‐pair emerges at acidic pH. The fast‐exchanging intermediate has a native‐like structure with a short α‐helix in the G11–G15 segment, whereas the slow‐exchanging intermediate‐pair presents elevated dynamics, with no detectable native‐like residue contacts in which the G11P12 peptide bond has either cis or trans conformation. Heteronuclear relaxation studies combined with MD simulations revealed the source of backbone mobility and the nature of structural rearrangements during these transitions. The ability to detect structural and dynamic information about folding intermediates in vitro provides an excellent opportunity to gain new insights into the energetic aspects of the energy landscape of protein folding. Our new experimental data offer exceptional testing ground for further computational simulations.
Biomembrane Interactions of Functionalized Cryptophane‐A: Combined Fluorescence and 129Xe NMR Studies of a Bimodal Contrast Agent
Authors: Sloniec Jagoda , Schnurr Matthias , Witte Christopher , Resch‐Genger Ute , Schröder Leif , Hennig Andreas
Published: January 2013

Fluorescent derivatives of the 129Xe NMR contrast agent cryptophane‐A were obtained by functionalization with near infrared fluorescent dyes DY680 and DY682. The resulting conjugates were spectrally characterized, and their interaction with giant and large unilamellar vesicles of varying phospholipid composition was analyzed by fluorescence and NMR spectroscopy. In the latter, a chemical exchange saturation transfer with hyperpolarized 129Xe (Hyper‐CEST) was used to obtain sufficient sensitivity. To determine the partitioning coefficients, we developed a method based on fluorescence resonance energy transfer from Nile Red to the membrane‐bound conjugates. This indicated that not only the hydrophobicity of the conjugates, but also the phospholipid composition, largely determines the membrane incorporation. Thereby, partitioning into the liquid‐crystalline phase of 1,2‐dipalmitoyl‐sn‐glycero‐3‐phosphocholine was most efficient. Fluorescence depth quenching and flip‐flop assays suggest a perpendicular orientation of the conjugates to the membrane surface with negligible transversal diffusion, and that the fluorescent dyes reside in the interfacial area. The results serve as a basis to differentiate biomembranes by analyzing the Hyper‐CEST signatures that are related to membrane fluidity, and pave the way for dissecting different contributions to the Hyper‐CEST signal.
Urea Hydrolysis for the Selective Catalytic Reduction of NOx: Comparison of Liquid‐ and Gas Phase Decomposition
Authors: Peitz Daniel , Bernhard Andreas M. , Mehring Max , Elsener Martin , Kröcher Oliver
Published: January 2013

Zur Reduzierung der Stickoxid‐Konzentration in Autoabgasen wird meist die selektive katalytische Reduktion mit Ammoniak verwendet. Um jedoch das Mitführen von Ammoniak in Kraftfahrzeugen zu vermeiden, wird auf Harnstoff als NH3‐Vorläufer zurückgegriffen. Zur kontrollierten Harnstoffzersetzung bereits vor dem Eindüsen in den Abgasstrang bietet sich der Einsatz eines separaten Reaktors an. Die Harnstoffzersetzung zu Ammoniak in der Flüssigphase unter Druck in einem beheizten Reaktor wurde mit der Zersetzung in der Gasphase verglichen. Hierbei wurden in der Flüssigphase weit höhere Umsatzraten pro Reaktorvolumen erreicht. Katalysatoren, die in der Gasphase eine hohe Aktivität zeigten, hatten nur einen kleinen Einfluss auf die Flüssigphasenzersetzung.
Removal of Aromatic Volatile Organic Compounds in the Sequencing Batch Reactor of Petroleum Refinery Wastewater Treatment Plant
Authors: Cheng Hsin‐Han , Hsieh Chu‐Chin
Published: January 2013

This paper presents a field investigation of aromatic volatile organic compounds (AVOCs) emissions from a sequence batch reactor (SBR) with powdered activated carbon (PAC) to treat the wastewater in a large petroleum refinery plant. AVOC with high Henry's constant preferred to transfer from liquid‐phase into air‐phase so that might cause the emission and odor problem. During SBR operation, AVOC concentrations and distributions in wastewater, sludge and off‐gas were analyzed. The total AVOC removal from wastewater was >99% under the kinetic parameters of SBR operated. Batch experiments were carried out in the laboratory to obtain the adsorptive characteristic of AVOC onto PAC, but the results showed that bio‐degradation was the main removal mechanism (85%). Nevertheless, off‐gas emission (<1%) and AVOC in the sludge (<0.1%) remained a stable level. Oxidation/reduction potential (ORP) was correlated to the logarithm of the dissolved oxygen (DO) concentration in a linear relationship so that ORP profile could indirectly reflect the DO and biomass concentrations. Since the influent AVOC concentration was varied and difficultly to measure, ORP could be used as real‐time parameter for optimizing SBR operation. The results provided useful information for future evaluation of AVOC emissions from wastewater treatment plants.
Pesticide Health Risk Mapping and Sensitivity Analysis of Parameters in Groundwater Vulnerability Assessment
Authors: Akbar Tahir Ali , Akbar Raza Ali
Published: January 2013

