bluuebunny/crossref_metadata_2025 huggingface dataset:
Solar wind‐ and EUV‐dependent models for the shapes of the Martian plasma boundaries based on Mars Express measurements
Authors: Ramstad Robin , Barabash Stas , Futaana Yoshifumi , Holmström Mats
Published: June 2017

The long operational life (2003‐present) of Mars Express (MEX) has allowed the spacecraft to make plasma measurements in the Martian environment over a wide range of upstream conditions. We have analyzed ∼7000 MEX orbits, covering three orders of magnitude in solar wind dynamic pressure, with data from the on board Analyzer of Space Plasmas and Energetic Particles (ASPERA‐3) package, mapping the locations where MEX crosses the main plasma boundaries, induced magnetosphere boundary (IMB), ionosphere boundary (IB), and bow shock (BS). A coincidence scheme was employed, where data from the Ion Mass Analyzer (IMA) and the Electron Spectrometer (ELS) had to agree for a positive boundary identification, which resulted in crossings from 1083 orbit segments that were used to create dynamic two‐parameter (solar wind density, nsw, and velocity vsw) dependent global dynamic models for the IMB, IB, and BS. The modeled response is found to be individual to each boundary. The IMB scales mainly dependent on solar wind dynamic pressure and EUV intensity. The BS location closely follows the location of the IMB at the subsolar point, though under extremely low nsw and vsw the BS assumes a more oblique shape. The IB closely follows the IMB on the dayside and changes its nightside morphology with different trends for nsw and vsw. We also investigate the influence of extreme ultraviolet (EUV) radiation on the IMB and BS, finding that increased EUV intensity expands both boundaries.
Characterization of Jupiter's secondary auroral oval and its response to hot plasma injections
Authors: Gray R. L. , Badman S. V. , Woodfield E. E. , Tao C.
Published: June 2017

We present Jovian auroral observations from the 2014 January Hubble Space Telescope (HST) campaign and characterize the auroral second oval feature with particular attention to the response to hot plasma injections. The location of the second oval feature lies between the Ganymede and Europa moon footprint contours between 150 and 240° system III longitude, corresponding to a source in the inner magnetosphere between 9 and 13 RJ. At the examined longitudes, this is in the same region of 11–16 RJ known as the pitch angle distribution boundary, beyond which electrons are thought to be scattered into a field‐aligned configuration and cause auroral precipitation. The feature is enhanced in both brightness and longitudinal spread 1–3 days after large hot plasma injections. The precipitating electrons have a higher‐energy and lower flux than the electrons generating large injection signatures. We suggest that wave‐particle interactions are responsible for the scattering of electrons in this region. We also suggest that the plasma injections can act as a temperature anisotropy and particle source to enhance electron scattering into the aurora and the brightness of the second oval feature. Changes to the magnetic field topology around an injection may also generate shear Alfvén waves and therefore accelerate electrons parallel to the magnetic field resulting in precipitation.
Double‐peaked core field of flux ropes during magnetic reconnection
Authors: Liu Chaoxu , Feng Xueshang , Nakamura Rumi , Guo Jianpeng , Wang Rongsheng
Published: June 2017

A flux rope event observed in the magnetotail exhibits a double‐peaked core field feature. The generation of such double‐peaked feature within the flux rope is explored with Hall‐MHD simulations and theoretical analysis based on multiple X line reconnection. Simulations with a guide field produce flux ropes bounded by two active X lines in the thin current sheet. The guide field, combined with Hall‐generated field, leads to a donut‐shaped core field (having a double‐peaked profile) near the magnetic separatrix. Subsequently, it rotates into the central region of the flux rope, which tends to be the force‐free configuration. The analysis shows that there are three major factors affecting the evolution of the core field, including the guide field, convective, and Hall terms originating from the generalized Ohm's law. The convective term can become stronger near the central region of flux rope, and the Hall term dominates the region next to the separatrix during the early stages of the flux rope evolution. It implies that several different factors contribute to the generation of the double‐peaked core field. The results may help explain a variety of core fields available in magnetotail flux ropes.
A 667 year record of coseismic and interseismic Coulomb stress changes in central Italy reveals the role of fault interaction in controlling irregular earthquake recurrence intervals
Authors: Wedmore L. N. J. , Faure Walker J. P. , Roberts G. P. , Sammonds P. R. , McCaffrey K. J. W. , Cowie P. A.
Published: June 2017

Current studies of fault interaction lack sufficiently long earthquake records and measurements of fault slip rates over multiple seismic cycles to fully investigate the effects of interseismic loading and coseismic stress changes on the surrounding fault network. We model elastic interactions between 97 faults from 30 earthquakes since 1349 A.D. in central Italy to investigate the relative importance of co‐seismic stress changes versus interseismic stress accumulation for earthquake occurrence and fault interaction. This region has an exceptionally long, 667 year record of historical earthquakes and detailed constraints on the locations and slip rates of its active normal faults. Of 21 earthquakes since 1654, 20 events occurred on faults where combined coseismic and interseismic loading stresses were positive even though ~20% of all faults are in “stress shadows” at any one time. Furthermore, the Coulomb stress on the faults that experience earthquakes is statistically different from a random sequence of earthquakes in the region. We show how coseismic Coulomb stress changes can alter earthquake interevent times by ~103 years, and fault length controls the intensity of this effect. Static Coulomb stress changes cause greater interevent perturbations on shorter faults in areas characterized by lower strain (or slip) rates. The exceptional duration and number of earthquakes we model enable us to demonstrate the importance of combining long earthquake records with detailed knowledge of fault geometries, slip rates, and kinematics to understand the impact of stress changes in complex networks of active faults.
Evaluation of deep convective transport in storms from different convective regimes during the DC3 field campaign using WRF‐Chem with lightning data assimilation
Authors: Li Yunyao , Pickering Kenneth E. , Allen Dale J. , Barth Mary C. , Bela Megan M. , Cummings Kristin A. , Carey Lawrence D. , Mecikalski Retha M. , Fierro Alexandre O. , Campos Teresa L. , Weinheimer Andrew J. , Diskin Glenn S. , Biggerstaff Michael I.
Published: June 2017

