bluuebunny/crossref_metadata_2025 huggingface dataset:
Difference of two dependent sensitivities and specificities: Comparison of various approaches
Authors: Wenzel Daniela , Zapf Antonia
Published: July 2013

In diagnostic studies, a new diagnostic test is often compared with a standard test and both tests are applied on the same patients, called paired design. The true disease state is in general given by the so‐called gold standard (most reliable method for classification), which has to be known for all patients. The benefit of the new diagnostic test can be evaluated by sensitivity and specificity, which are in fact proportions. This means, for the comparison of two diagnostic tests, confidence intervals for the difference of the dependent estimated sensitivities and specificities are calculated. In the literature, many comparisons of different approaches can be found, but none explicitly for diagnostic studies. For this reason we compare 13 approaches for a set of scenarios that represent data of diagnostic studies (e.g., with sensitivity and specificity ⩾0.8). With simulation studies, we show that the nonparametric interval with normal approximation can be recommended for the difference of two dependent sensitivities or specificities without restriction, the Wald interval with the limitation of slightly anti‐conservative results for small sample sizes, and the nonparametric intervals with t‐approximation, and the Tango interval with the limitation of conservative results for high correlations.
Comparison of the binding behavior of FCCP with HSA and HTF as determined by spectroscopic and molecular modeling techniques
Authors: Moghaddam Maryam Mahmoodian , Pirouzi Malihe , Saberi Mohammad Reza , Chamani Jamshidkhan
Published: July 2013

The interaction of carbonylcyanide p‐(trifluoromethoxy) phenylhydrazone (FCCP) with human serum albumin (HSA) and human transferrin (HTF) was investigated using multiple spectroscopy, molecular modeling, zeta‐potential and conductometry measurements of aqueous solutions at pH 7.4. The fluorescence, UV/vis and polarization fluorescence spectroscopy data disclosed that the drug–protein complex formation occurred through a remarkable static quenching. Based on the fluorescence quenching, two sets of binding sites with distinct affinities for FCCP existed in the two proteins. Steady‐state and polarization fluorescence analysis showed that there were more affinities between FCCP and HSA than HTF. Far UV‐CD and synchronous fluorescence studies indicated that FCCP induced more structural changes on HSA. The resonance light scattering (RLS) and zeta‐potential measurements suggested that HTF had a greater resistance to drug aggregation, whereas conductometry measurements expressed the presence of free ions improving the resistance of HSA to aggregation. Thermodynamic measurements implied that a combination of electrostatic and hydrophobic forces was involved in the interaction between FCCP with both proteins. The phase diagram plots indicated that the presence of second binding site on HSA and HTF was due to the existence of intermediate structures. Site marker competitive experiments demonstrated that FCCP had two distinct binding sites in HSA which were located in sub‐domains IIA and IIIA and one binding site in the C‐lobe of HTF as confirmed by molecular modeling. The obtained results suggested that both proteins could act as drug carriers, but that the HSA potentially had a higher capacity for delivering FCCP to cancerous tissues. Copyright © 2013 John Wiley & Sons, Ltd.
Sensitive and selective system of benzene detection based on a cataluminescence sensor
Authors: Li Bo , Zhang Yuejin , Liu Juefu , Xie Xin , Zou Dan , Li Minqiang , Liu Jinhuai
Published: July 2013

