bluuebunny/crossref_metadata_2025 huggingface dataset:
Tailoring Cross‐Cultural Competence Training
Authors: Kaufmann Hans Ruediger , Englezou Maria , García‐Gallego Ana
Published: December 2013

This study tests a new framework for capturing the different training needs required to become interculturally competent. Indications for the need for specialized training methods differentiated by target segments are provided. Many researchers have suggested that an overgeneralization of cultural differences within a proposed framework can lead to a gap between the skills being learned and the application of these skills in organizational practices. It has been also suggested that a “one‐size‐fits‐all” approach might not be effective, as various aspects of the training need to be tailored in order to fit the culture and the specific organization. Comparing the short‐term and long‐term benefits of various training options, a problem arises when an individual has learned to be competent within a particular cultural setting but, in fact, she or he is not able to transfer that knowledge and use it appropriately in another cultural setting. We used a questionnaire to test not only the dimension of intercultural competence but also the level of emotional intelligence, communication styles, and character traits and the degree of correlation of these concepts. We also compare low‐context and high‐context cultures as an attempt to distinguish different subcategories of different cultural trends and needs. © 2013 Wiley Periodicals, Inc.
Internationalization and Performance Outcomes of Entrepreneurial Family SMEs: The Role of Outside CEOs, Technology Sourcing, and Innovation
Authors: Yeoh Poh‐Lin
Published: December 2013

Previous studies suggest that the relationship between strategic change and firm performance depends on the organizational conditions under which the change is initiated and implemented. An important organizational condition that is salient in understanding the performance effect of strategic change is executive leadership. Focusing on outside succession among family businesses in an emerging economy, this study attempts to understand the role of outside chief executive officers (CEOs) on the firm's innovative and internationalization efforts. Based on interviews with 110 small and medium‐sized family companies in Malaysia, this study found that functional and process upgrading strategies depend not only on the firms’ internal and external sourcing strategies but also is moderated by the international experience of the outside CEO. Focusing on both financial and nonfinancial performance outcomes, the mediating effect of internationalization on the relationship between innovation and performance found mixed results. Findings suggest a fully mediating effect between process innovations and financial performance while a fully and partially mediating effect was observed for the relationships between product innovation and process innovation and nonfinancial performance, respectively. Finally, the interaction between international experience of outside CEOs and firm's degree of internationalization (DOI) is positively related to both financial and nonfinancial performance suggesting that the internationalization‐performance relationship is strengthened when an outside CEO possesses greater international experience. © 2013 Wiley Periodicals, Inc.
The Market Orientation–Performance Relationship: The Empirical Link in Export Ventures
Authors: Julian Craig C. , Mohamad Osman , Ahmed Zafar U. , Sefnedi S.
Published: December 2013

This study examines the empirical link between three dimensions of market orientation, namely, customer orientation, competitor orientation and interfunctional coordination, and overall export marketing performance in Indonesian export market ventures. The study was based on an empirical investigation of firms involved in exporting to foreign countries from Indonesia. The primary data for the study were collected from a self‐administered mail survey of 877 export market ventures from the manufacturing sector in Indonesia resulting in a sample of 109 usable responses being returned. From the application of the multiple regression analysis it was concluded that all three dimensions of market orientation had a significant impact on export marketing performance when measured via a composite measure of export marketing performance that included economic indicators, strategic indicators, and satisfaction with performance. © 2013 Wiley Periodicals, Inc.
A New Approach to Innovation at Nestlé R&D
Authors: Bauer Werner
Published: December 2013

This article examines a successfully implemented innovation process at Nestlé's R&D headquarters in Switzerland. The six‐year experience uses a micro‐MBA model to train Nestlé employees in how to move beyond the traditional models and innovate far beyond technology, turning them into agents of change. Using nontraditional methods, the results achieved by the program have succeeded beyond expectations. In fact, this innovation process has turned the training into a profit opportunity for the company. © 2013 Wiley Periodicals, Inc.
Photon polarization in the b → sγ processes in the left-right symmetric model
Authors: Yu Fu-Sheng , Kou Emi , Lü Cai-Dian
Published: December 2013

Abstract

The circular-polarization of the photon in the radiative B decays is dominantly left-handed in the Standard Model (SM), but the right-handed polarization may be enhanced in some new physics models with right-handed currents, such as the Left-Right Symmetric Model (LRSM). In this article, we investigate how large this wrong polarization could be within the allowed parameter space of the LRSM. We show that in the LRSM, the right-handed polarization of the photon in the b → sγ processes could be largely enhanced by the W

L
− W

R
mixing contributions because of the helicity flip on the internal top quark line of the penguin diagrams and the enhancement by the CKM factor
$ {{{V_{ts}^R}} \left/ {{V_{ts}^L}} \right.} $
. We discuss the sensitivity of the proposed methods to determine the b → sγ photon polarization to the LRSM as well as their complementary role compared to the direct search of right-handed charged gauge bosons at LHC.
Plasmon-Enhanced Fluorescence Biosensors: a Review
Authors: Bauch Martin , Toma Koji , Toma Mana , Zhang Qingwen , Dostalek Jakub
Published: December 2013

