bluuebunny/crossref_metadata_2025 huggingface dataset:
Triple‐band compact circularly polarised stacked microstrip antenna over reactive impedance meta‐surface for GPS applications
Authors: Agarwal Kush , Nasimuddin  , Alphones Arokiaswami
Published: July 2014

In this study, a compact, triple‐band, circularly polarised stacked microstrip antenna is proposed over the artificial eta‐surface called reactive impedance surface (RIS) for enhancing antenna radiation efficiency for GPS applications. The proposed design utilises the concept of combining multi‐stacked patches with RIS as imaginary‐impedance metamaterial‐ground‐plane for selective frequency reduction of lower bands with improvement in antenna radiation properties for multi‐band applications. The circularly polarised (CP) radiation with compact antenna size is achieved for triple‐band GPS frequencies of L1 (1.575 GHz), L2 (1.227 GHz) and L5 (1.176 GHz) by placing three stacked patches with two different pairs of symmetric slits, four different sized symmetric cross‐shaped slots and truncated corners over RIS. As RIS meta‐surface reduces the wave penetration through the lossy substrate beneath it, the proposed stacked patch antenna over RIS demonstrates enhanced forward gain with suppressed back radiation. The measured results for antenna prototype are (1.168–1.185 GHz): L5 band, (1.2–1.245 GHz): L2 band and (1.51–1.59 GHz): L1 band for 10 dB return loss bandwidth with good CP radiation. Forward (boresight) right‐handed CP gain of 2.88 dBic (L5 band), 3.25 dBic (L2 band) and 5.53 dBic (L1 band) is observed for compact antenna overall volume of 0.32λo × 0.32λo × 0.024λo at 1.2 GHz.
Systematic study on G‐protein couple receptor prototypes: did they really evolve from prokaryotic genes?
Authors: Zhang Zaichao , Jin Zhong , Zhao Yongbing , Zhang Zhewen , Li Rujiao , Xiao Jingfa , Wu Jiayan
Published: July 2014

G‐protein couple receptor (GPCR) is one of the most striking examples of signalling proteins and it is only observed in eukaryotes. Based on various GPCR identification methods and classification systems, several evolutionary presumptions of different GPCR families have been reported. However, the prototype of GPCR still limits our knowledge. By investigating its structure and domain variance, the authors propose that GPCR might be evolved from prokaryotic world. The results given by the authors indicate that metabotropic glutamate receptor family would be the ancestor of GPCR. Phylogenetic analysis hints that one of metabotropic glutamate receptor GABA is possibly formed and evolved from the ancient chemical union of bacteriorhodopsin and periplasmic binding protein. The results obtained by the authors also unprecedentedly demonstrate that specific domains and identical structures are shown in each type of GPCR, which provides unique opportunities for future strategies on GPCR orphans’ prediction and classification.
Accurate molecular structures and infrared spectra of trans-2,3-dideuterooxirane, methyloxirane, and trans-2,3-dimethyloxirane
Authors: Barone Vincenzo , Biczysko Malgorzata , Bloino Julien , Puzzarini Cristina
Published: July 2014

Oxirane derivatives are the most used benchmarks for chiroptical spectroscopies in view of their small size and relative rigidity. The molecular structure, vibrational harmonic and anharmonic frequencies, and infrared intensities of the ground electronic states are analyzed in this paper. Equilibrium structure and harmonic force fields have been evaluated by means of high-level quantum-chemical calculations at the coupled-cluster level including single and double excitations together with a perturbative treatment of triples (CCSD(T)). Extrapolation to the complete basis-set limit as well as core-correlation effects have also been taken into account. Anharmonic contributions have been computed at the CCSD(T)/cc-pVTZ level for trans-2,3-dideuterooxirane. These data can serve as references to evaluate the accuracy of less expensive computational approaches rooted in the density functional theory (DFT). The latter have been used within hybrid CC/DFT approaches, which have been applied to simulate fully anharmonic infrared (IR) spectra. Finally, the best theoretical estimates of the equilibrium structures and vibrational wavenumbers are compared to the most accurate experimental data and show in all cases very good agreement, i.e., within 0.001 Å, 0.1 deg, 10 cm−1, and 0.5 km mol−1, for bond lengths, angles, wavenumbers, and IR intensities, respectively.
Ultrafast vibrational dynamics of ${\rm BH}_{4}^-$ BH 4− ions in liquid and crystalline environments
Authors: Tyborski Tobias , Costard Rene , Woerner Michael , Elsaesser Thomas
Published: July 2014