Deep convective transport of surface moisture and pollution from the planetary boundary layer to the upper troposphere and lower stratosphere affects the radiation budget and climate. This study analyzes the deep convective transport in three different convective regimes from the 2012 Deep Convective Clouds and Chemistry field campaign: 21 May Alabama air mass thunderstorms, 29 May Oklahoma supercell severe storm, and 11 June mesoscale convective system (MCS). Lightning data assimilation within the Weather Research and Forecasting (WRF) model coupled with chemistry (WRF‐Chem) is utilized to improve the simulations of storm location, vertical structure, and chemical fields. Analysis of vertical flux divergence shows that deep convective transport in the 29 May supercell case is the strongest per unit area, while transport of boundary layer insoluble trace gases is relatively weak in the MCS and air mass cases. The weak deep convective transport in the strong MCS is unexpected and is caused by the injection into low levels of midlevel clean air by a strong rear inflow jet. In each system, the magnitude of tracer vertical transport is more closely related to the vertical distribution of mass flux density than the vertical distribution of trace gas mixing ratio. Finally, the net vertical transport is strongest in high composite reflectivity regions and dominated by upward transport.
The impact of air pollutants on rainwater chemistry during “urban‐induced heavy rainfall” in downtown Tokyo, Japan
Authors: Uchiyama Ryunosuke , Okochi Hiroshi , Katsumi Naoya , Ogata Hiroko
Published: June 2017

In order to clarify the impact of air pollution on the formation of sudden and locally distributed heavy rain in urban areas (hereafter UHR = urban‐induced heavy rain), we analyzed inorganic ions in rainwater samples collected on an event basis over 5 years from October 2012 to December 2016 in Shinjuku, Tokyo. Hourly rainfall amounts and wet deposition fluxes of acidic components (the sum of H+, NH4+, NO3−, and nonsea‐salt SO42−) in UHR were 13.1 and 17.8 times larger than those in normal rainfall, respectively, indicating that large amount of air pollutants were scavenged and deposited by UHR with large amounts of rainfall. The level of air pollutants, such as NO2, SO2, and potential ozone, in the ambient air increased just before the formation of UHR and decreased sharply at the end of the UHR event. These results indicate that NO2, which was formed secondarily by oxidants, was further oxidized by HO radicals and formed HNO3 just before the formation of UHR, which was subsequently scavenged by UHR.
Multiscale pore structure and its effect on gas transport in organic‐rich shale
Authors: Wu Tianhao , Li Xiang , Zhao Junliang , Zhang Dongxiao
Published: June 2017

A systematic investigation of multiscale pore structure in organic‐rich shale by means of the combination of various imaging techniques is presented, including the state‐of‐the‐art Helium‐Ion‐Microscope (HIM). The study achieves insight into the major features at each scale and suggests the affordable techniques for specific objectives from the aspects of resolution, dimension, and cost. The pores, which appear to be isolated, are connected by smaller pores resolved by higher‐resolution imaging. This observation provides valuable information, from the microscopic perspective of pore structure, for understanding how gas accumulates and transports from where it is generated. A comprehensive workflow is proposed based on the characteristics acquired from the multiscale pore structure analysis to simulate the gas transport process. The simulations are completed with three levels: the microscopic mechanisms should be taken into consideration at level I; the spatial distribution features of organic matter, inorganic matter, and macropores constitute the major issue at level II; and the microfracture orientation and topological structure are dominant factors at level III. The results of apparent permeability from simulations agree well with the values acquired from experiments. By means of the workflow, the impact of various gas transport mechanisms at different scales can be investigated more individually and precisely than conventional experiments.
MO‐Co@N‐Doped Carbon (M = Zn or Co): Vital Roles of Inactive Zn and Highly Efficient Activity toward Oxygen Reduction/Evolution Reactions for Rechargeable Zn–Air Battery
Authors: Chen Biaohua , He Xiaobo , Yin Fengxiang , Wang Hao , Liu Di‐Jia , Shi Ruixing , Chen Jinnan , Yin Hongwei
Published: June 2017

A highly efficient bifunctional oxygen catalyst is required for practical applications of fuel cells and metal–air batteries, as oxygen reduction reaction (ORR) and oxygen evolution reaction (OER) are their core electrode reactions. Here, the MO‐Co@N‐doped carbon (NC, M = Zn or Co) is developed as a highly active ORR/OER bifunctional catalyst via pyrolysis of a bimetal metal–organic framework containing Zn and Co, i.e., precursor (CoZn). The vital roles of inactive Zn in developing highly active bifunctional oxygen catalysts are unraveled. When the precursors include Zn, the surface contents of pyridinic N for ORR and the surface contents of Co–Nx and Co3+/Co2+ ratios for OER are enhanced, while the high specific surface areas, high porosity, and high electrochemical active surface areas are also achieved. Furthermore, the synergistic effects between Zn‐based and Co‐based species can promote the well growth of multiwalled carbon nanotubes (MWCNTs) at high pyrolysis temperatures (≥700 °C), which is favorable for charge transfer. The optimized CoZn‐NC‐700 shows the highly bifunctional ORR/OER activity and the excellent durability during the ORR/OER processes, even better than 20 wt% Pt/C (for ORR) and IrO2 (for OER). CoZn‐NC‐700 also exhibits the prominent Zn–air battery performance and even outperforms the mixture of 20 wt% Pt/C and IrO2.
White Organic LED with a Luminous Efficacy Exceeding 100 lm W−1 without Light Out‐Coupling Enhancement Techniques
Authors: Wu Sheng‐Fan , Li Si‐Hua , Wang Ya‐Kun , Huang Chen‐Chao , Sun Qi , Liang Jiao‐Jiao , Liao Liang‐Sheng , Fung Man‐Keung
Published: June 2017