Au/La2O3 nanomaterials were prepared through calcining Au‐modified La(OH)3 precursors. Scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X‐ray diffractometry (XRD) were employed to characterize the as‐prepared samples. Benzene, a common volatile organic compound, was selected as a model to investigate the cataluminescence (CTL)‐sensing properties of the Au/La2O3 nanomaterials. Results indicated that the as‐prepared Au/La2O3 exhibited outstanding CTL properties such as stable intensity, high signal‐to‐noise values, and short response and recovery times. Under optimized conditions, the benzene assay exhibited a broad linear range of 1–4000 ppm, with a limit of detection of 0.7 ppm, which was below the standard permitted concentrations. Furthermore, the gas sensor system showed outstanding selectivity for benzene compared with seven other types of common volatile organic compounds (VOCs). The proposed gas sensor showed good characteristics with high selectivity, fast response time and long lifetime, which suggested the promising application of the Au/La2O3 nanomaterials as a novel highly efficient CTL‐sensing material. Copyright © 2013 John Wiley & Sons, Ltd.
The effects of experimental conditions of fluorescence quenching on the binding parameters of apigenin to bovine serum albumin by response surface methods
Authors: Tang Lin , Jia Wanteng , Zhang Dong
Published: July 2013

A fluorescence quenching technique is often used to study interactions between small molecules and serum albumin. However, the results are quite different by using spectroscopic techniques on the same drug‐protein interaction research and they may be affected by different conditions (e.g. working solution of pH and ionic strength). In this research, using apigenin as an example, the effect of experimental conditions of fluorescence quenching on the binding parameters of drug to bovine serum albumin was investigated using a response surface method (RSM). The effect of pH, the concentration of NaCl and the concentration Mg2+ on the quenching constant (KSV), the apparent association constant (Ka) and the number of binding sites (n) was studied by single‐factor experiments with pH, [NaCl] and [Mg2+] as independent variables and KSV, Ka and n as response values. Prediction models were fit to a quadratic polynomial regression equation and the results showed that both KSV and n displayed a second‐order model, whereas Ka displayed linear relation dependence on pH, [NaCl] and [Mg2+]. Under these experimental conditions, [NaCl] was the most significant (p < 0.05) impact factor on KSV and Ka, whereas n was most affected by pH (p < 0.05). Copyright © 2013 John Wiley & Sons, Ltd.
Development of a highly sensitive chemiluminescent assay for hydrogen peroxide under neutral conditions using acridinium ester and its application to an enzyme immunoassay
Authors: Arakawa Hidetoshi , Tsuruoka Keiko , Ohno Ken‐ichi , Tajima Noriko , Nagano Hiromi
Published: July 2013

We developed a highly sensitive chemiluminescent (CL) assay for hydrogen peroxide using 10‐methyl‐9‐(phenoxycarbonyl) acridinium fluorosulfonate (PMAC) that produced chemiluminescence under neutral conditions and applied it to an enzyme immunoassay (EIA). One picomole of hydrogen peroxide could be detected using the optimized PMAC‐CL method and 6.2 × 10‐20 mol β‐d‐galactosidase (β‐gal) could be detected by combining an indoxyl derivative substrate and the proposed PMAC‐CL method. This highly sensitive CL β‐gal assay was applied to an EIA for thyroid‐stimulating hormone (TSH) using β‐gal as a label enzyme; 0.02–100.0 μU/mL TSH in human serum could be assayed directly and with high reproducibility. Copyright © 2013 John Wiley & Sons, Ltd.
Structural and luminescence properties of Y2‐xGeMoO8:REx (RE = Eu, Tb) phosphors
Authors: Li Naixu , Zhou Jiancheng , Sun Yueming
Published: July 2013

Y2‐xGeMoO8:REx (RE = Eu, Tb) phosphors were synthesized using a facile sol–gel method. The morphology and structure of the phosphors were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM) and X‐ray diffraction (XRD); while their luminescent properties were investigated by photoluminescence (PL) spectrometry. Our results reveal that all of these Y2‐xGeMoO8:REx (RE = Eu, Tb) phosphors adopted the tetragonal phase, belonging to Scheelite (CaWO4) structure. The obtained YGeMoO8:Eu phosphors exhibit a strong emission in the red light range which can be assigned to the 5D0 → 7F2 transition of Eu3+ when it is excited at 459 nm. Under 392 and 489 nm excitation, the YGeMoO8:Tb phosphors present predominant green emission (5D4 → 7F5) at 540 nm. The highest emission of the phosphors can be achieved by adjusting the doping concentration to be 0.25 for Eu3+ and 0.15 for Tb3+, respectively. The promising luminescence properties of these materials indicate that they can be potentially applied to white‐light‐emitting diodes. Copyright © 2013 John Wiley & Sons, Ltd.
Kinetic isotope effects significantly influence intracellular metabolite 13C labeling patterns and flux determination
Authors: Wasylenko Thomas M. , Stephanopoulos Gregory
Published: July 2013