The extensive use of pesticides for increasing the agricultural production is affecting the quality of groundwater. The objectives of this article are to (i) develop pesticide relative leaching ranks for well sites, (ii) develop maps for human health risks due to pesticide applications, and (iii) identify the most significant parameters in pesticide simulations for groundwater vulnerability assessment. The methods include (i) development of acifluorfen relative leaching ranks for 25 well sites using ArcPRZM‐3, (ii) development of health risk maps using model simulated maximum dissolved bentazon concentrations on the basis of USA drinking water quality guidelines, (iii) sensitivity analysis for 14 ArcPRZM‐3 input parameters using the Plackett–Burman method. ArcPRZM‐3 is a user‐friendly system for spatial modeling of pesticide leaching from surface to groundwater. Thirteen acifluorfen relative leaching potential ranks were developed in which the pesticide leaching decrease from 1 to 13. The model predicted ranks for well 34 and well 9 were 2nd and 3rd, respectively, and acifluorfen was detected in both wells during the physical monitoring. The percentages of high health risks in the agricultural areas were 48.38 and 72.72% for Randolph and Independence Counties, respectively. The most significant parameters were thickness of horizon compartment, runoff curve number of antecedent moisture condition II for cropping, soil bulk density, and total application of pesticide. The irrigation, soil permeability, and numerical dispersion could impact the pesticide leaching in soils toward groundwater. The ArcPRZM‐3 system could be efficiently applied for spatial modeling and mapping of pesticide concentrations for groundwater vulnerability assessment on a large scale.
Electro‐Fenton Treatment of Photographic Processing Wastewater
Authors: Bensalah Nasr , Bedoui Ahmed , Chellam Shankararaman , Abdel‐Wahab Ahmed
Published: January 2013

In this work, the treatment of photographic processing wastewaters (PPW) by electro‐Fenton process has been investigated. The Influence of operating conditions on kinetics and efficiency of electro‐Fenton process has been evaluated using carbon felt cathode and platinium (Pt) or boron‐doped diamond (BDD) anode. The results of electro‐Fenton treatment of PPW have shown that nearly complete removal of total phenols was obtained for all combinations with pseudo‐first rate constants of 0.07, 0.012, and 0.018/min for carbon felt/Pt, carbon felt/BDD and Pt/BDD cathode/anode combinations, respectively. The combination of carbon felt cathode with BDD anode achieved the highest total organic carbon (TOC) removal of 90%, while it did not exeed 40% for carbon felt/Pt combination. Increasing current intensity and Fe2+ dose enhances the efficiency of electro‐Fenton process. However, increasing pH decreases TOC removal during the treatment of PPW by electro‐Fenton process. The highest efficiency of electro‐Fenton process using BDD anode can be explained by the contribution of direct and indirect oxidation routes in the degradation mechanism of organics including (i) oxidation via hydroxyl radicals generated from the catalytic decomposition of H2O2 and from water discharge on BDD anode, (ii) direct oxidation of certain organic compounds on BDD anode, and (iii) mediated oxidation with inorganic oxidants electrogenerated from anodic oxidation of supporting salts.
The biomechanics of the human tongue
Authors: Kajee Yaseen , Pelteret J‐P. V. , Reddy B. D.
Published: January 2013

The human tongue is composed mainly of skeletal muscle tissue and has a complex architecture. Its anatomy is characterised by interweaving yet distinct muscle groups. It is a significant contributor to the phenomenon of obstructive sleep apnoea syndrome. A realistic model of the tongue and computational simulations are important in areas such as linguistics and speech therapy. The aim of this work is to report on the construction of a geometric and constitutive model of the human tongue and to demonstrate its use in computational simulations for obstructive sleep apnoea syndrome research. The geometry of the tongue and each muscle group of the tongue, including muscle fibre orientations, are captured from the Visible Human Project dataset. The fully linear muscle model is based on the Hill three‐element model that represents the constituent parts of muscle fibres. The mechanics of the model are limited to quasi‐static, small‐strain, linear‐elastic behaviour. The main focus of this work is on the material directionality and muscle activation. The transversely isotropic behaviour of the muscle tissue is accounted for, as well as the influence of muscle activation. The behaviour of the model is illustrated in a number of benchmark tests and for the case of a subject in the supine position. Copyright © 2013 John Wiley & Sons, Ltd.
Preparation of Fluorescent Tubulin Binders
Authors: Riva Elena , Mattarella Martin , Borrelli Stella , Christodoulou Michael S. , Cartelli Daniele , Main Marcus , Faulkner Stephen , Sykes Daniel , Cappelletti Graziella , Snaith John S. , Passarella Daniele
Published: January 2013

