bluuebunny/crossref_metadata_2025_split huggingface dataset:
High‐Performance of Gas Hydrates in Confined Nanospace for Reversible CH4/CO2 Storage
Authors: Casco Mirian E. , Jordá José L. , Rey Fernando , Fauth François , Martinez‐Escandell Manuel , Rodríguez‐Reinoso Francisco , Ramos‐Fernández Enrique V. , Silvestre‐Albero Joaquín 
Published: June 2016

AbstractThe molecular exchange of CH4 for CO2 in gas hydrates grown in confined nanospace has been evaluated for the first time using activated carbons as a host structure. The nano‐confinement effects taking place inside the carbon cavities and the exceptional physicochemical properties of the carbon structure allows us to accelerate the formation and decomposition process of the gas hydrates from the conventional timescale of hours/days in artificial bulk systems to minutes in confined nanospace. The CH4/CO2 exchange process is fully reversible with high efficiency at practical temperature and pressure conditions. Furthermore, these activated carbons can be envisaged as promising materials for long‐distance natural gas and CO2 transportation because of the combination of a high storage capacity, a high reversibility, and most important, with extremely fast kinetics for gas hydrate formation and release.
Redox‐Active Tetraruthenium Macrocycles Built from 1,4‐Divinylphenylene‐Bridged Diruthenium Complexes
Authors: Scheerer Stefan , Linseis Michael , Wuttke Evelyn , Weickert Sabrina , Drescher Malte , Tröppner Oliver , Ivanović‐Burmazović Ivana , Irmler Andreas , Pauly Fabian , Winter Rainer F. 
Published: June 2016

AbstractMetallamacrocylic tetraruthenium complexes were generated by treatment of 1,4‐divinylphenylene‐bridged diruthenium complexes with functionalized 1,3‐benzene dicarboxylic acids and characterized by HR ESI‐MS and multinuclear NMR spectroscopy. Every divinylphenylene diruthenium subunit is oxidized in two consecutive one‐electron steps with half‐wave potential splittings in the range of 250 to 330 mV. Additional, smaller redox‐splittings between the +/2+ and 0/+ and the 3+/4+ and 2+/3+ redox processes, corresponding to the first and the second oxidations of every divinylphenylene diruthenium entity, are due to electrostatic effects. The lack of electronic coupling through bond or through space is explained by the nodal properties of the relevant molecular orbitals and the lateral side‐by‐side arrangement of the divinylphenylene linkers. The polyelectrochromic behavior of the divinylphenylene diruthenium precursors is retained and even amplified in these metallamacrocyclic structures. EPR studies down to T=4 K indicate that the dications 1‐H2+ and 1‐OBu2+ are paramagnetic. The dications and the tetracation of macrocycle 3‐H display intense (dications) or weak (3‐H4+) EPR signals. Quantum chemical calculations indicate that the four most stable conformers of the macrocycles are largely devoid of strain. Bond parameters, energies as well as charge and spin density distributions of model macrocycle 5‐HMe were calculated for the different charge and spin states.
Toward Fluorescence‐Based High‐Throughput Screening for Enantiomeric Excess in Amines and Amino Acid Derivatives
Authors: Shcherbakova Elena G. , Brega Valentina , Minami Tsuyoshi , Sheykhi Sara , James Tony D. , Anzenbacher Pavel 
Published: June 2016

AbstractA highly accurate and reliable screening method for enantiomeric excess of amine derivatives in the presence of water is reported. The fluorescence‐based screening system has been realized by self‐assembly of chiral diol‐type dyes (BINOL, VANOL and VAPOL), 2‐formylphenylboronic acid, and chiral amines forming iminoboronate esters. The structure and chirality of the amine analytes determine the stability of the diastereomeric iminoboronate esters, which in turn display differential fluorescence. The fluorescence signal reflects the enantiomeric purity of the chiral amines and was utilized in high‐throughput arrays. The arrays were able to recognize enantiomeric excess of amines, amino esters, and amino alcohols. In addition to qualitative analysis, quantitative experiments were successfully performed. Studies of the role of additives such as water or citrate were carried out to gain insight into the stability of the iminoboronate esters. It is shown that the above additives destabilize less stable esters while the stable esters remain unchanged. Thus, the presence of water and citrate leads to increased difference between the diastereomeric iminoboronates and contributes to the enantiodiscrimination of the chiral amines.
Isolation and Ambident Reactivity of a Chlorogermylenoid
Authors: Suzuki Yuko , Sasamori Takahiro , Guo Jing‐Dong , Nagase Shigeru , Tokitoh Norihiro 
Published: June 2016