Surfaces of metallic films and metallic nanoparticles can strongly confine electromagnetic field through its coupling to propagating or localized surface plasmons. This interaction is associated with large enhancement of the field intensity and local optical density of states which provides means to increase excitation rate, raise quantum yield, and control far field angular distribution of fluorescence light emitted by organic dyes and quantum dots. Such emitters are commonly used as labels in assays for detection of chemical and biological species. Their interaction with surface plasmons allows amplifying fluorescence signal (brightness) that accompanies molecular binding events by several orders of magnitude. In conjunction with interfacial architectures for the specific capture of target analyte on a metallic surface, plasmon-enhanced fluorescence (PEF) that is also referred to as metal-enhanced fluorescence (MEF) represents an attractive method for shortening detection times and increasing sensitivity of various fluorescence-based analytical technologies. This review provides an introduction to fundamentals of PEF, illustrates current developments in design of metallic nanostructures for efficient fluorescence signal amplification that utilizes propagating and localized surface plasmons, and summarizes current implementations to biosensors for detection of trace amounts of biomarkers, toxins, and pathogens that are relevant to medical diagnostics and food control.
Plasma radiation dynamics with the upgraded Absolute Extreme Ultraviolet tomographical system in the Tokamak à Configuration Variable
Authors: Tal B. , Labit B. , Nagy D. , Chavan R. , Duval B. , Veres G.
Published: December 2013

We introduce an upgraded version of a tomographical system which is built up from Absolute Extreme Ultraviolet-type (AXUV) detectors and has been installed on the Tokamak à Configuration Variable (TCV). The system is suitable for the investigation of fast radiative processes usually observed in magnetically confined high-temperature plasmas. The upgrade consists in the detector protection by movable shutters, some modifications to correct original design errors and the improvement in the data evaluation techniques. The short-term sensitivity degradation of the detectors, which is caused by the plasma radiation itself, has been monitored and found to be severe. The results provided by the system are consistent with the measurements obtained with the usual plasma radiation diagnostics installed on TCV. Additionally, the coupling between core plasma radiation and plasma-wall interaction is revealed. This was impossible with other available diagnostics on TCV.
Multiple time step molecular dynamics in the optimized isokinetic ensemble steered with the molecular theory of solvation: Accelerating with advanced extrapolation of effective solvation forces
Authors: Omelyan Igor , Kovalenko Andriy
Published: December 2013

We develop efficient handling of solvation forces in the multiscale method of multiple time step molecular dynamics (MTS-MD) of a biomolecule steered by the solvation free energy (effective solvation forces) obtained from the 3D-RISM-KH molecular theory of solvation (three-dimensional reference interaction site model complemented with the Kovalenko-Hirata closure approximation). To reduce the computational expenses, we calculate the effective solvation forces acting on the biomolecule by using advanced solvation force extrapolation (ASFE) at inner time steps while converging the 3D-RISM-KH integral equations only at large outer time steps. The idea of ASFE consists in developing a discrete non-Eckart rotational transformation of atomic coordinates that minimizes the distances between the atomic positions of the biomolecule at different time moments. The effective solvation forces for the biomolecule in a current conformation at an inner time step are then extrapolated in the transformed subspace of those at outer time steps by using a modified least square fit approach applied to a relatively small number of the best force-coordinate pairs. The latter are selected from an extended set collecting the effective solvation forces obtained from 3D-RISM-KH at outer time steps over a broad time interval. The MTS-MD integration with effective solvation forces obtained by converging 3D-RISM-KH at outer time steps and applying ASFE at inner time steps is stabilized by employing the optimized isokinetic Nosé-Hoover chain (OIN) ensemble. Compared to the previous extrapolation schemes used in combination with the Langevin thermostat, the ASFE approach substantially improves the accuracy of evaluation of effective solvation forces and in combination with the OIN thermostat enables a dramatic increase of outer time steps. We demonstrate on a fully flexible model of alanine dipeptide in aqueous solution that the MTS-MD/OIN/ASFE/3D-RISM-KH multiscale method of molecular dynamics steered by effective solvation forces allows huge outer time steps up to tens of picoseconds without affecting the equilibrium and conformational properties, and thus provides a 100- to 500-fold effective speedup in comparison to conventional MD with explicit solvent. With the statistical-mechanical 3D-RISM-KH account for effective solvation forces, the method provides efficient sampling of biomolecular processes with slow and/or rare solvation events such as conformational transitions of hydrated alanine dipeptide with the mean life times ranging from 30 ps up to 10 ns for “flip-flop” conformations, and is particularly beneficial for biomolecular systems with exchange and localization of solvent and ions, ligand binding, and molecular recognition.
A stochastic perturbation theory for non-autonomous systems
Authors: Moon W. , Wettlaufer J. S.
Published: December 2013

We develop a perturbation theory for a class of first order nonlinear non-autonomous stochastic ordinary differential equations that arise in climate physics. The perturbative procedure produces moments in terms of integral delay equations, whose order by order decay is characterized in a Floquet-like sense. Both additive and multiplicative sources of noise are discussed and the question of how the nature of the noise influences the results is addressed theoretically and numerically. By invoking the Martingale property, we rationalize the transformation of the underlying Stratonovich form of the model to an It$\hat{\text{o}}$ô form, independent of whether the noise is additive or multiplicative. The generality of the analysis is demonstrated by developing it both for a Brownian particle moving in a periodically forced quartic potential, which acts as a simple model of stochastic resonance, as well as for our more complex climate physics model. The validity of the approach is shown by comparison with numerical solutions. The particular climate dynamics problem upon which we focus involves a low-order model for the evolution of Arctic sea ice under the influence of increasing greenhouse gas forcing ΔF0. The deterministic model, developed by Eisenman and Wettlaufer [“Nonlinear threshold behavior during the loss of Arctic sea ice,” Proc. Natl. Acad. Sci. U.S.A. 106(1), 28–32 (2009)] exhibits several transitions as ΔF0 increases and the stochastic analysis is used to understand the manner in which noise influences these transitions and the stability of the system.
Phase diagram of a reentrant gel of patchy particles
Authors: Roldán-Vargas Sándalo , Smallenburg Frank , Kob Walter , Sciortino Francesco
Published: December 2013