Ultrafast vibrational dynamics of \documentclass[12pt]{minimal}\begin{document}${\rm BH}_4^-$\end{document} BH 4− ions, the key units in boron hydride materials for hydrogen storage, are studied in diluted polar liquid solution and in NaBH4 crystallites by femtosecond infrared spectroscopy. Two-color pump-probe experiments reveal v = 1 lifetimes of 3 ps for the asymmetric \documentclass[12pt]{minimal}\begin{document}${\rm BH}_4^-$\end{document} BH 4− stretching mode ν3 and of 3.6 ps for the asymmetric bending mode ν4 in the solvent isopropylamine. We provide direct evidence for the \documentclass[12pt]{minimal}\begin{document}${\rm BH}_4^-$\end{document} BH 4− stretching relaxation pathway via the asymmetric bending mode ν4 by probing the latter after femtosecond excitation of ν3. Pump-probe traces measured in the crystalline phase show signatures of radiative coupling between the densely packed \documentclass[12pt]{minimal}\begin{document}${\rm BH}_4^-$\end{document} BH 4− oscillators, most clearly manifested in an accelerated subpicosecond depopulation of the v = 1 state of the ν4 mode. The radiative decay is followed by incoherent vibrational relaxation similar to the liquid phase. The excess energy released in the relaxation processes of the \documentclass[12pt]{minimal}\begin{document}${\rm BH}_4^-$\end{document} BH 4− intramolecular modes is transferred into the environment with thermal pump-probe signals being much more pronounced in the dense solid than in the diluted solution.
Magnetic diagnostics for equilibrium reconstruction and realtime plasma control in NSTX-Upgrade
Authors: Gerhardt S. P. , Erickson K. , Kaita R. , Lawson J. , Mozulay R. , Mueller D. , Que W. , Rahman N. , Schneider H. , Smalley G. , Tresemer K.
Published: July 2014

This paper describes aspects of magnetic diagnostics for realtime control in National Spherical Torus Experiment-Upgrade (NSTX-U). The sensor arrangement on the upgraded center column is described. New analog and digital circuitry for processing the plasma current Rogowski data are presented. An improved algorithm for estimating the plasma vertical velocity for feedback control is presented.
Generalized q-deformed Tamm-Dancoff oscillator algebra and associated coherent states
Authors: Chung Won Sang , Hounkonnou Mahouton Norbert , Arjika Sama
Published: July 2014

In this paper, we propose a full characterization of a generalized q-deformed Tamm-Dancoff oscillator algebra and investigate its main mathematical and physical properties. Specifically, we study its various representations and find the condition satisfied by the deformed q-number to define the algebra structure function. Particular Fock spaces involving finite and infinite dimensions are examined. A deformed calculus is performed as well as a coordinate realization for this algebra. A relevant example is exhibited. Associated coherent states are constructed. Finally, some thermodynamics aspects are computed and discussed.
Frequency up-conversion in nonpolar a-plane GaN/AlGaN based multiple quantum wells optimized for applications with silicon solar cells
Authors: Radosavljević S. , Radovanović J. , Milanović V. , Tomić S.
Published: July 2014

We have described a method for structural parameters optimization of GaN/AlGaN multiple quantum well based up-converter for silicon solar cells. It involves a systematic tuning of individual step quantum wells by use of the genetic algorithm for global optimization. In quantum well structures, the up-conversion process can be achieved by utilizing nonlinear optical effects based on intersubband transitions. Both single and double step quantum wells have been tested in order to maximize the second order susceptibility derived from the density matrix formalism. The results obtained for single step wells proved slightly better and have been further pursued to obtain a more complex design, optimized for conversion of an entire range of incident photon energies.
Topological phase transition and quantum spin Hall state in TlBiS2
Authors: Singh Bahadur , Lin Hsin , Prasad R. , Bansil A.
Published: July 2014

We have investigated the bulk and surface electronic structures and band topology of TlBiS2 as a function of strain and electric field using ab-initio calculations. In its pristine form, TlBiS2 is a normal insulator, which does not support any non-trivial surface states. We show however that a compressive strain along the (111) direction induces a single band inversion with Z2 = (1;000), resulting in a Dirac cone surface state with a large in-plane spin polarization. Our analysis shows that a critical point lies between the normal and topological phases where the dispersion of the 3D bulk Dirac cone at the Γ-point becomes nearly linear. The band gap in thin films of TlBiS2 can be tuned through an out-of-the-plane electric field to realize a topological phase transition from a trivial insulator to a quantum spin Hall state. An effective k·p model Hamiltonian is presented to simulate our first-principles results on TlBiS2.
Diagnosing residual motion via the x-ray self emission from indirectly driven inertial confinement implosions
Authors: Pak A. , Field J. E. , Benedetti L. R. , Caggiano J. , Hatarik R. , Izumi N. , Khan S. F. , Knauer J. , Ma T. , Spears B. K. , Town R. P. J. , Bradley D. K.
Published: July 2014

In an indirectly driven implosion, non-radial translational motion of the compressed fusion capsule is a signature of residual kinetic energy not coupled into the compressional heating of the target. A reduction in compression reduces the peak pressure and nuclear performance of the implosion. Measuring and reducing the residual motion of the implosion is therefore necessary to improve performance and isolate other effects that degrade performance. Using the gated x-ray diagnostic, the x-ray Bremsstrahlung emission from the compressed capsule is spatially and temporally resolved at x-ray energies of >8.7 keV, allowing for measurements of the residual velocity. Here details of the x-ray velocity measurement and fitting routine will be discussed and measurements will be compared to the velocities inferred from the neutron time of flight detectors.
A novel investigation on carbon nanotube/ZnO, Ag/ZnO and Ag/carbon nanotube/ZnO nanowires junctions for harvesting piezoelectric potential on textile
Authors: Khan Azam , Edberg Jesper , Nur Omer , Willander Magnus
Published: July 2014