Rigorous mathematical modeling of carbon‐labeling experiments allows estimation of fluxes through the pathways of central carbon metabolism, yielding powerful information for basic scientific studies as well as for a wide range of applications. However, the mathematical models that have been developed for flux determination from 13C labeling data have commonly neglected the influence of kinetic isotope effects on the distribution of 13C label in intracellular metabolites, as these effects have often been assumed to be inconsequential. We have used measurements of the 13C isotope effects on the pyruvate dehydrogenase enzyme from the literature to model isotopic fractionation at the pyruvate node and quantify the modeling errors expected to result from the assumption that isotope effects are negligible. We show that under some conditions kinetic isotope effects have a significant impact on the 13C labeling patterns of intracellular metabolites, and the errors associated with neglecting isotope effects in 13C‐metabolic flux analysis models can be comparable in size to measurement errors associated with GC–MS. Thus, kinetic isotope effects must be considered in any rigorous assessment of errors in 13C labeling data, goodness‐of‐fit between model and data, confidence intervals of estimated metabolic fluxes, and statistical significance of differences between estimated metabolic flux distributions.
The Conformation of a Ribose Derivative in Aqueous Solution: A Neutron‐Scattering and Molecular Dynamics Study
Authors: Mason Philip E. , Neilson George W. , Saboungi Marie‐Louise , Brady John W.
Published: July 2013

The structure of aqueous solutions of methyl β‐d‐ribofuranoside was investigated by coupling molecular dynamics (MD) simulations and neutron scattering measurements with isotopic substitution. Using a sample of the sugar isotopically‐labeled at a single unique position, neutron scattering structure factors and radial distribution functions can be compared with MD simulations constrained to different conformations to determine which conformer best fits the experimental results. Three different simulations were performed with the methyl ether group of the sugar unconstrained and constrained in each of its staggered orientations. The results of the unconstrained simulation showed that the methyl ester group occupied predominantly the 300° position, which is in agreement with the diffraction experimental results. This result suggests that the molecular mechanics force field used in the simulation adequately describes the conformation of the 1‐methyl ether group in the methyl β‐d‐ribofuranoside. © 2013 Wiley Periodicals, Inc. Biopolymers 99: 739–745, 2013.
Strategies for profiling native S‐nitrosylation
Authors: Majmudar Jaimeen D. , Martin Brent R.
Published: July 2013

Cysteine is a uniquely reactive amino acid, capable of undergoing both nucleophlilic and oxidative post‐translational modifications. One such oxidation reaction involves the covalent modification of cysteine via the gaseous second messenger nitric oxide (NO), termed S‐nitrosylation (SNO). This dynamic post‐translational modification is involved in the redox regulation of proteins across all phylogenic kingdoms. In mammals, calcium‐dependent activation of NO synthase triggers the local release of NO, which activates nearby guanylyl cyclases and cGMP‐dependent pathways. In parallel, diffusible NO can locally modify redox active cellular thiols, functionally modulating many redox sensitive enzymes. Aberrant SNO is implicated in the pathology of many diseases, including neurodegeneration, inflammation, and stroke. In this review, we discuss current methods to label sites of SNO for biochemical analysis. The most popular method involves a series of biochemical steps to mask free thiols followed by selective nitrosothiol reduction and capture. Other emerging methods include mechanism‐based phosphine probes and mercury enrichment chemistry. By bridging new enrichment approaches with high‐resolution mass spectrometry, large‐scale analysis of protein nitrosylation has highlighted new pathways of oxidative regulation. © 2013 Wiley Periodicals, Inc. Biopolymers 101: 173–179, 2014.
Structural biology computing: Lessons for the biomedical research sciences
Authors: Morin Andrew , Sliz Piotr
Published: July 2013

