bluuebunny/crossref_metadata_2025_split huggingface dataset:
The variability of nonmigrating tides detected from TIMED/SABER observations
Authors: Li Xing , Wan Weixing , Ren Zhipeng , Liu Libo , Ning Baiqi 
Published: November 2015

AbstractThis paper deals with the variability of the nonmigrating tides detected from the observation of the SABER instrument on board the TIMED satellite during the 11 year solar period from 2002 to 2012. The longitudinal wave number spectra with 1 day resolution were first estimated from the temperature data measured at the MLT altitudes (70–110 km) and at the lower midlatitudes and low latitudes (between ±45°). Then we used the wave number 4 component to obtain the nonmigrating tides in which the dominant component DE3 was further analyzed in detail. We found that the properties of the spatial distribution and large time scale variation of the DE3 component are similar to those of the previous works, which used the interpolated data with 2 month resolution. These properties are that the DE3 component occurs mainly at the low latitudes within ±30° and at the altitudes from 90 to 110 km; the tidal amplitude is larger during boreal summer and early autumn, smaller in spring and almost tends to disappear in winter; the component is slightly stronger during the eastward wind QBO phase than the westward phase. Practically, the higher‐resolution data were used to reveal the day‐to‐day variability of the DE3 component. It is found that (1) the variability occurs mainly at the altitudes from 100 to 110 km with a peak at 106 km; (2) it is strong at the low latitudes and peaks around the equator, as well, slightly stronger in the Southern Hemisphere than in northern one; (3) it is considerably larger around solstitial months than equinoctial months; and (4) it would not experience an obvious interannual variation. The day‐to‐day variability of the DE3 component may be explained by the variance of the absolute amplitudes and the contribution of the wave phases, and the later seems to play more important role.
Counterstreaming electrons in small interplanetary magnetic flux ropes
Authors: Feng H. Q. , Zhao G. Q. , Wang J. M. 
Published: November 2015

AbstractSmall interplanetary magnetic flux ropes (SIMFRs) are commonly observed by spacecraft at 1 AU, and their origin still remains disputed. We investigated the counterstreaming suprathermal electron (CSE) signatures of 106 SIMFRs measured by Wind during 1995–2005. We found that 79 (75%) of the 106 flux ropes contain CSEs, and the percentages of counterstreaming vary from 8% to 98%, with a mean value of 51%. CSEs are often observed in magnetic clouds (MCs), and this indicates these MCs are still attached to the Sun at both ends. CSEs are also related to heliospheric current sheets (HCSs) and the Earth's bow shock. We divided the SIMFRs into two categories: The first category is far from HCSs, and the second category is in the vicinity of HCSs. The first category has 57 SIMFRs, and only 7 of 57 ropes have no CSEs. This ratio is similar to that of MCs. The second category has 49 SIMFRs; however, 20 of the 49 events have no CSEs. This ratio is larger than that of MCs. These two categories have different origins. One category originates from the solar corona, and most ropes are still connected to the Sun at both ends. The other category is formed near HCSs in the interplanetary space.
Site‐Specific N‐Terminal Labeling of Peptides and Proteins using Butelase 1 and Thiodepsipeptide
Authors: Nguyen Giang K. T. , Cao Yuan , Wang Wei , Liu Chuan Fa , Tam James P. 
Published: November 2015

AbstractAn efficient ligase with exquisite site‐specificity is highly desirable for protein modification. Recently, we discovered the fastest known ligase called butelase 1 from Clitoria ternatea for intramolecular cyclization. For intermolecular ligation, butelase 1 requires an excess amount of a substrate to suppress the reverse reaction, a feature similar to other ligases. Herein, we describe the use of thiodepsipeptide substrates with a thiol as a leaving group and an unacceptable nucleophile to render the butelase‐mediated ligation reactions irreversible and in high yields. Butelase 1 also accepted depsipeptides as substrates, but unlike a thiodesipeptide, the desipeptide ligation was partially reversible as butelase 1 can tolerate an alcohol group as a poor nucleophile. The thiodesipeptide method was successfully applied in N‐terminal labeling of ubiquitin and green fluorescent protein using substrates with or without a biotin group in high yields.
Ultrafast Electron Transfer Kinetics of Graphene Grown by Chemical Vapor Deposition
Authors: Chen Ran , Nioradze Nikoloz , Santhosh Padmanabhan , Li Zhiting , Surwade Sumedh P. , Shenoy Ganesh J. , Parobek David G. , Kim Min A. , Liu Haitao , Amemiya Shigeru 
Published: November 2015