In the present work, three junctions were fabricated on textile fabric as an alternative substrate for harvesting piezoelectric potential. First junction was formed on ordinary textile as (textile/multi-walled carbon nanotube film/zinc oxide nanowires (S1: T/CNTs/ZnO NWs)) and the other two were formed on conductive textile with the following layer sequence: conductive textile/zinc oxide nanowires (S2: CT/ZnO NWs) and conductive textile/multi-walled carbon nanotubes film/zinc oxide nanowires (S3: CT/CNTs/ZnO NWs). Piezoelectric potential was harvested by using atomic force microscopy in contact mode for the comparative analysis of the generated piezoelectric potential. ZnO NWs were synthesized by using the aqueous chemical growth method. Surface analysis of the grown nanostructures was performed by using scanning electron microscopy and transmission electron microscopy. The growth orientation and crystalline size were studied by using X-ray diffraction technique. This study reveals that textile as an alternative substrate have many features like cost effective, highly flexible, nontoxic, light weight, soft, recyclable, reproducible, portable, wearable, and washable for nanogenerators fabrication with acceptable performance and with a wide choice of modification for obtaining large amount of piezoelectric potential.

At the request of the editor and publisher this article is being retracted effective 6 September 2022.
Thermodynamic and mechanical properties of TiC from ab initio calculation
Authors: Dang D. Y. , Fan J. L. , Gong H. R.
Published: July 2014

The temperature-dependent thermodynamic and mechanical properties of TiC are systematically investigated by means of a combination of density-functional theory, quasi-harmonic approximation, and thermal electronic excitation. It is found that the quasi-harmonic Debye model should be pertinent to reflect thermodynamic properties of TiC, and the elastic properties of TiC decease almost linearly with the increase of temperature. Calculations also reveal that TiC possesses a pronounced directional pseudogap across the Fermi level, mainly due to the strong hybridization of Ti 3d and C 2p states. Moreover, the strong covalent bonding of TiC would be enhanced (reduced) with the decrease (increase) of temperature, while the change of volume (temperature) should have negligible effect on density of states at the Fermi level. The calculated results agree well with experimental observations in the literature.
Communication: Double-hybrid functionals from adiabatic-connection: The QIDH model
Authors: Brémond Éric , Sancho-García Juan Carlos , Pérez-Jiménez Ángel José , Adamo Carlo
Published: July 2014

A new approach stemming from the adiabatic-connection (AC) formalism is proposed to derive parameter-free double-hybrid (DH) exchange-correlation functionals. It is based on a quadratic form that models the integrand of the coupling parameter, whose components are chosen to satisfy several well-known limiting conditions. Its integration leads to DHs containing a single parameter controlling the amount of exact exchange, which is determined by requiring it to depend on the weight of the MP2 correlation contribution. Two new parameter-free DHs functionals are derived in this way, by incorporating the non-empirical PBE and TPSS functionals in the underlying expression. Their extensive testing using the GMTKN30 benchmark indicates that they are in competition with state-of-the-art DHs, yet providing much better self-interaction errors and opening a new avenue towards the design of accurate double-hybrid exchange-correlation functionals departing from the AC integrand.
Investigation of Pb/PbS a positive Schottky junction formed on conductive glass in contact with alkaline solution
Authors: Heidaripour A. , Jafarian M. , Gobal F. , Mahjani M. G. , Miandari S.
Published: July 2014

PbS on Pb thin film (Pb/PbS) was deposited on conductive glass (CG) substrate (CG/Pb/PbS) using electrochemical techniques to investigate the Schottky junction in solution. The CG/Pb/PbS electrode was investigated by different techniques based on thermionic emission theory. Electrochemical cell consisted of the CG/Pb/PbS as a working electrode in an alkaline solution showed character of the Schottky junction. Reduction and oxidation of H2O on the CG/Pb/PbS electrode were enhanced under illumination. Water photo splitting is the main process. Study of linear sweep voltammetry at around open circuit potential (OCP) allowed proposing a model based on the Schottky junction which is charged at potentials more positive than OCP and discharged at potentials more negative than OCP. Electrochemical impedance spectroscopy confirmed the capacitive nature of the Schottky junction.
Effect of cadmium selenide quantum dots on the dielectric and physical parameters of ferroelectric liquid crystal
Authors: Singh D. P. , Gupta S. K. , Manohar R. , Varia M. C. , Kumar S. , Kumar A.
Published: July 2014

The effect of cadmium selenide quantum dots (CdSe QDs) on the dielectric relaxation and material constants of a ferroelectric liquid crystal (FLC) has been investigated. Along with the characteristic Goldstone mode, a new relaxation mode has been induced in the FLC material due to the presence of CdSe QDs. This new relaxation mode is strongly dependent on the concentration of CdSe QDs but is found to be independent of the external bias voltage and temperature. The material constants have also been modified remarkably due to the presence of CdSe QDs. The appearance of this new relaxation phenomenon has been attributed to the concentration dependent interaction between CdSe QDs and FLC molecules.
Angular dependence of hysteresis shift in oblique deposited ferromagnetic/antiferromagnetic coupled bilayers
Authors: Oliveira A. B. , Rodriguez-Suarez R. L. , Michea S. , Vega H. , Azevedo A. , Rezende S. M. , Aliaga C. , Denardin J.
Published: July 2014