The field of structural biology, whose aim is to elucidate the molecular and atomic structures of biological macromolecules, has long been at the forefront of biomedical sciences in adopting and developing computational research methods. Operating at the intersection between biophysics, biochemistry, and molecular biology, structural biology's growth into a foundational framework on which many concepts and findings of molecular biology are interpreted1 has depended largely on parallel advancements in computational tools and techniques. Without these computing advances, modern structural biology would likely have remained an exclusive pursuit practiced by few, and not become the widely practiced, foundational field it is today. As other areas of biomedical research increasingly embrace research computing techniques, the successes, failures and lessons of structural biology computing can serve as a useful guide to progress in other biomedically related research fields. © 2013 Wiley Periodicals, Inc. Biopolymers 99: 809–816, 2013.
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

Objective

To overview the scientific data and the technical details regarding percutaneous coronary interventions (PCI) on chronic total occlusions (CTO) by radial approach.

Background

Trans‐femoral approach is commonly regarded as the standard for PCI on CTO.

Methods

A 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.

Results

No 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.

Conclusions

The 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.
Transcatheter left ventricular outflow tract stent placement in a low birth weight child with hypoplastic left ventricle, mitral atresia, transposition of the great arteries, ventricular septal defect and severe pulmonary stenosis
Authors: McMahon Colin J. , Morgan Conall T. , Walsh Kevin P.
Published: July 2013

A baby boy, the first of triplets born at 33 weeks gestation weighing 1.88 kg, presented with neonatal cyanosis and was diagnosed with mitral atresia, hypoplastic left ventricle, ventricular septal defect, d‐transposition of the great arteries, severe pulmonary stenosis, and hypoplastic branch pulmonary arteries. He was treated with prostaglandin until seven weeks of age. The patent ductus arteriosus was curly Q and not suitable for stent placement. Cardiac catheterization was undertaken and using an antegrade approach, a Multi‐Link Ultra stent was implanted across the left ventricular outflow tract (LVOT) and inflated to 5 mm to improve antegrade pulmonary blood flow. This allowed reasonable pulmonary arterial growth to allow the patient undergo bidirectional Glenn shunt at five months of age. This first report of LVOT stenting in this setting may provide an alternative to placement of a systemic to pulmonary arterial shunt when ductal stenting is not possible. © 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

Crystalline 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

Rotating‐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

In 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

A 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

Due 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

This 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

An 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

A 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

A 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

Designated 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.
Effect of the preparation method on the structural and magnetic properties of the Fe2Nb alloy
Authors: Vélez G. Y. , Alcázar G. A. Pérez , Zamora Ligia E. , Tabares J. A.
Published: July 2013

In this paper we carried out the structural and magnetic study of the Fe2Nb stoichiometric alloy by means of x‐rays diffraction and Mössbauer spectrometry. The samples were obtained by two different techniques, arc‐melting and mechanical alloying, and then they were thermally treated. The structural properties of the alloy depend on the method of preparation: by the melting method it was possible to obtain the hcp‐Fe2Nb ordered structure; while by mechanical alloying besides of the hcp structure also were formed the fcc‐NbO and bcc‐FeNb structures. After heat treatment of the melted alloy, this was submitted to mechanical alloying during 16 and 32 hours. Mechanical alloying allows the formation of bcc‐FeNb grains which behave as superparamagnetic due to their small size and they are surrounded by hcp grains. Before heat treatment of the alloy obtained by mechanical alloying it was also found the existence of superparamagnetic bcc grains and the heat treatment increases the size of these bcc grains and the superparamagnetic‐ferromagnetic transition is induced.
Combination of colored patterns and cubes for crystallographic point group visualization
Authors: Nolze Gert
Published: July 2013

