bluuebunny/crossref_metadata_2025 huggingface dataset:
Tuning excited-state-intramolecular-proton-transfer (ESIPT) process and emission by cocrystal formation: a combined experimental and theoretical study
Authors: Lin Heyang , Chang Xueping , Yan Dongpeng , Fang Wei-Hai , Cui Ganglong
Published: November 2016

The formation of two-component molecular cocrystals can lead to the tunable excited state intramolecular proton transfer (ESIPT) process and emission, as first confirmed by both experimental and computational studies.
Solution self-assembly of plasmonic Janus nanoparticles
Authors: Castro Nicolò , Constantin Doru , Davidson Patrick , Abécassis Benjamin
Published: November 2016

Janus nanoparticles bearing two different properties on a single particle are amenable to self-assembly into higher-order structures via their directional interaction.
Benzothiazole- and benzoxazole-linked porous polymers for carbon dioxide storage and separation
Authors: Rabbani Mohammad Gulam , Islamoglu Timur , El-Kaderi Hani M.
Published: November 2016

The synthesis of highly porous benzoxazole- and benzothiazole-linked organic polymers by condensation routes is reported; the new polymers exhibit high selectivity towards CO2 capture from gas mixtures.
The effect of Mg-doping and Cu nonstoichiometry on the photoelectrochemical response of CuFeO2
Authors: Wuttig Anna , Krizan Jason W. , Gu Jing , Frick Jessica J. , Cava Robert J. , Bocarsly Andrew B.
Published: November 2016

We report the tuning of CuFeO2 photoelectrodes by Mg doping and Cu deficiency to demonstrate the effects of carrier concentration on the photoresponse.
A three-dimensional graphitic carbon nitride belt network for enhanced visible light photocatalytic hydrogen evolution
Authors: Zeng Yunxiong , Liu Chengbin , Wang Longlu , Zhang Shuqu , Ding Yangbin , Xu Yuzi , Liu Yutang , Luo Shenglian
Published: November 2016

Three-dimensional (3D) network-like graphitic carbon nitride nanobelts (g-C3N4 NBs) were facilely achieved by the hydrothermal treatment of bulk g-C3N4 in a medium strong oxalic acid solution (1 M, pH 0.89).
Fe2O3-decorated millimeter-long vertically aligned carbon nanotube arrays as advanced anode materials for asymmetric supercapacitors with high energy and power densities
Authors: Zhang Wenkang , Zhao Bin , Yin Yaolong , Yin Tong , Cheng Junye , Zhan Ke , Yan Ya , Yang Junhe , Li Jianqiang
Published: November 2016

An asymmetric supercapacitor with extremely high energy and power densities has been developed by using the novel Fe2O3/VACNTs anode.
Solution-processed black phosphorus/PCBM hybrid heterojunctions for solar cells
Authors: Bai Linyi , Sun Liqun , Wang Yang , Liu Zhizhou , Gao Qiang , Xiang Huijing , Xie Haiming , Zhao Yanli
Published: November 2016

Two hybrid heterojunctions consisting of black phosphorus and phenyl-C61-butyric acid methyl ester were developed for the first time and showed high performances in solar cells.
Crystalline Cu-silicide stabilizes the performance of a high capacity Si-based Li-ion battery anode
Authors: Ma Wenqing , Liu Xizheng , Wang Xi , Wang Zhifeng , Zhang Ruie , Yuan Zhihao , Ding Yi
Published: November 2016

Metal-silicides have demonstrated bright prospects as advanced anodes for lithium-ion batteries (LIBs).
AIE opens new applications in super-resolution imaging
Authors: Zhou Jiong , Yu Guocan , Huang Feihe
Published: November 2016

In a recent work, Tang and co-workers reported a new class of photoactivatable fluorescence turn-on AIE-based bioprobes which can be used for super-resolution imaging of mitochondria. This result opens a new door in the field of super-resolution imaging for developing a novel AIE-based bioprobe with high on–off contrast and a fast photoswitching rate.
Persistent and photo-stimulated luminescence in Ce3+/Cr3+ activated Y3Al2Ga3O12 phosphors and transparent phosphor-in-glass
Authors: Chen Daqin , Zhou Yang , Xu Wei , Zhong Jiasong , Huang Ping
Published: November 2016

Ce3+/Cr3+ activated Y3Al2Ga3O12 phosphors and transparent phosphor-in-glass show bright persistent and photostimulated upconversion luminescence.
All-organic liquid crystalline radicals with a spin unit in the outer position of a bent-core system
Authors: Bajzíková K. , Kohout M. , Tarábek J. , Svoboda J. , Novotná V. , Vejpravová J. , Pociecha D. , Gorecka E.
Published: November 2016

All-organic paramagnetic liquid crystals offer the advantage of a long-range order of liquid crystalline phases and the magnetic properties of the individual molecules.
Progression towards high efficiency perovskite solar cells via optimisation of the front electrode and blocking layer
Authors: Yates Heather M. , Afzaal Mohammad , Walter Arnaud , Hodgkinson John L. , Moon Soo-Jin , Sacchetto Davide , Bräuninger Matthias , Niesen Björn , Nicolay Sylvain , McCarthy Melissa , Pemble Martyn E. , Povey Ian M. , Ballif Christophe
Published: November 2016

Tailoring the properties of F-doped tin oxide, titanium dioxide and perovskite to lead to solar cells with efficiencies >16%.
Muscle-Cooling Intervention to Reduce Fatigue and Fatigue-Induced Tremor in Novice and Experienced Surgeons: A Preliminary Investigation
Authors: Jensen Lauren , Dancisak Michael , Korndorffer James
Published: November 2016