The angular dependence of the hysteresis shift has been investigated in ferromagnetic/antiferromagnetic (NiFe/IrMn) bilayers grown by oblique deposition under the influence of a static magnetic field applied perpendicular to the uniaxial anisotropy direction induced during the growth process. It was found that at low oblique deposition angles, the unidirectional anisotropy field is much greater than the uniaxial anisotropy field and the corresponding anisotropies directions are noncollinear. In these conditions, the angular dependence of the hysteresis loop shift exhibits the well know cosine like shape but demanding a phase shift. Contrary to this, at high oblique deposition angle (70°), the uniaxial anisotropy plays the fundamental role and the anisotropies directions are collinear. In this case, the exchange bias displays a jump phenomenon. The numerical calculations are consistent with the experimental data obtained from magneto-optical Kerr effect and ferromagnetic resonance.
Investigation of relativistic runaway electrons in electron cyclotron resonance heating discharges on Korea Superconducting Tokamak Advanced Research
Authors: Kang C. S. , Lee S. G.
Published: July 2014

The behavior of relativistic runaway electrons during Electron Cyclotron Resonance Heating (ECRH) discharges is investigated in the Korea Superconducting Tokamak Advanced Research device. The effect of the ECRH on the runaway electron population is discussed. Observations on the generation of superthermal electrons during ECRH will be reported, which will be shown to be consistent with existing theory for the development of a superthermal electron avalanche during ECRH [A. Lazaros, Phys. Plasmas 8, 1263 (2001)].
Analytical modeling of AlGaN/AlN/GaN heterostructures including effects of distributed surface donor states
Authors: Goyal Nitin , Fjeldly Tor A.
Published: July 2014

In this paper, a physics based analytical model is presented for calculation of the two-dimensional electron gas density and the bare surface barrier height of AlGaN/AlN/GaN material stacks. The presented model is based on the concept of distributed surface donor states and the self-consistent solution of Poisson equation at the different material interfaces. The model shows good agreement with the reported experimental data and can be used for the design and characterization of advanced GaN devices for power and radio frequency applications.
Improvement of charged particles transport across a transverse magnetic filter field by electrostatic trapping of magnetized electrons
Authors: Das B. K. , Hazarika P. , Chakraborty M. , Bandyopadhyay M.
Published: July 2014

A study on the transport of charged particles across a magnetic filter field has been carried out in a double plasma device (DPD) and presented in this manuscript. The DPD is virtually divided into two parts viz. source and target regions by a transverse magnetic field (TMF) which is constructed by inserting strontium ferrite magnets into two stainless steel rectangular tubes. Plasma electrons are magnetized but ions are unmagnetized inside the TMF region. Negative voltages are applied to the TMF tubes in order to reduce the loss of electrons towards them. Plasma is produced in the source region by filament discharge method and allowed to flow towards the target region through this negatively biased TMF. It is observed that in the target region, plasma density can be increased and electron temperature decreased with the help of negatively biased TMF. This observation is beneficial for negative ion source development. Plasma diffusion across the negatively biased TMF follows Bohm or anomalous diffusion process when negative bias voltage is very less. At higher negative bias, diffusion coefficient starts deviating from the Bohm diffusion value, associated with enhanced plasma flow in the target region.
Kolmogorov flow in two dimensional strongly coupled dusty plasma
Authors: Gupta Akanksha , Ganesh R. , Joy Ashwin
Published: July 2014

Undriven, incompressible Kolmogorov flow in two dimensional doubly periodic strongly coupled dusty plasma is modelled using generalised hydrodynamics, both in linear and nonlinear regime. A complete stability diagram is obtained for low Reynolds numbers R and for a range of viscoelastic relaxation time τm [0 < τm < 10]. For the system size considered, using a linear stability analysis, similar to Navier Stokes fluid (τm = 0), it is found that for Reynolds number beyond a critical R, say Rc, the Kolmogorov flow becomes unstable. Importantly, it is found that Rc is strongly reduced for increasing values of τm. A critical τmc is found above which Kolmogorov flow is unconditionally unstable and becomes independent of Reynolds number. For R < Rc, the neutral stability regime found in Navier Stokes fluid (τm = 0) is now found to be a damped regime in viscoelastic fluids, thus changing the fundamental nature of transition of Kolmogorov flow as function of Reynolds number R. A new parallelized nonlinear pseudo spectral code has been developed and is benchmarked against eigen values for Kolmogorov flow obtained from linear analysis. Nonlinear states obtained from the pseudo spectral code exhibit cyclicity and pattern formation in vorticity and viscoelastic oscillations in energy.
Platinum dendritic nanoparticles with magnetic behavior
Authors: Li Wenxian , Sun Ziqi , Tian Dongliang , Nevirkovets Ivan P. , Dou Shi-Xue
Published: July 2014

Magnetic nanoparticles have attracted increasing attention for biomedical applications in magnetic resonance imaging, high frequency magnetic field hyperthermia therapies, and magnetic-field-gradient-targeted drug delivery. In this study, three-dimensional (3D) platinum nanostructures with large surface area that features magnetic behavior have been demonstrated. The well-developed 3D nanodendrites consist of plentiful interconnected nano-arms ∼4 nm in size. The magnetic behavior of the 3D dendritic Pt nanoparticles is contributed by the localization of surface electrons due to strongly bonded oxygen/Pluronic F127 and the local magnetic moment induced by oxygen vacancies on the neighboring Pt and O atoms. The magnetization of the nanoparticles exhibits a mixed paramagnetic and ferromagnetic state, originating from the core and surface, respectively. The 3D nanodendrite structure is suitable for surface modification and high amounts of drug loading if the transition temperature was enhanced to room temperature properly.
Tailoring of crystal phase and Néel temperature of cobalt monoxides nanocrystals with synthetic approach conditions
Authors: Ravindra A. V. , Behera B. C. , Padhan P. , Lebedev O. I. , Prellier W.
Published: July 2014