A concept based on the application of a cube as a general polyhedron is presented for the visualization of point group symmetry. The cube is used to represent both the highest and lowest crystal symmetries, with differences observable as patterns characteristic to each point group. Patterns are generated using direction‐specific color keys, which enable the recognition of point group‐specific distribution of vectors in an external reference frame. For the visualization of the incoherent hexagonal crystal classes, two twinned cubes are applied in order to generate symmetry operators that would otherwise be missing. The resulting hexagonal dipyramid is described in the frame of a cube, reducing the number of used symmetry operators from 72 to 60. The complete set of 32 polyhedra are suitable, for example, as a visual aid for understanding the crystal symmetry and/or sub‐ and supergroup relationships.
The microstructure and magnetic property of TiO2‐terminated SrTiO3 substrate selected growth cubic phase CaRuO3 film
Authors: Zhang Lunyong , Zhou Jian , Zhang Shan‐Tao , Chen Y. B. , Chen Yan‐Feng
Published: July 2013

CaRuO3 thin films with various thicknesses were synthesized by pulsed laser deposition respectively on SrTiO3 substrates with SrO‐ and TiO2‐termination. The microstructure of these films was studied by transmission electron microscopy. The results demonstrate that the CaRuO3 thin films grown on TiO2‐terminated substrates show quite uniform morphology, whilst they do the facet morphology when the substrates are SrO‐terminated. In addition, there is a 5∼7 unit‐cell‐thickness cubic CaRuO3 layer in the films grown on TiO2‐terminated substrates. The measured ferromagnetic hysteresis loop is attributed to the cubic CaRuO3 layer, which is supported by a first‐principles calculations. On the contrary, there is free of cubic CaRuO3 layer in samples grown on SrO‐terminated substrates. The crystallographic domains, the orientation relationship between domains and substrates and crystal defects in these films were studied as well. The different growth mechanism of CaRuO3 on SrO‐ and TiO2‐terminated SrTiO3 substrates may be correlated with the selective nucleation and growth.
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

Invited 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
Hox genes regulation in vertebrates
Authors: Soshnikova Natalia
Published: July 2013

Hox genes encode transcription factors defining cellular identities along the major and secondary body axes. Their coordinated expression in both space and time is critical for embryonic patterning. Accordingly, Hox genes transcription is tightly controlled at multiple levels, and involves an intricate combination of local and long‐range cis‐regulatory elements. Recent studies revealed that in addition to transcription factors, dynamic patterns of histone marks and higher‐order chromatin structure are important determinants of Hox gene regulation. Furthermore, the emerging picture suggests an involvement of various species of non‐coding RNA in targeting activating and repressive complexes to Hox clusters. I review these recent developments and discuss their relevance to the control of Hox gene expression in vivo, as well as to our understanding of transcriptional regulatory mechanisms. Developmental Dynamics 243:49–58, 2014. © 2013 Wiley Periodicals, Inc.
Complex cardiac defects after ethanol exposure during discrete cardiogenic events in zebrafish: Prevention with folic acid
Authors: Sarmah Swapnalee , Marrs James A.
Published: July 2013

Background: Fetal alcohol spectrum disorder (FASD) describes a range of birth defects including various congenital heart defects (CHDs). Mechanisms of FASD‐associated CHDs are not understood. Whether alcohol interferes with a single critical event or with multiple events in heart formation is not known. Results: Our zebrafish embryo experiments showed that ethanol interrupts different cardiac regulatory networks and perturbs multiple steps of cardiogenesis (specification, myocardial migration, looping, chamber morphogenesis, and endocardial cushion formation). Ethanol exposure during gastrulation until cardiac specification or during myocardial midline migration did not produce severe or persistent heart development defects. However, exposure comprising gastrulation until myocardial precursor midline fusion or during heart patterning stages produced aberrant heart looping and defective endocardial cushions. Continuous exposure during entire cardiogenesis produced complex cardiac defects leading to severely defective myocardium, endocardium, and endocardial cushions. Supplementation of retinoic acid with ethanol partially rescued early heart developmental defects, but the endocardial cushions did not form correctly. In contrast, supplementation of folic acid rescued normal heart development, including the endocardial cushions. Conclusions: Our results indicate that ethanol exposure interrupted divergent cardiac morphogenetic events causing heart defects. Folic acid supplementation was effective in preventing a wide spectrum of ethanol‐induced heart developmental defects. Developmental Dynamics 242:1184–1201, 2013. © 2013 Wiley Periodicals, Inc.
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