Thiocolchicine, taxol and cephalomannine have been used as building blocks for the preparation of four different fluorescent compounds designed to image the tubulin/microtubule network in cells. Thiocolchicine gave the best results and, in particular, the compound derived from conjugation with fluorescein minimally inhibits tubulin polymerization, is cell permeable and binds microtubules. Thus, it meets some of the demanding requirements for a new fluorescent dye that can secure a direct assay to evidence the tubulin/microtubules network in cells.
Characterization and modeling of video popularity
Authors: Li J. , Ma S.
Published: January 2013

Popularity of videos is a key factor for the design and management of a streaming media system. In this paper, three factors representing clients’ access to a media system are investigated to characterize popularity. One of the factors is the commonly used access frequency. Numerical studies on one of the workloads from a video‐on‐demand system in the University of Science and Technology of China are also given. The results show that the commonly used Zipf‐like model is not suitable to characterize popularity distribution. However, the stretched exponential model is better, and the shape of the stretched exponential distribution of popularity is related to the characterization of popularity and the duration of workload. The rank correlation between the access frequency and the other two factors is further studied. It is concluded that the rank of video popularity and the ability of each characterization to distinguish video popularity are different, which implies that the combinative use of different characterizations can increase the distinction of video popularity.Copyright © 2013 John Wiley & Sons, Ltd.
Efficient and flexible password authenticated key agreement for Voice over Internet Protocol Session Initiation Protocol using smart card
Authors: Zhang Liping , Tang Shanyu , Cai Zhihua
Published: January 2013

Providing a suitable key agreement protocol for session initiation protocol is crucial to protecting the communication among the users over the open channel. This paper presents an efficient and flexible password authenticated key agreement protocol for session initiation protocol associated with Voice over Internet Protocol. The proposed protocol has many unique properties, such as session key agreement, mutual authentication, password updating function and the server not needing to maintain a password or verification table, and so on. In addition, our protocol is secure against the replay attack, the impersonation attack, the stolen‐verifier attack, the man‐in‐the‐middle attack, the Denning–Sacco attack, and the offline dictionary attack with or without the smart card. Copyright © 2013 John Wiley & Sons, Ltd.
Human antibodies reactive to NeuGcGM3 ganglioside have cytotoxic antitumor properties
Authors: Rodríguez‐Zhurbenko Nely , Martínez Darel , Blanco Rancés , Rondón Teresa , Griñán Tania , Hernández Ana María
Published: January 2013

N‐glycolylated gangliosides are not naturally expressed in healthy human tissues but are overexpressed in several tumors. We demonstrate the existence of antibodies that bind (N‐glycolylneuraminyl)‐lactosylceramide (NeuGcGM3) and are detectable in the sera of 65 from the 100 donors (65%) tested by ELISA. From those 65 NeuGcGM3 antibody‐positive donors, 35 had antibodies that were able to recognize and kill NeuGcGM3‐expressing tumor cells by a complement‐mediated mechanism. After complement inactivation, 11 of the 35 positive sera showed a direct cytotoxic effect on the tumor cells. This complement‐independent cytotoxicity was dependent on the presence of antigen on the membrane and resembles an oncotic necrosis cell death. Both the levels of anti‐NeuGcGM3 antibodies in the sera as well as the percentage of healthy donors with this immunity decreased with the age of the donor. In contrast to age and gender‐matched healthy donors, we could only detect low reactivity against NeuGcGM3 in the sera of six out of 53 non‐small cell lung cancer patients. These results suggest the existence of antibodies against NeuGcGM3 with antitumor immune surveillance functions, reinforcing the importance of N‐glycolylated gangliosides as antitumor targets.
Salmonella polarises peptide‐MHC‐II presentation towards an unconventional Type B CD4+T‐cell response
Authors: Jackson Nicola P. , Kang Yu Hui , Lapaque Nicolas , Janssen Hans , Trowsdale John , Kelly Adrian P.
Published: January 2013

Distinct peptide‐MHC‐II complexes, recognised by Type A and B CD4+ T‐cell subsets, are generated when antigen is loaded in different intracellular compartments. Conventional Type A T cells recognize their peptide epitope regardless of the route of processing, whereas unconventional Type B T cells only recognise exogenously supplied peptide. Type B T cells are implicated in autoimmune conditions and may break tolerance by escaping negative selection. Here we show that Salmonella differentially influences presentation of antigen to Type A and B T cells. Infection of bone marrow‐derived dendritic cells (BMDCs) with Salmonella enterica serovar Typhimurium (S. Typhimurium) reduced presentation of antigen to Type A T cells but enhanced presentation of exogenous peptide to Type B T cells. Exposure to S. Typhimurium was sufficient to enhance Type B T‐cell activation. Salmonella Typhimurium infection reduced surface expression of MHC‐II, by an invariant chain‐independent trafficking mechanism, resulting in accumulation of MHC‐II in multi‐vesicular bodies. Reduced MHC‐II surface expression in S. Typhimurium‐infected BMDCs correlated with reduced antigen presentation to Type A T cells. Salmonella infection is implicated in reactive arthritis. Therefore, polarisation of antigen presentation towards a Type B response by Salmonella may be a predisposing factor in autoimmune conditions such as reactive arthritis.
Two Mononuclear Iron(II) Spin‐Crossover Complexes with a N4O2 Coordination Sphere
Authors: Zhang Li , Xu Guan‐Cheng , Wang Zhe‐Ming , Gao Song
Published: January 2013