A localized, intermittent muscle-cooling protocol was implemented to determine cooling garment efficacy in reducing upper extremity muscular fatigue and tremor in novice (n = 10) and experienced surgeons (n = 9). Subjects wore a muscle-cooling garment while performing multiple trials of a forearm exercise and paired suturing task to induce muscular fatigue and exercise-induced tremor. A reduction in tremor amplitude and an extension in time to fatigue were expected with muscle cooling as compared with control trials. Each subject completed an intervention session (5°C cooling condition) and a control session (32°C or thermal neutral condition). A paired samples t test indicated that tremor amplitude was significantly reduced (t [8] = 1.89458; p < 0.05) in experienced surgeons in two dimensions (up and down, and back and forth). Tremor amplitude was reduced in novice surgeons but the effect was not significant. Time to fatigue and suture time improved in both cohorts with muscle cooling, but the effect did not reach significance. Results from the pilot work suggest muscle cooling as an intervention for reduction of fatigue and tremor is very promising, warranting further investigation. Surgical specialties that require prolonged procedures might benefit more from this intervention.
Multi-energy SXR cameras for magnetically confined fusion plasmas (invited)
Authors: Delgado-Aparicio L. F. , Maddox J. , Pablant N. , Hill K. , Bitter M. , Rice J. E. , Granetz R. , Hubbard A. , Irby J. , Greenwald M. , Marmar E. , Tritz K. , Stutman D. , Stratton B. , Efthimion P.
Published: November 2016

A compact multi-energy soft x-ray camera has been developed for time, energy and space-resolved measurements of the soft-x-ray emissivity in magnetically confined fusion plasmas. Multi-energy soft x-ray imaging provides a unique opportunity for measuring, simultaneously, a variety of important plasma properties (Te, nZ, ΔZeff, and ne,fast). The electron temperature can be obtained by modeling the slope of the continuum radiation from ratios of the available brightness and inverted radial emissivity profiles over multiple energy ranges. Impurity density measurements are also possible using the line-emission from medium- to high-Z impurities to separate the background as well as transient levels of metal contributions. This technique should be explored also as a burning plasma diagnostic in-view of its simplicity and robustness.
Performance of a large-scale barrier discharge plume improved by an upstream auxiliary barrier discharge
Authors: Li Xuechen , Chu Jingdi , Zhang Qi , Zhang Panpan , Jia Pengying , Geng Jinling
Published: November 2016

Enhanced by an upstream auxiliary dielectric barrier discharge (ADBD), a transverse barrier discharge plume with a fairly large scale is generated downstream of a narrow slit. Electrical and optical characteristics are compared for the two discharges with and without the ADBD. Results indicate that the plume with the ADBD is longer, more uniform, and dissipates a higher power. Moreover, its inception voltage is much lower. High-speed imaging presents that the uniform plasma plume with the ADBD comprises a series of moving micro-discharge filaments in a glow regime, which are much smoother than those without the ADBD.
Formation of atomically ordered and chemically selective Si—O—Ti monolayer on Si0.5Ge0.5(110) for a MIS structure via H2O2(g) functionalization
Authors: Park Sang Wook , Choi Jong Youn , Siddiqui Shariq , Sahu Bhagawan , Galatage Rohit , Yoshida Naomi , Kachian Jessica , Kummel Andrew C.
Published: November 2016

Si0.5Ge0.5(110) surfaces were passivated and functionalized using atomic H, hydrogen peroxide (H2O2), and either tetrakis(dimethylamino)titanium (TDMAT) or titanium tetrachloride (TiCl4) and studied in situ with multiple spectroscopic techniques. To passivate the dangling bonds, atomic H and H2O2(g) were utilized and scanning tunneling spectroscopy (STS) demonstrated unpinning of the surface Fermi level. The H2O2(g) could also be used to functionalize the surface for metal atomic layer deposition. After subsequent TDMAT or TiCl4 dosing followed by a post-deposition annealing, scanning tunneling microscopy demonstrated that a thermally stable and well-ordered monolayer of TiOx was deposited on Si0.5Ge0.5(110), and X-ray photoelectron spectroscopy verified that the interfaces only contained Si—O—Ti bonds and a complete absence of GeOx. STS measurements confirmed a TiOx monolayer without mid-gap and conduction band edge states, which should be an ideal ultrathin insulating layer in a metal-insulator-semiconductor structure. Regardless of the Ti precursors, the final Ti density and electronic structure were identical since the Ti bonding is limited by the high coordination of Ti to O.
Nanoribbons: From fundamentals to state-of-the-art applications
Authors: Yagmurcukardes M. , Peeters F. M. , Senger R. T. , Sahin H.
Published: November 2016