Luminous efficacy (LE), which is given by the ratio of luminous flux to power, is commonly used to measure the power consumption of a light source. Unfortunately, the LE of white organic light‐emitting diodes (OLEDs) still lags behind those of inorganic LED for practically used (>100 lm W−1). In this paper, an ultraefficient white OLED is discussed based on a newly designed thermally activated delayed fluorescent exciplex host. The resulting white OLED delivers an unusually high forward‐viewing LE of 105.0 lm W−1 and external quantum efficiency (EQE) ηext of ≈30% (without using any optical out‐coupling techniques). As far as it is known, specifically, these efficiencies are the highest values among the published white OLEDs to date. Two‐color warm white emission is realized with Commission International de I'Eclairage coordinates of (0.40, 0.48) at a brightness of 1000 cd m−2. Furthermore, the well‐matched energy alignment endows the device with an extremely low turn‐on voltage (≈2.5 V). Such high efficiencies and excellent device performance should benefit from the advantages of exciplex material solely used as the host. Therefore, this study anticipates that the findings have great potential to boost the LE of OLEDs, and more importantly, fulfill the power efficacy requirement for lighting applications.
Millivolt Modulation of Plasmonic Metasurface Optical Response via Ionic Conductance
Authors: Thyagarajan Krishnan , Sokhoyan Ruzan , Zornberg Leonardo , Atwater Harry A.
Published: June 2017

A plasmonic metasurface with an electrically tunable optical response that operates at strikingly low modulation voltages is experimentally demonstrated. The fabricated metasurface shows up to 30% relative change in reflectance in the visible spectral range upon application of 5 mV and 78% absolute change in reflectance upon application of 100 mV of bias. The designed metasurface consists of nanostructured silver and indium tin oxide (ITO) electrodes which are separated by 5 nm thick alumina. The millivolt‐scale optical modulation is attributed to a new modulation mechanism, in which transport of silver ions through alumina dielectric leads to bias‐induced nucleation and growth of silver nanoparticles in the ITO counter‐electrode, altering the optical extinction response. This transport mechanism, which occurs at applied electric fields of 1 mV nm−1, provides a new approach to use of ionic transport for electrical control over light–matter interactions.
Light‐Switchable Oxygen Vacancies in Ultrafine Bi5O7Br Nanotubes for Boosting Solar‐Driven Nitrogen Fixation in Pure Water
Authors: Wang Shengyao , Hai Xiao , Ding Xing , Chang Kun , Xiang Yonggang , Meng Xianguang , Yang Zixin , Chen Hao , Ye Jinhua
Published: June 2017

Solar‐driven reduction of dinitrogen (N2) to ammonia (NH3) is severely hampered by the kinetically complex and energetically challenging multielectron reaction. Oxygen vacancies (OVs) with abundant localized electrons on the surface of bismuth oxybromide‐based semiconductors are demonstrated to have the ability to capture and activate N2, providing an alternative pathway to overcome such limitations. However, bismuth oxybromide materials are susceptible to photocorrosion, and the surface OVs are easily oxidized and therefore lose their activities. For realistic photocatalytic N2 fixation, fabricating and enhancing the stability of sustainable OVs on semiconductors is indispensable. This study shows the first synthesis of self‐assembled 5 nm diameter Bi5O7Br nanotubes with strong nanotube structure, suitable absorption edge, and many exposed surface sites, which are favorable for furnishing sufficient visible light‐induced OVs to realize excellent and stable photoreduction of atmospheric N2 into NH3 in pure water. The NH3 generation rate is as high as 1.38 mmol h−1 g−1, accompanied by an apparent quantum efficiency over 2.3% at 420 nm. The results presented herein provide new insights into rational design and engineering for the creation of highly active catalysts with light‐switchable OVs toward efficient, stable, and sustainable visible light N2 fixation in mild conditions.
Polymorphic Architectures of Graphene Quantum Dots
Authors: Kim Sejung , Song Youngjun , Heller Michael J.
Published: June 2017

A systematic strategy for designing structured nanomaterials is demonstrated through self‐assembly of graphene quantum dots. The approach reveals that graphene derivatives at the nanoscale assemble into various architectures of nanocrystals in a binary solution system. The shapes of the nanocrystals continue to evolve in terms of the intimate association of organic molecules with the dispersion medium, obtaining a high index faceted superlattice. This facile synthetic process provides a versatile strategy for designing particles to new structured materials systems, exploiting the crystallization of layered graphitic carbon structures within single crystals.
A Nanoparticle‐Decorated Biomolecule‐Responsive Polymer Enables Robust Signaling Cascade for Biosensing
Authors: Lin Zuan‐Tao , Gu Jianhua , Li Chien‐Hung , Lee T. Randall , Xie Lixin , Chen Shuo , Cao Piao‐Yang , Jiang Shan , Yuan Yulin , Hong Xia , Wang Hongting , Wang Dezhi , Wang Xifan , Jiang Gang‐Biao , Heon Mikala , Wu Tianfu
Published: June 2017