Two mononuclear spin‐crossover compounds Fe(L1)2 (1) and Fe(L2)2 (2) {HL1 = 2‐hydroxy‐3‐methyl‐N′‐[1‐(pyridine‐2‐yl)butylidene]benzohydrazide, HL2 = 2‐hydroxy‐N′‐[1‐(pyridine‐2‐yl)butylidene]benzohydrazide} were successfully synthesized. The magnetic measurements of the compounds revealed different thermal magnetic behavior. Compound 1 undergoes a gradual complete thermal spin crossover (SCO) with T1/2↑/↓ = 243/240 K and a hysteresis loop of 3 K. Compound 2 shows a gradual incomplete SCO during the measurable temperature region with T1/2 ≈ 330 K. Through the comparison of the magnetic and structural results for 1 and 2 with previously reported related compounds, the alkyl substitutions of the ligand were considered to affect the ligand‐field strength and hydrogen‐bonding interactions. In addition, photomagnetism results showed an 87 % photoconversion and 36 K of T(LIESST) (LIESST = light‐induced excited spin‐state trapping) for compound 1. The results enrich the knowledge on how to control the spin‐crossover behavior in the new system.
Cationic and Neutral (Ar‐BIAN)Copper(I) Complexes Containing Phosphane and Arsane Ancillary Ligands: Synthesis, Molecular Structure and Catalytic Behaviour in Cycloaddition Reactions of Azides and Alkynes
Authors: Li Lidong , Lopes Patrícia S. , Figueira Cláudia A. , Gomes Clara S. B. , Duarte M. Teresa , Rosa Vitor , Fliedel Christophe , Avilés Teresa , Gomes Pedro T.
Published: January 2013

A series of new cationic and neutral (Ar‐BIAN)copper(I) complexes [in which Ar‐BIAN = bis(aryl)acenaphthenequinonediimine] was synthesised and characterised by elemental analysis, 1D and 2D NMR spectroscopy and single‐crystal X‐ray diffraction. The cationic complexes of the general formula [Cu(Ar‐BIAN)L2]BF4 [L2 = (PPh3)2 (1), dppe (2), dppf (3), (AsPh3)2 (4); Ar = 4‐iPrC6H4 (a), 4‐MeOC6H4 (b), 4‐NO2C6H4 (c), 2‐iPrC6H4 (d), Ph2PCH2CH2PPh2 (dppe), (Ph2PC5H4)2Fe (dppf)] were synthesised by reaction of [Cu(EPh3)4]BF4 (E = P or As) and equimolar amounts of Ar‐BIAN ligands, or by reaction of equimolar amounts of [Cu(NCMe)4]BF4, 4‐iPrC6H4‐BIAN (a) and diphosphanes dppe or dppf, in dichloromethane, whereas the neutral complexes of the types [CuX(Ar‐BIAN)(EPh3)] [X = Cl, E = P (5); X = I, E = P (6); X = Cl, E = As (9)] and [{CuX(Ar‐BIAN)}2] [X = Cl (7), I (8); Ar = a, b, c, d, 2,4,6‐Me3C6H2 (e), 2,6‐iPr2C6H3 (f)] were prepared by reaction of CuCl or CuI with equimolar amounts of Ar‐BIAN and EPh3 (E = P, As or Sb) in acetonitrile under reflux conditions. The type of ancillary ligand EPh3 and the aryl substituents on Ar‐BIAN play crucial roles in determining the formation of cationic or neutral copper(I) complexes. No copper(I) complexes containing coordinated SbPh3 were isolated; all the corresponding attempts led to dimeric complexes 7 or 8. Most of the complexes crystallised easily. Their study by X‐ray diffraction revealed distorted‐tetrahedral geometries around the copper(I) centres, which are quite influenced by the various aryl substituents on Ar‐BIAN and the ancillary ligands EPh3. All complexes 1–9 except cationic dppf derivative 3a are active catalysts for cycloaddition reactions of alkynes and azides, and also show good tolerance towards functionalised substituents of alkynes and azides. Among them, the PPh3‐coordinated complexes 1, 5 and 6 afforded the highest catalytic activities [turnover frequency = 26.9–45.7 h–1].
Synthesis, Characterization and Electronic Properties of trans‐[4‐(Alkoxycarbonyl)phenyl]porphyrin‐[RuII(bpy)3]2 Complexes or Boron–Dipyrrin Conjugates as Panchromatic Sensitizers for DSSCs
Authors: Stangel Christina , Ladomenou Kalliopi , Charalambidis Georgios , Panda Manas K. , Lazarides Theodore , Coutsolelos Athanassios G.
Published: January 2013