We study the phase diagram of a binary mixture of patchy particles which has been designed to form a reversible gel. For this we perform Monte Carlo and molecular dynamics simulations to investigate the thermodynamics of such a system and compare our numerical results with predictions based on the analytical parameter-free Wertheim theory. We explore a wide range of the temperature-density-composition space that defines the three-dimensional phase diagram of the system. As a result, we delimit the region of thermodynamic stability of the fluid. We find that for a large region of the phase diagram the Wertheim theory is able to give a quantitative description of the system. For higher densities, our simulations show that the system is crystallizing into a BCC structure. Finally, we study the relaxation dynamics of the system by means of the density and temperature dependences of the diffusion coefficient. We show that there exists a density range where the system passes reversibly from a gel to a fluid upon both heating and cooling, encountering neither demixing nor phase separation.
Electron tunneling characteristics of a cubic quantum dot, (PbS)32
Authors: Gupta Sanjeev K. , He Haiying , Banyai Douglas , Kandalam Anil K. , Pandey Ravindra
Published: December 2013

The electron transport properties of the cubic quantum dot, (PbS)32, are investigated. The stability of the quantum dot has been established by recent scanning tunneling microscope experiments [B. Kiran, A. K. Kandalam, R. Rallabandi, P. Koirala, X. Li, X. Tang, Y. Wang, H. Fairbrother, G. Gantefoer, and K. Bowen, J. Chem. Phys. 136(2), 024317 (2012)]. In spite of the noticeable energy band gap (∼2 eV), a relatively high tunneling current for (PbS)32 is predicted affirming the observed bright images for (PbS)32. The calculated I-V characteristics of (PbS)32 are predicted to be substrate-dependent; (PbS)32 on the Au (001) exhibits the molecular diode-like behavior and the unusual negative differential resistance effect, though this is not the case with (PbS)32 on the Au (110). Appearance of the conduction channels associated with the hybridized states of quantum dot and substrate together with their asymmetric distribution at the Fermi level seem to determine the tunneling characteristics of the system.
Design methodology and performance analysis of a wideband 90° phase switch for radiometer applications
Authors: Villa Enrique , Aja Beatriz , Cagigas Jaime , de la Fuente Luisa , Artal Eduardo
Published: December 2013

This paper presents the analysis, design, and characterization of a wideband 90° phase switch in Ka-band. The phase switch is based on two microstrip bandpass filters in which the commutation is performed by a novel single-pole double-throw (SPDT) switch. The analysis of π-network bandpass filters is provided, obtaining the phase difference and amplitude imbalance between filters and their scattering parameters; tested results show an average phase difference of 88.9° ± 5° and an amplitude imbalance of 0.15 dB from 24 to 37 GHz. The new broadband SPDT switch is based on a coplanar waveguide-to-slotline-to-microstrip structure, which enables a full planar integration with shifting branches. PIN diodes are used to perform the switching between outputs. The SPDT shows isolation better than 19 dB, insertion loss of around 1.8 dB, and return loss better than 15 dB. The full integration of the phase switch achieves a return loss better than 11 dB and insertion loss of around 4 dB over the band 26–36 GHz, with an average phase difference of 87.1° ± 4° and an average amplitude imbalance of 0.3 dB. It provides an excellent performance for this frequency range, suitable for radio-astronomy receivers.
ESR lineshape and 1H spin-lattice relaxation dispersion in propylene glycol solutions of nitroxide radicals – Joint analysis
Authors: Kruk D. , Hoffmann S. K. , Goslar J. , Lijewski S. , Kubica-Misztal A. , Korpała A. , Oglodek I. , Kowalewski J. , Rössler E. A. , Moscicki J.
Published: December 2013