Atomically thin nanoribbons (NRs) have been at the forefront of materials science and nanoelectronics in recent years. State-of-the-art research on nanoscale materials has revealed that electronic, magnetic, phononic, and optical properties may differ dramatically when their one-dimensional forms are synthesized. The present article aims to review the recent advances in synthesis techniques and theoretical studies on NRs. The structure of the review is organized as follows: After a brief introduction to low dimensional materials, we review different experimental techniques for the synthesis of graphene nanoribbons (GNRs) with their advantages and disadvantages. In addition, theoretical investigations on width and edge-shape-dependent electronic and magnetic properties, functionalization effects, and quantum transport properties of GNRs are reviewed. We then devote time to the NRs of the transition metal dichalcogenides (TMDs) family. First, various synthesis techniques, E-field-tunable electronic and magnetic properties, and edge-dependent thermoelectric performance of NRs of MoS2 and WS2 are discussed. Then, strongly anisotropic properties, growth-dependent morphology, and the weakly width-dependent bandgap of ReS2 NRs are summarized. Next we discuss TMDs having a T-phase morphology such as TiSe2 and stable single layer NRs of mono-chalcogenides. Strong edge-type dependence on characteristics of GaS NRs, width-dependent Seebeck coefficient of SnSe NRs, and experimental analysis on the stability of ZnSe NRs are reviewed. We then focus on the most recently emerging NRs belonging to the class of transition metal trichalcogenides which provide ultra-high electron mobility and highly anisotropic quasi-1D properties. In addition, width-, edge-shape-, and functionalization-dependent electronic and mechanical properties of blackphosphorus, a monoatomic anisotropic material, and studies on NRs of group IV elements (silicene, germanene, and stanene) are reviewed. Observation of substrate-independent quantum well states, edge and width dependent properties, the topological phase of silicene NRs are reviewed. In addition, H2 concentration-dependent transport properties and anisotropic dielectric function of GeNRs and electric field and strain sensitive I–V characteristics of SnNRs are reviewed. We review both experimental and theoretical studies on the NRs of group III–V compounds. While defect and N-termination dependent conductance are highlighted for boron nitride NRs, aluminum nitride NRs are of importance due to their dangling bond, electric field, and strain dependent electronic and magnetic properties. Finally, superlattice structure of NRs of GaN/AlN, Si/Ge, G/BN, and MoS2/WS2 is reviewed.
Universal handheld micropipette
Authors: Beroz Justin , Hart A. John
Published: November 2016

The handheld micropipette is the most ubiquitous instrument for precision handling of microliter-milliliter liquid volumes, which is an essential capability in biology and chemistry laboratories. The range of one pipette is typically adjustable up to 10-fold its minimum volume, requiring the use and maintenance of multiple pipettes for liquid handling across larger ranges. Here we propose a design for a single handheld pipette adjustable from 0.1 μl to 1000 μl (i.e., 104-fold) which spans the range of an entire suite of current commercial pipettes. This is accomplished by placing an elastic diaphragm between the existing pipette body and tip, thereby de-amplifying its native volume range while maintaining its simple manual operating procedure. For proof-of-concept, we adapted a commercial pipette (100–1000 μl nominal range) with a selection of rubber sheets to function as the diaphragms and confirmed the accuracy and precision of drawn volumes are within international ISO-8655 standards across the entire 104-fold volume range. The presence of the diaphragms introduces a nonlinear mechanical behavior and a time-dependency due to heat transfer, however, by model and experiment, these are redressed so as to maintain the pipette’s accuracy and precision.
Hydration of potassium iodide dimer studied by photoelectron spectroscopy and ab initio calculations
Authors: Li Ren-Zhong , Zeng Zhen , Hou Gao-Lei , Xu Hong-Guang , Zhao Xiang , Gao Yi Qin , Zheng Wei-Jun
Published: November 2016

We measured the photoelectron spectra of (KI)2−(H2O)n (n = 0-3) and conducted ab initio calculations on (KI)2−(H2O)n anions and their corresponding neutrals up to n = 6. Two types of spectral features are observed in the experimental spectra of (KI)2−(H2O) and (KI)2−(H2O)2, indicating that two types of isomers coexist, in which the high EBE feature corresponds to the hydrated chain-like (KI)2− while the low EBE feature corresponds to the hydrated pyramidal (KI)2−. In (KI)2−(H2O)3, the (KI)2− unit prefers a pyramidal configuration, and one of the K–I distances is elongated significantly, thus a K atom is firstly separated out from the (KI)2− unit. As for the neutrals, the bare (KI)2 has a rhombus structure, and the structures of (KI)2(H2O)n are evolved from the rhombus (KI)2 unit by the addition of H2O. When the number of water molecules reaches 4, the K–I distances have significant increment and one of the I atoms prefers to leave the (KI)2 unit. The comparison of (KI)2(H2O)n and (NaI)2(H2O)n indicates that it is slightly more difficult to pry apart (KI)2 than (NaI)2 via hydration, which is in agreement with the lower solubility of KI compared to that of NaI.
Perturbation and coupling of microcavity plasmas through charge injected into an intervening microchannel
Authors: Wang Y. , Ni J. H. , Zhong S. , Cai S. , Zhang X. , Liu C. , Park S.-J. , Eden J. G.
Published: November 2016

Coupling between two microcavity plasmas in a symmetric, microfabricated dielectric barrier structure has been observed by injecting charge from one of the plasmas into an intervening microchannel. Periodic modulation of the electric field strength in the injector (or electron “donor”) cavity has the effect of deforming the acceptor microplasma which exhibits two distinct and stable spatiotemporal modes. Throughout the time interval in which the two microplasmas are coupled electrostatically, the acceptor plasma is elongated and displaced by 75–100 μm (∼30% of its diameter) in the direction of the microchannel. The depletion of charge in the microchannel results in an immediate transition of the second (acceptor) microplasma to an equilibrium state in which the plasma is azimuthally symmetric and centered within its microcavity. Switching between these two spatial modes requires a shift (in the plasma centroid) of ∼80 μm in <50 ns which corresponds to a velocity of 1.6 km/s. Precise control of this plasma phase transition through device fabrication, and modulation of the donor plasma electric field, suggest applications of this plasma coupling and charge transport mechanism to signal processing, photonics, and electromagnetics.
Information management in DNA replication modeled by directional, stochastic chains with memory
Authors: Arias-Gonzalez J. Ricardo
Published: November 2016