Two porphyrin‐based dyes were synthesized that incorporate two additional chromophores to absorb in a wider UV/Vis region. In the first dye, a porphyrin ring is linked through an amide bond to two [Ru(bpy)3]2+ units, forming a symmetric [Ru(bpy)3]‐porphyrin‐[Ru(bpy)3] {Por(COOH)2[Ru(bpy)3]2} system. The second porphyrin is trans substituted through a triple bond to the meso position with two boron dipyrrin (BDP) molecules {Por(COOH)2(BDP)2}. Both porphyrins bear two carboxylic groups capable of binding onto a TiO2 surface, with potential applications in dye‐sensitized solar cells (DSSCs). The title dyes were characterized by means of 1H and 13C NMR spectroscopy, elemental analysis, MALDI‐TOF, UV/Vis absorption and emission studies.
Post‐Functionalization of an Anderson‐Type Polyoxomolybdate Using a Metal‐Free Diels–Alder Click Reaction
Authors: Yang Hai‐Kuan , Su Ming‐Ming , Ren Li‐Jun , Tang Jing , Yan Yu‐Kun , Miao Wen‐Ke , Zheng Ping , Wang Wei
Published: January 2013

Functionalization and post‐functionalization of polyoxometalates (POMs) by organic groups or biological moieties can provide versatile platforms for creating novel functional hybrids with synergetic properties. Such materials can easily be envisioned as having many advanced applications in biology and materials science. Nowadays, the organic groups or biological moieties used for conjugation with POMs, can readily become increasingly complicated in terms of structure, size and properties. Accordingly, a major challenge lies in the development of efficient conjugation methods. In this work, we report our application of metal‐free Diels–Alder click reactions under mild conditions to covalently link an Anderson‐type polyoxomolybdate with some organic groups or biological moieties possessing complex structures or different properties. High coupling efficiencies and facile purification methods guarantee > 90 % yields. Clearly, this is an ideal methodology for the synthesis of the post‐functionalized POM hybrids. With this technology now in hand, finding valuable applications for such post‐functionalized POM hybrids will be a highly significant focus of future investigations.
Wireless network coding design based on LDPC codes for a multiple‐access relaying system
Authors: Li Jun , Yuan Jinhong , Malaney Robert
Published: January 2013

In this paper, we investigate wireless network coding (WNC) in a multiple‐access relay channel (MARC) with two sources, one relay and one destination. We focus on a MARC with binary‐input additive white Gaussian noise (AWGN) channels, where two sources’ signals interfere at both the relay and the destination. Firstly, we derive the achievable rates for the WNC in the MARC over binary‐input AWGN channels. Secondly, considering the strong interference between the two sources, we propose a novel joint WNC and multi‐edge type low‐density party‐check (LDPC) code structure, which we refer to as the WNC–LDPC code. Then, on the basis of our code structure and the iterative receiver at the destination, we optimise the degree distributions of our WNC–LDPC code to approach the achievable sum rate of the MARC by utilising the extrinsic mutual information transfer (EXIT) analysis. In the simulations, we utilise physical‐layer network coding (PNC) as a benchmark for comparison purposes and design an LDPC code for the PNC (i.e. PNC–LDPC), which is used to compare with our WNC–LDPC code. Numerical results show that our WNC–LDPC code offers a much better bit error ratio performance relative to the PNC–LDPC code. Copyright © 2013 John Wiley & Sons, Ltd.
A lattice Boltzmann fictitious domain method for modeling red blood cell deformation and multiple‐cell hydrodynamic interactions in flow
Authors: Shi Xing , Lin Guang , Zou Jianfeng , Fedosov Dmitry A.
Published: January 2013

To model red blood cell (RBC) deformation and multiple‐cell interactions in flow, the recently developed technique derived from the lattice Boltzmann method and the distributed Lagrange multiplier/fictitious domain method is extended to employ the mesoscopic network model for simulations of RBCs in flow. The flow is simulated by the lattice Boltzmann method with an external force, while the network model is used for modeling RBC deformation. The fluid–RBC interactions are enforced by the Lagrange multiplier. To validate parameters of the RBC network model, stretching tests on both coarse and fine meshes are performed and compared with the corresponding experimental data. Furthermore, RBC deformation in pipe and shear flows is simulated, revealing the capacity of the current method for modeling RBC deformation in various flows. Moreover, hydrodynamic interactions between two RBCs are studied in pipe flow. Numerical results illustrate that the leading cell always has a larger flow velocity and deformation, while the following cells move slower and deform less.Copyright © 2013 John Wiley & Sons, Ltd.
Theory of Mind differences in older patients with early‐onset and late‐onset paranoid schizophrenia
Authors: Smeets‐Janssen M. M. J. , Meesters P. D. , Comijs H. C. , Eikelenboom P. , Smit J. H. , de Haan L. , Beekman A. T. F. , Stek M. L.
Published: January 2013

Objective

Theory of Mind (ToM) is considered an essential element of social cognition. In younger schizophrenia patients, ToM impairments have extensively been demonstrated. It is not clear whether similar impairments can be found in older schizophrenia patients and if these impairments differ between older patients with early‐onset and late‐onset schizophrenia.