To meet the increasing demands for ultrasensitivity in monitoring trace amounts of low‐abundance early biomarkers or environmental toxins, the development of a robust sensing system is urgently needed. Here, a novel signal cascade strategy is reported via an ultrasensitive polymeric sensing system (UPSS) composed of gold nanoparticle (gNP)‐decorated polymer, which enables gNP aggregation in polymeric network and electrical conductance change upon specific aptamer‐based biomolecular recognition. Ultralow concentrations of thrombin (10−18m) as well as a low molecular weight anatoxin (165 Da, 10−14m) are detected selectively and reproducibly. The biomolecular recognition induced polymeric network shrinkage responses as well as dose‐dependent responses of the UPSS are validated using in situ real‐time atomic‐force microscopy, representing the first instance of real‐time detection of biomolecular binding‐induced polymer shrinkage in soft matter. Furthermore, in situ real‐time confocal laser scanning microscopy imaging reveals the dynamic process of gNP aggregation responses upon biomolecular binding.
Electrically Tunable Integrated Thin‐Film Magnetoelectric Resonators
Authors: El‐Ghazaly Amal , Evans Joseph T. , Sato Noriyuki , Montross Naomi , Ohldag Hendrik , White Robert M. , Wang Shan X.
Published: June 2017

Magnetoelectrics have attracted much attention for their ability to control magnetic behavior electrically and electrical behavior magnetically. This feature provides numerous benefits to electronic systems and can potentially serve as the bridge needed to integrate magnetic devices into mainstream electronics. Here, this natural next step is pursued and thin‐film integrated magnetoelectric devices are produced for radio‐frequency (RF) electronics. The first fully integrated, thin‐film magnetoelectric modulators for tunable RF electronics are presented. These devices provide electric field control of magnetic permeability in order to change the phase velocity and resonance frequency of coplanar waveguides. Over the course of this study, the various thin‐film material phenomena, trade‐offs, and integration considerations for composite magnetoelectrics are analyzed and discussed. The fabricated devices achieve reversible tunability of the resonance frequency, characterized by a remarkable converse magnetoelectric coupling coefficient of up to 24 mG cm V−1 using just thin films. Based on this work, suggestions are given for additional optimizations of future designs that will maximize the thin‐film magnetoelectric interactions.
Protein‐Functionalized Indium‐Tin Oxide Nanoantenna Arrays for Selective Infrared Biosensing
Authors: Chen Kai , Guo Peijun , Dao Thang Duy , Li Shi‐Qiang , Ishii Satoshi , Nagao Tadaaki , Chang Robert P. H.
Published: June 2017

Plasmonic nanoantennas afford significantly enhanced near‐fields that can be exploited for ultrasensitive molecular sensing in plasmon‐enhanced vibrational spectroscopy. While elemental gold is usually used in plasmonic biosensing due to its stability and well‐established surface functionalization, compound plasmonic materials with versatile surface functionalization, low‐cost, and lower optical loss especially in the infrared range are receiving considerable attention. This study demonstrates the application of protein‐functionalized single‐crystalline indium‐tin oxide (ITO) nanorod arrays for biosensing in infrared spectroscopy. The ITO nanorod arrays show angle‐dependent plasmon resonances in the mid‐infrared range, whose position and intensity can be readily tuned by varying the incident angle, thereby providing an easy means for selective enhancement of targeted molecular vibrations. The use of phosphonic‐acid‐derived biotin molecules is examined to chemically functionalize the antennas, and the specific adsorption of streptavidin onto them is subsequently demonstrated. The successful surface functionalization of the ITO nanorods demonstrated here facilitates the detection of functional biomolecules and proteins with high specificity.
Fe‐Doped p‐ZnO Nanostructures/n‐GaN Heterojunction for “Blue‐Free” Orange Light‐Emitting Diodes
Authors: Zhao Wanqiu , Xiong Xing , Han Yibo , Wen Li , Zou Zhengguang , Luo Shijun , Li Haixia , Su Jun , Zhai Tianyou , Gao Yihua
Published: June 2017

In order to obtain the necessary band gap for light‐emitting diodes (LEDs) with zero emission at blue wavelengths (“blue‐free”), quasi‐3D nanostructures of p‐type Fe‐doped zinc oxide (ZnO:Fe) are fabricated on an n‐type GaN substrate. The ZnO:Fe nanostructure comprises an array of vertical nanowires attached at the nodes of a 2D network. Elemental analysis and field‐effect‐transistor (FET) and current–voltage (I–V) measurements indicate the successful iron‐doping of ZnO. After doping, the ZnO exhibits p‐type conductivity, a local‐charge‐reservoir layer, and an abundance of Fe‐related deep levels. The cathodoluminescence (CL), photoluminescence (PL) at various temperatures (down to 4.65 K), and electroluminescence (EL) confirm the creation of Fe‐related donor and acceptor levels. New donor levels may be attributed to the substitution of Fe for some Zn sites (“FeZn”), while new acceptor levels may be due to the bind of FeZn with Zn vacancies, (producing FeZn–VZn pairs). These doping‐induced energy levels are helpful in restricting the intrinsic ZnO UV and blue emission, and a stable blue‐free orange LED device is achieved. It has chromaticity coordinates of ∼(0.483, 0.447) and a color temperature of ∼2574 K under bias voltages of 6–16 V, making it potentially applicable to electronic display systems.
Modular Synthesis of Triazole‐Based Chiral Iodoarenes for Enantioselective Spirocyclizations
Authors: Hempel Christian , Maichle‐Mössmer Caeciliea , Pericàs Miquel A. , Nachtsheim Boris J.
Published: June 2017