Cobalt monoxide (CoO) nanocrystals were synthesized by thermal decomposition of cobalt oleate precursor in a high boiling point organic solvent 1-octadecene. The X-ray diffraction pattern and transmission electron microscopy studies suggest that pure face-centered-cubic (fcc) phase of CoO can be synthesized in the temperature range of 569–575 K. Thermolysis product at higher synthesis temperature 585 K is a mixture of fcc and hexagonal-closed-packed (hcp) phases. These nanocrystals are single crystals of CoO and exhibit mixture of two types of morphologies; one is nearly spherical with 5–25 nm diameter, and other one is 5–10 nm thick flake. The pure fcc-CoO nanocrystals show enhanced, and mixture of fcc- and hcp-CoO nanocrystals show reduced antiferromagnetic ordering temperature. Such results provide new opportunities for optimizing and enhancing the properties and performance of cobalt oxide nanomaterials.
A cesium bromide photocathode excited by 405 nm radiation
Authors: Maldonado J. R. , Cheng Y. T. , Pianetta P. , Pease Fabian W. , Hesselink L.
Published: July 2014

In several applications, such as electron beam lithography and X-ray differential phase contrast imaging, there is a need for a free electron source with a current density at least 10 A/cm2 yet can be shaped with a resolution down to 20 nm and pulsed. Additional requirements are that the source must operate in a practical demountable vacuum (>1e-9 Torr) and be reasonably compact. In prior work, a photocathode comprising a film of CsBr on metal film on a sapphire substrate met the requirements except it was bulky because it required a beam (>10 W/cm2) of 257 nm radiation. Here, we describe an approach using a 405 nm laser which is far less bulky. The 405 nm laser, however, is not energetic enough to create color centers in CsBr films. The key to our approach is to bombard the CsBr film with a flood beam of about 1 keV electrons prior to operation. Photoelectron efficiencies in the range of 100–1000 nA/mW were demonstrated with lifetimes exceeding 50 h between electron bombardments. We suspect that the electron bombardment creates intraband color centers whence electrons can be excited by the 405 nm photons into the conduction band and thence into the vacuum.
Double gated single molecular transistor for charge detection
Authors: Ray S. J. , Chowdhury R.
Published: July 2014

The electrostatic behaviour of an 1,3-Cyclobutadiene (C4H4) based Single Molecular Transistor has been investigated using the first principle calculation based on Density functional Theory and non-equilibrium Green's function approach. While the molecule is placed on top of a dielectric layer (backed by a metallic gate) and weakly coupled between the Source/Drain electrodes, the charge stability diagram revealed the presence of individual charge states in the Coulomb Blockade regime. This gets affected significantly on addition of an another gate electrode placed on the top of the molecule. This modified double-gated geometry allows additional control of the total energy of the system that is sensitive to the individual charge states of the molecule, which can be used as a charge sensing technique operational at room temperature.
Landau damping effects on dust-acoustic solitary waves in a dusty negative-ion plasma
Authors: Barman Arnab , Misra A. P.
Published: July 2014

The nonlinear theory of dust-acoustic waves (DAWs) with Landau damping is studied in an unmagnetized dusty negative-ion plasma in the extreme conditions when the free electrons are absent. The cold massive charged dusts are described by fluid equations, whereas the two-species of ions (positive and negative) are described by the kinetic Vlasov equations. A Korteweg-de Vries (KdV) equation with Landau damping, governing the dynamics of weakly nonlinear and weakly dispersive DAWs, is derived following Ott and Sudan [Phys. Fluids 12, 2388 (1969)]. It is shown that for some typical laboratory and space plasmas, the Landau damping (and the nonlinear) effects are more pronounced than the finite Debye length (dispersive) effects for which the KdV soliton theory is not applicable to DAWs in dusty pair-ion plasmas. The properties of the linear phase velocity, solitary wave amplitudes (in presence and absence of the Landau damping) as well as the Landau damping rate are studied with the effects of the positive ion to dust density ratio (μpd) as well as the ratios of positive to negative ion temperatures (σ) and masses (m).
High precision measurement of undulator polarization in the regime of hard x-rays
Authors: Marx B. , Schulze K. S. , Uschmann I. , Kämpfer T. , Wehrhan O. , Wille H. C. , Schlage K. , Röhlsberger R. , Weckert E. , Förster E. , Stöhlker T. , Paulus G. G.
Published: July 2014

We have measured the polarization purity of undulator radiation at 12.9 keV, with hitherto unachievable precision. We could measure a polarization purity of 1.8 × 10−4 by using a silicon channel-cut crystal with six Bragg reflections at 45° as analyzer.
In-situ neutron diffraction study of martensitic variant redistribution in polycrystalline Ni-Mn-Ga alloy under cyclic thermo-mechanical treatment
Authors: Li Zongbin , Zhang Yudong , Esling Claude , Gan Weimin , Zou Naifu , Zhao Xiang , Zuo Liang
Published: July 2014

