bluuebunny/crossref_metadata_2025_split huggingface dataset:
Radial approach for percutaneous coronary interventions on chronic total occlusions: Technical issues and data review
Authors: Burzotta Francesco , De Vita Maria , Lefevre Thierry , Tommasino Antonella , Louvard Yves , Trani Carlo 
Published: July 2013

ObjectiveTo overview the scientific data and the technical details regarding percutaneous coronary interventions (PCI) on chronic total occlusions (CTO) by radial approach.BackgroundTrans‐femoral approach is commonly regarded as the standard for PCI on CTO.MethodsA systematic search in Medline and in the main international websites was realized. Key data were extracted and analyzed using standard meta‐analytic techniques. Bench test assessment of compatibility between different combinations of interventional devices (required for CTO recanalization techniques) and the following guiding catheters was performed: 5 Fr, Sheathless 6.5 Fr, 6 Fr, Sheathless 7.5 Fr and 8 Fr.ResultsNo prospective randomized study was found, whereas 13 observational studies on 3,501 CTOs treated by radial approach were identified. Overall, the crossover to femoral access rate ranged between 0 and 5.8%. Access site complications were noted in <1% of cases and in‐hospital major adverse events were reported in 0–3.8% of patients. PCI success was significantly influenced by the learning curve: In the five studies comparing the success rates between a first and a later period of practice, a significant improvement was observed (OR, 95% CI: 0.30, 0.39–0.51; P < 0.001). The technical details relevant to approach a CTO by transradial access are discussed, and the original results of bench tests provide details regarding the compatibility of various CTO recanalization techniques with specific guiding catheter sizes.ConclusionsThe transradial access represents a promising alternative to trans‐femoral access to treat patients undergoing CTO PCI in high‐volume transradial centres. The presented data may be useful to plan transradial PCI attempts on CTO lesions. © 2013 Wiley Periodicals, Inc.
Time Evolution of the Stability and Oxygen Reduction Reaction Activity of PtCu/C Nanoparticles
Authors: Jeyabharathi Chinnaya , Hodnik Nejc , Baldizzone Claudio , Meier Josef C. , Heggen Marc , Phani Kanala L. N. , Bele Marjan , Zorko Milena , Hocevar Stanko , Mayrhofer Karl J. J. 
Published: July 2013

AbstractCrystalline Cu3Pt nanoparticles supported on graphitized carbon are synthesized by using a modified sol–gel method, and subsequent thermal annealing leads to alloying of Pt with Cu and formation of a partially ordered Pm${\bar 3}$m structure. Electrochemical dealloying under potentiodynamic conditions (potential cycling) induces not only changes from rather spherical high‐index faceted to more cuboctahedral low‐index faceted core–shell structures for particles in a size range of 10–20 nm but also percolation for some particles larger than 20 nm. In contrast, during dealloying under potentiostatic conditions (potential hold) the semispherical shape of small particles is completely retained and extensive porosity is formed on all particles larger than 20 nm. Other degradation processes are not observed on performing an additional accelerated aging test; hence, the high specific and mass activity of the catalyst decreases only slightly, mainly owing to continuing Cu leaching. The difference in dealloying protocols and their effect on the structure of the catalysts as well as their activities, considering the promising porosity formation, are discussed and indicate future directions for a rational design of active and stable oxygen reduction reaction catalysts.
Power Consumption of Liquid and Liquid/Solid Systems in a Rotating‐Drum Bioreactor
Authors: Wang Z. , Wen S. , Zhang Q. , Liu G. , Wu X. , Cong W. 
Published: July 2013

AbstractRotating‐drum bioreactors combine the advantage of quiescent environment with mild shear stress for microbial growth. Power consumption is a vital parameter to evaluate the performance of reactors. To provide primary information for design and optimization of the rotating‐drum bioreactor, the effects of lifter arrangement conditions including number of lifters, lifter width and mounted angles, and operation conditions such as rotational speed, aeration rate, and solid volume fraction on power consumption were tested. Based on the experimental data, correlations for the power consumption of liquid and liquid/solid systems were proposed.
Wet Flue Gas Desulfurization Process: Phase Equilibrium of a Quaternary System at Various Temperatures
Authors: Ji Z.‐Y. , Song B.‐H. , Yuan J.‐S. , Wang Z.‐Y. , Wang J. , Li L.‐M. 
Published: July 2013