Methods

Theory of Mind abilities were assessed using the Hinting Task in 15 older patients (age 60 years and older) with early‐onset paranoid schizophrenia, 15 older patients with late‐onset paranoid schizophrenia and 30 healthy controls. ANCOVA was performed to test differences between groups. Analyses were adjusted for level of education. Effect sizes, partial eta squared (ε2), were computed as an indication of the clinical relevance of the findings.

Results

Patients with early‐onset schizophrenia scored significantly lower on the Hinting Task (mean 16.1; SD 4.3) compared with patients with late‐onset schizophrenia (mean 18.6; SD 1.5) and with healthy controls (mean 19.0; SD 1.4). The effect size of this difference was large (ε2 = 0.2).

Conclusions

These results suggest that ToM functioning may be a protective factor modulating the age at onset of psychosis. Further studies into the relationship between social cognition and onset age of psychosis are warranted. Copyright © 2013 John Wiley & Sons, Ltd.
Treatment of glioblastoma multiforme using a combination of small interfering RNA targeting epidermal growth factor receptor and β‐catenin
Authors: Wang Kui , Park James O. , Zhang Miqin
Published: January 2013

Background

Epidermal growth factor receptor (EGFR) and β‐catenin are two key mediators of cell signal transduction implicated in the pathogenesis of a variety of tumors. There is emerging evidence indicating that they are overexpressed in glioblastoma multiforme (GBM) and both play significant roles in GBM carcinogenesis. Moreover, down‐regulating EGFR individually only provides limited therapeutic efficacy. Therefore, we aimed to determine the feasibility and efficacy of gene therapy of GBM using combinatorial inhibition of EGFR and β‐catenin in view of the cross‐talk between these two signaling pathways.

Methods

The down‐regulatory effect of small interfering RNA (siRNA) targeting EGFR and β‐catenin alone or in combination in human GBM cells U‐87 MG was evaluated by Quantitative RT‐PCR. Cell proliferation in the short‐ and long‐term was investigated by alamar blue and clonogenic assays, respectively. An annexin‐V assay was performed to detect apoptosis caused by siRNA treatment. The effect of downregulating EGFR and β‐catenin on cell cycle progression, cell migration and invasive potential were also examined.

Results

The siRNA treatment potently reduced gene expression of EGFR and β‐catenin at the mRNA level. Simultaneous inhibition of EGFR and β‐catenin greatly decreased GBM cell proliferation. Although no significant increase in apoptosis was demonstrated, combinatorial siRNA treatment delayed the progression of cell cycle with an increased proportion of cells arrested in the G0/1 phase. Furthermore, EGFR and β‐catenin siRNA in combination significantly inhibited the migratory and invasive ability of GBM cells.

Conclusions

Simultaneous inhibition of EGFR and β‐catenin expression could represent an effective therapy for human GBM, and warrants further study in vivo. Copyright © 2013 John Wiley & Sons, Ltd.
High efficiency gene transfer to airways of mice using influenza hemagglutinin pseudotyped lentiviral vectors
Authors: Patel Manij , Giddings Angela M. , Sechelski John , Olsen John C.
Published: January 2013

Background

A limitation to efficient lentivirus‐mediated airway gene transfer is the lack of receptors to commonly used viral envelopes on the luminal surface of airway epithelia. The use of viral envelopes with natural tropism to the airway could be useful for overcoming this limitation.

Methods

We investigated influenza hemagglutinin (HA) pseudotyped equine infectious anemia virus‐derived lentiviral vector‐mediated gene transfer to the airway epithelium of adult and newborn mice. For these studies, high‐titer vectors were delivered by intranasal administration. In addition, we tested the feasibility of vector re‐dosing to the nasal airway.

Results

Delivery of high‐titer HA pseudotyped lentiviral vectors by nasal administration to newborn mouse pups or adult mice results in the efficient transduction of airway epithelial cells in the nose, trachea, and lungs. In the nose, vector expression was predominant in the respiratory epithelium and was not observed in the olfactory epithelium. In the trachea and large airways of the lung, approximately 46% and 40%, respectively, of surface epithelial cells could be transduced. The efficiency of re‐dosing to the nasal airway of mice was found to be dependent of the age of the animal when the first dose is administered, as well as the length of time between doses.