The influences of uniaxial compressive stress on martensitic transformation were studied on a polycrystalline Ni-Mn-Ga bulk alloy prepared by directional solidification. Based upon the integrated in-situ neutron diffraction measurements, direct experimental evidence was obtained on the variant redistribution of seven-layered modulated (7M) martensite, triggered by external uniaxial compression during martensitic transformation. Large anisotropic lattice strain, induced by the cyclic thermo-mechanical treatment, has led to the microstructure modification by forming martensitic variants with a strong ⟨0 1 0⟩7M preferential orientation along the loading axis. As a result, the saturation of magnetization became easier to be reached.
A linear-to-circular polarization converter with half transmission and half reflection using a single-layered metamaterial
Authors: Tamayama Yasuhiro , Yasui Kanji , Nakanishi Toshihiro , Kitano Masao
Published: July 2014

A linear-to-circular polarization converter with half transmission and half reflection using a single-layered metamaterial is theoretically and numerically demonstrated. The unit cell of the metamaterial consists of two coupled split-ring resonators with identical dimensions. A theoretical analysis based on an electrical circuit model of the coupled split-ring resonators indicates that the linear-to-circular polarization converter is achieved when the magnetic coupling between the split-ring resonators is set to a certain strength. A finite-difference time-domain simulation reveals that the single-layered metamaterial behaves as the linear-to-circular polarization converter and that the polarization converter has the combined characteristics of a half mirror and a quarter-wave plate.
The Effect of Smog-Ozone Warnings and a Vanpool Program on Traffic Volume in York County of South Carolina
Authors: Giovanis Eleftherios
Published: July 2014

Ground-level ozone is a critical criteria pollutant that is significantly generated by transportation patterns. We study the effect of smog-ozone warnings, triggered by the Environmental Protection Agency, on traffic volume in York County, South Carolina during the period 2006–10. In addition, the subperiods 2006–07 and 2008–10, where the ozone smog-alert thresholds 0.080 parts per million (ppm) and 0.075 ppm, respectively, are examined. The approach followed in this paper is a differences-in-differences (DID) regression. Additionally, a regression discontinuity design in the DID framework is applied. We find a negative and significant decrease in weekday peak-hour traffic volume in the treatment group during 2008–10.
Balancing crop yield and water productivity tradeoffs in herbaceous and woody crops
Authors: Fereres Elías , Orgaz Francisco , Gonzalez-Dugo Victoria , Testi Luca , Villalobos Francisco J.
Published: July 2014

The links between water and crop yield are well known. In agricultural systems, maximum yield and maximum water productivity (WP; yield divided by water use) are not always compatible goals. In water-limited situations, optimal solutions must be reached by finding a compromise between the levels of crop production and WP. The tradeoffs between production and WP are reviewed here and the dominant effects of the environment on WP are examined. Genetic improvement for WP generally has yield tradeoffs, whereas management measures devised to improve WP also enhance yield. It is shown that partial closure of the stomata in response to environmental stimuli has a variable impact on canopy transpiration, depending on the degree of coupling between the canopy and the atmosphere. In contrast to the behaviour of the major herbaceous crops, WP increases in some woody crops in response to water stress, suggesting that biomass and transpiration are not linearly related, and that deficit irrigation should be successful in these species. Avoiding high evaporative demand periods (e.g. through tolerance to low temperatures) is an important option that aims to increase production and WP. A case study is presented for improving sunflower (Helianthus annuus L.) yield and WP in temperate environments.
Expression patterns of mitochondrial OXPHOS components, mitofusin 1 and dynamin-related protein 1 are associated with human embryo fragmentation
Authors: Otasevic Vesna , Surlan Lela , Vucetic Milica , Tulic Ivan , Buzadzic Biljana , Stancic Ana , Jankovic Aleksandra , Velickovic Ksenija , Golic Igor , Markelic Milica , Korac Aleksandra , Korac Bato
Published: July 2014

Developmental dysfunction in embryos, such as a lethal level of fragmentation, is assumed to be mitochondrial in origin. This study investigated the molecular basis of mitochondrial impairment in embryo fragmentation. Transcription patterns of factors that determine mitochondrial functionality: (i) components of the oxidative phosphorylation (OXPHOS) – complex I, cytochrome b, complex IV and ATP synthase; (ii) mitochondrial membrane potential (MMP); (iii) mitochondrial DNA (mtDNA) content and (iv) proteins involved in mitochondrial dynamics, mitofusin 1 (Mfn1) and dynamin related protein 1 (Drp1) were examined in six-cells Day 3 non-fragmented (control), low-fragmented (LF) and high-fragmented (HF) human embryos. Gene expression of mitochondria-encoded components of complex I and IV, cytochrome b and mtDNA were increased in HF embryos compared with control and LF embryos. In LF embryos, expression of these molecules was decreased compared with control and HF embryos. Both classes of fragmented embryos had decreased MMP compared with control. LF embryos had increased gene expression of Mfn1 accompanied by decreased expression of Drp1, while HF embryos had decreased Mfn1 expression but increased Drp1 expression. The study revealed that each improper transcriptional (in)activation of mitochondria-encoded components of the OXPHOS during early in vitro embryo development is associated with a decrease in MMP and with embryo fragmentation. The results also showed the importance of mitochondrial dynamics in fragmentation, at least in the extent of this process.
Effect of combined exogenous progesterone with luteotrophic support via equine chorionic gonadotrophin (eCG) on corpus luteum development, circulating progesterone concentrations and embryo development in cattle
Authors: O'Hara L. , Forde N. , Duffy P. , Randi F. , Kelly A. K. , Valenza A. , Rodriguez P. , Lonergan P.
Published: July 2014