Stochastic chains represent a key variety of phenomena in many branches of science within the context of information theory and thermodynamics. They are typically approached by a sequence of independent events or by a memoryless Markov process. Stochastic chains are of special significance to molecular biology, where genes are conveyed by linear polymers made up of molecular subunits and transferred from DNA to proteins by specialized molecular motors in the presence of errors. Here, we demonstrate that when memory is introduced, the statistics of the chain depends on the mechanism by which objects or symbols are assembled, even in the slow dynamics limit wherein friction can be neglected. To analyze these systems, we introduce a sequence-dependent partition function, investigate its properties, and compare it to the standard normalization defined by the statistical physics of ensembles. We then apply this theory to characterize the enzyme-mediated information transfer involved in DNA replication under the real, non-equilibrium conditions, reproducing measured error rates and explaining the typical 100-fold increase in fidelity that is experimentally found when proofreading and edition take place. Our model further predicts that approximately 1 kT has to be consumed to elevate fidelity in one order of magnitude. We anticipate that our results are necessary to interpret configurational order and information management in many molecular systems within biophysics, materials science, communication, and engineering.
Kinetic stability and energetics of simulated glasses createdby constant pressure cooling
Authors: Staley Hannah , Flenner Elijah , Szamel Grzegorz
Published: November 2016

We use computer simulations to study the cooling rate dependence of the stability and energetics of model glasses created at constant pressure conditions and compare the results with glasses formed at constant volume conditions. To examine the stability, we determine the time it takes for a glass cooled and reheated at constant pressure to transform back into a liquid, ttrans, and calculate the stability ratio S=ttrans/τα, where τα is the equilibrium relaxation time of the liquid. We find that, for slow enough cooling rates, cooling and reheating at constant pressure results in a larger stability ratio S than for cooling and reheating at constant volume. We also compare the energetics of glasses obtained by cooling while maintaining constant pressure with those of glasses created by cooling from the same state point while maintaining constant volume. We find that cooling at constant pressure results in glasses with lower average potential energy and average inherent structure energy. We note that in model simulations of the vapor deposition process, glasses are created under constant pressure conditions, and thus they should be compared to glasses obtained by constant pressure cooling.
A framework for discrete stochastic simulation on 3D moving boundary domains
Authors: Drawert Brian , Hellander Stefan , Trogdon Michael , Yi Tau-Mu , Petzold Linda
Published: November 2016

We have developed a method for modeling spatial stochastic biochemical reactions in complex, three-dimensional, and time-dependent domains using the reaction-diffusion master equation formalism. In particular, we look to address the fully coupled problems that arise in systems biology where the shape and mechanical properties of a cell are determined by the state of the biochemistry and vice versa. To validate our method and characterize the error involved, we compare our results for a carefully constructed test problem to those of a microscale implementation. We demonstrate the effectiveness of our method by simulating a model of polarization and shmoo formation during the mating of yeast. The method is generally applicable to problems in systems biology where biochemistry and mechanics are coupled, and spatial stochastic effects are critical.
Perspective: Interface generation of spin-orbit torques
Authors: Sklenar Joseph , Zhang Wei , Jungfleisch Matthias B. , Jiang Wanjun , Saglam Hilal , Pearson John E. , Ketterson John B. , Hoffmann Axel
Published: November 2016

Most of the modern spintronics developments rely on the manipulation of magnetization states via electric currents, which started with the discovery of spin transfer torque effects 20 years ago. By now, it has been realized that spin-orbit coupling provides a particularly efficient pathway for generating spin torques from charge currents. At the same time, spin-orbit effects can be enhanced at interfaces, which opens up novel device concepts. Here, we discuss two examples of such interfacial spin-orbit torques, namely, systems with inherently two-dimensional materials and metallic bilayers with strong Rashba spin-orbit coupling at their interfaces. We show how ferromagnetic resonance excited by spin-orbit torques can provide information about the underlying mechanisms. In addition, this article provides a brief overview of recent developments with respect to interfacial spin-orbit torques and an outlook of still open questions.
Superhard W0.5Ta0.5B nanowires prepared at ambient pressure
Authors: Yeung Michael T. , Akopov Georgiy , Lin Cheng-Wei , King Daniel J. , Li Rebecca L. , Sobell Zachary C. , Mohammadi Reza , Kaner Richard B.
Published: November 2016

The primary focus of superhard materials development has relied on chemical tuning of the crystal structure. While these intrinsic effects are invaluable, there is a strong possibility that hardness can be dramatically enhanced using extrinsic effects. Here, we demonstrate that the superhard metal W0.5Ta0.5B can be prepared as nanowires through flux growth. The aspect ratios of the nanowires are controlled by the concentration of boride in molten aluminum, and the nanowires grow along the boron-boron chains, confirmed via electron diffraction. This morphology inherently results from the crystal habit of borides and can inspire the development of other nanostructured materials.
Fabrication of sharp atomic force microscope probes using in situ local electric field induced deposition under ambient conditions
Authors: Temiryazev Alexei , Bozhko Sergey I. , Robinson A. Edward , Temiryazeva Marina
Published: November 2016

