bluuebunny/crossref_metadata_2025 huggingface dataset:
The impact of culture on epigenetic properties of pluripotent stem cells and pre-implantation embryos
Authors: McEwen Kirsten R. , Leitch Harry G. , Amouroux Rachel , Hajkova Petra
Published: May 2013

Cultured pluripotent stem cells hold great promise for regenerative medicine. Considerable efforts have been invested into the refinement and definition of improved culture systems that sustain self-renewal and avoid differentiation of pluripotent cells in vitro. Recent studies have, however, found that the choice of culture condition has a significant impact on epigenetic profiles of cultured pluripotent cells. Mouse and human ESCs (embryonic stem cells) show substantial epigenetic differences that are dependent on the culture condition, including global changes to DNA methylation and histone modifications and, in female human ESCs, to the epigenetic process of X chromosome inactivation. Epigenetic perturbations have also been detected during culture of pre-implantation embryos; limited research undertaken in mouse suggests a direct effect of the in vitro environment on epigenetic processes in this system. Widespread epigenetic changes induced by the culture condition in stem cells thus emphasize the necessity for extensive research into both immediate and long-term epigenetic effects of embryo culture during assisted reproductive technologies.
Kinetics of molecular transitions with dynamic disorder in single-molecule pulling experiments
Authors: Zheng Yue , Li Ping , Zhao Nanrong , Hou Zhonghuai
Published: May 2013

Macromolecular transitions are subject to large fluctuations of rate constant, termed as dynamic disorder. The individual or intrinsic transition rates and activation free energies can be extracted from single-molecule pulling experiments. Here we present a theoretical framework based on a generalized Langevin equation with fractional Gaussian noise and power-law memory kernel to study the kinetics of macromolecular transitions to address the effects of dynamic disorder on barrier-crossing kinetics under external pulling force. By using the Kramers’ rate theory, we have calculated the fluctuating rate constant of molecular transition, as well as the experimentally accessible quantities such as the force-dependent mean lifetime, the rupture force distribution, and the speed-dependent mean rupture force. Particular attention is paid to the discrepancies between the kinetics with and without dynamic disorder. We demonstrate that these discrepancies show strong and nontrivial dependence on the external force or the pulling speed, as well as the barrier height of the potential of mean force. Our results suggest that dynamic disorder is an important factor that should be taken into account properly in accurate interpretations of single-molecule pulling experiments.
The role of the (111) texture on the exchange bias and interlayer coupling effects observed in sputtered NiFe/IrMn/Co trilayers
Authors: Castro I. L. , Nascimento V. P. , Passamani E. C. , Takeuchi A. Y. , Larica C. , Tafur M. , Pelegrini F.
Published: May 2013

Magnetic properties of sputtered NiFe/IrMn/Co trilayers grown on different seed layers (Cu or Ta) deposited on Si (100) substrates were investigated by magnetometry and ferromagnetic resonance measurements. Exchange bias effect and magnetic spring behavior have been studied by changing the IrMn thickness. As shown by X-ray diffraction, Ta and Cu seed layers provoke different degrees of (111) fcc-texture that directly affect the exchange bias and indirectly modify the exchange spring coupling behavior. Increasing the IrMn thickness, it was observed that the coupling angle between the Co and NiFe ferromagnetic layers increases for the Cu seed system, but it reduces for the Ta case. The results were explained considering (i) different anisotropies of the Co and IrMn layers induced by the different degree of the (111) texture and (ii) the distinct exchange bias set at the NiFe/IrMn and IrMn/Co interfaces in both systems. The NiFe and Co interlayer coupling angle is strongly correlated with both exchange bias and exchange magnetic spring phenomena. It was also shown that the highest exchange bias field occurs when an unstressed L12 IrMn structure is stabilized.
Kelvin force microscopy characterization of charging effect in thin a-SiOxNy:H layers deposited in pulsed plasma enhanced chemical vapor deposition process by tuning the Silicon-environment
Authors: Villeneuve-Faure C. , Makasheva K. , Bonafos C. , Despax B. , Boudou L. , Pons P. , Teyssedre G.
Published: May 2013

Results from a study on the charging effect of a-SiOxNy:H thin layers are presented in this paper. Issues related to structural and electrical characterization of these layers are discussed. Spectroscopic ellipsometry was used to determine accurately the layer thickness and their optical properties, while the Kelvin Force Microscopy (KFM) was applied to characterize the local electrical properties of the layers. Obtained results reveal that by tuning the Si-environment in a-SiOxNy:H thin dielectric layers, deposited in plasma assisted process, a strong modification of the surface and volume charge conduction can be achieved. Particularly, increasing Si-content in the a-SiOxNy:H layers rises the volume conduction and charges retention. Thus, local electrical properties of thin dielectric layers can be engineered in order to meet specific requirements.
Shear banding in polymer solutions
Authors: Cromer Michael , Villet Michael C. , Fredrickson Glenn H. , Leal L. Gary
Published: May 2013

The current theoretical belief is that the steady-state shear banding in viscoelastic liquids requires a non-monotonic constitutive relationship between shear stress and shear rate. Although existing rheological studies conclude that the constitutive equation for entangled polymers is monotonic, recent experimental evidence suggests shear banding can nevertheless occur in polymer solutions. In this work, we predict, for the first time, steady state shear banding with a realistic monotonic constitutive theory for polymeric liquids. The key is that a proper account must be taken of the coupling of polymer stress to polymer concentration. We also predict multiple steady states at some shear rates as seen experimentally, with shear banding if the flow is ramped quickly enough from rest, but homogeneous linear shear flow otherwise.
Polyhedral realizations of crystal bases for quantum algebras of classical affine types
Authors: Hoshino A.
Published: May 2013