Electron Spin Resonance (ESR) spectroscopy and Nuclear Magnetic Relaxation Dispersion (NMRD) experiments are reported for propylene glycol solutions of the nitroxide radical: 4-oxo-TEMPO-d16 containing 15N and 14N isotopes. The NMRD experiments refer to 1H spin-lattice relaxation measurements in a broad frequency range (10 kHz–20 MHz). A joint analysis of the ESR and NMRD data is performed. The ESR lineshapes give access to the nitrogen hyperfine tensor components and the rotational correlation time of the paramagnetic molecule. The NMRD data are interpreted in terms of the theory of paramagnetic relaxation enhancement in solutions of nitroxide radicals, recently presented by Kruk et al. [J. Chem. Phys. 138, 124506 (2013)]. The theory includes the effect of the electron spin relaxation on the 1H relaxation of the solvent. The 1H relaxation is caused by dipole-dipole interactions between the electron spin of the radical and the proton spins of the solvent molecules. These interactions are modulated by three dynamic processes: relative translational dynamics of the involved molecules, molecular rotation, and electron spin relaxation. The sensitivity to rotation originates from the non-central positions of the interacting spin in the molecules. The electronic relaxation is assumed to stem from the electron spin–nitrogen spin hyperfine coupling, modulated by rotation of the radical molecule. For the interpretation of the NMRD data, we use the nitrogen hyperfine coupling tensor obtained from ESR and fit the other relevant parameters. The consistency of the unified analysis of ESR and NMRD, evaluated by the agreement between the rotational correlation times obtained from ESR and NMRD, respectively, and the agreement of the translation diffusion coefficients with literature values obtained for pure propylene glycol, is demonstrated to be satisfactory.
Analytical energy gradient based on spin-free infinite-order Douglas-Kroll-Hess method with local unitary transformation
Authors: Nakajima Yuya , Seino Junji , Nakai Hiromi
Published: December 2013

In this study, the analytical energy gradient for the spin-free infinite-order Douglas-Kroll-Hess (IODKH) method at the levels of the Hartree-Fock (HF), density functional theory (DFT), and second-order Møller-Plesset perturbation theory (MP2) is developed. Furthermore, adopting the local unitary transformation (LUT) scheme for the IODKH method improves the efficiency in computation of the analytical energy gradient. Numerical assessments of the present gradient method are performed at the HF, DFT, and MP2 levels for the IODKH with and without the LUT scheme. The accuracies are examined for diatomic molecules such as hydrogen halides, halogen dimers, coinage metal (Cu, Ag, and Au) halides, and coinage metal dimers, and 20 metal complexes, including the fourth–sixth row transition metals. In addition, the efficiencies are investigated for one-, two-, and three-dimensional silver clusters. The numerical results confirm the accuracy and efficiency of the present method.
Periodic boundary conditions for QM/MM calculations: Ewald summation for extended Gaussian basis sets
Authors: Holden Zachary C. , Richard Ryan M. , Herbert John M.
Published: December 2013

An implementation of Ewald summation for use in mixed quantum mechanics/molecular mechanics (QM/MM) calculations is presented, which builds upon previous work by others that was limited to semi-empirical electronic structure for the QM region. Unlike previous work, our implementation describes the wave function's periodic images using “ChElPG” atomic charges, which are determined by fitting to the QM electrostatic potential evaluated on a real-space grid. This implementation is stable even for large Gaussian basis sets with diffuse exponents, and is thus appropriate when the QM region is described by a correlated wave function. Derivatives of the ChElPG charges with respect to the QM density matrix are a potentially serious bottleneck in this approach, so we introduce a ChElPG algorithm based on atom-centered Lebedev grids. The ChElPG charges thus obtained exhibit good rotational invariance even for sparse grids, enabling significant cost savings. Detailed analysis of the optimal choice of user-selected Ewald parameters, as well as timing breakdowns, is presented.
Minimal blow-up solutions of mass-critical inhomogeneous Hartree equation
Authors: Cao Daomin , Su Yiming
Published: December 2013

In this paper, we are concerned with the Cauchy problem of the inhomogeneous Hartree equation: \documentclass[12pt]{minimal}\begin{document}$iu_{t}= -\Delta u - k(x)\left(\int _{{\mathbb {R}}^{N}}\frac{k(y)}{|x-y|^{2}}|u(t,y)|^{2}dy\right) u(t,x)$\end{document}iut=−Δu−k(x)∫RNk(y)|x−y|2|u(t,y)|2dyu(t,x), \documentclass[12pt]{minimal}\begin{document}$x\in {\mathbb {R}}^{N}$\end{document}x∈RN, N ⩾ 3. First, we establish the mass concentration property of the blow-up solutions. Second, we show that the blow-up solutions with minimal mass should concentrate at a critical point of k. Finally, under certain assumptions on global maximum points of k we establish nonexistence of such solutions.
Lower bounds to the spectral gap of Davies generators
Authors: Temme Kristan
Published: December 2013

We construct lower bounds to the spectral gap of a family of Lindblad generators known as Davies maps. These maps describe the thermalization of quantum systems weakly coupled to a heat bath. The steady state of these systems is given by the Gibbs distribution with respect to the system Hamiltonian. The bounds can be evaluated explicitly, when the eigenbasis and the spectrum of the Hamiltonian is known. A crucial assumption is that the spectrum of the Hamiltonian is non-degenerate. Furthermore, we provide a counterexample to the conjecture, that the convergence rate is always determined by the gap of the associated Pauli master equation. We conclude that the full dynamics of the Lindblad generator has to be considered. Finally, we present several physical example systems for which the bound to the spectral gap is evaluated.
Electric potential profile of a spherical soft particle with a charged core
Authors: Phan Anh D. , Tracy Dustin A. , Nguyen T. L. Hoai , Viet N. A. , Phan The-Long , Nguyen Thanh H.
Published: December 2013