We demonstrate a simple method to significantly improve the sharpness of standard silicon probes for an atomic force microscope or to repair a damaged probe. The method is based on creating and maintaining a strong, spatially localized electric field in the air gap between the probe tip and the surface of conductive sample. Under these conditions, nanostructure growth takes place on both the sample and the tip. The most likely mechanism is the decomposition of atmospheric adsorbate with subsequent deposition of carbon structures. This makes it possible to grow a spike of a few hundred nanometers in length on the tip. We further demonstrate that probes obtained by this method can be used for high-resolution scanning. It is important to note that all process operations are carried out in situ, in air and do not require the use of closed chambers or any additional equipment beyond the atomic force microscope itself.
Vibration energy harvester with low resonant frequency based on flexible coil and liquid spring
Authors: Wang Y. , Zhang Q. , Zhao L. , Tang Y. , Shkel A. , Kim E. S.
Published: November 2016

This paper reports an electromagnetic vibration-energy harvester with low resonant frequency based on liquid spring composed of ferrofluid. Cylinder magnet array formed by four disc NdFeB magnets is suspended by ferrofluid in a laser-machined acrylic tube which is wrapped by flexible planar coil fabricated with microfabrication process. The magnet array and coil are aligned automatically by the ferrofluid. Restoring force when the magnet array is deviated from the balance position is proportional to the deviated distance, which makes the ferrofluid work as a liquid spring obeying Hook's law. Experimental results show that the electromagnetic energy harvester occupying 1.8 cc and weighing 5 g has a resonant frequency of 16 Hz and generates an induced electromotive force of Vrms = 2.58 mV (delivering 79 nW power into matched load of 21 Ω) from 3 g acceleration at 16 Hz.
Selective growth of fully relaxed GeSn nano-islands by nanoheteroepitaxy on patterned Si(001)
Authors: Schlykow V. , Klesse W. M. , Niu G. , Taoka N. , Yamamoto Y. , Skibitzki O. , Barget M. R. , Zaumseil P. , von Känel H. , Schubert M. A. , Capellini G. , Schroeder T.
Published: November 2016

In this letter, we explore in detail the potential of nanoheteroepitaxy to controllably fabricate high quality GeSn nano-structures and to further improve the crystallinity of GeSn alloys directly grown on Si(001). The GeSn was grown by molecular beam epitaxy at relatively high temperatures up to 750 °C on pre-patterned Si nano-pillars embedded in a SiO2 matrix. The best compromise between selective GeSn growth and homogenous Sn incorporation of 1.4% was achieved at a growth temperature of 600 °C. X-ray diffraction measurements confirmed that our growth approach results in both fully relaxed GeSn nano-islands and negligible Si interdiffusion into the core of the nanostructures. Detailed transmission electron microscopy characterizations show that only the small GeSn/Si interface area reveals defects, such as stacking faults. Importantly, the main part of the GeSn islands is defect-free and of high crystalline quality. The latter was further demonstrated by photoluminescence measurements where a clear redshift of the direct ΓC-ΓV transition was observed with increasing Sn content.
Quantum point contacts and resistive switching in Ni/NiO nanowire junctions
Authors: Oliver Sean M. , Fairfield Jessamyn A. , Bellew Allen T. , Lee Sunghun , Champlain James G. , Ruppalt Laura B. , Boland John J. , Vora Patrick M.
Published: November 2016

Metal oxide devices that exhibit resistive switching are leading candidates for non-volatile memory applications due to their potential for fast switching, low-power operation, and high device density. It is widely accepted in many systems that two-state resistive behavior arises from the formation and rupture of conductive filaments spanning the oxide layer. However, means for controlling the filament geometry, which critically influences conduction, have largely been unexamined. Here, we explore the connection between filament geometry and conductance in a model resistive switching system based on the junction of two nickel/nickel oxide core/shell nanowires. Variable temperature current-voltage measurements indicate that either wide metallic filaments or narrow semiconducting filaments can be preferentially formed by varying the current compliance during electroformation. Metallic filaments behave as a conventional metallic resistance in series with a small barrier, while semiconducting filaments behave as quantum point contacts. The ability to tune filament geometry and behavior through the electroforming process may open avenues for enhanced functionality in nanoscale memristive systems.
Decoupling and ordering of multilayer graphene on C-face 3C-SiC(111)
Authors: Bouhafs C. , Stanishev V. , Zakharov A. A. , Hofmann T. , Kühne P. , Iakimov T. , Yakimova R. , Schubert M. , Darakchieva V.
Published: November 2016

We show experimentally that few layer graphene (FLG) grown on the carbon terminated surface (C-face) of 3C-SiC(111) is composed of decoupled graphene sheets. Landau level spectroscopy on FLG graphene is performed using the infrared optical Hall effect. We find that Landau level transitions in the FLG exhibit polarization preserving selection rules and the transition energies obey a square-root dependence on the magnetic field strength. These results show that FLG on C-face 3C-SiC(111) behave effectively as a single layer graphene with linearly dispersing bands (Dirac cones) at the graphene K point. We estimate from the Landau level spectroscopy an upper limit of the Fermi energy of about 60 meV in the FLG, which corresponds to a carrier density below 2.5 × 1011 cm−2. Low-energy electron diffraction μ-LEED) reveals the presence of azimuthally rotated graphene domains with a typical size of ≤200 nm. μ-LEED mapping suggests that the azimuth rotation occurs between adjacent domains within the same sheet rather than vertically in the stack.
Impact of contact couplings on thermoelectric properties of anti, Fano, and Breit-Wigner resonant junctions
Authors: Wang Rui-Ning , Dong Guo-Yi , Wang Shu-Fang , Fu Guang-Sheng , Wang Jiang-Long
Published: November 2016