AbstractHigh electrochemical reactivity is required for various energy and sensing applications of graphene grown by chemical vapor deposition (CVD). Herein, we report that heterogeneous electron transfer can be remarkably fast at CVD‐grown graphene electrodes that are fabricated without using the conventional poly(methyl methacrylate) (PMMA) for graphene transfer from a growth substrate. We use nanogap voltammetry based on scanning electrochemical microscopy to obtain very high standard rate constants k0≥25 cm s−1 for ferrocenemethanol oxidation at polystyrene‐supported graphene. The rate constants are at least 2–3 orders of magnitude higher than those at PMMA‐transferred graphene, which demonstrates an anomalously weak dependence of electron‐transfer rates on the potential. Slow kinetics at PMMA‐transferred graphene is attributed to the presence of residual PMMA. This unprecedentedly high reactivity of PMMA‐free CVD‐grown graphene electrodes is fundamentally and practically important.
Diastereoselektive Synthese von Glykosylphosphaten mit einem Phosphorylase‐Phosphatase‐Kombikatalysator
Authors: Wildberger Patricia , Pfeiffer Martin , Brecker Lothar , Nidetzky Bernd 
Published: November 2015

AbstractZuckerphosphate sind biologisch bedeutsam im Zellmetabolismus, bei der Signalübertragung und als Bausteine in Makromolekülen. Die selektive chemische Phosphorylierung von Zuckern ist schwierig, vor allem am anomeren Zentrum. Eine durch Phosphatase katalysierte diastereoselektive Phosphorylierung am anomeren Zentrum unterschiedlicher Aldosen wird beschrieben. Als Phosphoryldonor der Reaktion fungiert α‐D‐Glukosylphosphat, welches über eine Phosphorylase‐katalysierte Reaktion aus Saccharose und Phosphat hergestellt wird. Simultan und sequenziell durchgeführte Biotransformationen mithilfe des hier entwickelten Phosphorylase‐Phosphatase‐Kombikatalysators ermöglichten die Herstellung verschiedener Glykosylphosphate mit definierter anomerer Konfiguration in Ausbeuten von bis zu 70 % basierend auf der anfänglich eingesetzten Phosphatkonzentration. Für die Isolation der Reaktionsprodukte wurde eine effiziente, enzymunterstützte Aufreinigungsstrategie entwickelt.
Resonance Energy Transfer Relates the Gas‐Phase Structure and Pharmacological Activity of Opioid Peptides
Authors: Kopysov Vladimir , Boyarkin Oleg V. 
Published: November 2015

AbstractEnkephalins are efficient pain‐relief drugs that bind to transmembrane opioid receptors. One key structural parameter that governs the pharmacological activity of these opioid peptides and is typically determined from condensed‐phase structures is the distance between the aromatic rings of their Tyr and Phe residues. We use resonance energy transfer, detected by a combination of cold ion spectroscopy and mass spectrometry, to estimate the Tyr–Phe spacing for enkephalins in the gas phase. In contrast to the condensed‐phase structures, these distances appear to differ substantially in enkephalins with different pharmacological efficiencies, suggesting that gas‐phase structures might be a better pharmacophoric metric for ligand peptides.
Insertion Homo‐ and Copolymerization of Diallyl Ether
Authors: Jian Zhongbao , Mecking Stefan 
Published: November 2015

AbstractThe previously unresolved issue of polymerization of allyl monomers CH2CHCH2X is overcome by a palladium‐catalyzed insertion polymerization of diallyl ether as a monomer. An enhanced 2,1‐insertion of diallyl ether as compared to mono‐allyl ether retards the formation of an unreactive five‐membered cyclic O‐chelate (after 1,2‐insertion) that otherwise hinders further polymerization, and also enhances incorporation in ethylene polymers (20.4 mol %). Cyclic ether repeat units are formed selectively (96 %–99 %) by an intramolecular insertion of the second allyl moiety of the monomer. These features even enable a homopolymerization to yield polymers (poly‐diallyl ether) with degrees of polymerization of DPn≈44.
The Synthesis of Structurally Diverse Macrocycles By Successive Ring Expansion
Authors: Kitsiou Christiana , Hindes Jordan J. , I'Anson Phillip , Jackson Paula , Wilson Thomas C. , Daly Eleanor K. , Felstead Hannah R. , Hearnshaw Peter , Unsworth William P. 
Published: November 2015