AbstractIn an eco‐friendly technology, MgSO4·7H2O is produced as a by‐product in the magnesium‐based wet flue gas desulfurization (FGD) process. Equilibrium data for the quaternary system of MgSO4‐MgCl2‐CaSO4‐CaCl2‐H2O at 308.15 K, 338.15 K, and 368.15 K were investigated using the method of isothermal solution saturation. The dry‐salt phase diagram of the system mainly includes the three‐salt co‐saturated point, solubility isotherm curves, and crystallization regions. The results could provide assistance for producing MgSO4 as a by‐product with evaporation crystallization in the magnesium‐based wet FGD process.
Bare Histidine–Serine Models: Implication and Impact of Hydrogen Bonding on Nucleophilicity
Authors: Leclaire Julien , Mazari Messaoud , Zhang Yuan , Bonduelle Colin , Thillaye du Boullay Olivier , Martin‐Vaca Blanca , Bourissou Didier , De Riggi Innocenzo , Fortrie Rémy , Fotiadu Frédéric , Buono Gérard 
Published: July 2013

AbstractA new family of 2‐hydroxyalk(en/yn)ylimidazoles has been evaluated as serine–histidine bare dyad models for the ring‐opening reaction of L‐lacOCA, a cyclic O‐carboxyanhydride. These models were selected to unravel the implication of intramolecular hydrogen bonding and to substantiate its influence on the nucleophilicity of the alcohol moiety, as it is suspected to occur in enzyme active sites. Although designed to exclusively facilitate the preliminary step of proton transfer during the studied ring‐opening reaction, these minimalistic models depicted a measureable increase in reactivity relative to the isolated fragments. A couple of reliable experimental and theoretical methods have been developed to readily monitor the strength of the intramolecular hydrogen bond in dilute solution. Results show that the folded conformers are the most nucleophilic species because of the intramolecular hydrogen bond.
A Highly Efficient Synthesis of Optically Active Ferrocenylethylamines via Hydride Reduction of Chiral Ferrocenylketimines
Authors: Qian Hengyu , Yan Shihai , Cui Xiuling , Pi Chao , Liu Cheng , Wu Yangjie 
Published: July 2013

AbstractDue to using (R)‐ or (S)‐α‐methylbenzylamine as a chiral auxiliary, and low‐temperature regime for reduction of the intermediate ferrocenyl‐mono‐ or 1,1′‐bis‐ketimines, the corresponding secondary mono‐ or 1,1′‐bis‐amines were prepared with high diastereoselectivity. Removal of the α‐methylbenzyl group afforded the optically active primary mono‐ and bis‐ferrocenylethylamines in high yields. The absolute configuration of (R,R)‐3a and (S,S)‐3b was determined by X‐ray single crystal diffraction.
Surface Modification of Bituminous Coal and Its Effects on Methane Adsorption
Authors: Feng Yanyan , Yang Wen , Liu Daijun , Chu Wei 
Published: July 2013

AbstractThis paper studied the role of O‐containing groups over the coal surface in methane adsorption. The coal was modified with H2SO4, (NH4)2S2O8 or H2SO4/(NH4)2S2O8), respectively, to introduce O‐containing functional groups, and characterized by proximate analysis, ultimate analysis, Boehm titration, X‐ray photoelectron spectroscopy (XPS) and nitrogen adsorption. The results of ultimate analysis, Boehm titration and XPS indicate that there were increases in terms of both the content of oxygen and the quantities of O‐containing groups over the modified coals surface, especially for the carboxyl. Nitrogen adsorption shows that the modified coals possessed higher surface area and pore volume than that of 0‐XQ. The methane adsorption data were measured at 298 K at pressures up to 4.0 MPa by the volumetric method and fitted well by Langmuir model. Experimental results implied that O‐containing groups and pore structure affected methane adsorption. The adsorption capacities decreased as increasing quantities of O‐containing groups.
Copper(I)‐Catalyzed Trifluoromethylation of Phthalic Anhydride Derivatives with (Trifluoromethyl)trimethylsilane
Authors: Wu Mingxi , Wang Mingjin , Cao Song 
Published: July 2013

AbstractAn efficient copper‐catalyzed trifluoromethylation of substituted phthalic anhydrides using (trifluoromethyl) trimethylsilane (Me3SiCF3) as a nucleophilic trifluoromethylating reagent in the presence of 1,10‐phenanthroline and KF, followed by quenching the reaction mixture with water has been developed. A possible mechanism was suggested.
Nucleophilic Trifluoromethylthiolation of Allylic Bromides: A Facile Preparation of Allylic Trifluoromethyl Thioethers
Authors: Tan Jianwei , Zhang Guoting , Ou Yangli , Yuan Yaofeng , Weng Zhiqiang 
Published: July 2013