AbstractTreatment of 2,5‐di(3,5‐tert‐butylphenyl)‐1‐lithioferrocene with GeCl2⋅dioxane afforded the corresponding chlorogermylenoid that exhibited an ambident reactivity in different solvents; it displayed a behavior characteristic for a dichlorogermylene anion in THF, while it exhibited the typical reactivity of a chlorogermylene in toluene. X‐Ray diffraction analysis of a single crystal of this chlorogermylenoid, obtained from recrystallization in THF, revealed a separated‐ion‐pair structure in the solid state.
A meta‐analysis of the UTAUT model: Eleven years later
Authors: Khechine Hager , Lakhal Sawsen , Ndjambou Paterne 
Published: June 2016

AbstractThe unified theory of acceptance and use of technology (UTAUT) has been widely used to investigate factors influencing the adoption and use of information systems and technologies (IS/IT). However, studies using UTAUT are not conclusive in terms of statistical significance, direction, and magnitude. Through a meta‐analysis of empirical studies on UTAUT from 2003 to 2013, we determine how parsimonious, accurate, and robust UTAUT is at predicting acceptance and use of technology. A meta‐analysis of 74 publications reveals that performance expectancy, effort expectancy, and social influence explain IS/IT adoption, while behavioural intention is the most often measured dependent variable operationalized as a proxy for system use, supporting the strength of UTAUT as an explanatory model of IS/IT acceptance and use. Copyright © 2016 ASAC. Published by John Wiley & Sons, Ltd.
Rapid and reliable diagnosis of Wilson disease using X‐ray fluorescence
Authors: Kaščáková Slávka , Kewish Cameron M. , Rouzière Stéphan , Schmitt Françoise , Sobesky Rodolphe , Poupon Joël , Sandt Christophe , Francou Bruno , Somogyi Andrea , Samuel Didier , Jacquemin Emmanuel , Dubart‐Kupperschmitt Anne , Nguyen Tuan Huy , Bazin Dominique , Duclos‐Vallée Jean‐Charles , Guettier Catherine , Le Naour François 
Published: June 2016

AbstractWilson's disease (WD) is a rare autosomal recessive disease due to mutations of the gene encoding the copper‐transporter ATP7B. The diagnosis is hampered by the variability of symptoms induced by copper accumulation, the inconstancy of the pathognomonic signs and the absence of a reliable diagnostic test. We investigated the diagnostic potential of X‐ray fluorescence (XRF) that allows quantitative analysis of multiple elements. Studies were performed on animal models using Wistar rats (n = 10) and Long Evans Cinnamon (LEC) rats (n = 11), and on human samples including normal livers (n = 10), alcohol cirrhosis (n = 8), haemochromatosis (n = 10), cholestasis (n = 6) and WD (n = 22). XRF experiments were first performed using synchrotron radiation to address the elemental composition at the cellular level. High‐resolution mapping of tissue sections allowed measurement of the intensity and the distribution of copper, iron and zinc while preserving the morphology. Investigations were further conducted using a laboratory X‐ray source for irradiating whole pieces of tissue. The sensitivity of XRF was highlighted by the discrimination of LEC rats from wild type even under a regimen using copper deficient food. XRF on whole formalin‐fixed paraffin embedded needle biopsies allowed profiling of the elements in a few minutes. The intensity of copper related to iron and zinc significantly discriminated WD from other genetic or chronic liver diseases with 97.6% specificity and 100% sensitivity. This study established a definite diagnosis of Wilson's disease based on XRF. This rapid and versatile method can be easily implemented in a clinical setting.
Dynamics of Molecular Crystals by Means of 1H NMR Relaxometry: Dynamical Heterogeneity versus Homogenous Motion
Authors: Kruk Danuta , Florek‐Wojciechowska Małgorzata , Jakubas Ryszard , Chaurasia Sujeet K. , Brym Szczepan 
Published: June 2016

