bluuebunny/crossref_metadata_2025_split huggingface dataset:
Response of the mantle to flat slab evolution: Insights from local S splitting beneath Peru
Authors: Eakin Caroline M. , Long Maureen D. , Beck Susan L. , Wagner Lara S. , Tavera Hernando , Condori Cristóbal 
Published: April 2014

AbstractThe dynamics of flat subduction, particularly the interaction between a flat slab and the overriding plate, are poorly understood. Here we study the (seismically) anisotropic properties and deformational regime of the mantle directly above the Peruvian flat slab. We analyze shear wave splitting from 370 local S events at 49 stations across southern Peru. We find that the mantle above the flat slab appears to be anisotropic, with modest average delay times (~0.28 s) that are consistent with ~4% anisotropy in a ~30 km thick mantle layer. The most likely mechanism is the lattice‐preferred orientation of olivine, which suggests that the observed splitting pattern preserves information about the mantle deformation. We observe a pronounced change in anisotropy along strike, with predominately trench‐parallel fast directions in the north and more variable orientations in the south, which we attribute to the ongoing migration of the Nazca Ridge through the flat slab system.
Seasonal characteristics of aerosol optical properties at the SKYNET Hefei site (31.90°N, 117.17°E) from 2007 to 2013
Authors: Wang Zhenzhu , Liu Dong , Wang Zhien , Wang Yingjian , Khatri Pradeep , Zhou Jun , Takamura Tamio , Shi Guangyu 
Published: April 2014

AbstractSeasonal characteristics of aerosol optical properties in Sky Radiometer Network (SKYNET) Hefei site are studied using a sky radiometer from March 2007 to May 2013. The aerosol optical depth (AOD), Angstrom exponent (AE), volume size distributions, single‐scattering albedo (SSA), refractive index, and asymmetry factor (ASY) of aerosols are simultaneously retrieved using the SKYRAD.pack version 4.2 software. During the study period, the AOD varied seasonally, with the maximum value of 1.02 ± 0.42 at 500 nm occurring in the summer, and the highest AOD (1.13 ± 0.42) occurred in June due to stagnant climate conditions and accumulation of polluted aerosols before the East Asian summer monsoon. The variation in AE showed a different pattern, with the minimum (0.97 ± 0.28) and maximum values (1.30 ± 0.22) occurring during the spring and fall seasons, respectively. The relatively low value of AE in spring is related to the emission of Asian dust events. The aerosol volume size distributions can be expressed by the trimodal patterns for each season, consisting of a fine mode with R < 0.6 µm, a coarse mode with R > 2.5 µm, and a middle mode located between them. The real part of the refractive index increased with wavelength (380–870 nm) while the imaginary part of the refractive index decreased for all seasons except for the summer. The seasonal mean values of SSA were 0.97 ± 0.02 (summer), 0.95 ± 0.03 (spring), 0.93 ± 0.04 (autumn), and 0.91 ± 0.04 (winter) at 380 nm indicating more absorbing aerosol in the autumn and winter months. Furthermore, aerosol properties were greatly modified by condensation growth as evidenced by the positive dependencies of AOD, SSA, and ASY on relative humidity.
The response of US summer rainfall to quadrupled CO2 climate change in conventional and superparameterized versions of the NCAR community atmosphere model
Authors: Kooperman Gabriel J. , Pritchard Michael S. , Somerville Richard C. J. 
Published: April 2014

AbstractObservations and regional climate modeling (RCM) studies demonstrate that global climate models (GCMs) are unreliable for predicting changes in extreme precipitation. Yet RCM climate change simulations are subject to boundary conditions provided by GCMs and do not interact with large‐scale dynamical feedbacks that may be critical to the overall regional response. Limitations of both global and regional modeling approaches contribute significant uncertainty to future rainfall projections. Progress requires a modeling framework capable of capturing the observed regional‐scale variability of rainfall intensity without sacrificing planetary scales. Here the United States summer rainfall response to quadrupled CO2 climate change is investigated using conventional (CAM) and superparameterized (SPCAM) versions of the NCAR Community Atmosphere Model. The superparameterization approach, in which cloud‐resolving model arrays are embedded in GCM grid columns, improves rainfall statistics and convective variability in global simulations. A set of 5 year time‐slice simulations, with prescribed sea surface temperature and sea ice boundary conditions harvested from preindustrial and abrupt four times CO2 coupled Community Earth System Model (CESM/CAM) simulations, are compared for CAM and SPCAM. The two models produce very different changes in mean precipitation patterns, which develop from differences in large‐scale circulation anomalies associated with the planetary‐scale response to warming. CAM shows a small decrease in overall rainfall intensity, with an increased contribution from the weaker parameterized convection and a decrease from large‐scale precipitation. SPCAM has the opposite response, a significant shift in rainfall occurrence toward higher precipitation rates including more intense propagating Central United States mesoscale convective systems in a four times CO2 climate.
Adaptive robust boundary control of shaft vibrations under perturbations with unknown upper bounds
Authors: Tavasoli Ali 
Published: April 2014