A new triazole‐based C1‐symmetrical chiral iodoarene was synthesized in a highly modular route. Based on enzymatic kinetic resolution of an easily accessible propargylic alcohol both enantiomers were accessible in enantiopure form. By Huisgen‐type azide‐alkyne cycloaddtion a series of differently substituted iodoarenes was synthesized in high overall yields. Finally this novel iodoarene was successfully applied in the oxidative Kita cyclization of naphthol derivatives. Good yields and high ee values were obtained in the asymmetric spirocyclization via in situ generation of the hypervalent iodine species using mCPBA as the terminal oxidant.

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Cobalt(III)‐Catalyzed Alkylation of Primary C(sp3)–H Bonds with Diazo Compounds
Authors: Yan Sheng‐Yi , Ling Peng‐Xiang , Shi Bing‐Feng
Published: June 2017

Chelation‐assisted C(sp2)–H metalation/carbenoid insertion has been well investigated. However, the analogous carbene functionalization of C(sp3)–H bonds remains a great challenge. Here we report the first cobalt(III)‐catalyzed alkylation of 8‐methylquinolines with diazo compounds through primary C(sp3)–H cobaltation/carbenoid insertion. The reaction is highly efficient, scalable and tolerates a variety of functional groups. Furthermore, the unique protocol can be applied to the synthesis of azatricyclic antibiotic compounds.

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Regioselective and Enantiospecific Synthesis of Dioxepines by (Cyclopentadienyl)ruthenium‐Catalyzed Condensations of Diazocarbonyls and Oxetanes
Authors: Egger Léo , Guénée Laure , Bürgi Thomas , Lacour Jérôme
Published: June 2017

1,4‐Dioxepines result from the decomposition of α‐diazo‐β‐keto esters in the presence of oxetanes using the catalytic combination of the (cyclopentadienyl)ruthenium complex [CpRu(CH3CN)3][BArF] and 1,10‐phenanthroline. The regioselective [4+3] insertions follow an SN1‐like mechanism and occur yet enantiospecifically (es 74%). The retention of configuration was ascertained by vibrational circular dichroism (VCD) and solid state analyses. Furans, products of [4+1] insertions, are only observed as traces in the above protocol. To promote their formation under CpRu catalysis, it is necessary to use a two‐step process with γ‐halogenated alcohols as substrates.

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Few‐Layer Black Phosphorus Nanosheets as Electrocatalysts for Highly Efficient Oxygen Evolution Reaction
Authors: Ren Xiaohui , Zhou Jie , Qi Xiang , Liu Yundan , Huang Zongyu , Li Zhongjun , Ge Yanqi , Dhanabalan Sathish Chander , Ponraj Joice Sophia , Wang Shuangyin , Zhong Jianxin , Zhang Han
Published: June 2017

Black phosphorus (BP) is a new rediscovered layered material, which has attracted enormous interests in the field of electrocatalysis. Recent investigations reveal that bulk BP is a promising electrocatalyst for oxygen evolution reactions (OER), whereas its bulk crystal structure restricts sufficient active sites for achieving highly efficient OER catalytic performances. Toward this end, few‐layer BP nanosheets prepared by facile liquid exfoliation are applied as electrocatalysts and exhibit preferable electrocatalytic OER activity in association with structural robustness; subsequently, the dependence of current density and applied bias potential on the concentration of OH− has also been uncovered. Most importantly, we are aware that reduction in the thickness of BP nanosheets would generate extra active sites from the ultrathin planar structure and complimenting to the electrocatalytic activities. It is further anticipated that the current work might provide further implementation about the OER performance of BP nanosheets, thereby, offering extendable availabilities for BP‐based electrocatalysts in constructing high‐performance OER devices.
If you brew it, who will come? Market segments in the U.S. beer market
Authors: Malone Trey , Lusk Jayson L.
Published: June 2017

This article uses data collected from a large number of representative United States beer drinkers to identify potential market segments through consumers' taste perceptions of various beer brands. We use several well‐established marketing research methods to show that distinctive segments of the beer market underlie aggregate demand for craft beer. Using exploratory factor analysis, we find that consumers tend to group beers by two underlying factors of taste. We then use cluster analysis to provide a description of how market segments are influenced by brand familiarity. Overall, this article highlights consumer heterogeneity in the modern U.S. beer market and provides an example of how one might use primary data to analyze segmentation in a growing but highly competitive market. [EconLit citations: : C83, M3, Q1]
Day 14 bone marrow examination in the management of acute myeloid leukemia
Authors: Terry Christopher M. , Shallis Rory M. , Estey Elihu , Lim Seah H.
Published: June 2017