AbstractA facile preparation of allylic trifluoromethyl thioethers was achieved by using a copper reagent. The reaction of (bpy)Cu(SCF3) with various allylic bromides afforded the desired trifluoromethylthiolation products in good to excellent yields with high stereo‐ and regioselectivity. Common functional groups such as alkyl, alkoxy, trifluoromethyl, nitro, halides and geranyl are well tolerated.
Palladium‐Catalyzed Intramolecular Fluorooxylation of Styrenes
Authors: Yuan Zheliang , Peng Haihui , Liu Guosheng 
Published: July 2013

AbstractA novel palladium‐catalyzed intramolecular fluorooxylation of styrenes has been developed by using NFSI as fluorinating reagent. This reaction provides an efficient way for the synthesis of 2‐aryl‐3‐fluorotetrahydrofuran derivatives.
(Strong) multidesignated verifiers signatures secure against rogue key attack
Authors: Au Man Ho , Yang Guomin , Susilo Willy , Zhang Yunmei 
Published: July 2013

SUMMARYDesignated verifier signatures (DVS) allow a signer to create a signature whose validity can only be verified by a specific entity chosen by the signer. In addition, the chosen entity, known as the designated verifier, cannot convince any body that the signature is created by the signer. Multidesignated verifiers signatures (MDVS) are a natural extension of DVS in which the signer can choose multiple designated verifiers. DVS and MDVS are useful primitives in electronic voting and contract signing. In this paper, we investigate various aspects of MDVS and make two contributions. Firstly, we revisit the notion of unforgeability under rogue key attack on MDVS. In this attack scenario, a malicious designated verifier tries to forge a signature that passes through the verification of another honest designated verifier. A common counter‐measure involves making the knowledge of secret key assumption in which an adversary is required to produce a proof‐of‐knowledge of the secret key. We strengthened the existing security model to capture this attack and propose a new construction that does not rely on the knowledge of secret key assumption. Secondly, we propose a generic construction of strong MDVS. Copyright © 2013 John Wiley & Sons, Ltd.
Overcoming Bottlenecks of Enzymatic Biofuel Cell Cathodes: Crude Fungal Culture Supernatant Can Help to Extend Lifetime and Reduce Cost
Authors: Sané Sabine , Jolivalt Claude , Mittler Gerhard , Nielsen Peter J. , Rubenwolf Stefanie , Zengerle Roland , Kerzenmacher Sven 
Published: July 2013

AbstractInvited for this month′s cover is the Biofuel Cell research group of Sven Kerzenmacher at the University of Freiburg. The image illustrates that the wood‐degrading fungus Trametes versicolor can be used to resupply the redox enzyme laccase at an enzymatic biofuel cell cathode. Read the full text of the article on page 1209
Comparing food limitation among three stages of nesting: supplementation experiments with the burrowing owl
Authors: Wellicome Troy I. , Danielle Todd L. , Poulin Ray G. , Holroyd Geoffrey L. , Fisher Ryan J. 
Published: July 2013

AbstractFood availability is an important limiting factor for avian reproduction. In altricial birds, food limitation is assumed to be more severe during the nestling stage than during laying or incubation, but this has yet to be adequately tested. Using food‐supplementation experiments over a 5‐year period, we determined the degree and timing of food limitation for burrowing owls (Athene cunicularia) breeding in Canada. Burrowing owls are an endangered species and food limitation during the nestling stage could influence reproductive performance of this species at the northern extent of their range. Supplemented pairs fledged on average 47% more owlets than unfed pairs, except during a year when natural food was not limiting (i.e., a prey irruption year). The difference in fledgling production resulted from high nestling mortality in unfed broods, with 96% of all nestling deaths being attributed to food shortage. Supplemental feeding during the nestling period also increased fledgling structural size. Pairs fed from the start of laying produced the same number of hatchlings as pairs that received no supplemental food before hatch. Furthermore, pairs supplemented from egg laying to fledging and pairs supplemented during the nestling period alone had the same patterns of nestling survival, equal numbers of fledglings, and similar fledgling mass and structural size. Our results provide empirical support for the hypothesis that the nestling period is the most food‐limited phase of the breeding cycle. The experimental design we introduce here could be used with other altricial species to examine how the timing of food limitation differs among birds with a variety of life‐history strategies. For burrowing owls, and other species with similar life histories, long‐term, large‐scale, and appropriately timed habitat management increasing prey abundance or availability is critical for conservation.
Selective Extraction and Efficient Binding in a Protic Solvent of Contact Ion Triplets by Using a Thiourea‐Based Bis‐Calix[6]arene Receptor
Authors: Moerkerke Steven , Le Gac Stéphane , Topić Filip , Rissanen Kari , Jabin Ivan 
Published: July 2013