Conclusions

A single intranasal dose of concentrated influenza HA‐pseudotyped lentiviral vector is sufficient for efficient gene transfer to the airways of mice. This is a promising result that could lead to the development of effective gene transfer reagents for the treatment of cystic fibrosis and other human lung diseases. Copyright © 2013 John Wiley & Sons, Ltd.
Trace level determination of polycyclic aromatic hydrocarbons in river water with automated pretreatment HPLC
Authors: Watabe Yoshiyuki , Kubo Takuya , Tanigawa Tetsuya , Hayakawa Yoshihiro , Otsuka Koji , Hosoya Ken
Published: January 2013

A novel on‐line pretreatment pump‐injection HPLC system for polycyclic aromatic hydrocarbons is proposed. We report novel pump‐injection HPLC‐based on‐line SPE with a specially designed pretreatment column for the determination of trace amounts of chemical substances in surface water. Polycyclic aromatic hydrocarbons are well known for strong carcinogenicity and thus a severe concentration control is required for drinking water and/or river water, which is the main resource of tap water. We found it possible to detect ng/L levels of polycyclic aromatic hydrocarbons by using pump‐injection column switching HPLC with fluorescence detection. To avoid the phenomenon, in which polycyclic aromatic hydrocarbons can be often adsorbed on the surface of flow lines of HPLC by their highly hydrophobicity especially resin‐made parts in sample delivery pump, we employed “autodilution” device that provides reliable recovery and repeatability. Additionally, real water samples were collected and then the spiked polycyclic aromatic hydrocarbons were determined at ng/L levels.
Mental and Physical Health Consequences of the September 11, 2001 (9/11) Attacks in Primary Care: A Longitudinal Study
Authors: Neria Yuval , Wickramaratne Priya , Olfson Mark , Gameroff Marc J. , Pilowsky Daniel J. , Lantigua Rafael , Shea Steven , Weissman Myrna M.
Published: January 2013

The magnitude of the September 11, 2001 (9/11) attacks was without precedent in the United States, but long‐term longitudinal research on its health consequences for primary care patients is limited. We assessed the prevalence and exposure‐related determinants of mental disorders, functioning, general medical conditions, and service utilization, 1 and 4 years after the 9/11 attacks, in an urban primary care cohort (N = 444) in Manhattan. Although the prevalence of posttraumatic stress disorder (PTSD) and levels of functional impairment declined over time, a substantial increase in suicidal ideation and missed work was observed. Most medical outcomes and service utilization indicators demonstrated a short‐term increase after the 9/11 attacks (mean change of +20.3%), followed by a minor decrease in the subsequent year (mean change of −3.2%). Loss of a close person was associated with the highest risk for poor mental health and functional status over time. These findings highlight the importance of longitudinal assessments of mental, functional, and medical outcomes in urban populations exposed to mass trauma and terrorism.
Improving Solar Cell Efficiency by Effective Light Management
Authors: Knüttel Tobias , Bergfeld Stefan
Published: January 2013

The project “LaText” aims to develop new laser processes for texturing Transparent Conductive Oxides (TCO) to improve light management in thin film silicon solar cells. These new processes could improve cell efficiencies, reduce production costs or make inline processes like roll‐to‐roll production without vacuum brake possible. Retro fitting of existing production lines is also possible. 4JET and the Institute of Photovoltaics (IEK‐5) at the Research Center Jülich work together in this project.
Integrated Active Sensors for Process Monitoring
Authors: Blomqvist Mats , Blomster Ola , Bergstrand Hans
Published: January 2013

In industrial materials processing applications using high‐brilliance multikW lasers there is an increasing demand to continuously monitor the process status even in passive components such as fiber‐optic cables. While monitoring the sensor signals for system safety the information can also be used for live process monitoring. By using integrated active sensors inside the process fiber a compact and robust solution for industrial manufacturing can be achieved.
Combination of Episulfide Ring‐Opening Polymerization With ATRP for the Preparation of Amphiphilic Block Copolymers
Authors: Vo Cong‐Duan , Cadman Christopher J. , Donno Roberto , Goos Jeroen A. C. M. , Tirelli Nicola
Published: January 2013

We report for the first time the combination of ATRP and ring‐opening episulfide polymerization as a means to synthesize polysulfide‐based low‐dispersity amphiphilic block copolymers. The most significant finding is the possibility to perform ATRP under mild conditions using poly(propylene sulfide) macroinitiators, apparently without any significant copper sequestration by the polysulfides. Using glycerol monomethacrylate (GMMA) as a hydrophilic monomer, the polymers self‐assembled in colloidal structures with a morphology depending on the PS/GMMA ratio, but also probably on GMMA degree of polymerization. We here also present a new AFM‐based method to calculate the average number of amphiphilic macromolecules per micelle.
Self‐Healing Polymers via Supramolecular Forces
Authors: Herbst Florian , Döhler Diana , Michael Philipp , Binder Wolfgang H.
Published: January 2013

As polymers and polymeric materials are “the” smart invention and technological driving force of the 20th century, the quest for self‐healing or self‐repairing polymers is strong. The concept of supramolecular self‐healing materials relies on the use of noncovalent, transient bonds to generate networks, which are able to heal the damaged site, putting aspects of reversibility and dynamics of a network as crucial factors for the understanding and design of such self‐healing materials. This Review describes recent examples and concepts of supramolecular polymers based on hydrogen bonding, π–π interactions, ionomers, and coordinative bonds, thus convincingly discussing the advantages and versatility of these supramolecular forces for the design and realization of self‐healing polymers.
The Efficiency of Agricultural Marketing Cooperatives in China's Zhejiang Province
Authors: Huang Zuhui , Fu Yuzhi , Liang Qiao , Song Yu , Xu Xuchu
Published: January 2013