The National Comprehensive Cancer Network (NCCN) recommends that a repeat bone marrow evaluation is carried out seven to ten days following completion of induction therapy so that if a patient's day 14 bone marrow shows residual blast cell counts of >10%, the patient would proceed early to a second cycle of induction therapy. Although blast cell counts of <5% on day 14 bone marrow is sensitive in predicting remission on day 28, various studies have found that day 14 bone marrow is highly nonspecific because a large proportion of patients with blast cell counts of >5% on day 14 bone marrow would still attain a complete remission of the disease without any further chemotherapy. Clinical decision based on day 14 bone marrow will result in some of these patients being given a second induction therapy unnecessarily. A second cycle of chemotherapy is associated with not only higher risk for treatment‐related mortality but also increased use of hospital resources such as increased intravenous antimicrobials use, longer hospital stay, and higher demand for blood products. In this article, we examined the utility, discussed the shortfalls, and re‐appraised the values of day 14 bone marrow in the management of patients with AML. On the basis of our review, we suggest that the practice of day 14 bone marrow examination should be re‐evaluated and should probably only be carried out in the setting of clinical trials with clear questions to address its role in predicting outcome of the therapeutic intervention.
Thiotepa‐based conditioning versus total body irradiation as myeloablative conditioning prior to allogeneic stem cell transplantation for acute lymphoblastic leukemia: A matched‐pair analysis from the Acute Leukemia Working Party of the European Society for Blood and Marrow Transplantation
Authors: Eder Sandra , Canaani Jonathan , Beohou Eric , Labopin Myriam , Sanz Jaime , Arcese William , Or Reuven , Finke Juergen , Cortelezzi Agostino , Beelen Dietrich , Passweg Jakob , Socié Gerard , Gurman Gunhan , Aljurf Mahmoud , Stelljes Matthias , Giebel Sebastian , Mohty Mohamad , Nagler Arnon
Published: June 2017

The optimal conditioning regimen to employ before hematopoietic stem cell transplantation in acute lymphoblastic leukemia (ALL) is still undecided, and while cyclophosphamide/total body irradiation (Cy/TBI) is the most commonly used myeloablative regimen, there are concerns regarding long‐term toxicity for patients conditioned with this regimen. Thiotepa‐based conditioning is an emerging radiation‐free regimen with recent publications indicative of comparable clinical outcomes to TBI‐based conditioning. In this analysis of the acute leukemia working party of the EBMT, we performed a retrospective matched‐pair analysis, evaluating the outcome of adult patients with ALL who received thiotepa‐based conditioning (n = 180) with those receiving Cy/TBI conditioning (n = 540). The 2‐year leukemia‐free survival and overall survival (OS) rates of both conditioning regimens were comparable, 33% for thiotepa [95% confidence interval (CI): 26.4‐42.8] versus 39% for Cy/TBI (95% CI: 34.8‐44.5] (P = .33) and 46.5% [95% CI: 38.6‐56.1] versus 48.8% [95% CI: 44.2‐54] (P = .9), respectively. There was no significant difference between the two regimens in the incidence of either acute graft versus host disease (GVHD) or chronic GVHD.

Multivariate analysis demonstrated increased relapse incidence for thiotepa conditioning compared to Cy/TBI (HR = 1.78, 95% CI, 1.07‐2.95; P = .03) which did not affect OS. Our results indicate that thiotepa‐based conditioning may not be inferior to Cy/TBI for adult patients with ALL.
Development and validation of a 3D‐printed model of the ostiomeatal complex and frontal sinus for endoscopic sinus surgery training
Authors: Alrasheed Abdulaziz S. , Nguyen Lily H.P. , Mongeau Luc , Funnell W. Robert J. , Tewfik Marc A.
Published: June 2017

Background

Endoscopic sinus surgery poses unique training challenges due to complex and variable anatomy, and the risk of major complications. We sought to create and provide validity evidence for a novel 3D‐printed simulator of the nose and paranasal sinuses.

Methods

Sinonasal computed tomography (CT) images of a patient were imported into 3D visualization software. Segmentation of bony and soft tissue structures was then performed. The model was printed using simulated bone and soft tissue materials. Rhinologists and otolaryngology residents completed 6 prespecified tasks including maxillary antrostomy and frontal recess dissection on the simulator. Participants evaluated the model using survey ratings based on a 5‐point Likert scale. The average time to complete each task was calculated. Descriptive analysis was used to evaluate ratings, and thematic analysis was done for qualitative questions.

Results

A total of 20 participants (10 rhinologists and 10 otolaryngology residents) tested the model and answered the survey. Overall the participants felt that the simulator would be useful as a training/educational tool (4.6/5), and that it should be integrated as part of the rhinology training curriculum (4.5/5). The following responses were obtained: visual appearance 4.25/5; realism of materials 3.8/5; and surgical experience 3.9/5. The average time to complete each task was lower for the rhinologist group than for the residents.

Conclusion

We describe the development and validation of a novel 3D‐printed model for the training of endoscopic sinus surgery skills. Although participants found the simulator to be a useful training and educational tool, further model development could improve the outcome.
Prevalence of atopic disease in patients with eosinophilic esophagitis
Authors: Benninger Michael S. , Strohl Madeleine , Holy Chantal E. , Hanick Andrea L. , Bryson Paul C.
Published: June 2017

Background

The objective of this work was to evaluate prevalence of eosinophilic esophagitis (EoE) in the United States, and analyze prevalence of atopic disease in patients with EoE. The study design was a retrospective administrative database analysis in U.S.‐based outpatient settings.

Methods

A retrospective claims analysis in the inpatient and outpatient setting (using MarketScan) was conducted to analyze prevalence of atopic disease diagnoses in patients with EoE in 2012, and timing of those diagnoses vs EoE.

Results

From published evidence, prevalence of EoE was estimated at 1 to 5 patients per 10,000 and prevalence of asthma, allergic rhinitis (AR), and atopic dermatitis (AD) concurrent to EoE ranged from 20% to 50%, 50% to 75%, and 2% to 19% cases, respectively. From 2009 and 2013, the estimated prevalence of EoE in MarketScan increased from 2.7 to 5.6 per 10,000 enrollees age 34.5 ± 18.43 years (mean ± standard deviation). Age followed a bimodal distribution with peaks at 12 and 41 years. Women accounted for 35.6% cases. Prevalence of asthma, AR, AD, and food allergies up to 12 months post‐EoE diagnosis reached 44.7%, 27.1%, 25.2%, and 16.9%, respectively, with 63.5% of all patients suffering from at least 1 of these 4 diseases and 3.0% suffering from all 4.