The electrostatic potential profile of a spherical soft particle is derived by solving the Poisson-Boltzmann equations on a spherical system both numerically and analytically. The soft particle is assumed to consist of an ion-permeable charged outer layer and a non-permeable charged core with constant charged density. The contribution of the core to the potential profile is calculated for different charges and dielectric constants. Our results show that the charged core heavily influences the local potential within the soft particle. By contrast, the potential distribution outside the particle in the salt solution is found to be weakly dependent on the core features. These findings are consistent with previous experiments showing the minor impact of the core of the MS2 virus on its overall electrical properties. Our studies also indicate that while a change in temperature from 290 K to 310 K only slightly varies the potential, the ionic strength in the range of 1–600 mM has a significant effect on the potential profile. Our studies would provide good understanding for experimental research in the field of biophysics and nanomedicine.
Infinitely many solutions for the nonlinear Schrödinger equations with magnetic potentials in $\mathbb {R}^{N}$RN
Authors: Liu Weiming , Wang Chunhua
Published: December 2013

In this paper, we study a nonlinear Schrödinger equations with magnetic potentials in \documentclass[12pt]{minimal}\begin{document}$\mathbb {R}^{N}$\end{document}RN involving subcritical growth. Under some decaying and weak symmetry conditions of both electric and magnetic potentials, we prove that the equation has infinitely many nonradial complex-valued solutions by applying the finite reduction method.
Precise determination of the spectroscopic g-factor by use of broadband ferromagnetic resonance spectroscopy
Authors: Shaw Justin M. , Nembach Hans T. , Silva T. J. , Boone Carl T.
Published: December 2013

We demonstrate that the spectroscopic g-factor can be determined with high precision and accuracy by broadband ferromagnetic resonance measurements and by applying an asymptotic analysis to the data. Spectroscopic data used to determine the g-factor are always obtained over a finite range of frequencies, which can result in significant errors in the fitted values. We show that by applying an asymptotic analysis to broadband datasets, precise values of the intrinsic g-factor can be determined with errors well below 1%, even when the exact form of the Kittel equation (which describes the relationship between the frequency and resonance field) is unknown. We demonstrate this methodology with measured data obtained for sputtered Ni80Fe20 (Permalloy) thin films of varied thicknesses, where we determine the bulk g-factor value to be 2.109 ± 0.003. Such an approach is further validated by application to simulated data that include both noise and an anisotropy that is not included in the Kittel equation that was used in the analysis. Finally, we show a correlation of thickness and interface structure to the magnitude of the asymptotic behavior, which provide insight into additional mechanisms that may lead to deviations from the Kittel equation.
Development and characterization of a multiple-coincidence ion-momentum imaging spectrometer
Authors: Laksman J. , Céolin D. , Månsson E. P. , Sorensen S. L. , Gisselbrecht M.
Published: December 2013

The design and performance of a high-resolution momentum-imaging spectrometer for ions which is optimized for experiments using synchrotron radiation is presented. High collection efficiency is achieved by a focusing electrostatic lens; a long drift tube improves mass resolution and a position-sensitive detector enables measurement of the transverse momentum of ions. The optimisation of the lens for particle momentum measurement at the highest resolution is described. We discuss the overall performance of the spectrometer and present examples demonstrating the momentum resolution for both kinetics and for angular measurements in molecular fragmentation for carbon monoxide and fullerenes. Examples are presented that confirm that complete space-time focussing is possible for a two-field three-dimensional imaging spectrometer.
Anomalous elastic–plastic transition of MgO under shock compression
Authors: Liu Xun , Mashimo Tsutomu , Ogata Kenichi , Kinoshita Takahiro , Sekine Toshimori , Zhou Xianming , Nellis Williams J.
Published: December 2013

The particle velocity profiles of an MgO single crystal under shock compression were measured up to a pressure of 35 GPa by a velocity interferometer system for any reflector using a LiF window combined with a powder gun. The Hugoniot-elastic limit (HEL) of MgO along the ⟨100⟩ direction was 2.9–4.3 GPa and the initial elastic waves contain some oscillations. Along the ⟨110⟩ direction, the HEL was higher than along the ⟨100⟩ direction and anomalous, two-step-structure elastic waves were observed. These characteristics are discussed based on the slip system of the MgO crystal.
Crystallographically tilted and partially strain relaxed GaN grown on inclined {111} facets etched on Si(100) substrate
Authors: Ansah Antwi K. K. , Soh C. B. , Wee Q. , Tan Rayson J. N. , Yang P. , Tan H. R. , Sun L. F. , Shen Z. X. , Chua S. J.
Published: December 2013

High resolution X-ray diffractometry (HR-XRD), Photoluminescence, Raman spectroscopy, and Transmission electron microscope measurements are reported for GaN deposited on a conventional Si(111) substrate and on the {111} facets etched on a Si(100) substrate. HR-XRD reciprocal space mappings showed that the GaN(0002) plane is tilted by about 0.63° ± 0.02° away from the exposed Si{111} growth surface for GaN deposited on the patterned Si(100) substrate, while no observable tilt existed between the GaN(0002) and Si(111) planes for GaN deposited on the conventional Si(111) substrate. The ratio of integrated intensities of the yellow to near band edge (NBE) luminescence (IYL/INBE) was determined to be about one order of magnitude lower in the case of GaN deposited on the patterned Si(100) substrate compared with GaN deposited on the conventional Si(111) substrate. The Raman E2(high) optical phonon mode at 565.224 ± 0.001 cm−1 with a narrow full width at half maximum of 1.526 ± 0.002 cm−1 was measured, for GaN deposited on the patterned Si(100) indicating high material quality. GaN deposition within the trench etched on the Si(100) substrate occurred via diffusion and mass-transport limited mechanism. This resulted in a differential GaN layer thickness from the top (i.e., 1.8 μm) of the trench to the bottom (i.e., 0.3 μm) of the trench. Mixed-type dislocation constituted about 80% of the total dislocations in the GaN grown on the inclined Si{111} surface etched on Si(100).
Ground-state magnetic phase diagram of bow-tie graphene nanoflakes in external magnetic field
Authors: Szałowski Karol
Published: December 2013