AbstractWe report a D3h‐symmetric tail‐to‐tail bis‐calix[6]thiourea 5 that displays two divergent cavities triply connected by thiourea linkages. This calix[6]tube was efficiently synthesized through a [1+1] macrocyclization reaction and characterized by X‐ray diffraction analysis. The binding properties of this heterotritopic receptor were evaluated in a protic environment (i.e., CD3OD/CDCl3) through NMR studies. Thus, bis‐calix[6]thiourea 5 exhibits a remarkable ability in the cooperative complexation of an anion sandwiched between two ammonium ions, a high selectivity for ammonium sulfate salts being observed. The anion is bound through multiple hydrogen‐bonding interactions at the thiourea binding site and is in contact with the two ammonium ions accommodated in the cavities. The resulting quaternary complexes are rare examples of cascade complexes involving organic cations. Moreover, when wrapping around the anion, the thiourea linkers adopt a helical shape and the resulting chirality is sensed by the bound cations. In comparison with the parent amido‐ or urea‐based bis‐calix[6]arenes 1 and 2, bis‐calix[6]thiourea 5 behaves as a much more efficient receptor for organic ion triplets. This strengthening of the binding properties is likely due to the higher acidity of the thiourea groups and to their poor ability to self‐associate. Interestingly, we have obtained the first X‐ray structure of a bis‐calix[6]arene‐based cascade complex. It shows that these host–guest complexes are stabilized through a dense network of hydrogen‐bonding interactions. Finally, although sulfate salts are better recognized in CD3OD/CDCl3, the selective extraction of ammonium nitrate salts from water to chloroform was evidenced through NMR studies. This remarkable result can be rationalized by the weaker hydration of the nitrate anion and its good geometrical complementarity with the tris‐thiourea binding site.
Chameleonic social identities: Context induces shifts in homosexuals' self‐stereotyping and self‐categorization
Authors: Cadinu Mara , Galdi Silvia , Maass Anne 
Published: July 2013

AbstractDo people align their self‐concepts to the environment? It was predicted that low‐status (homosexuals), but not high‐status group members (heterosexuals), respond to environmental cues by shifting the type of self‐categorization and self‐stereotyping. In the presence (vs. absence) of environmental cues to sexual orientation, homosexual individuals felt more talented for typically homosexual jobs and showed greater self‐stereotyping on typically homosexual traits (Experiment 1). Using implicit measures of self‐categorization and self‐stereotyping, we observed parallel findings for homosexuals, but not for heterosexuals (Experiment 2). Results are discussed in relation to research on stigma, with particular attention to the potential benefits for low‐status group members of changing their implicit self‐concept flexibly across situations. Copyright © 2013 John Wiley & Sons, Ltd.
Ultrasound versus palpation guidance for intra‐articular injections in patients with degenerative osteoarthritis of the elbow
Authors: Kim Tai Kon , Lee Ji Hae , Park Ki Deok , Lee Sang Chul , Ahn Jaeki , Park Yongbum 
Published: July 2013

ABSTRACTObjectivesThe aim of this study is to evaluate the accuracy rate of ultrasound (US) ‐guided intra‐articular (IA) injections in patients by posterior approach with osteoarthritis (OA) of the elbow.MethodsEighty patients with physical examination and radiographic findings of elbow OA were included. After US‐guided IA or palpation‐guided IA injection of iohexol contrast by posterior approach into the elbow joint, fluoroscopic images were obtained to ascertain whether the injected material had reached the IA space.ResultsOf the 40 injections performed by US guidance, 40 were confirmed to have been placed in the IA space (an accuracy rate of 100%). Thirty‐one of the 40 injections performed by the palpation guidance were IA space (77.5% accuracy rate).ConclusionsUS‐guided IA elbow injections by posterior approach may raise the accuracy rate in elbow joint injections. © 2013 Wiley Periodicals, Inc. J Clin Ultrasound, 41:479–485, 2013;
The Effect of N/P Ratio on the In Vitro and In Vivo Interaction Properties of PEGylated Poly[2‐(dimethylamino)ethyl methacrylate]‐Based siRNA Complexes
Authors: Gary Dana J. , Min Jungbin , Kim Youngwook , Park Keunchil , Won You‐Yeon 
Published: July 2013