Food 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

We 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

Do 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.
Peritoneal carcinomatosis of gastric origin: A population‐based study on incidence, survival and risk factors
Authors: Thomassen Irene , van Gestel Yvette R. , van Ramshorst Bert , Luyer Misha D. , Bosscha Koop , Nienhuijs Simon W. , Lemmens Valery E. , de Hingh Ignace H.
Published: July 2013

Peritoneal carcinomatosis (PC) is an important cause of morbidity and mortality among patients with gastric cancer. The aim of the current study was to provide reliable population‐based data on the incidence, risk factors and prognosis of PC of gastric origin. All patients diagnosed with gastric cancer in the area of the Eindhoven Cancer Registry between 1995 and 2011 were included. Incidence and survival were computed and risk factors for peritoneal carcinomatosis were determined using multivariate logistic regression analysis. In total, 5,220 patients were diagnosed with gastric cancer, of whom 2,029 (39%) presented with metastatic disease. PC was present in 706 patients (14%) of whom 491 patients (9%) had PC as the only metastatic site. Younger age (<60 years), female gender, advanced T‐ and N‐stage, primary tumor of signet ring cells or linitis plastica and primary tumors covering multiple anatomical locations of the stomach were all associated with a higher odds ratios of developing PC. Median survival of patients without metastases was 14 months, but only 4 months for patients with PC. PC is a frequent condition in patients presenting with gastric cancer, especially in younger patients with advanced tumor stages. Given the detrimental influence of PC on survival, efforts should be undertaken to further explore the promising results that were obtained in preventing or treating this condition with multimodality strategies.
8‐Oxo‐7,8‐dihydroguanine and uric acid as efficient predictors of survival in colon cancer patients
Authors: Dziaman Tomasz , Banaszkiewicz Zbigniew , Roszkowski Krzysztof , Gackowski Daniel , Wisniewska Ewa , Rozalski Rafał , Foksinski Marek , Siomek Agnieszka , Speina Elzbieta , Winczura Alicja , Marszalek Andrzej , Tudek Barbara , Olinski Ryszard
Published: July 2013

The aim of this work was to answer the question whether the broad range of parameters which describe oxidative stress and oxidatively damaged DNA and repair are appropriate prognosis factors of colon cancer (CRC) patients survival? The following parameters were analyzed for 89 CRC patients: concentration of uric acid and vitamins A, E, C in plasma; levels of 8‐oxodGuo (8‐oxo‐7,8‐dihydro‐2′‐deoxyguanosine) in DNA of leukocyte and colon tissues; urinary excretion rates of 8‐oxodGuo and 8‐oxoGua (8‐oxo‐7,8‐dihydroguanine); the activity and mRNA or protein level of repair enzymes OGG1, APE1, ANPG, TDG and PARP1. All DNA modifications and plasma antioxidants were analyzed using high performance liquid chromatography (HPLC) or HPLC/gas chromatography‐mass spectrometry techniques. Expression of repair proteins was analyzed by QPCR, Western or immunohistochemistry methods. Longer survival coincided with low levels of 8‐oxodGuo/8oxoGua in urine and 8‐oxodGuo in DNA as well as with high concentration of uric acid plasma level. In contrast to expectations, longer survival coincided with lower mRNA level in normal colon tissue of the main 8‐oxoGua DNA glycosylase, OGG1, but no association was found for PARP‐1 expression. When analyzing simultaneously two parameters the discriminating power increased significantly. Combination of low level of urinary 8‐oxoGua together with low level of 8‐oxodGuo in leukocyte (both below median value) or high concentration of plasma uric acid (above median value) have the best prediction power. Since prediction value of these parameters seems to be comparable to conventional staging procedure, they could possibly be used as markers to predict clinical success in CRC treatment.
The Wilms' tumor suppressor WT1 enhances CD95L expression and promotes activation‐induced cell death in leukemic T cells
Authors: Bourkoula Konstantina , Englert Christoph , Giaisi Marco , Köhler Rebecca , Krammer Peter H. , Li‐Weber Min
Published: July 2013