The magnetic phase diagram of a ground state is studied theoretically for graphene nanoflakes of bow-tie shape and various sizes in external in-plane magnetic field. The tight-binding Hamiltonian supplemented with Hubbard term is used to model the electronic structure of the systems in question. The existence of the antiferromagnetic phase with magnetic moments localized at the sides of the bow-tie is found for low field and a field-induced spin-flip transition to ferromagnetic state is predicted to occur in charge-undoped structures. For small nanoflake doped with a single charge carrier, the low-field phase is ferrimagnetic and a metamagnetic transition to ferromagnetic ordering can be forced by the field. The critical field is found to decrease with increasing size of the nanoflake. The influence of diagonal and off-diagonal disorder on the mentioned magnetic properties is studied. The effect of off-diagonal disorder is found to be more important than that of diagonal disorder, leading to significantly widened distribution of critical fields for disordered population of nanoflakes.
Magnetic properties of Co2−xTMxC and Co3−xTMxC nanoparticles
Authors: Qian Meichun , Khanna Shiv N.
Published: December 2013

Using synthetic chemical approaches, it is now possible to synthesize transition metal carbides nanoparticles with morphology, where the transition metal layers are embedded with intervening layers of carbon atoms. A composite material consisting of Co2C and Co3C nanoparticles has been found to exhibit unusually large coercivity and energy product. Here, we demonstrate that the magnetic moments and the anisotropy can be further enhanced by using a combination of Co and other transition metals (TM). Our studies are based on mixed nanoparticles Co2−xTMxC and Co3−xTMxC, in which selected Co sites are replaced with 3d transition elements Cr, Mn, and Fe. The studies indicate that the replacement of Co by Fe results in an increase of both the magnetic moment and the magnetic anisotropy. In particular, CoFe2C is shown to have an average spin moment of 2.56 μB and a magnetic anisotropy of 0.353 meV/formula unit compared to 1.67 μB and 0.206 meV/formula unit for the Co3C. Detailed examination of the electronic structure shows that the limited hybridization of carbon p-states with transition metal d-states drives the larger anisotropy.
Electronic transport mechanisms in scaled gate-all-around silicon nanowire transistor arrays
Authors: Clément N. , Han X. L. , Larrieu G.
Published: December 2013

Low-frequency noise is used to study the electronic transport in arrays of 14 nm gate length vertical silicon nanowire devices. We demonstrate that, even at such scaling, the electrostatic control of the gate-all-around is sufficient in the sub-threshold voltage region to confine charges in the heart of the wire, and the extremely low noise level is comparable to that of high quality epitaxial layers. Although contact noise can already be a source of poor transistor operation above threshold voltage for few nanowires, nanowire parallelization drastically reduces its impact.
Ambient-controlled scanning spreading resistance microscopy measurement and modeling
Authors: Qin Shu , Suo Zhiyong , Fillmore David , Lu Shifeng , Jeff Hu Y. , McTeer Allen
Published: December 2013

An ambient-controlled scanning spreading resistance microscopy (AC-SSRM) apparatus is utilized for one-dimensional (1D) and two-dimensional doping profiling measurement. 1D SSRM profiling on a blanket (vertical) B-doped Si wafer is conducted to obtain a spreading resistance profile SR(x). Modeling is used to convert SR(x) to carrier profile n(x). Replacing the average mobility (μ) with a calibration using μ(x), the carrier (hole) profile n(x) is more accurate. This is especially pronounced near the surface and junction depth (xj) and is consistent with the continuous anodic oxidation technique/differential Hall effect (CAOT/DHE) measured carrier profiles. The model based on AC-SSRM data obtained xj = 103.4 nm, which was consistent to secondary ion mass spectrometry results of xj = 104.0 nm. Calibrated hole dose using μ(x) is 9.6 × 1014/cm2 and is relatively closer to DHE hole dose 1.4 × 1015/cm2. In addition, a fairly good consistency of sheet resistance (RS) values among 4 point probe (4PP), CAOT/DHE, and AC-SSRM methods has been demonstrated.
Cyclic electric field stress on bipolar resistive switching devices
Authors: Schulman A. , Acha C.
Published: December 2013

We have studied the effects of accumulating cyclic electrical pulses of increasing amplitude on the non-volatile resistance state of interfaces made by sputtering a metal (Au, Pt) on top of the surface of a cuprate superconductor YBa2Cu3O7–δ. We have analyzed the influence of the number of applied pulses N on the relative amplitude of the remnant resistance change between the high (RH) and the low (RL) state [(α=(RH−RL)/RL] at different temperatures (T). We show that the critical voltage (Vc) needed to produce a resistive switching (RS, i.e., α>0) decreases with increasing N or T. We also find a power law relation between the voltage of the pulses and the number of pulses Nα0 required to produce a RS of α=α0. This relation remains very similar to the Basquin equation used to describe the stress-fatigue lifetime curves in mechanical tests. This points out to the similarity between the physics of the RS, associated with the diffusion of oxygen vacancies induced by electrical pulses, and the propagation of defects in materials subjected to repeated mechanical stress.
Characterization of interface states in Al2O3/AlGaN/GaN structures for improved performance of high-electron-mobility transistors
Authors: Hori Y. , Yatabe Z. , Hashizume T.
Published: December 2013

