bluuebunny/crossref_metadata_2025_split huggingface dataset:
Feeding the “aneurysm”: Orogen‐parallel mass transport into Nanga Parbat and the western Himalayan syntaxis
Authors: Whipp David M. , Beaumont Christopher , Braun Jean 
Published: May 2014

AbstractThe Nanga Parbat‐Haramosh massif (NPHM; western Himalayan syntaxis) requires an influx of mass exceeding that in the adjacent Himalayan arc to sustain high topography and rapid erosional exhumation rates. What supplies this mass flux and feeds this “tectonic aneurysm?” We show, using a simple 3‐D model of oblique orogen convergence, that velocity/strain partitioning results in horizontal orogen‐parallel (OP) crustal transport, and the same behavior is inferred for the Himalaya, with OP transport diverting converging crust toward the syntaxis. Model results also show that the OP flow rate decreases in the syntaxis, thereby thickening the crust and forming a structure like the NPHM. The additional crustal thickening, over and above that elsewhere in the Himalayan arc, sustains the rapid exhumation of this “aneurysm.” Normally, velocity/strain partitioning would be minimal for the Himalayan arc where the convergence obliquity is no greater than ~40°. However, we show analytically that the Himalayan system can act both as a critical wedge and exhibit strain partitioning if both the detachment beneath the wedge and the bounding rear shear zone, which accommodates OP transport, are very weak. Corresponding numerical results confirm this requirement and demonstrate that a Nanga Parbat‐type shortening structure can develop spontaneously if the orogenic wedge and bounding rear shear zone can strain rate soften while active. These results lead us to question whether the position of NPHM aneurysm is localized by river incision, as previously suggested, or by a priori focused tectonic shortening of the crust in the syntaxis region as demonstrated by our models.
Stick‐slip and creep behavior in lubricated granular material: Insights into the brittle‐ductile transition
Authors: Reber Jacqueline E. , Hayman Nicholas W. , Lavier Luc L. 
Published: May 2014

AbstractCrustal deformation can occur via stick‐slip events, viscous creep, or strain transients at variable rates. Here we explore such strain transients with physical experiments comprising a quasi‐two‐dimensional shear zone with elastic, acrylic discs and interstitial viscous silicone. Experiments of solely elastic discs produce stick‐slip events and an overall (constant volume) strengthening. The addition of the viscous silicone enhances localization but does not greatly change the overall pattern of strengthening. It does, however, damp the stick‐slip events, leading to transient, creep‐like behavior that approaches the behavior of a Maxwell body. There is no gradual transition from frictional to viscous deformation with increasing amounts of silicone, suggesting that the mixed rheology is in effect as soon as an interstitial fluid is present. Our experiments support the hypothesis that a possible cause for strain transients in nature is an interstitial viscous phase in shear zones.
Exploring the cross correlations and autocorrelations of the ULF indices and incorporating the ULF indices into the systems science of the solar wind‐driven magnetosphere
Authors: Borovsky Joseph E. , Denton Michael H. 
Published: May 2014

AbstractThe ULF magnetospheric indicesSgr,Sgeo,Tgr, andTgeoare examined and correlated with solar wind variables, geomagnetic indices, and the multispacecraft‐averaged relativistic‐electron fluxFin the magnetosphere. The ULF indices are detrended by subtracting off sine waves with 24 h periods to formSgrd,Sgeod,Tgrd, andTgeod. The detrending improves correlations. Autocorrelation‐function analysis indicates that there are still strong 24 h period nonsinusoidal signals in the indices which should be removed in future. Indications are that the ground‐based indicesSgrdandTgrdare more predictable than the geosynchronous indicesSgeodandTgeod. In the analysis, a difference index ∆Smag ≈ Sgrd− 0.693Sgeodis derived: the time integral of ∆Smaghas the highest ULF index correlation with the relativistic‐electron fluxF. In systems‐science fashion, canonical correlation analysis (CCA) is used to correlate the relativistic‐electron flux simultaneously with the time integrals of (a) the solar wind velocity, (b) the solar wind number density, (c) the level of geomagnetic activity, (d) the ULF indices, and (e) the type of solar wind plasma (coronal hole versus streamer belt): The time integrals of the solar wind density and the type of plasma have the highest correlations withF. To create a solar wind‐Earth system of variables, the two indicesSgrdandSgeodare combined with seven geomagnetic indices; from this, CCA produces a canonical Earth variable that is matched with a canonical solar wind variable. Very high correlations (rcorr = 0.926) between the two canonical variables are obtained.
Altering the Substrate Specificity of Reductase CgKR1 from Candida glabrata by Protein Engineering for Bioreduction of Aromatic α‐Keto Esters
Authors: Huang Lei , Ma Hong‐Min , Yu Hui‐Lei , Xu Jian‐He 
Published: May 2014