AbstractStructurally diverse macrocycles and medium‐sized rings (9–24 membered scaffolds, 22 examples) can be generated through a telescoped acylation/ring‐expansion sequence, leading to the insertion of linear fragments into cyclic β‐ketoesters without performing a discrete macrocyclization step. The key β‐ketoester motif is regenerated in the ring‐expanded product, meaning that the same sequence of steps can then be repeated (in theory indefinitely) with other linear fragments, allowing macrocycles with precise substitution patterns to be “grown” from smaller rings using the successive ring‐expansion (SuRE) method.
Selective Inhibition of the Immunoproteasome by Structure‐Based Targeting of a Non‐catalytic Cysteine
Authors: Dubiella Christian , Baur Regina , Cui Haissi , Huber Eva M. , Groll Michael 
Published: November 2015

AbstractClinically applied proteasome inhibitors induce cell death by concomitant blockage of constitutive and immunoproteasomes. In contrast, selective immunoproteasome inhibition is less cytotoxic and has the potential to modulate chronic inflammation and autoimmune diseases. In this study, we rationally designed decarboxylated peptides that covalently target a non‐catalytic cysteine of the immunoproteasome subunit β5i with α‐chloroacetamide‐containing sidechains. The enhanced isoform specificity decreased cytotoxic effects and the compound suppressed the production of inflammatory cytokines. Structure‐based optimization led to over 150‐fold selectivity for subunit β5i over β5c. This new compound class provides a promising starting point for the development of selective immunoproteasome inhibitors as potential anti‐inflammatory agents.
Diastereoselective Synthesis of Glycosyl Phosphates by Using a Phosphorylase–Phosphatase Combination Catalyst
Authors: Wildberger Patricia , Pfeiffer Martin , Brecker Lothar , Nidetzky Bernd 
Published: November 2015

AbstractSugar phosphates play an important role in metabolism and signaling, but also as constituents of macromolecular structures. Selective phosphorylation of sugars is chemically difficult, particularly at the anomeric center. We report phosphatase‐catalyzed diastereoselective “anomeric” phosphorylation of various aldose substrates with α‐D‐glucose 1‐phosphate, derived from phosphorylase‐catalyzed conversion of sucrose and inorganic phosphate, as the phosphoryl donor. Simultaneous and sequential two‐step transformations by the phosphorylase–phosphatase combination catalyst yielded glycosyl phosphates of defined anomeric configuration in yields of up to 70 % based on the phosphate applied to the reaction. An efficient enzyme‐assisted purification of the glycosyl phosphate products from reaction mixtures was established.
Synthesis of 1,1‐Diborylalkenes through a Brønsted Base Catalyzed Reaction between Terminal Alkynes and Bis(pinacolato)diboron
Authors: Morinaga Akira , Nagao Kazunori , Ohmiya Hirohisa , Sawamura Masaya 
Published: November 2015

AbstractA method for the synthesis of 1,1‐diborylalkenes through a Brønsted base catalyzed reaction between terminal alkynes and bis(pinacolato)diboron has been developed. The procedure allows direct synthesis of functionalized 1,1‐diborylalkenes from various terminal alkynes including propiolates, propiolamides, and 2‐ethynylazoles.
Emission of gravitational waves by precession of slim accretion disks dynamically driven by the Bardeen‐Petterson effect
Authors: Alfonso W.D. , Sánchez L.A. , Mosquera H.J. 
Published: November 2015

AbstractThe electromagnetic radiation emitted from some astro‐physical objects such as active galactic nuclei (AGN), microquasars (M‐QSRs), and central engines of gamma‐ray burst (GRBs), seems to have a similar physical origin: a powerful jet of plasma ejected from a localized system, presumably composed of an accretion disk encircling a compact object. This radiation is generally beamed in the polar directions and in some cases, it appears to have a spiral‐like structure that could be explained if the central system itself precesses. In this work, we use the slim disk accretion model, presented by Popham et al. (1999), to studying the gravitational waves (GWs) emitted by the precession of the accretion disk around a solar‐mass Kerr black hole (KBH). For practical purposes, this model describes the central engine of a class of GRBs when some astro‐physical constrains are fulfilled. The induced precession considered here is driven by the Bardeen‐Petterson effect, which results from the combination of viscous effects in such disks and the relativistic frame‐dragging effect. We evaluate the feasibility of direct detection of the GWs computed for such a model and show that the precession of this kind of systems could be detected by gravitational wave observatories like DECIGO, ultimate‐DECIGO, and BBO, with higher probability if such a class of sources are placed at distances less than 1 Mpc. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
LHCb results in proton‐nucleus collisions at the LHC
Authors: Müller K. 
Published: November 2015