We have investigated the relationship between improved electrical properties of Al2O3/AlGaN/GaN metal-oxide-semiconductor high-electron-mobility transistors (MOS-HEMTs) and electronic state densities at the Al2O3/AlGaN interface evaluated from the same structures as the MOS-HEMTs. To evaluate Al2O3/AlGaN interface state densities of the MOS-HEMTs, two types of capacitance-voltage (C-V) measurement techniques were employed: the photo-assisted C-V measurement for the near-midgap states and the frequency dependent C-V characteristics for the states near the conduction-band edge. To reduce the interface states, an N2O-radical treatment was applied to the AlGaN surface just prior to the deposition of the Al2O3 insulator. As compared to the sample without the treatment, the N2O-radical treated Al2O3/AlGaN/GaN structure showed smaller frequency dispersion of the C-V curves in the positive gate bias range. The state densities at the Al2O3/AlGaN interface were estimated to be 1 × 1012 cm−2 eV−1 or less around the midgap and 8 × 1012 cm−2 eV−1 near the conduction-band edge. In addition, we observed higher maximum drain current at the positive gate bias and suppressed threshold voltage instability under the negative gate bias stress even at 150 °C. Results presented in this paper indicated that the N2O-radical treatment is effective both in reducing the interface states and improving the electrical properties of the Al2O3/AlGaN/GaN MOS-HEMTs.
The long noncoding RNA
THRIL
regulates TNFα expression through its interaction with hnRNPL
Authors: Li Zhonghan , Chao Ti-Chun , Chang Kung-Yen , Lin Nianwei , Patil Veena S. , Shimizu Chisato , Head Steven R. , Burns Jane C. , Rana Tariq M.
Published: December 2013

Significance

Genome-wide identification of changes in the expression of large intergenic noncoding RNAs (lincRNAs) in a classical model of innate immune cell activation revealed a panel of 159 lincRNAs that were highly modulated in stimulated THP1 macrophages. One of the lincRNAs, named TNFα and heterogenous nuclear ribonucleoprotein L (hnRNPL) related immunoregulatory LincRNA (THRIL), was essential for induction of TNFα, functions through a ribonucleoprotein (RNP) complex with hnRNPL, and plays an important role as regulator of physiological and pathological inflammatory immune responses.
Mutation of the palmitoylation site of estrogen receptor α in vivo reveals tissue-specific roles for membrane versus nuclear actions
Authors: Adlanmerini Marine , Solinhac Romain , Abot Anne , Fabre Aurélie , Raymond-Letron Isabelle , Guihot Anne-Laure , Boudou Frédéric , Sautier Lucile , Vessières Emilie , Kim Sung Hoon , Lière Philippe , Fontaine Coralie , Krust Andrée , Chambon Pierre , Katzenellenbogen John A. , Gourdy Pierre , Shaul Philip W. , Henrion Daniel , Arnal Jean-François , Lenfant Françoise
Published: December 2013

Significance

The in vivo roles of plasma membrane-associated estrogen receptor (ER)α, including cross-talk with nuclear ERα, are poorly understood. We created a mouse with a point mutation of the palmitoylation site of ERα (C451A-ERα) to obtain membrane-specific loss of function. A complementary mouse lacking the ERα activation function AF-2 (ERα-AF2
0
) provided selective loss of function of nuclear ERα actions. Physiologic studies revealed critical requirements for membrane receptors in ovarian function and thereby in fertility, and in vascular physiology. In contrast, nuclear ERα actions mediate uterine responses to estrogen and genome-wide analysis indicates that membrane-to-nuclear receptor cross-talk in vivo is quite modest in uterus. These findings demonstrate for the first time critical tissue-specific roles for membrane versus nuclear actions of a steroid hormone receptor in vivo.
Polynomial numerical indices of 𝐶(𝐾) and 𝐿₁(𝜇)
Authors: García Domingo , Grecu Bogdan , Maestre Manuel , Martín Miguel , Merí Javier
Published: December 2013

We estimate the polynomial numerical indices of the spaces

C
(
K
)

C(K)

and

L
1

(
μ
)

L_1(\mu )

.
Multilinear embedding – convolution estimates on smooth submanifolds
Authors: Beckner William
Published: December 2013

Multilinear embedding estimates for the fractional Laplacian are obtained in terms of functionals defined over a hyperbolic surface. Convolution estimates used in the proof enlarge the classical framework of the convolution algebra for Riesz potentials to include the critical endpoint index and provide new realizations for fractional integral inequalities that incorporate restriction to smooth submanifolds. Results developed here are modeled on the space-time estimate used by Klainerman and Machedon in their proof of uniqueness for the Gross-Pitaevskii hierarchy.
Cell cycle–regulated membrane binding of NuMA contributes to efficient anaphase chromosome separation
Authors: Zheng Zhen , Wan Qingwen , Meixiong Gerry , Du Quansheng
Published: December 2013