Quantum interference is a well-known phenomenon which results in unique features of the transmission spectra of molecular junctions at the nanoscale. We investigate and compare the thermoelectric properties of three types of junctions like the anti, Breit-Wigner, and Fano resonances. Due to its asymmetric line-shaped transmission function, Fano resonances lead to a larger thermoelectric figure of merit (ZT) than the symmetric anti and Breit-Wigner resonances. The occurrence of quantum interference in molecular and other nanoscale junctions is independent of contact couplings between the sandwiched molecules and left/right electrodes. However, it is found that the contact couplings determine the electric and thermoelectric performances of quantum interference junctions. In anti-resonant junctions, the Seebeck coefficient is enhanced by strong contact couplings. By contrast, for Breit-Wigner resonant junctions, this same property will increase in the weak contact coupling regime. Contrary to what is observed for anti and Breit-Wigner resonant junctions, some optimal contact couplings are found in Fano-resonant junctions for which the maximum Seebeck coefficient and ZT are obtained. Finally, thermoelectric properties are also investigated when the resonances crossover from Breit-Wigner to Fano types and, subsequently, to anti resonances.
Localized electromechanical interactions in ferroelectric P(VDF-TrFE) nanowires investigated by scanning probe microscopy
Authors: Calahorra Yonatan , Whiter Richard A. , Jing Qingshen , Narayan Vijay , Kar-Narayan Sohini
Published: November 2016

We investigate the electromechanical interactions in individual polyvinylidene fluoride-trifluoroethylene nanowires in response to localized electrical poling via a conducting atomic force microscope tip. Spatially resolved measurements of piezoelectric coefficients and elastic moduli before and after poling reveal a striking dependence on the polarity of the poling field, notably absent in thin films of the same composition. These observations are attributed to the unclamped nature of the nanowires and the inherent asymmetry in their chemical and electrical interactions with the tip and underlying substrate. Our findings provide insights into the mechanism of poling/switching in polymer nanowires critical to ferroelectric device performance.
Strong amplitude-phase coupling in submonolayer quantum dots
Authors: Herzog Bastian , Lingnau Benjamin , Kolarczik Mirco , Kaptan Yücel , Bimberg Dieter , Maaßdorf André , Pohl Udo W. , Rosales Ricardo , Schulze Jan-Hindrik , Strittmatter Andre , Weyers Markus , Woggon Ulrike , Lüdge Kathy , Owschimikow Nina
Published: November 2016

Submonolayer quantum dots promise to combine the beneficial features of zero- and two-dimensional carrier confinement. To explore their potential with respect to all-optical signal processing, we investigate the amplitude-phase coupling (α-parameter) in semiconductor optical amplifiers based on InAs/GaAs submonolayer quantum dots in ultrafast pump-probe experiments. Lateral coupling provides an efficient carrier reservoir and gives rise to a large α-parameter. Combined with a high modal gain and an ultrafast gain recovery, this makes the submonolayer quantum dots an attractive gain medium for nonlinear optical signal processing.
Analyse pragmatico-discursive des SN disloqués à droite du français parlé
Authors: Horváth Márton Gergely
Published: November 2016

The aim of this paper is to provide a corpus-based analysis of right dislocation constructions in spontaneous spoken French. Previous researches describe these constructions mainly as a possibility to signal continuation or maintenance of an already established topic relation, contrary to left dislocations that signal announcement or establishment of a new topic relation between a referent and a predication. We will show that if topic continuation or maintenance remains a frequent function of right dislocation of noun phrases, it can nevertheless encode new topic relations of referentially active or accessible entities, particularly in interrogative constructions. We will also provide some elements of analysis of right dislocation of pronouns.
La mujer hermosa y la estatua de palo de El mundo por de dentro de Francisco de Quevedo
Authors: Davenport Randi Lise
Published: November 2016

Although the fourth of Quevedo’s Dreams and Discourses (Sueños y discursos), The World from Within (El mundo por de dentro), has been characterized as one of his most ‘skeptical’ texts, few critics have explored how skepticism functions in the text. Based on my doctoral research that takes into account recent revisions of Renaissance skepticism as a ‘multi-purpose tool’ and examines the text as a Menippean satire, this article offers a new interpretation of the ‘abrupt ending’ of the princeps version where a beautiful woman is compared to a wooden statue. The underlying premise of this interpretation is that through his Menippean satire Quevedo responded to epistemological challenges of the early seventeenth century when the notion of knowledge was subject to great changes.
Expression of TLR2 and TLR4 in murine small intestine during postnatal development
Authors: Inoue Ryo , Yajima Takaji , Tsukahara Takamitsu
Published: November 2016

The important role played by the gut microbiota in host immunity is mediated, in part, through toll-like receptors (TLRs). We evaluated the postnatal changes in expression of TLR2 and TLR4 in the murine small intestine and assessed how expression is influenced by gut microbiota. The expression of TLR2 and TLR4 in the murine small intestine was highly dynamic during development. The changes were especially profound during the suckling period, with the maximal mRNA levels detected in the mid-suckling period. Immunohistochemical and flow-cytometric analyses indicated that the changes in TLR2 and TLR4 expression involve primarily epithelial cells. The germ-free mice showed minor changes in TLR2/TLR4 mRNA and TLR2 protein during the suckling period. This study demonstrated that the postnatal expression of TLR2 and TLR4 in small intestinal epithelial cells is dynamic and depends on the presence of commensal intestinal microbiota.
Attitudes Toward the Insanity Defense: Examination of the Factor Structure of Insanity Defense Attitude-Revised (IDA-R) Scale in Ghana
Authors: Adjorlolo Samuel , Abdul-Nasiru Inusah , Chan Heng Choon (Oliver) , Bentum Francis
Published: November 2016