On the basis of the bootstrap‐Data Envelopment Analysis (DEA), this paper estimates technical, scale, and pure technical efficiencies for the agricultural marketing cooperatives in China's Zhejiang Province and employs a single truncated bootstrap procedure to identify the key determinants of efficiencies. The empirical results suggest that pure technical inefficiency was the main source of the technical inefficiency. Factors having significantly positive impacts on efficiency of cooperatives are local economic development level, entrepreneurship of managers, and human capital of members. The size of financial leverage and the number of board members have a negative impact on pure technical efficiency. Copyright © 2013 John Wiley & Sons, Ltd.
Effectiveness of CASE Ultra Expert System in Evaluating Adverse Effects of Drugs
Authors: Saiakhov Roustem , Chakravarti Suman , Klopman Gilles
Published: January 2013

Purpose of this pilot study is to test the QSAR expert system CASE Ultra for adverse effect prediction of drugs. 870 drugs from the SIDER adverse effect dataset were tested using CASE Ultra for carcinogenicity, genetic, liver, cardiac, renal and reproductive toxicity. 47 drugs that were withdrawn from market since the 1950s were also evaluated for potential risks using CASE Ultra and compared them with the actual reasons for which the drugs were recalled. For the whole SIDER test set (n=870), sensitivity and specificity of the carcinogenicity predictions are 66.67 % and 82.17 % respectively; for liver toxicity: 78.95 %, 78.50 %; cardiotoxicity: 69.07 %, 57.57 %; renal toxicity: 46.88 %, 67.90 %; and reproductive toxicity: 100.00 %, 61.10 %. For the SIDER test chemicals not present in the training sets of the models, sensitivity and specificity of carcinogenicity predictions are 100.00 % and 88.89 % respectively (n=404); for liver toxicity: 100.00 %, 51.33 % (n=115); cardiotoxicity: 100.00 %, 20.45 % (n=94); renal toxicity: 100.00 %, 45.54 % (n=115); and reproductive toxicity: 100.00 %, 48.57 % (n=246). CASE Ultra correctly recognized the relevant toxic effects in 43 out of the 47 withdrawn drugs. It predicted all 9 drugs that were not part of the training set of the models, as unsafe.
Exploiting Pharmacological Similarity to Identify Safety Concerns – Listen to What the Data Tells You
Authors: Muthas Daniel , Boyer Scott
Published: January 2013

Whilst most new drugs are designed to act on a single target or a small number of targets, many do show broad pharmacological activity. In some cases this can be beneficial and necessary for efficacy and in others it can be detrimental, leading to increased safety liability. To probe off‐target pharmacology most drug discovery programs include screening against a broad panel of targets that represent known troublesome pharmacology. Hits against any one of these targets can then be subjected to a risk assessment for potential safety problems in preclinical or clinical studies. In addition, the secondary pharmacology profile can also be thought of as an alternative description of the compound and as such can be used as a method for assessing ‘similarity’. Consequently, inspection of the in vivo findings of pharmacological neighbors can give important insights into potential safety liabilities that are neither identified by pure chemical similarity searches nor by risk assessment on individual targets. Here we show that the pharmacological profile contains additional information as compared to chemical similarity, and also demonstrate how this can be used in the hazard assessment done during drug discovery and development.
Model Suite for Predicting the Aquatic Toxicity of α,β‐Unsaturated Esters Triggered by Their Chemoavailability
Authors: Mulliner Denis , Schüürmann Gerrit
Published: January 2013

For a Michael‐acceptor set of 45 α,β‐unsaturated esters, the 2nd‐order rate constant of reaction with glutathione, log kGSH, was modeled through the quantum chemical reaction barrier (ΔE≠) employing methane thiol as model nucleophile. Regression of their 48‐h toxicity toward the ciliates Tetrahymena pyriformis (log EC50, 50 % growth inhibition) on log Kow (octanol/water partition coefficient) and log kGSH revealed a variation in the relative weights of hydrophobicity and electrophilic reactivity as determinants of the aquatic toxicity. The difference DKk=log Kow−log kGSH turned out as a suitable means for predictively discriminating between narcosis‐level (DKk>3.0) and excess‐toxic (DKk<2.0) compounds. In the intermediate DKk range (2.0≤DKk≤3.0), both narcosis‐level and reactive‐toxicity models are applicable for predicting aquatic toxicity. As such, DKk represents the chemoavailability of Michael‐acceptor esters, characterizing their likelihood for undertaking covalent reactions with thiol sites of endogenous peptides and proteins. At the same time, DKk introduces a straightforward way for characterizing the applicability domain of QSAR (quantitative structure‐activity relationship) models for predicting the toxicity of Michael‐acceptor esters. The resultant model suite comprising QSARs for reactive toxicity and baseline narcosis is triggered by the compounds’ chemoavailability, and yields predictions superior to existing approaches.