Accurate and efficient separation of sister chromatids during anaphase is critical for faithful cell division. It has been proposed that cortical dynein–generated pulling forces on astral microtubules contribute to anaphase spindle elongation and chromosome separation. In mammalian cells, however, definitive evidence for the involvement of cortical dynein in chromosome separation is missing. It is believed that dynein is recruited and anchored at the cell cortex during mitosis by the α subunit of heterotrimeric G protein (Gα)/mammalian homologue of Drosophila Partner of Inscuteable/nuclear mitotic apparatus (NuMA) ternary complex. Here we uncover a Gα/LGN-independent lipid- and membrane-binding domain at the C-terminus of NuMA. We show that the membrane binding of NuMA is cell cycle regulated—it is inhibited during prophase and metaphase by cyclin-dependent kinase 1 (CDK1)–mediated phosphorylation and only occurs after anaphase onset when CDK1 activity is down-regulated. Further studies indicate that cell cycle–regulated membrane association of NuMA underlies anaphase-specific enhancement of cortical NuMA and dynein. By replacing endogenous NuMA with membrane-binding-deficient NuMA, we can specifically reduce the cortical accumulation of NuMA and dynein during anaphase and demonstrate that cortical NuMA and dynein contribute to efficient chromosome separation in mammalian cells.
Protocadherin-18b interacts with Nap1 to control motor axon growth and arborization in zebrafish
Authors: Biswas Sayantanee , Emond Michelle R. , Duy Phan Q. , Hao Le T. , Beattie Christine E. , Jontes James D.
Published: December 2013

The proper assembly of neural circuits during development requires the precise control of axon outgrowth, guidance, and arborization. Although the protocadherin family of cell surface receptors is widely hypothesized to participate in neural circuit assembly, their specific roles in neuronal development remain largely unknown. Here we demonstrate that zebrafish pcdh18b is involved in regulating axon arborization in primary motoneurons. Although axon outgrowth and elongation appear normal, antisense morpholino knockdown of pcdh18b results in dose-dependent axon branching defects in caudal primary motoneurons. Cell transplantation experiments show that this effect is cell autonomous. Pcdh18b interacts with Nap1, a core component of the WAVE complex, through its intracellular domain, suggesting a role in the control of actin assembly. Like that of Pcdh18b, depletion of Nap1 results in reduced branching of motor axons. Time-lapse imaging and quantitative analysis of axon dynamics indicate that both Pcdh18b and Nap1 regulate axon arborization by affecting the density of filopodia along the shaft of the extending axon.
ILK modulates epithelial polarity and matrix formation in hair follicles
Authors: Rudkouskaya Alena , Welch Ian , Dagnino Lina
Published: December 2013

Hair follicle morphogenesis requires coordination of multiple signals and communication between its epithelial and mesenchymal constituents. Cell adhesion protein platforms, which include integrins and integrin-linked kinase (ILK), are critical for hair follicle formation. However, their precise contribution to this process is poorly understood. We show that in the absence of ILK, the hair follicle matrix lineage fails to develop, likely due to abnormalities in development of apical–basal cell polarity, as well as in laminin-511 and basement membrane assembly at the tip of the hair bud. These defects also result in impaired specification of hair matrix and absence of precortex and inner sheath root cell lineages. The molecular pathways affected in ILK-deficient follicles are similar to those in the absence of epidermal integrin β1 and include Wnt, but not sonic hedgehog, signaling. ILK-deficient hair buds also show abnormalities in the dermal papilla. Addition of exogenous laminin-511 restores morphological and molecular markers associated with hair matrix formation, indicating that ILK regulates hair bud cell polarity and functions upstream from laminin-511 assembly to regulate the developmental progression of hair follicles beyond the germ stage.
Interaction of Nck1 and PERK phosphorylated at Y561negatively modulates PERK activity and PERK regulation of pancreatic β-cell proinsulin content
Authors: Yamani Lama , Latreille Mathieu , Larose Louise
Published: December 2013

PERK, the PKR-like endoplasmic reticulum (ER) kinase, is an ER transmembrane serine/threonine protein kinase activated during ER stress. In this study, we provide evidence that the Src-homology domain–containing adaptor Nck1 negatively regulates PERK. We show that Nck directly binds to phosphorylated Y561in the PERK juxtamembrane domain through its SH2 domain. We demonstrate that mutation of Y561to a nonphosphorylatable residue (Y561F) promotes PERK activity, suggesting that PERK phosphorylation at Y561(pY561PERK) negatively regulates PERK. In agreement, we show that pY561PERK delays PERK activation and signaling during ER stress. Compatible with a role for PERK in pancreatic β-cells, we provide strong evidence that Nck1 contributes to PERK regulation of pancreatic β-cell proteostasis. In fact, we demonstrated that down-regulation of Nck1 in mouse insulinoma MIN6 cells results in faster dephosphorylation of pY561PERK, which correlates with enhanced PERK activation, increased insulin biosynthesis, and PERK-dependent increase in proinsulin content. Furthermore, we report that pancreatic islets in whole-body Nck1-knockout mice contain more insulin than control littermates. Together our data strongly suggest that Nck1 negatively regulates PERK by interacting with PERK and protecting PERK from being dephosphorylated at its inhibitory site pY561and in this way affects pancreatic β-cell proinsulin biogenesis.