AbstractThe forward acceptance of the LHCb detector allows it to probe proton‐ion collisions in a unique kinematic range, complementary to the other LHC experiments. The production of J/Ψ and Υ‐mesons decaying into two muons is studied at the LHCb experiment in proton‐lead collisions at a proton‐nucleon centre‐of‐mass energy √sNN = 5 TeV. The analysis is based on a data sample corresponding to an integrated luminosity of 1.6 nb–1. The nuclear modification factor and the forward‐backward production ratio are determined for J/Ψ and Υ(1S) mesons. Clear suppression of prompt J/Ψ production is observed with respect to the production in proton‐proton collisions at large rapidity, while the suppression of J/Ψ from b‐hadron decays is less pronounced. The nuclear modification factor for Υ(1S) mesons in the forward region is found to be similar to those for J/Ψ from b‐hadron decays. Furthermore, a first observation of Z bosons at large rapidities in proton‐lead collisions is reported. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Ultraluminous X‐ray pulsar: Accreting magnetar?
Authors: Tong H. 
Published: November 2015

AbstractMagnetars are a special kind of neutron stars. There may also be accreting magnetars. From the studies of isolated magnetars, it is known that a neutron star with a strong dipole field only is not a magnetar. Super‐slow X‐ray pulsars may just be accreting high magnetic‐field neutron stars. The ultra‐luminous X‐ray pulsar NuSTAR J095551+6940.8 may be an accreting magnetar. It may be an accreting low magnetic field magnetar with multipole field of 1014 G and dipole field of 1012 G. This point of view is consistent with the study of isolated magnetars. An ultra‐luminous X‐ray pulsar phase during binary evolution may result in massive millisecond pulsars. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
On the instabiity of the SM for magnetic fields larger than M2W/e
Authors: Cabo Montes de Oca A. , Manreza Paret D. , Pérez Martínez A. , Rodriguez Querts E. , Piccineli G. 
Published: November 2015

AbstractIt is known that the Standard Model (SM) shows an instability threshold at the critical magnetic field value B = M2W/e. This effect is determined by the non‐Abelian origin of the W particles. The nature of the instability is revisited here. It is underlined that the pure magnetic field within the SM is unstable already at the classical level and shows exponentially growing with time solutions. It is noted that the homogeneity of the system implies that there are also crystalline field configurations with similar rapidly increasing with time behavior. The crystalline distributions of W fields show vortical electric currents similar to the ones exhibited by the Abrikosov's vortices in second kind superconductors. With the use of the spatial dependence of these solutions, static variational configurations of the fields are defined here for minimizing the energy of the system. The constructed static field distributions show appreciably lower energies than the classical magnetic field, and have the energy minimum at a finite lattice size. Therefore, the results give further support to former proposals in the literature about the existence of periodic vortex‐like vacuum in the SM at magnetic fields larger than M2 W/e. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Magnetic field effects on the mass‐radius relation of white dwarfs
Authors: Alvear Terrero D. , Castillo García M. , Manreza Paret D. , Horvath J. E. , Pérez Martínez A. 
Published: November 2015

AbstractWe study the anisotropic equation of state (EoS) in both strong and weak magnetic field approximations, taking into account the statistical, vacuum, and Maxwell contributions. In the strong field regime, we perform a polytropic parametrization to the anisotropic EoS, showing that the polytropic index Γ remains close to 4/3 and never reaches the value Γ = 2. We solve the Tolman‐Oppenheimer‐Volkoff (TOV) equations with anisotropic pressures, discarding the super‐Chandrasekhar masses for magnetized white dwarfs (WD). Also, we find the solutions of the anisotropic structure equations (considering cylindrical metric), which allows us to confirm the same bound of B ∼ 1013 G from scalar virial theorem, since beyond this value there are no physical solutions. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Compact stars on the brane: What could they reveal about extra dimensions?
Authors: Lugones G. , Arbañil J. D. V. 
Published: November 2015