Abstract1H NMR relaxometry was used to reveal information on the dynamical properties of the molecular crystal (PyH)5Bi2Br11 (PyH=C5H6N, pyridinium cation), chosen as an example of a solid that exhibits a complex structure and rotational‐like dynamics. Experimental studies were performed over a very broad frequency range, from 4 kHz to 40 MHz (referring to the 1H resonance frequency) versus temperature. The extensive set of data was thoroughly analyzed in terms of two motional models differing with respect to the assumed mechanism (heterogeneous versus homogenous) of the motion of the PyH cations. A Cole–Davidson distribution of the correlation times describing the assumed motional heterogeneity was tested against a concept of two correlation times characterizing the rotation‐like dynamics of the PyH cation around the perpendicular axes differing by about one order of magnitude. The parameters describing the dynamics of the cation, obtained by means of both models, were compared and discussed.
DFT‐Based Simulation and Experimental Validation of the Topotactic Transformation of MgAl Layered Double Hydroxides
Authors: Zhang Shi‐Tong , Dou Yibo , Zhou Junyao , Pu Min , Yan Hong , Wei Min , Evans David G. , Duan Xue 
Published: June 2016

AbstractThe thermal topotactic transformation mechanism of MgAl layered double hydroxides (LDHs) is investigated by a combined theoretical and experimental study. Thermogravimetric differential thermal analysis (TG‐DTA) results reveal that the LDH phase undergoes four key endothermic events at 230, 330, 450, and 800 °C. DFT calculations show that the LDH decomposes into CO2 and residual O atoms via a monodentate intermediate at 330 °C. At 450 °C, the metal cations almost maintain their original distribution within the LDH(001) facet during the thermal dehydration process, but migrate substantially along the c‐axis direction perpendicular to the (001) facet; this indicates that the metal arrangement/dispersion in the LDH matrix is maintained two‐dimensionally. A complete collapse of the layered structure occurs at 800 °C, which results in a totally disordered cation distribution and many holes in the final product. The structures of the simulated intermediates are highly consistent with the observed in situ powder XRD data for the MgAl LDH sample calcined at the corresponding temperatures. Understanding the structural topotactic transformation process of LDHs would provide helpful information for the design and preparation of metal/metal oxides functional materials derived from LDH precursors.
Ordered Mesoporous Polyoxometalate–Organosilica Frameworks as Efficient Photocatalysts of the Hydrogen Evolution Reaction
Authors: Koutsouroubi Eirini D. , Papadas Ioannis T. , Armatas Gerasimos S. 
Published: June 2016

AbstractPolyoxometalate clusters have been recently established as promising nanomaterials for photocatalytic water splitting. Here, the synthesis is reported of mesoporous polymers composed of a 3D porous network of lacunary [XM11O39]q− (XM11; X=P, Si; M=W, Mo) polyoxometalate units connected by ethano‐bridged silsesquioxane linkers through a block copolymer‐templated crosslinking polymerization of 1,2‐bis(triethoxysilyl)ethane in acidic solution. The resulting materials feature an ordered mesostructured ethane–silica (MES) framework that hosts a high density of accessible polyoxometalate clusters, which allows for efficient catalytic reactions. XM11/MES hybrid polymers have a relatively high activity for the hydrogen evolution reaction with remarkable cycle stability under UV/Vis light irradiation (λ>360 nm), without the need for co‐catalysts or additional photosensitizers. It is also shown that the photocatalytic efficiency of these materials arises from the nanoscale pore structure, high surface area and chemical manipulation of the electronic band structure of constituting heteropolyoxo clusters.
Artificial Hydrogenases Based on Cobaloximes and Heme Oxygenase
Authors: Bacchi Marine , Veinberg Elias , Field Martin J. , Niklas Jens , Matsui Toshitaka , Tiede D. M. , Poluektov Oleg G. , Ikeda‐Saito Masao , Fontecave Marc , Artero Vincent 
Published: June 2016