Decades of research have revealed the potential of individuals to be partial toward defendants pleading insanity at the time of offense. This study examines the internal structure of the Insanity Defense Attitude-Revised (IDA-R) scale as well as predictors of insanity defense attitude in a Ghanaian sample ( N = 253). Using principal component analysis, we identified three distinct latent factors, two (i.e., strict liability, unprofessional behavior and safety concerns) of which corroborate the findings of previous studies, and a unique factor- expression of sympathy. Participants who were highly involved in religious activities were more likely to be sympathetic. Views regarding the causes and treatability of mental illness did not significantly predict insanity defense attitudes.
Rac and Rho compete to cooperate
Authors: Short Ben
Published: November 2016

Antagonism between RhoA and Rac1 pathways creates cell heterogeneity that aids epidermal morphogenesis.
The common mouse protozoaTritrichomonas murisalters mucosal T cell homeostasis and colitis susceptibility
Authors: Escalante Nichole K. , Lemire Paul , Cruz Tleugabulova Mayra , Prescott David , Mortha Arthur , Streutker Catherine J. , Girardin Stephen E. , Philpott Dana J. , Mallevaey Thierry
Published: November 2016

The mammalian gastrointestinal tract hosts a diverse community of microbes including bacteria, fungi, protozoa, helminths, and viruses. Through coevolution, mammals and these microbes have developed a symbiosis that is sustained through the host’s continuous sensing of microbial factors and the generation of a tolerant or pro-inflammatory response. While analyzing T cell–driven colitis in nonlittermate mouse strains, we serendipitously identified that a nongenetic transmissible factor dramatically increased disease susceptibility. We identified the protozoan Tritrichomonas muris as the disease-exacerbating element. Furthermore, experimental colonization with T. muris induced an elevated Th1 response in the cecum of naive wild-type mice and accelerated colitis in Rag1−/− mice after T cell transfer. Overall, we describe a novel cross-kingdom interaction within the murine gut that alters immune cell homeostasis and disease susceptibility. This example of unpredicted microbial priming of the immune response highlights the importance of studying trans-kingdom interactions and serves as a stark reminder of the importance of using littermate controls in all mouse research.
On the mechanisms governing gas penetration into a tokamak plasma during a massive gas injection
Authors: Nardon E. , Fil A. , Chauveau P. , Tamain P. , Guirlet R. , Koslowski H.R. , Lehnen M. , Reux C. , Saint-Laurent F.
Published: November 2016

A new 1D radial fluid code, IMAGINE, is used to simulate the penetration of gas into a tokamak plasma during a massive gas injection (MGI). The main result is that the gas is in general strongly braked as it reaches the plasma, due to mechanisms related to charge exchange and (to a smaller extent) recombination. As a result, only a fraction of the gas penetrates into the plasma. Also, a shock wave is created in the gas which propagates away from the plasma, braking and compressing the incoming gas. Simulation results are quantitatively consistent, at least in terms of orders of magnitude, with experimental data for a D
2 MGI into a JET Ohmic plasma. Simulations of MGI into the background plasma surrounding a runaway electron beam show that if the background electron density is too high, the gas may not penetrate, suggesting a possible explanation for the recent results of Reux et al in JET (2015 Nucl. Fusion
55 093013).
A Platform for Monitoring Regional Antimicrobial Resistance, Using Online Data Sources: ResistanceOpen
Authors: MacFadden Derek R. , Fisman David , Andre Jeff , Ara Yuki , Majumder Maimuna S. , Bogoch Isaac I. , Daneman Nick , Wang Annie , Vavitsas Marianna , Castellani Lucas , Brownstein John S.
Published: November 2016

Background

Our understanding of the global burden of antimicrobial resistance is limited. Complementary approaches to antimicrobial resistance surveillance are needed.

Methods

We developed a Web-based/mobile platform for aggregating, analyzing, and disseminating regional antimicrobial resistance information. Antimicrobial resistance indices from existing but disparate online sources were identified and abstracted. To validate antimicrobial resistance data, in the absence of regional comparators, US and Canadian indices were aggregated and compared to existing national and state estimates. Measures of variability of antimicrobial susceptibility were determined for the United States and Canada to evaluate magnitudes of differences within countries.

Results

Over 850 resistance indices globally were identified and abstracted, totaling >5 million isolates, from 340 unique locations. Resistance index coverage spanned 41 countries, 6 continents, 43 of 50 US states, and 8 of 10 Canadian provinces. When compared to reported values, aggregated resistance values for the United States and Canada during 2013 and 2014 demonstrated agreements ranging from 94% to 97%. For the United States, state-specific resistance estimates demonstrated an agreement of 92%. Large differences in antimicrobial susceptibility were seen within countries.