The aim was to examine the effect of a single intramuscular (i.m.) injection of equine chorionic gonadotrophin (eCG) on Day 3 after oestrus on corpus luteum (CL) development, circulating progesterone and conceptus development in cross-bred beef heifers. In Experiment 1, heifers received: (1) saline, or a single i.m. injection of eCG on Day 3 at (2) 250 IU (3) 500 IU (4) 750 IU or (5) 1000 IU. Administration of eCG resulted in increased luteal tissue area and progesterone and oestradiol concentrations compared with controls. In Experiment 2, heifers received (1) a progesterone-releasing intravaginal device (PRID Delta) from Day 3 to 5 or (2) a PRID Delta from Day 3 to 5 plus a single injection of 750 IU eCG on Day 3. In vitro-produced blastocysts (n = 10 per recipient) were transferred on Day 7 and heifers were slaughtered on Day 14 to assess conceptus development. Administration of eCG reduced the number of short cycles (6.3% vs 31.3%) and increased mean luteal tissue weight (P = 0.02). Insertion of a PRID Delta on Day 3 resulted in an elevation (P < 0.05) in serum progesterone until removal on Day 5. Administration of eCG at the time of PRID Delta insertion resulted in higher progesterone levels (P < 0.05) from Day 10 onwards. Conceptus dimensions were not affected. In conclusion, a single injection of eCG on Day 3 increased CL size and progesterone concentrations and, when given in conjunction with a progesterone-releasing device, appeared to reduce the number of short cycles, presumably due to its luteotrophic nature. The implications of the elevated oestradiol concentrations for embryo quality require further study.
Structural effects of PrP polymorphisms on intra- and interspecies prion transmission
Authors: Angers Rachel , Christiansen Jeffrey , Nalls Amy V. , Kang Hae-Eun , Hunter Nora , Hoover Edward , Mathiason Candace K. , Sheetz Michael , Telling Glenn C.
Published: July 2014

Significance

The unpredictable recurrences of prion epidemics, their incurable lethality, and the capacity of animal prions to infect humans provide significant motivation to ascertain the parameters governing disease transmission. The unprecedented spread and uncertain zoonotic potential of chronic wasting disease, a contagious epidemic among deer, elk, and other cervids, is of particular concern. Here we demonstrate that naturally occurring primary structural differences in cervid PrPs differentially impact the efficiency of intra- and interspecies prion transmission. Our results not only deliver information about the role of primary structural variation on prion susceptibility, but also provide functional support to a mechanism in which plasticity of a tertiary structural epitope governs prion protein conversion and intra- and interspecies susceptibility to prions.
Chapter 6. The left periphery of Spanish comparative correlatives
Authors: Sánchez López Cristina
Published: July 2014

Spanish correlatives are argued to involve a predication relation articulated upon a null predicator head, both in correlatives with tanto... cuanto... ‘as... as...’ and in comparative correlatives with cuanto más/menos... (tanto) más/menos... ‘the more/less... the more/less ...’ . The predication relation guarantees that both the correlatum and the relative denote the same quantity, degree or amount. The left periphery position of the correlative sentence depends on the fronting of the correlatum into the main clause. It is proposed that the internal merge of the correlatum in FocusP allows the main clause to establish a predication relation with the correlative clause in an inverted predicate structure. Consequently, at least for comparative correlatives, the anchoring conditions of the subordinate clause in the left periphery are related to establishing a predication relation with the main clause.
Chapter 11. Fronting and irony in Spanish
Authors: Escandell-Vidal M. Victoria , Leonetti Manuel
Published: July 2014

This paper aims at explaining why irony is particularly salient in a certain kind of Spanish sentences that involve fronting of a constituent. This fact should be totally unexpected if one assumes – as we do – that irony is mainly a contextual phenomenon (Wilson & Sperber 1992 et passim). An analysis of the syntactic pattern of the examples under consideration shows that it corresponds to a specific construction where a marked word order triggers a ‘verum focus’ interpretation (Leonetti & Escandell-Vidal 2009). Our proposal is quite simple: we argue that ‘verum focus’ gives rise to emphasis, and emphasis magnifies certain aspects of meaning. Together with other grammatical devices, the ‘verum focus’ construction highlights the inappropriateness of the utterance with respect to the context in which it occurs, thus making irony a very accessible interpretive solution. The more a representation is emphasized, the easier it is for it to receive an ironic reading. This approach provides evidence in favor both of Sperber and Wilson’s proposal for irony and of our analysis of Verum Focus-Inducing Fronting in Spanish: the connection of this construction with irony cannot be understood if this kind of fronting is taken as an instance of focalization.
Chapter 12. Left periphery in discourse
Authors: Borreguero Zuloaga Margarita
Published: July 2014

In recent years a number of Romance-language scholars, have attempted to outline discourse models that identify units which contribute significantly to the information structure of discourse. One of these, known as the Basel model, is briefly presented in this paper. As far as we know, it is the only one to give an account of the structure of both oral and written texts. We will focus on the Frame Unit, an extra-predicative unit on the left periphery of the utterance with a scope that can extend beyond the single utterance. We will explore its role in text construction, observing the functions of some discourse markers when they occupy this unit. Finally, we will stress that the position of discourse markers is one of the main factors that must be taken into account in descriptive and cross-linguistic analyses of these elements.
Chapter 13. A comparative look at Focus Fronting  in Romance
Authors: Remberger Eva-Maria
Published: July 2014