SummaryThis paper presents robust and adaptive boundary control designs to stabilize the two‐dimensional vibration of hybrid shaft model. The hybrid shaft is mathematically represented by a set of partial differential equations, governing the shaft vibrations, coupled to ordinary differential equations, describing rigid body spinning and dynamic boundary conditions. The control objective is to stabilize the transverse vibrations of the perturbed shaft while regulating the spinning rate. To achieve this, the paper first establishes robust boundary control laws that fulfil the control objective in the presence of modeling uncertainties and external disturbances operating over the shaft domain and boundary. Lyapunov‐based analyses show that the proposed robust control exponentially stabilizes the shaft with vanishing distributive perturbations, while assuring ultimately bounded vibrations in the case of nonvanishing perturbations. Then, adaptive control philosophy is utilized to achieve redesigned robust controllers that only use online adaptation of control gains without acquiring the knowledge of bounds on perturbations, as well as dynamic parameters. An advantage of this design is avoiding an overconservative robust control law, which may induce poor stability and chattering in tackling system perturbations with unknown upper bounds. Simulations through finite element method illustrate the results. Copyright © 2014 John Wiley & Sons, Ltd.
Adaptive actuator failure compensation design for unknown chaotic multi‐input systems
Authors: Tahoun A. H. 
Published: April 2014

SummaryIn this paper, an adaptive control approach is designed for compensating the faults in the actuators of chaotic systems and maintaining the acceptable system stability. We propose a state‐feedback model reference adaptive control scheme for unknown chaotic multi‐input systems. Only the dimensions of the chaotic systems are required to be known. Based on Lyapunov stability theory, new adaptive control laws are synthesized to accommodate actuator failures and system nonlinearities. An illustrative example is studied. The simulation results show the effectiveness of the design method. Copyright © 2014 John Wiley & Sons, Ltd.
Diversified Construction of Chromeno[3,4‐c]pyridin‐5‐one and Benzo[c]chromen‐6‐one Derivatives by Domino Reaction of 4‐Alkynyl‐2‐oxo‐2H‐chromene‐3‐carbaldehydes
Authors: Xiao Jian , Chen Yuye , Zhu Shuai , Wang Liang , Xu Lubin , Wei Hongtao 
Published: April 2014

AbstractSilver‐catalyzed three‐component, tandem reactions of 4‐alkynyl‐2‐oxo‐2H‐chromene‐3‐carbaldehydes, amines and various nucleophiles result in the formation of highly functionalized chromeno[3,4‐c]pyridin‐5‐ones in high yields. Gold‐catalyzed [4+2] cycloadditions of 4‐alkynyl‐2‐oxo‐2H‐chromene‐3‐carbaldehydes with alkynes or alkenes have also been achieved to afford benzo[c]chromen‐6‐ones efficiently.magnified image
Cobalt‐Catalyzed ortho‐CH Alkylation of 2‐Arylpyridines via Ring‐Opening of Aziridines
Authors: Gao Ke , Paira Rupankar , Yoshikai Naohiko 
Published: April 2014

AbstractA cobalt–N‐heterocyclic carbene catalyst, in combination with neopentylmagnesium bromide, was found to promote ortho‐CH functionalization of 2‐arylpyridines with 1,2‐diarylaziridines through ring‐opening alkylation. The reaction affords 1,1‐diarylethanes bearing 2‐amino functional groups in moderate to good yields under mild room‐temperature conditions.magnified image
ortho‐Allylation of 1‐Arylpyrazoles with Allyl Phenyl Ether via Iron‐Catalyzed CH Bond Activation under Mild Conditions
Authors: Asako Sobi , Norinder Jakob , Ilies Laurean , Yoshikai Naohiko , Nakamura Eiichi 
Published: April 2014