Conclusions

Using existing nontraditional data sources, we have developed a Web-based platform for aggregating antimicrobial resistance indices to support monitoring of regional antimicrobial resistance patterns.
Study of Fitness, Virulence, and Fungicide Sensitivity of Lambertella corni-maris Causing Yellow Rot on Apple
Authors: Amiri Achour , Hawkins Aaron W. , Mulvaney Katie A.
Published: November 2016

Very little is known about the biology, epidemiology, and best practices to manage Lambertella rot, a newly identified postharvest disease caused by Lambertella corni-maris on apples in the United States. In this study, we investigated the prevalence of L. corni-maris in 92 grower lots throughout Washington State in 2016, evaluated the effect of nutrient availability on L. corni-maris growth, and L. corni-maris sensitivity to pH, osmotic stress, and fungicides in vitro. We assessed pathogen aggressiveness on major apple cultivars and the efficacy of pre- and postharvest fungicides to control L. corni-maris on detached fruit. L. corni-maris was widespread and was found in 40% of the growers lots surveyed at frequencies ranging from 2 to 40% of the total decay. The fungus grew faster on acidic media such as apple juice agar and V8 agar media and was able to grow equally at pH values ranging from 3 to 7. L. corni-maris isolates showed relatively low sensitivity to osmotic stress and grew evenly at 1M KCl. All nine apple cultivars tested were susceptible to L. corni-maris, but the disease severity was significantly higher on some cultivars such as Honeycrisp, Piñata, and Gala. The baseline sensitivity of 100 L. corni-maris isolates was determined based on the effective concentration necessary to inhibit 50% mycelial growth (EC50) for fludioxonil, boscalid, pyraclostrobin + SHAM, pyrimethanil, and thiabendazole. The respective mean EC50 values were 0.07, 0.84, 1.32, 2.45, and 3.68 µg/ml. Fludioxonil and pyrimethanil applied at label rates were the only fungicides able to control L. corni-maris effectively on detached apple fruit. This study is a first step toward understanding the eco-physiological requirements for L. corni-maris to survive and cause decay on apple, assessing potential shifts in fungicide sensitivity, and enhancing Lambertella rot management. We suggest “yellow rot” as the new common name for Lambertella rot.
Latency and Persistence of ‘Candidatus Liberibacter asiaticus’ in Its Psyllid Vector, Diaphorina citri (Hemiptera: Liviidae)
Authors: Canale Maria Cristina , Tomaseto Arthur Fernando , Haddad Marineia de Lara , Della Coletta-Filho Helvécio , Lopes João Roberto Spotti
Published: November 2016

Although ‘Candidatus Liberibacter asiaticus’ (Las) is a major pathogen associated with citrus huanglongbing (HLB), some characteristics of transmission by the psyllid vector Diaphorina citri are not fully understood. We examined the latent period and persistence of transmission of Las by D. citri in a series of experiments at 25°C, in which third-instar psyllid nymphs and 1-week-old adults were confined on infected citrus for an acquisition access period (AAP), and submitted to sequential inoculation access periods (IAPs) on healthy citrus seedlings. The median latent period (LP50, i.e., acquisition time after which 50% of the individuals can inoculate) of 16.8 and 17.8 days for psyllids that acquired Las as nymphs and adults, respectively, was determined by transferring single individuals in 48-h IAPs. Inoculation events were intermittent and randomly distributed over the IAPs, but were more frequent after acquisition by nymphs. A minimum latent period of 7 to 10 days was observed by transferring groups of 10 psyllids in 48-h IAPs, after a 96-h AAP by nymphs. Psyllids transmitted for up to 5 weeks, when submitted to sequential 1-week IAPs after a 14-day AAP as nymphs. The long latent period and persistence of transmission are indirect evidences of circulative propagation of Las in D. citri.
Occurrence and Distribution of Mating Types of Pseudoperonospora cubensis in the United States
Authors: Thomas Anna , Carbone Ignazio , Cohen Yigal , Ojiambo Peter S.
Published: November 2016

During the past two decades, a resurgence of cucurbit downy mildew has occurred around the world, resulting in severe disease epidemics. In the United States, resurgence of the disease occurred in 2004 and several hypotheses, including introduction of a new genetic recombinant or pathotype of the pathogen, have been suggested as potential causes for this resurgence. Occurrence and distribution of mating types of Pseudoperonospora cubensis in the United States were investigated using 40 isolates collected from cucurbits across 11 states from 2005 to 2013. Pairing of unknown isolates with known mating-type tester strains on detached leaves of cantaloupe or cucumber resulted in oospore formation 8 to 10 days after inoculation. Isolates differed in their ability to form oospores across all coinoculation pairings, with oospore numbers ranging from 280 to 1,000 oospores/cm2 of leaf tissue. Oospores were hyaline to golden-yellow, spherical, and approximately 36 μm in diameter. Of the 40 isolates tested, 24 were found to be of the A1 mating type, while 16 were of the A2 mating type. Mating type was significantly (P < 0.0001) associated with host type, whereby all isolates collected from cucumber were of the A1 mating type, while isolates from squash and watermelon were of the A2 mating type. Similarly, mating type was significantly (P = 0.0287) associated with geographical region, where isolates from northern-tier states of Michigan, New Jersey, New York, and Ohio were all A1, while isolates belonging to either A1 or A2 mating type were present in equal proportions in southern-tier states of Alabama, Florida, Georgia, North Carolina, South Carolina, and Texas. Viability assays showed that oospores were viable and, on average, approximately 40% of the oospores produced were viable as determined by the plasmolysis method. This study showed that A1 and A2 mating types of P. cubensis are present and the pathogen could potentially reproduce sexually in cucurbits within the United States. In addition, the production of viable oospores reported in this study suggests that oospores could have an important role in the biology of P. cubensis and could potentially influence the epidemiology of cucurbit downy mildew in the United States.