AbstractPEG‐PnBA‐PDMAEMA triblock and PEG‐PDMAEMA diblock copolymers are used as model systems for studying the role of N/P ratio on the in vivo behavior of PEGylated siRNA carriers in mice. The presence of a free/uncomplexed polymer population coexisting with siRNA complexes is established. A change in the N/P ratio exerts no significant influence on the in vivo biodistribution and ex vivo blood chemistry properties of the respective systems. Histological analysis of major organs indicates that the presence of uncomplexed polymer elicits toxicity to the organ that is associated with the clearance of the siRNA complexes from the circulation system. This effect can be eliminated by working at N/P ratios near the charge‐neutralization point of the complexes.
Reaction Kinetics and Thermodynamic Aspects of Thermoreversibly Cross‐Linked Polymer Networks
Authors: Peterson Amy M. , Palmese Giuseppe R. 
Published: July 2013

AbstractThe Diels–Alder reaction of furan and maleimide is used to prepare reversibly cross‐linking polymer gels consisting of furan‐bearing polymer chains and bismaleimides. The roles of chain length, stoichiometry, and concentration on gelation kinetics and other properties are evaluated. Additionally, kinetics of the Diels–Alder reactions in the gelling system are compared with the kinetics of small molecule systems. By combining spectroscopic and rheological techniques, a mechanochemical analysis is performed.magnified image
Molecular dynamics simulations give insight into the conformational change, complex formation, and electron transfer pathway for cytochrome P450 reductase
Authors: Sündermann Axel , Oostenbrink Chris 
Published: July 2013

AbstractCytochrome P450 reductase (CYPOR) undergoes a large conformational change to allow for an electron transfer to a redox partner to take place. After an internal electron transfer over its cofactors, it opens up to facilitate the interaction and electron transfer with a cytochrome P450. The open conformation appears difficult to crystallize. Therefore, a model of a human CYPOR in the open conformation was constructed to be able to investigate the stability and conformational change of this protein by means of molecular dynamics simulations. Since the role of the protein is to provide electrons to a redox partner, the interactions with cytochrome P450 2D6 (2D6) were investigated and a possible complex structure is suggested. Additionally, electron pathway calculations with a newly written program were performed to investigate which amino acids relay the electrons from the FMN cofactor of CYPOR to the HEME of 2D6. Several possible interacting amino acids in the complex, as well as a possible electron transfer pathway were identified and open the way for further investigation by site directed mutagenesis studies.
The dynamics of camphor in the cytochrome P450 CYP101D2
Authors: Vohra Shabana , Musgaard Maria , Bell Stephen G. , Wong Luet‐Lok , Zhou Weihong , Biggin Philip C. 
Published: July 2013

AbstractThe recent crystal structures of CYP101D2, a cytochrome P450 protein from the oligotrophic bacterium Novosphingobium aromaticivorans DSM12444 revealed that both the native (substrate‐free) and camphor‐soaked forms have open conformations. Furthermore, two other potential camphor‐binding sites were also identified from electron densities in the camphor‐soaked structure, one being located in the access channel and the other in a cavity on the surface near the F‐helix side of the F‐G loop termed the substrate recognition site. These latter sites may be key intermediate positions on the pathway for substrate access to or product egress from the active site. Here, we show via the use of unbiased atomistic molecular dynamics simulations that despite the open conformation of the native and camphor‐bound crystal structures, the underlying dynamics of CYP101D2 appear to be very similar to other CYP proteins. Simulations of the native structure demonstrated that the protein is capable of sampling many different conformational substates. At the same time, simulations with the camphor positioned at various locations within the access channel or recognition site show that movement towards the active site or towards bulk solvent can readily occur on a short timescale, thus confirming many previously reported in silico studies using steered molecular dynamics. The simulations also demonstrate how the fluctuations of an aromatic gate appear to control access to the active site. Finally, comparison of camphor‐bound simulations with the native simulations suggests that the fluctuations can be of similar level and thus are more representative of the conformational selection model rather than induced fit.