AbstractThe insertion of cobaloxime catalysts in the heme‐binding pocket of heme oxygenase (HO) yields artificial hydrogenases active for H2 evolution in neutral aqueous solutions. These novel biohybrids have been purified and characterized by using UV/visible and EPR spectroscopy. These analyses revealed the presence of two distinct binding conformations, thereby providing the cobaloxime with hydrophobic and hydrophilic environments, respectively. Quantum chemical/molecular mechanical docking calculations found open and closed conformations of the binding pocket owing to mobile amino acid residues. HO‐based biohybrids incorporating a {Co(dmgH)2} (dmgH2=dimethylglyoxime) catalytic center displayed up to threefold increased turnover numbers with respect to the cobaloxime alone or to analogous sperm whale myoglobin adducts. This study thus provides a strong basis for further improvement of such biohybrids, using well‐designed modifications of the second and outer coordination spheres, through site‐directed mutagenesis of the host protein.
Quantification methods for human and large animal leukocytes using DNA dyes by flow cytometry
Authors: Pieper Ina Laura , Radley Gemma , Chan Chris H. H. , Friedmann Yasmin , Foster Graham , Thornton Catherine A. 
Published: June 2016

AbstractOvine and bovine blood is used heavily within the development of blood‐handling medical devices, such as heart pumps (left ventricular assist devices, LVADs), for which blood cell damage needs to be monitored during in vitro testing. Hematology analyzers provide cell counts but no information about cell viability. The anthraquinone DNA dyes CyTRAK Orange™ and DRAQ7™ have practical and spectral properties rendering them suitable for multicolor assays. Compared to other DNA dyes such as Vybrant Dyecycle, CyTRAK Orange enables a faster staining protocol and does not require incubation at +37°C. Compared to traditional viability dyes such as propidium iodide and 7AAD, DRAQ7's unique spectral profile of excitation in both blue and red lasers and far‐red emission enables identification of dual positive dead cell events and frees up detectors for use with other reagents. CyTRAK Orange and DRAQ7 could be used in combination with absolute counting bead standards to provide cell counts and viability but the combination of these dyes has previously only been used for microscopy on rodent cells. The purpose of this study was to evaluate the use of these dyes in combination in large animal blood samples for flow cytometry. A viability and cell counting protocol for bovine, ovine, and human leukocytes using CyTRAK Orange and DRAQ7 was prepared. Four different counting bead standards were evaluated using the Navios and FACSAria cytometers and compared to counts obtained from hematology analyzers. CyTRAK Orange successfully detected CD45+leukocytes in all species. The DRAQ7 single‐stained dead cell counts correlated well with the CyTRAK Orange/DRAQ7 double‐stained dead cell counts in human and bovine blood, but not in ovine blood, which could be related to the blood source. In conclusion, for human and bovine blood, this method works well for viability counts using different flow cytometers and bead standards. © 2016 International Society for Advancement of Cytometry
Application of image cytometry to characterize heterologous lipid flippases in yeast
Authors: Jensen Maria S. , Costa Sara R. , Theorin Lisa , Christensen Jan Pravsgaard , Pomorski Thomas Günther , López‐Marqués Rosa L. 
Published: June 2016

AbstractLipid flippases are integral membrane proteins that play a central role in moving lipids across cellular membranes. Some of these transporters are ATPases that couple lipid translocation to ATP hydrolysis, whereas others function without any discernible metabolic energy input. A growing number of lipid flippases has been identified but key features of their activity remain to be elucidated. A well‐established method to characterize ATP‐driven flippases is based on their heterologous expression in yeast, followed by incubation of the cells with fluorescent lipids. Internalization of these probes is typically monitored by flow cytometry, a costly and maintenance‐intensive method. Here, we have optimized a protocol to use an automated image‐based cell counter to accurately measure lipid uptake by heterologous lipid flippases expressed in yeast. The method was validated by comparison with the classical flow cytometric evaluation of lipid‐labeled cells. In addition, we demonstrated that expression of fluorescently tagged flippase complexes can be directly co‐related with fluorescent lipid uptake using the image‐based cell counter system. The method extends the number of techniques available for characterization of lipid flippase activity, and should be readily adaptable to analyze a variety of other transport systems in yeast, parasites, and mammalian cells. © 2016 International Society for Advancement of Cytometry
Masonry buildings at the borderline to high‐rise – Part 2 / Mauerwerksbauten an der Hochhausgrenze – Teil 2
Authors: Seim Werner , Sommerlade Kai 
Published: June 2016