The role of Wilms' tumor suppressor 1 (WT1) in leukemogenesis has been investigated mostly in acute (AML) and chronic (CML) myeloid leukemias. So far, its oncogenic role has been controversially discussed because both overexpression and inactivating mutations are found. A recent study on primary samples from patients with acute T‐cell leukemia (T‐ALL) revealed that most of them do not express WT1 proteins although they express WT1 mRNA. In our study, we investigated WT‐1 expression in ten T‐ALL cell lines established from leukemia/lymphoma patients. We show that consistent with the finding in primary T‐ALL cells, most of the leukemic T‐cell lines tested do not overexpress WT1 proteins. We found that leukemic T‐cells overexpressing WT1 protein produce higher levels of CD95L and show elevated CD95L‐mediated activation‐induced cell death (AICD) compared to cells lacking or expressing low levels of WT1. Ectopic expression of WT1 in the WT1‐nonexpressing leukemic T‐cell line increases CD95L expression and elevates activation‐induced apoptosis, whereas silencing WT1 expression in the WT1‐overexpressing leukemic T‐cell line by siRNA confers reduced CD95L expression and reduction in AICD. Chromatin immunoprecipitation and luciferase‐promoter reporter analysis demonstrate that WT1 binds to and enhances CD95L promoter activity through the Egr‐binding sites. Our study provides a new role of WT1 in regulation of CD95L‐mediated cell death.
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

Objectives

The 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.

Methods

Eighty 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.

Results

Of 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).

Conclusions

US‐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;
Barrow Canyon volume, heat, and freshwater fluxes revealed by long‐term mooring observations between 2000 and 2008
Authors: Itoh Motoyo , Nishino Shigeto , Kawaguchi Yusuke , Kikuchi Takashi
Published: July 2013

Barrow Canyon, in the northeast Chukchi Sea, is a major conduit for Pacific Water to enter the interior Arctic basins. Assemblies of annual (September 2000 to August 2008) temperature, salinity, and velocity data acquired from a mooring array in the mouth of Barrow Canyon and high‐resolution hydrographic and velocity transects along the mooring array in 2002, 2010, and 2011 have enabled a direct computation of volume, heat, and freshwater fluxes. Annual mean volume transport through Barrow Canyon was 0.45 Sv, which consisted of 0.44 Sv of Pacific Water and 0.01 Sv of Atlantic Water. Annual mean Pacific Water transport through Barrow Canyon represents 55% of the long‐term mean Pacific Water inflow through the Bering Strait. During summer, more of the Pacific inflow was advected to an eastern path as the Alaskan Coastal Current that flows along the Alaskan coast to Barrow Canyon. The freshwater flux through Barrow Canyon was 904 km3/yr, which is equivalent to 5% of the freshwater content of the Canada Basin. The annual averaged heat flux displayed substantial interannual variability, ranging from 0.93 to 3.02 TW, which could melt 88,000–290,000 km2 of 1 m thick ice. A relationship exists between the measured Barrow Canyon transport and local winds such that under southerly winds the northward flow of water through the canyon increases. Such wind conditions are induced by the weaker sea level pressure contrast between the Arctic and North Pacific, caused by a decrease in the pressure over the Arctic and an increase over the North Pacific.