AbstractA versatile keto ester reductase CgKR1, exhibiting a broad substrate spectrum, was obtained from Candida glabrata by genome data mining. It showed the highest activity toward an aliphatic β‐keto ester, ethyl 4‐chloro‐3‐oxobutanoate (COBE), but much lower activity toward bulkier α‐keto esters with an aromatic group, such as methyl ortho‐chlorobenzoylformate (CBFM) and ethyl 2‐oxo‐4‐phenylbutyrate (OPBE). By rational design of the active pocket, the substrate specificity of the reductase was significantly altered and this tailor‐made reductase showed a much higher activity toward aromatic α‐keto esters (∼7‐fold increase in kcat/Km toward CBFM) and lower activity toward aliphatic keto esters (∼12‐fold decrease in kcat/Km toward COBE). Meanwhile, the thermostability of the reductase was enhanced by a consensus approach. Such improvements may yield practical catalysts for the asymmetric bioreduction of these aromatic α‐keto estersmagnified image
Scandium‐Catalyzed Cascade Cyclization to Produce Cyclobutane‐Fused Tetrahydroquinoline, Chromane, Thiochromane, and Tetrahydronaphthalene Derivatives
Authors: Nakano Shun‐ichi , Kakugawa Kazumi , Nemoto Tetsuhiro , Hamada Yasumasa 
Published: May 2014

AbstractWe have succeeded in the highly diastereoselective synthesis of cyclobutane‐fused multi‐cyclic compounds using a scandium‐catalyzed cascade cyclization. Using 3–10 mol% of scandium(III) triflate [Sc(OTf)3], various cyclobutane‐fused tetrahydroquinoline derivatives as well as its chromane, thiochromane, and tetrahydronaphthalene analogues were obtained in good to excellent yields. Derivatizations of the reaction products, as well as the plausible reaction mechanism, are also discussed.magnified image
Poly(4‐vinylimidazolium)s/Diazabicyclo[5.4.0]undec‐7‐ene/Zinc(II) Bromide‐Catalyzed Cycloaddition of Carbon Dioxide to Epoxides
Authors: Seo Ue Ryung , Chung Young Keun 
Published: May 2014

AbstractPoly(4‐vinylimidazolium)s, derived from the self‐immobilization of 4‐vinylimidazoliums, with diazabicyclo[5.4.0]undec‐7‐ene (DBU) and zinc bromide (ZnBr2) are used as a highly efficient catalyst for the chemical fixation of carbon dioxide. This catalytic system has been applied for the preparation of cyclic carbonates from terminal epoxides and carbon dioxide. Many functional groups, including chloro, vinyl, ether, and hydroxy groups are well tolerated in the reactions. Moreover, the catalytic system was found to catalyze the conversion of more sterically congested epoxides which are generally considered to be challenging substrates for fabricating the cyclic organic carbonates. In addition, the disubstituted epoxides are found to react with retention of configuration. The polymer precatalyst is easily recovered and reused. A plausible reaction mechanism is proposed.magnified image
Improved and Practical Synthesis of [2,4,5‐Tris(trimethylsilyl)‐ phenyl](phenyl)iodonium Triflate and Utilization as a 1,4‐Benzdiyne Synthon
Authors: Gondo Keisuke , Kitamura Tsugio 
Published: May 2014

AbstractAn efficient and improved method for preparing [2,4,5‐tris(trimethylsilyl)phenyl](phenyl)iodonium triflate as a 1,4‐benzdiyne synthon was developed by using phenyiodonium diacetate/boron triflouride⋅diethyl etherate [PhI(OAc)2/BF3⋅OEt2] reagent. The iodonium triflate generated 3,4‐bis(trimethylsilyl)benzyne quantitatively to give cycloadducts with tetraphenylcyclopentadienone, furan and anthracene in high yields. These cycloadducts bearing two trimethylsilyl groups were transformed into the corresponding aryne precursors, which underwent subsequent cycloaddition reactions to afford polycyclic aromatic compounds such as 1,4‐dihydro‐1,4‐epoxyanthracene, naphthotriazole, triptycene, and anthratriazole derivatives in good to high yields. The total reactions are formally considered as double cycloaddition reactions of 1,4‐benzdiyne. This practical and useful formal benzdiyne strategy is described.magnified image
Variable‐emittance infrared electrochromic skins combining unique conducting polymers, ionic liquid electrolytes, microporous polymer membranes, and semiconductor/polymer coatings, for spacecraft thermal control
Authors: Chandrasekhar Prasanna , Zay Brian J. , Lawrence David , Caldwell Edmonia , Sheth Rubik , Stephan Ryan , Cornwell John 
Published: May 2014