AbstractAn iron salt and a bipyridine‐type ligand catalyze the ortho‐allylation of 1‐arylpyrazoles and congeners with allyl phenyl ether under mild conditions (0 °C). The ligand, an organozinc base, and the nature of the allylating reagent are crucial for the success of this reaction. Under these conditions, a competitive phenylation reaction is largely retarded, and cross‐coupling of the organozinc with the allyl electrophile is minimized. The reaction may proceed via iron‐catalyzed ortho CH activation to form a metallic intermediate, which then reacts with the allyl ether in a γ selective fashion.magnified image
Palladium‐Catalysed, Directed CH Coupling with Organometallics
Authors: Giri Ramesh , Thapa Surendra , Kafle Arjun 
Published: April 2014

AbstractTransition metal (TM)‐catalysed CH coupling using organometallic reagents is developing into a distinct transformation area for the construction of carbon‐carbon (CC) bonds. Among different TMs (Ru, Rh, Pd, Co, Fe), complexes of palladium(II) are emerging as the most effective and versatile catalysts and have already asserted a proven track‐record for the catalytic activation and coupling of unactivated sp2 and sp3 CH bonds with sp2 and sp3 organometallic reagents. A majority of these TM‐catalysed CH coupling reactions utilise a heteroatom contained in substrates as a directing group. In the last decade, both traditional as well as non‐traditional but synthetically useful functional groups have been extensively exploited as directing groups. Novel directing groups based on mechanistic understanding have also been designed to enhance the reactivity of Pd(II) catalysts towards CH bonds. In addition, the unprecedented application of exogenous ligands to Pd(II)‐catalysed CH coupling is also on the rise, and this approach has already demonstrated an extraordinary level of success not only in breaking unactivated CH bonds enantioselectively, but also in improving reactivity of catalysts towards these CH bonds.magnified image
Rhodium(III)‐Catalyzed, CH Activated Annulation to Form Isocoumarins and α‐Pyrones using the ON Bond as an Internal Oxidant
Authors: Li Xing Guang , Liu Kai , Zou Gang , Liu Pei Nian 
Published: April 2014

AbstractA mild, efficient and regioselective CH activation‐based intermolecular redox‐neutral annulation of O‐benzoylhydroxylamines and internal alkynes has been achieved. The protocol employs an ON bond as the internal oxidant and leads to isocoumarins and α‐pyrones.magnified image
Design of Peptidyl Thiourea Derivatives as Organocatalysts for the Asymmetric Ring Opening of meso‐Stilbene Oxides
Authors: Chimni Swapandeep Singh , Kumar Vikas , Bala Neeraj 
Published: April 2014

AbstractChiral peptidyl thiourea organocatalysts were designed and synthesized for asymmetric ring‐opening of cis‐stilbene oxides with N‐phenylpiperazines. Chiral β‐amino alcohols were obtained with up to 95 % ee after crystallization. The configuration at the N‐terminal residue stereogenic center of peptidyl thiourea organocatalyst was found to affect the stereochemical outcome of the reaction.
Impairment of ceramide synthesis causes a novel progressive myoclonus epilepsy
Authors: Vanni Nicola , Fruscione Floriana , Ferlazzo Edoardo , Striano Pasquale , Robbiano Angela , Traverso Monica , Sander Thomas , Falace Antonio , Gazzerro Elisabetta , Bramanti Placido , Bielawski Jacek , Fassio Anna , Minetti Carlo , Genton Pierre , Zara Federico 
Published: April 2014

ObjectiveAlterations of sphingolipid metabolism are implicated in the pathogenesis of many neurodegenerative disorders.MethodsWe identified a homozygous nonsynonymous mutation in CERS1, the gene encoding ceramide synthase 1, in 4 siblings affected by a progressive disorder with myoclonic epilepsy and dementia. CerS1, a transmembrane protein of the endoplasmic reticulum (ER), catalyzes the biosynthesis of C18‐ceramides.ResultsWe demonstrated that the mutation decreases C18‐ceramide levels. In addition, we showed that downregulation of CerS1 in a neuroblastoma cell line triggers ER stress response and induces proapoptotic pathways.InterpretationThis study demonstrates that impairment of ceramide biosynthesis underlies neurodegeneration in humans. Ann Neurol 2014;76:206–212
Toughening‐modified epoxy‐amine system: Cure kinetics, mechanical behavior, and shape memory performances
Authors: Jing Xianghai , Liu Yuyan , Liu Yuxi , Liu Zhenguo , Tan Huifeng 
Published: April 2014