AbstractFor the verification of framing shear walls of masonry, the decisive combination of actions derives from the interaction of vertical and horizontal actions. In this article, a method based on simple truss models is extended for the transfer of horizontal actions. It is demonstrated how the required verifications of load‐bearing safety can be performed with the results of the structural calculation. As an example, the application of the method for a seven‐storey building with calcium silicate blockwork or Poroton brick masonry is described.
Analysis of steel‐reinforced masonry walls regarding maximum shear loads / Traglastberechnung von vertikal bewehrten Mauerwerksscheiben
Authors: Stempfle Hartwig , Weber Marius , Wipfli Manuel 
Published: June 2016

AbstractLoadings on masonry for the earthquake case pose particular challenges for the material. In order to improve the load‐bearing and deformation behaviour, masonry building elements can be strengthened with reinforcement. This article presents an analytical model for the calculation of the load‐bearing capacity of vertically reinforced masonry panels. The masonry is modelled as a homogeneous and anisotropic material and failure conditions are based on the plastic theory. Using uniaxially loaded stress fields and considering the structural constraints, a lower load‐bearing threshold can be given. In order to verify the model, three shear tests on reinforced sand‐lime block masonry were recalculated regarding their load‐bearing capacity. The test panels each contained vertical steel reinforcement in the blocks. The blocks were laid in thin bed mortar.
Long‐term impacts of dam construction on plant succession and survival of an endangered species
Authors: Lucas S. D. , Wheeler J. A. , Atallah Y. C. , Walker S. E. , Jones C. E. , Burk J. H. 
Published: June 2016

AbstractThis study was conducted to determine what changes have occurred in an arid alluvial riparian shrub habitat in the upper Santa Ana River basin over a 20+‐yr period beginning prior to the completion of the Seven Oaks Dam in San Bernardino County, California and continuing until 8 yr after the completion of the dam in 2000 to assess the implications any changes may have on the persistence of the short‐lived Santa Ana River Woolly Star (Eriastrum densifolium ssp. sanctorum, Polemoniaceae). Small‐scale habitat changes were determined by comparing non‐native annual plant data from 1989 to 2008. Large‐scale habitat changes were determined by comparing perennial plant data from 1987 to 2008. The results of this study suggest that annual species, lichen crust, and dead shrubs are increasing, and that bare ground and live shrubs are decreasing. The older sites are also increasing in annual grass cover. Successional changes have occurred since the last significant flood event in 1969 although these changes are gradual and on a continuum, precluding a sharp distinction between different age stages. The data support previously predicted rates of succession indicating ultimate maturity within at least 100 yr. The continuation of these habitat changes will likely contribute to the decline of the Woolly Star population, particularly during future drought periods.
A spatially‐explicit assessment of the fish population response to flow management in a heterogeneous landscape
Authors: Guénard Guillaume , Lanthier Gabriel , Harvey‐Lavoie Simonne , Macnaughton Camille J. , Senay Caroline , Lapointe Michel , Legendre Pierre , Boisclair Daniel 
Published: June 2016

AbstractEcological processes are structured in space and there are important benefits in incorporating spatial information for the analysis of data sets obtained from field studies. Assessing the effect of different flow management practices on river ecosystems is an example where such an exercise is highly relevant. Human activities such as hydroelectric power production are known to modify the temporal variability in river flow. Flow management strategies may have a direct influence on fishes and may trigger complex cascades of interactions involving different features of the river ecosystem. In this study, we performed an assessment of the effect of different flow management practices on fish count density (no. fish/m2), biomass density (g/m2), and species richness. Data were collected in 941 sites located along 28 Canadian rivers. These rivers were either naturally flowing or had altered flows from one of three flow management strategies: run of the river dams, storage with gradual release, or storage with peak release. Each site (300 m2) was surveyed using paired snorkeling and electrofishing techniques; environmental variables (water depth and velocity, and substrate composition) were also measured. The study spanned a broad geographic range (3497 km, geodesic distance) and involved repeated local observations (16–50 sites/river), and was therefore inherently spatially organized. We used spatial modeling to obtain a baseline to estimate the effect of flow management strategies on fishes. Our results indicate that rivers downstream of flow peaking storage dams have, by far, the lowest fish densities (count and biomass) and species richness, whereas those downstream of gradual release storage dams had higher fish biomass density than the unregulated rivers.