Conclusion

The diagnosis of EoE is associated with the diagnoses of asthma, AR, AD, and food allergies. The high prevalence of these conditions in EoE patients further strengthens the hypothesis of a common pathogenesis.
Environmentally Benign, Rapid, and Selective Extraction of Gold from Ores and Waste Electronic Materials
Authors: Yue Chunlin , Sun Huaming , Liu Wen‐Jing , Guan Binbin , Deng Xudong , Zhang Xu , Yang Peng
Published: June 2017

The extraction of gold from ores and electronic waste is an important topic worldwide, as this precious metal has immense value in a variety of fields. However, serious environmental pollution and high energy consumption due to the use of toxic oxidation reagents and harsh reaction conditions is a well‐known problem in the gold industry. Herein, we report a new chemical method based on the combined use of N‐bromosuccinimide (NBS) and pyridine (Py), which has a greatly decreased environmental impact and reagent cost, as well as mild reaction requirements. This method can directly leach Au0 from gold ore and electronic waste to form AuIII in water. The process is achieved in a yield of approximately 90 % at room temperature and a nearly neutral pH. The minimum dose of NBS/Py is as low as 10 mm, which exhibits low toxicity towards mammalian cells and animals as well as aquatic creatures. The high leaching selectivity of Au over other metals during gold leaching is demonstrated, showing that this method has great potential for practical industrial application towards the sustainable refining of gold from ores and electronic waste.
Asymmetric Yttrium‐Catalyzed C(sp3)−H Addition of 2‐Methyl Azaarenes to Cyclopropenes
Authors: Luo Yong , Teng Huai‐Long , Nishiura Masayoshi , Hou Zhaomin
Published: June 2017

An enantioselective C−H addition to a C=C bond represents the most atom‐efficient route for the construction of chiral carbon–carbon skeletons, a central research topic in organic synthesis. We herein report the enantioselective yttrium‐catalyzed C(sp3)−H bond addition of 2‐methyl azaarenes, such as 2‐methyl pyridines, to various substituted cyclopropenes and norbornenes. This process efficiently afforded a new family of chiral pyridylmethyl‐functionalized cyclopropane and norbornane derivatives in high yields and high enantioselectivities (up to 97 % ee).
Direct and Stereospecific Synthesis of N‐H and N‐Alkyl Aziridines from Unactivated Olefins Using Hydroxylamine‐O‐Sulfonic Acids
Authors: Ma Zhiwei , Zhou Zhe , Kürti László
Published: June 2017

A RhII‐catalyzed direct and stereospecific N‐H‐ and N‐alkyl aziridination of olefins is reported that uses hydroxylamine‐O‐sulfonic acids as inexpensive, readily available, and nitro group‐free aminating reagents. Unactivated olefins, featuring a wide range of functional groups, are converted into the corresponding N‐H or N‐alkyl aziridines in good to excellent yields. This operationally simple, scalable transformation proceeds efficiently at ambient temperature and is tolerant towards oxygen and trace moisture.
The Existence of an Isolated Hydronium Ion in the Interior of Proteins
Authors: Ikeda Takuya , Saito Keisuke , Hasegawa Ryo , Ishikita Hiroshi
Published: June 2017

Neutron diffraction analysis studies reported an isolated hydronium ion (H3O+) in the interior of d‐xylose isomerase (XI) and phycocyanobilin‐ferredoxin oxidoreductase (PcyA). H3O+ forms hydrogen bonds (H‐bonds) with two histidine side‐chains and a backbone carbonyl group in PcyA, whereas H3O+ forms H‐bonds with three acidic residues in XI. Using a quantum mechanical/molecular mechanical (QM/MM) approach, we analyzed stabilization of H3O+ by the protein environment. QM/MM calculations indicated that H3O+ was unstable in the PcyA crystal structure, releasing a proton to an H‐bond partner His88, producing H2O and protonated His88. On the other hand, H3O+ was stable in the XI crystal structure. H‐bond partners of isolated H3O+ would be practically limited to acidic residues such as aspartic and glutamic acids in the protein environment.
Preparation, characterization, and in vitro evaluation of chicken feather fiber–thermoplastic polyurethane composites
Authors: Gokce Ozge , Kasap Murat , Akpinar Gurler , Ozkoc Guralp
Published: June 2017

In this study, we aimed to investigate the potential use of keratin biofiber (KBF)‐reinforced biodegradable thermoplastic polyurethane (TPU) composites as tissue engineering scaffolds. The composites were prepared by a solution casting method. Combined salt leaching and thermally induced phase‐separation methods were used to manufacture porous scaffold structures. The mechanical properties were investigated with tensile tests and dynamic mechanical analysis (DMA). An increase in the fiber content increased the modulus and strength of the composites. The DMA results revealed that the storage modulus of the composites compared to that of the neat TPU was improved by the addition of feathers. Scanning electron microscopy analysis indicated that the dispersion of KBF in the TPU matrix was uniform. According to the water contact angle measurements, the hydrophilicity increased with increasing KBF content up to 80%. The thermal properties of the KBF–TPU films were measured by a differential scanning calorimetry method. The increase in the amount of KBF did not significantly affect the glass‐transition temperature values. We examined the cytotoxicity and biocompatibility by performing cell culturing with the L929 mouse fibroblast cell line. The cell viability was found to be greater than 80% for all of the scaffold compositions. This showed that the KBF–TPU composite scaffolds may serve as a highly potent new material for skin tissue engineering applications. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2017, 134, 45338.
Online disclosure of illicit information: Information behaviors in two drug forums
Authors: Costello Kaitlin L. , Martin John D. , Edwards Brinegar Ashlee
Published: June 2017