ABSTRACTVariable emittance (ε) is a property vital for the increasing needs in thermal control of future microspacecraft. This article describes fabrication, function, and performance of thin‐film, flexible, variable‐emittance (V‐E) electrochromic skins that use a conducting polymer/‐Au/‐microporous membrane (CP/Au/µP) base, and a new, unique ionic liquid electrolyte (IonEl). Poly(aniline‐co‐diphenyl amine) with a long‐chain polymeric dopant is used as the CP. A unique, patented device design yields no barrier between the active, electrochromic CP surface and the external environment, except for a thin, infrared‐transparent semiconductor/polymer film that lowers solar absorptance [α(s)] and protects from atomic‐O/far‐UV. Use of the IonEl requires special activation methods. Data presented show tailorable ε variations from 0.19 to 0.90, Δε values of >0.50 (which is the highest reported thus far for any functional V‐E material, to our knowledge), α(s) < 0.35, and nearly indefinite cyclability. Extended space durability testing, including calorimetric thermal vacuum and continuous light/dark cycling over >7 months under space conditions (<10−5Pa vacuum, far‐UV), show excellent durability. Other data show resistance to solar wind, atomic‐O, electrostatic discharge, and micrometeoroids. These lightweight, inexpensive, advanced polymeric materials represent the only technology that can work with micro‐ (<20 kg) and nano‐ (<2 kg) spacecraft, thus eventually allowing for much greater flexibility in their design and potentially “democratizing” the entire space industry, for example, allowing small firms to launch their own, dedicated satellites. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci.2014,131, 40850.
Polymer‐based route to ferroelectric lead strontium titanate thin films
Authors: Benkler Manuel , Hobmaier Jost , Gleißner Uwe , Medesi Anna , Hertkorn Daniel , Hanemann Thomas 
Published: May 2014

ABSTRACTCeramic films with high values of ferroelectricity, piezoelectricity, and dielectricity with perovskite structure, like lead zirconate titanate (PZT, PbZrxTi1‐xO3), lead strontium titanate (PST, PbxSr1‐xTiO3), and barium strontium titanate (BST, BaxSr1−xTiO3), are subjects of intensive research due to their use in sensors, energy harvesters, capacitors, and FeRAMs. Here a novel, simple way to produce micropatterned perovskite PST thin films on silicon substrates by a polymer‐based direct UV‐lithography process is presented. By acrylic acid modification of PST precursor sols it is possible to generate photosensitive metal organic PST precursor xerogel films by spin‐coating and subsequently drying on silicon wafers. These films can be patterned by UV‐lithography and developed with organic solvents. The resulting patterned gel films can be crystallized in air via rapid thermal annealing. The obtained perovskite thin ceramic films are polycrystalline and fine grained. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40901.
Preparation of polymer electrolytes based on the polymerized imidazolium ionic liquid and their applications in lithium batteries
Authors: Li Mingtao , Wang Lu , Du Tingting 
Published: May 2014

ABSTRACTThe polymer electrolytes based on a polymerized ionic liquid (PIL) as polymer host and containing 1,2‐dimethyl‐3‐butylimidazolium bis(trifluoromethanesulfonyl)imide (BMMIM‐TFSI) ionic liquid, lithium TFSI salt, and nanosilica are prepared. The PIL electrolyte presents a high ionic conductivity, and it is 1.07 × 10−3 S cm−1 at 60°C, when the BMMIM‐TFSI content reaches 60% (the weight ratio of BMMIM‐TFSI/PIL). Furthermore, the electrolyte exhibits wide electrochemical stability window and good lithium stripping/plating performance. Preliminary battery tests show that Li/LiFePO4 cells with the PIL electrolytes are capable to deliver above 146 mAh g−1 at 60°C with very good capacity retention. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40928.
Variability of weather regimes in the North Atlantic‐European area: past and future
Authors: Hertig Elke , Jacobeit Jucundus 
Published: May 2014