The aim of this paper is to describe the syntax and semantics of Focus Fronting (FF) constructions in a range of Romance languages, including both regional and diachronic varieties, in order to reclassify these constructions on the basis of a common comparative ground. I shall begin with a look at some Sardinian data, mostly already presented in earlier research literature, since this Romance language uses FF in more contexts than other Modern Romance varieties. Sardinian not only employs FF with argumental and adjunct constituents, but also with predicates. Moreover, Sardinian FF does not necessarily yield a contrastive interpretation, as FF of constituents usually does in Italian and Spanish, but it can also encode pure Information Focus, although an emphatic value is often added. Using a set of syntactic and semantic-pragmatic properties defined principally for Sardinian, I will analyze similar FF data – Quantifier Raising (QP-fronting), Stylistic Fronting (SF), Mirative Fronting, Emphatic Focus etc. – in other Romance varieties and outline the similarities and differences found between these varieties. This will result in a systematic, descriptive overview of the crosslinguistic variation of FF found across the Romance languages.
Directed motivational current
Authors: Dörnyei Zoltán , Muir Christine , Ibrahim Zana
Published: July 2014

In this chapter, we introduce a novel psychological construct whose key aspects are well-established in major motivation theories. A Directed Motivational Current (DMC) is a conceptual framework which depicts unique periods of intensive motivational involvement both in pursuit of and fuelled by a highly valued goal/vision. The heightened motivational state of individuals or groups involved in a DMC is maintained through the deployment of a salient facilitative structure that includes reinforcing feedback loops, positive emotionality and the prospect of reaching a new level of operation. When applied in second language contexts, DMCs can energise language learners to perform beyond expectations and across several levels and timescales, including long-term engagements.
Swedish students’ beliefs about learning English in and outside of school
Authors: Henry Alastair
Published: July 2014

In Sweden students’ encounters with English in and out of school are very different. Spending around 20 hours per week in English-mediated environments outside of school, they are often engaged in richly meaningful activities. Consequently, many young people believe they learn as much of their English as a result of participation in English-mediated leisure time activities as they do from textbook-dominated classroom instruction. Drawing on emerging discussions on the ways in which learners’ beliefs about the primacy of learning English in natural environments can have negative effects on learning behaviours in formal settings (e.g. Mercer & Ryan 2010), and how learners’ beliefs about the causes of success in language learning can impact on motivation (e.g. Hsieh 2012), this chapter examines the ways in which such beliefs may impact on Swedish students’ responses to classroom learning.
Taking the floor on time
Authors: Casillas Marisa
Published: July 2014

A key part of learning to speak with others is figuring out when to start talking and how to hold the floor in conversation. For young children, the challenge of planning a linguistic response can slow down their response latencies, making misunderstanding, repair, and loss of the floor more likely. Like adults, children can mitigate their delays by using fillers (e.g., uh and um) at the start of their turns. In this chapter I analyze the onset and development of fillers in five children’s spontaneous speech from ages 1;6–3;6. My findings suggest that children start using fillers by 2;0, and use them to effectively mitigate delay in making a response.
“We call it as puppy”
Authors: Tare Medha , Gelman Susan A.
Published: July 2014

In this chapter we examine a pragmatic task that bilingual speakers face every day: determining which language to use in which conversational context (also known as “pragmatic differentiation”). We propose that pragmatic differentiation is a gradually emerging skill that requires multiple skills, including theory of mind reasoning. Two studies are described, examining pragmatic differentiation in bilingual Marathi-English language learners under varying communicative goals and contexts. These variations reveal that children’s pragmatic differentiation is dynamic and developing over the preschool years, rather than an all-or-nothing ability. Performance on these tasks seems to be influenced by concurrently developing social insights, such as theory of mind, but may also be affected by group interaction and parent talk about language differentiation.
Learning words through probabilistic inferences about speakers’ communicative intentions
Authors: Frank Michael C.
Published: July 2014

How do children learn the meanings of words? This chapter presents a probabilistic, communicative view of word learning that synthesizes insights from work on statistical learning and social learning. By describing the formal characteristics of models, it is possible to differentiate communicative models that make inferences about the speaker’s intentions from associative models that treat social information as a signal of salience. In addition, the probabilistic communicative framework can be integrated with models of pragmatic reasoning, leading to insights into how Gricean principles can facilitate word learning.
The discourse basis of the Korean copula construction in acquisition
Authors: Clancy Patricia M.
Published: July 2014

This chapter examines the discourse foundations of the Korean copula construction as it is acquired by two young children in interaction with their mothers. The findings suggest that the construction develops through gradual generalization of an initially limited set of context-specific structural schemas, and that it is profoundly sensitive to discourse factors throughout the course of development. From the outset, the realization and form of the construction’s components are shaped by the functions it serves (e.g., labeling vs. describing), the discourse-pragmatic properties of referents (e.g., given vs. new information), the interactional roles of participants (e.g., questioner vs. respondent), and the ideologies (e.g., child as conversational partner, mother as tutor and playmate) that motivate particular types of caregiver-child activities and talk.