ABSTRACTShape memory epoxy resins are derived on reacting E51 with triethylenetetramine in presence of the toughening agent polypropylene glycol diglycidyl ether (PPGDGE). The curing behaviors are studied with differential scanning calorimetry. The toughening system shows a decrease in activation energy. Šesták–Berggren model is utilized to establish the kinetic equations. The fitting results prove that the equations can well describe the reactions. Tensile tests and dynamic mechanical analysis are used to analyze mechanical performances and thermodynamics. Shape memory properties are characterized by fold‐deploy tests. The elongation at break increases as the concentration of PPGDGE increases. The toughening materials have lower glass transition temperature (Tg). The fixable ratios of all systems are greater than 99.5%. The shape recovery time decreases with increasing the PPGDGE concentration. The optimal system can fully recover its original shape in about 2 min at Tg + 30°C, and exhibit the maximum fold‐deploy cycles as 13 cycles. © 2014 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2014, 131, 40853.
4,6‐Diaryl/heteroarylpyrimidin‐2(1H)‐ones as a New Class of Xanthine Oxidase Inhibitors
Authors: Shukla Shiwani , Kumar Dinesh , Ojha Ritu , Gupta Manish K. , Nepali Kunal , Bedi Preet M. S. 
Published: April 2014

SummaryA series of 4,6‐diaryl/heteroarylpyrimidones was synthesized employing silica‐supported fluoroboric acid under solvent‐free conditions in a microwave reactor. The catalytic influence of HBF4‐SiO2 was investigated in detail to optimize the reaction conditions. The synthesized compounds were evaluated for in vitro xanthine oxidase (XO) inhibitory activity for the first time. Structure‐activity relationship analyses are also presented. Among the synthesized compounds, VA‐5, ‐9, ‐10, ‐12, ‐22, ‐23, and ‐25 were the active inhibitors with IC50 values ranging from 6.45 to 13.46 µM. Compound VA‐25 with a pyridinyl ring as ring A and a thiophenyl ring as ring B emerged as the most potent XO inhibitor (IC50 = 6.45 µM) in comparison to allopurinol (IC50 = 12.24 µM). Some of the important interactions of VA‐25 with the amino acid residues of the active site of XO were figured out by molecular modeling studies.
A lab‐on‐a‐chip device for analysis of amlodipine in biological fluids using peroxyoxalate chemiluminescence system
Authors: Al Lawati Haider A. J. , Al‐Nadabi Mira M. , Varma Gouri B. , Suliman Fakhr Eldin O. , Al‐Abri Hasnaa 
Published: April 2014

ABSTRACTA highly sensitive, rapid and economical method for the determination of amlodipine (AM) in biological fluids was developed using a peroxyoxalate chemiluminescence (CL) system in a lab‐on‐a‐chip device. Peroxyoxalate‐CL is an indirect type of CL that allows the detection of native fluorophores or compounds derivatized with fluorescent labels. Here, fluorescamine was reacted with AM, and the derivatization product was used in a bis‐(2,4,6‐trichlorophenyl)oxalate‐CL system. Fluorescamine reacts selectively with aliphatic primary amine at neutral or basic pH. As most of the calcium channel blocker and many cardiovascular drugs do not contain primary amine, the developed method is highly selective. The parameters that influenced the CL signal intensity were studied carefully. These included the chip geometry, pH, concentration of reagents used and flow rates. Moreover, we confirmed our previous observation about the effects of imidazole, which is commonly used in the bis‐(2,4,6‐trichlorophenyl)oxalate‐CL system as a catalyst, and found that the signal was significantly improved when imidazole was absent. Under optimized conditions, a calibration curve was obtained with a linear range (10–100 µg/L). The limit of detection was 3 µg/L, while the limit of quantification was 10 µg/L. Finally the method was applied for the determination of AM in biological fluids successfully. Copyright © 2014 John Wiley & Sons, Ltd.
A validated LC‐MS/MS assay for the quantitative determination of curdione in rabbit plasma and its application to a pharmacokinetic study after administration of zedoary turmeric oil and bioavailability of the oil
Authors: Peng Ying , Zhang Mei , Li Weiwei , Liu Bingjie , Wu Haiqing , Jiang Fai , Zhao Lulu , Zhu Huafeng 
Published: April 2014