AbstractThe concept of weather regimes represents a process‐oriented method of organizing the varying states of the atmospheric circulation. We define weather regimes as preferred, or recurrent, circulation patterns. We use a suite of reanalysis products and general circulation model (GCM) simulations to assess the reproducibility and variability of the regimes. We find distinct variability of the regimes in observational periods as well as in future projections. Most notable is the high variability of the North Atlantic Oscillation (NAO) regime anomaly patterns in the GCM simulations which is not evident in reanalyses, and the substantial increase of variability regarding the frequency of occurrence of the Atlantic ridge regime and the NAO+ regime.
Understanding and representing atmospheric convection across scales: recommendations from the meeting held at Dartington Hall, Devon, UK, 28–30 January 2013
Authors: Holloway Christopher E. , Petch Jon C. , Beare Robert J. , Bechtold Peter , Craig George C. , Derbyshire Stephen H. , Donner Leo J. , Field Paul R. , Gray Suzanne L. , Marsham John H. , Parker Douglas J. , Plant Robert S. , Roberts Nigel M. , Schultz David M. , Stirling Alison J. , Woolnough Steven J. 
Published: May 2014

AbstractAs weather and climate models move towards higher resolution, there is growing excitement about potential future improvements in the understanding and prediction of atmospheric convection and its interaction with larger‐scale phenomena. A meeting in January 2013 in Dartington, Devon was convened to address the best way to maximise these improvements, specifically in a UK context but with international relevance. Specific recommendations included increased convective‐scale observations, high‐resolution virtual laboratories, and a system of parameterization test beds with a range of complexities. The main recommendation was to facilitate the development of physically based convective parameterizations that are scale‐aware, non‐local, non‐equilibrium, and stochastic.
Development of all‐in‐one multicistronic Tet‐On lentiviral vectors for inducible co‐expression of two transgenes
Authors: Huang Yide , Zhen Ruonan , Jiang Meiqin , Yang Jie , Yang Yun , Huang Zhen , Lin Yao 
Published: May 2014

AbstractInducible co‐expression of multiple genes is often needed in research. Here we describe a single‐vector‐based Tet‐On inducible system for co‐expression of two transgenes. The two transgenes (DsRed1 and eGFP as model genes) and reverse tetracycline‐controlled transactivator were separated by internal ribosomal entry sites and 2A sequences, and their transcription was controlled by the same tetracycline responsive element. Two novel vectors with different internal ribosomal entry sites and 2A positions on the vectors were constructed. The DsRed1 and eGFP in cells transduced with both vectors are undetectable in the absence of doxycycline and can be efficiently induced in the presence of doxycycline in vitro and in vivo. These two vectors can be useful tools when regulated co‐expression of two ecotopic genes is needed.
Self‐reported immature defense style as a predictor of outcome in short‐term and long‐term psychotherapy
Authors: Laaksonen Maarit A. , Sirkiä Carlos , Knekt Paul , Lindfors Olavi 
Published: May 2014

AbstractObjectiveIdentification of pretreatment patient characteristics predictive of psychotherapy outcome could help to guide treatment choices. This study evaluates patients' initial level of immature defense style as a predictor of the outcome of short‐term versus long‐term psychotherapy.MethodIn the Helsinki Psychotherapy Study, 326 adult outpatients with mood or anxiety disorder were randomized to individual short‐term (psychodynamic or solution‐focused) or long‐term (psychodynamic) psychotherapy. Their defense style was assessed at baseline using the 88‐item Defense Style Questionnaire and classified as low or high around the median value of the respective score. Both specific (Beck Depression Inventory [BDI], Hamilton Depression Rating Scale [HDRS], Symptom Check List Anxiety Scale [SCL‐90‐Anx], Hamilton Anxiety Rating Scale [HARS]) and global (Symptom Check List Global Severity Index [SCL‐90‐GSI], Global Assessment of Functioning Scale [GAF]) psychiatric symptoms were measured at baseline and 3–7 times during a 3‐year follow‐up.ResultsPatients with high use of immature defense style experienced greater symptom reduction in long‐term than in short‐term psychotherapy by the end of the 3‐year follow‐up (50% vs. 34%). Patients with low use of immature defense style experienced faster symptom reduction in short‐term than in long‐term psychotherapy during the first year of follow‐up (34% vs. 19%).ConclusionKnowledge of patients' initial level of immature defense style may potentially be utilized in tailoring treatments. Further research on defense styles as outcome predictors in psychotherapies of different types is needed.
Phosphoramidates as Novel Activity‐Based Probes for Serine Proteases
Authors: Haedke Ute R. , Frommel Sandra C. , Hansen Fabian , Hahne Hannes , Kuster Bernhard , Bogyo Matthew , Verhelst Steven H. L. 
Published: May 2014