AbstractIn this work we investigate the properties of compact stars in the Randall‐Sundrum type II brane‐world model. We analyze the properties of quark and hadronic stars using the MIT bag model and a relativistic mean‐field model for the equation of state. We show that the causality limit in brane‐world models coincides with the Schwarzschild limit. Hence, there is a region in the mass‐radius plane that is forbidden in General Relativity for causal equations of state but can be accessed within brane‐world models. We also show that stable compact stars of arbitrarily large mass are possible because they can be supported against collapse by the non‐local bulk effects on the brane. This features provide a potential test for the existence of extra dimensions through the observation of neutron star's masses and radii. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Strongly self‐magnetized quantum relativistic electron gas expanding as a jet
Authors: Pérez Rojas H. , Rodríguez Querts E. , Pérez Martínez A. 
Published: November 2015

AbstractWe discuss the behavior of a strongly magnetized electron gas whose dominant pressure is exerted along the applied field, and extends along it as a one dimensional system. We suggest a model for maintaining the magnetic field selfconsistently, and for it we conjecture a partial bosonization of the electron gas, described by a charged vector boson field which experiences condensation, leading to a ferromagnetic behavior. Our aim is to suggest a possible quantum relativistic self‐magnetized jet model. High frequency photons will be deviated also along paths parallel to the external field. Any addition of energy to the electron system, would contribute mainly to increase the kinetic energy along the magnetic field axis, an the jet may grow in this way for long times. (© 2015 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)
Quadri‐lineage disease involving nodal B‐cell marginal zone lymphoma, high‐grade B‐cell lymphoma, Kaposi's syndrome, and acute myeloid leukemia
Authors: Laribi Kamel , Ghnaya Habib , Mention Pierre‐Jean , Rousset Hoel , Baugier de Materre Alix , Pineau‐Vincent Fabienne , Truong Catherine , Bolle Delphine 
Published: November 2015

Key Clinical MessageA patient with a marginal zone lymphoma received RCHOP and obtained PR. He received RDHAP, autograft, and obtained CR. Three months later, he developed Kaposi's sarcoma with spontaneous regression. Two months later, he developed DLBCL treated with R‐MIV with CR. Thereafter, he developed AML and died a few days later.
Highly Active Palladium‐Based Catalyst System for the Aerobic Oxidative Direct Coupling of Benzene to Biphenyl
Authors: Liu Yangqing , Wang Xiaochen , Cai Xiaochun , Chen Guojian , Li Jing , Zhou Yu , Wang Jun 
Published: November 2015

AbstractA highly efficient Pd‐containing catalytic system for the intermolecular direct C−H homocoupling of benzene to biphenyl has been developed. The catalytic system was composed of Pd(OAc)2 with trifluoromethanesulfonic acid (TfOH) as an additive and O2 as the sole oxygen source in the absence of any metal‐containing cocatalyst. An excellent efficiency of PdII with the acidic additive was attained in the aerobic oxidation of benzene to biphenyl. A high yield (25.3 %) and selectivity (98 %) were achieved by using a small amount of Pd(OAc)2 (0.07 mol %) and TfOH, which gave a high turnover number (180) for Pd species. Theoretical calculation by DFT and UV/Vis absorption spectra illustrated that the formation of electropositive PdII species in the presence of TfOH contributed to the high efficiency of the catalytic system.
GaN and GaxIn1−xN Nanoparticles with Tunable Indium Content: Synthesis and Characterization
Authors: Lei WeiWei , Willinger Marc Georg , Antonietti Markus , Giordano Cristina 
Published: November 2015

AbstractSemiconducting GaN and GaxIn1−xN nanoparticles (4–10 nm in diameter, depending on the metal ratio) with tunable indium content are prepared through a chemical synthesis (the urea‐glass route). The bandgap of the ternary system depends on its composition, and therefore, the color of the final material can be turned from bright yellow (the color of pure GaN) to blue (the color of pure InN). Transmission electron microscopy (TEM and HRTEM) and scanning electron microscopy (SEM) images confirm the nanoparticle character and homogeneity of the as‐prepared samples. X‐ray diffraction (XRD), electron diffraction (EDX), elemental mapping, and UV/Vis, IR, and Raman spectroscopy investigations are used to confirm the incorporation of indium into the crystal structure of GaN. These nanoparticles, possessing adjusted optical properties, are expected to have potential applications in the fabrication of novel optoelectronic devices.