ABSTRACTA selective and sensitive liquid chromatography tandem mass spectrometry method was developed for the first time for the identification and quantification of curdione in rabbit plasma after vaginal drug administration and intravenous administration of zedoary turmeric oil (ZTO) solution (10 mg/kg). The analysis was performed on a triple‐quadrupole tandem mass spectrometer with multiple reaction monitoring mode via electrospray ionization source in positive ionization mode. After mixing with internal standard diazepam, plasma samples were extracted with ethyl ether–acetic ether (1:1, v/v). Chromatographic separation was carried out on a C18 column with gradient elution using a mixture of water and acetonitrile (both containing 0.1% formic acid) as mobile phases. Linearity ranged over 1.06–106 and 10.6–530 ng/mL (r ≥ 0.995) with the lower limit of quantfication 1.06 ng/mL. The intra‐ and inter‐day precision relative standard deviation values were <12% and the accuracy relative error was from −10.6 to −6.1% at all quality control sample levels. The method was applied to a study of the pharmacokinetics of curdione after vaginal drug administration and intravenous administration of ZTO. Copyright © 2014 John Wiley & Sons, Ltd.
Development and validation of a UHPLC‐qTOF‐MS method for quantification of fuziline in rat plasma and its application in a pharmacokinetic study
Authors: Li Yun‐xia , Gong Xiao‐hong , Li Yan , Zhang Ruo‐qi , Xiong Liang , Xie Xiao‐fang , Peng Cheng 
Published: April 2014

ABSTRACTA specific and sensitive UHPLC‐qTOF‐MS method was developed and validated for quantification of fuziline in rat plasma after oral administration of three dosages. The analyte was separated on an Acquity UPLC BEH C18 column with a total running time of 3 min using a mobile phase of 0.1% formic acid aqueous solution and methanol (80:20, v/v) at a flow‐rate of 0.25 mL/min. The calibration curves for fuziline showed good linearity in the concentrations ranging from 1 to 200 ng/mL with correlation coefficients >0.997. The precision, accuracy, recovery and stability were deemed acceptable. The method was applied to a pharmacokinetics study of fuziline in rats. The mean half‐life was 5.93, 6.13 and 5.12 h for 1, 2 and 4 mg/kg oral administration of fuziline, respectively. The peak concentration and area under the concentration–time curve increased linearly with the doses. The sum of these results indicated that, in the range of the doses examined, the pharmacokinetics of fuziline in rat was based on first‐order kinetics. Copyright © 2014 John Wiley & Sons, Ltd.
Aspiration thrombectomy in patients undergoing primary angioplasty: Totality of data to 2013
Authors: Kumbhani Dharam J. , Bavry Anthony A. , Desai Milind Y. , Bangalore Sripal , Byrne Robert A. , Jneid Hani , Bhatt Deepak L. 
Published: April 2014

ObjectivesWe sought to update our meta‐analysis on clinical outcomes with aspiration thrombectomy prior to primary percutaneous coronary intervention (PPCI) compared with conventional PPCI alone due to the availability of additional trial data.BackgroundThe clinical efficacy of adjunctive aspiration thrombectomy in ST‐elevation myocardial infarction (STEMI) patients undergoing PPCI remains controversial. A recent large‐scale randomized trial showed no benefit in terms of mortality at 30 days.MethodsClinical trials that randomized STEMI patients to aspiration thrombectomy prior to PPCI compared with conventional PPCI alone were included.ResultsA total of 11,321 patients from 20 randomized controlled trials were included. The composite major adverse cardiac event (MACE) endpoint was lower in the aspiration thrombectomy arm compared with conventional PPCI alone (risk ratio [RR] = 0.81, 95% CI 0.70–0.94; P = 0.006). Although all‐cause mortality was similar between the adjunctive aspiration thrombectomy arm and PPCI arms (RR = 0.83, 95% CI 0.67–1.01; P = 0.06), late mortality (6–12 months) was significantly reduced (RR = 0.64; 95% CI 0.44–0.92; P = 0.016). Reinfarction (RR = 0.64, 95% CI 0.44–0.92; P = 0.017) and stent thrombosis (RR = 0.54; 95% CI 0.32–0.91; P = 0.021) were similarly lower. Differences in target vessel revascularization were of borderline significance (RR = 0.83, 95% CI 0.68–1.01; P = 0.06).ConclusionsOur meta‐analysis including all randomized controlled trials on aspiration thrombectomy to date demonstrates a significant reduction in adverse clinical outcomes including stent thrombosis compared with conventional PCI alone. © 2014 Wiley Periodicals, Inc.