AbstractActivity‐based probes (ABPs) are small molecules that exclusively form covalent bonds with catalytically active enzymes. In the last decade, they have especially been used in functional proteomics studies of proteases. Here, we present phosphoramidate peptides as a novel type of ABP for serine proteases. These molecules can be made in a straightforward manner by standard Fmoc‐based solid‐phase peptide synthesis, allowing rapid diversification. The resulting ABPs covalently bind different serine proteases, depending on the amino acid recognition element adjacent to the reactive group. A reporter tag enables downstream gel‐based analysis or LC‐MS/MS‐mediated identification of the targeted proteases. Overall, we believe that these readily accessible probes will provide new avenues for the functional study of serine proteases in complex proteomes.
Mechanistic Investigation of the Reaction of Epoxides with Heterocumulenes Catalysed by a Bimetallic Aluminium Salen Complex
Authors: Beattie Christopher , North Michael 
Published: May 2014

AbstractThe bimetallic aluminium(salen) complex [(Al(salen))2O] is known to catalyse the reaction between epoxides and heterocumulenes (carbon dioxide, carbon disulfide and isocyanates) leading to five‐membered ring heterocycles. Despite their apparent similarities, these three reactions have very different mechanistic features, and a kinetic study of oxazolidinone synthesis combined with previous kinetic work on cyclic carbonate and cyclic dithiocarbonate synthesis showed that all three reactions follow different rate equations. An NMR study of [Al(salen)]2O and phenylisocyanate provided evidence for an interaction between them, consistent with the rate equation data. A variable‐temperature kinetics study on all three reactions showed that cyclic carbonate synthesis had a lower enthalpy of activation and a more negative entropy of activation than the other two heterocycle syntheses. The kinetic study was extended to oxazolidinone synthesis catalysed by the monometallic complex Al(salen)Cl, and this reaction was found to have a much less negative entropy of activation than any reaction catalysed by [Al(salen)]2O, a result that can be explained by the partial dissociation of an oligomeric Al(salen)Cl complex. A mechanistic rationale for all of the results is presented in terms of [Al(salen)]2O being able to function as a Lewis acid and/or a Lewis base, depending upon the susceptibility of the heterocumulene to reaction with nucleophiles.
Long‐Range Chemical Ligation from N→N Acyl Migrations in Tryptophan Peptides via Cyclic Transition States of 10‐ to 18‐Members
Authors: Biswas Suvendu , Kayaleh Roger , Pillai Girinath G. , Seon Christopher , Roberts Ian , Popov Vadim , Alamry Khalid A. , Katritzky Alan R. 
Published: May 2014

AbstractChemical ligations to form native peptides from N→N acyl migrations in Trp‐containing peptides via 10‐ to 18‐membered cyclic transition states are described. In this study, a statistical, predictive model that uses an extensive synthetic and computational approach to rationalize the chemical ligation is reported. N→N acyl migrations that form longer native peptides without the use of Cys/Ser/Tyr residues or an auxiliary group at the ligation site were achieved. The feasibility of these traceless chemical ligations is supported by the NC bond distance in N‐acyl isopeptides. The intramolecular nature of the chemical ligations is justified by using competitive experiments and theoretical calculations.
Vibrational Spectra of Chemical and Isotopic Variants of Oxyluciferin, the Light Emitter of Firefly Bioluminescence
Authors: Maltsev Oleg V. , Yue Ling , Rebarz Mateusz , Hintermann Lukas , Sliwa Michel , Ruckebusch Cyril , Pejov Ljupčo , Liu Ya‐Jun , Naumov Panče 
Published: May 2014

AbstractThe chemical complexity of oxyluciferin (OxyLH2), the light‐emitting molecule in the bioluminescence of fireflies, originates from the possibility of keto/enol tautomerism and single or double deprotonation. Herein, we present detailed infrared spectroscopic analysis of OxyLH2 and several of its chemical isomers and isotopomers. To facilitate the future characterization of its biogenic forms, we provide accurate assignments of the solid‐state and solution FTIR spectra of OxyLH2 based on comparison to six isotopically labeled variants ([2‐13C]‐OxyLH2, [3‐15N]‐OxyLH2, [4‐13C]‐OxyLH2, [5‐13C]‐OxyLH2, [2′‐13C]‐OxyLH2, [3′‐15N]‐OxyLH2), five closely related structural analogues, and theoretically computed spectra. The computed DFT harmonic vibrational force fields (B3LYP and M06 functionals with basis sets of varying flexibility up to 6‐311++G**) reproduce well the observed shifts in the IR spectra of both isotopically labeled and structurally related analogues.