Although people disclose illicit activities such as drug use online, we currently know little about what information people choose to disclose and share or whether there are differences in behavior depending on the illicit activity being disclosed. This exploratory mixed‐methods study examines how people discuss and disclose the use of two different drugs—marijuana and opioids—on Reddit. In this study, hermeneutic content analysis is employed to describe the type of comments people make in forums dedicated to discussions about illicit drugs. With inductive analysis, seven categories of comments were identified: disclosure, instruction and advice, culture, community norms, moralizing, legality, and banter. Our subsequent quantitative analysis indicates that although the amounts of disclosure are similar in each subreddit, there are more instances of instruction and advice in discussions about opiates, and more examples of banter in comments about marijuana use. In fact, both subreddits have high rates of banter. We argue that banter fosters disclosure in both subreddits, and that banter and disclosure are linked with information‐seeking behaviors in online forums. This work has implications for future explorations of disclosure online and for public health interventions aimed at disseminating credible information about drug use to at‐risk individuals.
Format technology lifecycle analysis
Authors: Duretec Kresimir , Becker Christoph
Published: June 2017

The lifecycles of format technology have been a defining concern for digital stewardship research and practice. However, little evidence exists to provide robust methods for assessing the state of any given format technology and describing its evolution over time. This article introduces relevant models from diffusion theory and market research and presents a replicable analysis method to compute models of technology evolution. Data cleansing and the combination of multiple data sources enable the application of nonlinear regression to estimate the parameters of the Bass diffusion model on format technology market lifecycles. Through its application to a longitudinal data set from the UK Web Archive, we demonstrate that the method produces reliable results and show that the Bass model can be used to describe format lifecycles. By analyzing adoption patterns across market segments, new insights are inferred about how the diffusion of formats and products such as applications occurs over time. The analysis provides a stepping stone to a more robust and evidence‐based approach to model technology evolution.
Observer‐Based Piecewise Fault‐Tolerant Control for Discrete‐Time Nonlinear Dynamic Systems
Authors: Chen Liheng , Huang Xianlin , Liu Ming
Published: June 2017

This paper is concerned with the fault‐tolerant control (FTC) problem against simultaneous actuator and sensor fault for discrete‐time nonlinear systems. The nonlinear plant is represented by Takagi–Sugeno (T–S) fuzzy dynamic models with disturbance and measurement noise. In this work, the original plant is augmented into a descriptor system, where the state and fault are assembled into a new state vector. Based on piecewise quadratic Lyapunov functions, a new T‐S fuzzy fault‐tolerant observer is designed such that both the actuator and sensor faults can be estimated asymptotically. Then, a piecewise observer‐based FTC approach is developed to stabilize the resulting closed‐loop fault system. Finally, a practical example of the truck‐trailer model is presented to illustrate the effectiveness of the proposed method.
A Consensus Protocol over Noisy Two‐Layered Networks with Cooperative and Antagonistic Interactions
Authors: Nguyen L. T. H. , Wada T. , Masubuchi I. , Asai T. , Fujisaki Y.
Published: June 2017

This study is concerned with the consensus problems of multi‐agent systems with cooperative and antagonistic noisy interactions described by two‐layered network. That is, each agent is simultaneously influenced by the force of attraction and repulsion between each neighboring agents in cooperative and antagonistic layers. A distributed algorithm for achieving the consensus in a probabilistic sense is proposed and its sufficient conditions are clarified. The conditions tell us rigorous stopping rules which enable us to know the number of iterations that achieves consensus within a prespecified accuracy and probability. Some applications of consensus problems with cooperative and antagonistic interactions are shown through numerical examples.
Global Practical Tracking for Nonlinear Systems With More Unknowns via Adaptive Output‐Feedback
Authors: Jin Shaoli , Liu Yungang , Li Fengzhong
Published: June 2017

This paper investigates the global practical tracking via adaptive output‐feedback for a class of uncertain nonlinear systems. Essentially different from the closely related literature, the system under investigation possesses unknown time‐varying control coefficients and a polynomial‐of‐output growth rate, and meanwhile, the system nonlinearities and the reference signal allow serious unknowns. For this, an adaptive observer is designed to reconstruct the system unmeasured states, where a new dynamic gain is introduced to compensate the serious unknowns in the system nonlinearities and the reference signal. Based on this and by backstepping technique, an adaptive output‐feedback controller is successfully designed, such that all the states of the closed‐loop system are bounded, and the tracking error will be prescribed sufficiently small after a finite time. A numerical simulation is provided to demonstrate the effectiveness of the proposed method.
Bedienungssteg zum Entnahmeturm der Talsperre Schönbrunn
Authors: Vockrodt Hans‐Jörg
Published: June 2017

Die Errichtung des Bedienungsstegs zum Entnahmeturm der Talsperre Schönbrunn im Jahre 1974 ist hinsichtlich Planung und Bauausführung sowie der darin realisierten Innovationen ein Stück Technikgeschichte. Dieser Beitrag dient rückblickend ihrer Bewahrung und beschreibt aktuelle Instandsetzungsmaßnahmen zum Erhalt des Bauwerks unter besonderen bautechnologischen Bedingungen.