We give the explicit forms of the crystal bases B(∞) for the quantum affine algebras of types \documentclass[12pt]{minimal}\begin{document}$A^{(2)}_{2n-1}$\end{document}A2n−1(2), \documentclass[12pt]{minimal}\begin{document}$A^{(2)}_{2n}$\end{document}A2n(2), \documentclass[12pt]{minimal}\begin{document}$B^{(1)}_{n}$\end{document}Bn(1), \documentclass[12pt]{minimal}\begin{document}$C^{(1)}_{n}$\end{document}Cn(1), \documentclass[12pt]{minimal}\begin{document}$D^{(1)}_{n}$\end{document}Dn(1), and \documentclass[12pt]{minimal}\begin{document}$D^{(2)}_{n+1}$\end{document}Dn+1(2) by using the method of polyhedral realizations of crystal bases.
Cosmic-ray diffusion modeling: Solutions using variational methods
Authors: Tautz R. C. , Lerche I.
Published: May 2013

The diffusion of energetic particles in turbulent magnetic fields is usually described via the two-point, two-time velocity correlation function. A variational principle is used to determine the characteristic function that results from the Fourier-transformed correlation function. Both for a linear approximation and for the wave vector set to zero, explicit solutions are derived that depend on the Fokker-Planck coefficient of pitch-angle scattering. It is shown that, for an isotropic form of the Fokker-Planck coefficient, the characteristic function is divergent, which can be remedied only by using a Fokker-Planck coefficient that is finite at all pitch angles.
Optical response of oriented and highly anisotropic subwavelength metallic nanostructure arrays
Authors: Alvine K. J. , Bernacki B. E. , Bennett W. D. , Edwards D. J. , Mendoza A. , Suter J. D.
Published: May 2013

Here we describe the optical response of highly anisotropic subwavelength coatings with Au structures based on the open-ring-resonator and fabricated via nanoimprint lithography and metal sputtering. This approach allows fabrication of dense arrays of oriented nanostructures over large areas with a resonance in the visible wavelength range. Nanostructures are wire-like, with a nanoscale L-shaped cross section approximately 70 nm in width. The coatings exhibit a resonant transmission response that is highly angle and polarization dependent. Experimental results are presented along with complementary numerical modeling results predicting the resonance shift with corresponding changes in fabrication parameters.
Mitigation of two-plasmon decay in direct-drive inertial confinement fusion through the manipulation of ion-acoustic and Langmuir wave damping
Authors: Myatt J. F. , Vu H. X. , DuBois D. F. , Russell D. A. , Zhang J. , Short R. W. , Maximov A. V.
Published: May 2013

The extended Zakharov model of the two-plasmon decay instability in an inhomogeneous plasma [D. F. DuBois et al., Phys. Rev. Lett. 74, 3983 (1995); D. A. Russell and D. F. DuBois, Phys. Rev. Lett. 86, 428 (2001)] is further generalized to include the evolution of the electron distribution function in the quasi-linear approximation [cf., e.g., K. Y. Sanbonmatsu et al. Phys. Plasmas 7, 2824 (2000); D. A. Russell et al., paper presented at the Workshop on SRS/SBS Saturation, Wente Vineyards, Livermore, CA, 2–5 April 2002]. This makes it possible to investigate anomalous absorption of laser light and hot electron production due to the two-plasmon decay instability of multiple overlapping electromagnetic waves. Scalings of hot-electron production in the (stationary) nonlinearly saturated regime relevant to recent experiments [B. Yaakobi et al., Phys. Plasmas 19, 012704 (2012); D. H. Froula et al., Phys. Rev. Lett. 108, 165003 (2012)] have been obtained. They indicate a sensitivity to ion-acoustic wave (IAW) damping and to the collisional absorption of Langmuir waves. Such a sensitivity might be exploited in inertial confinement fusion target design by the use of mid-Z ablators.
Kinetic theory of quasi-stationary collisionless axisymmetric plasmas in the presence of strong rotation phenomena
Authors: Cremaschini Claudio , Stuchlík Zdeněk , Tessarotto Massimo
Published: May 2013

The problem of formulating a kinetic treatment for quasi-stationary collisionless plasmas in axisymmetric systems subject to the possibly independent presence of local strong velocity-shear and supersonic rotation velocities is posed. The theory is developed in the framework of the Vlasov-Maxwell description for multi-species non-relativistic plasmas. Applications to astrophysical accretion discs arising around compact objects and to plasmas in laboratory devices are considered. Explicit solutions for the equilibrium kinetic distribution function (KDF) are constructed based on the identification of the relevant particle adiabatic invariants. These are shown to be expressed in terms of generalized non-isotropic Gaussian distributions. A suitable perturbative theory is then developed which allows for the treatment of non-uniform strong velocity-shear/supersonic plasmas. This yields a series representation for the equilibrium KDF in which the leading-order term depends on both a finite set of fluid fields as well as on the gradients of an appropriate rotational frequency. Constitutive equations for the fluid number density, flow velocity, and pressure tensor are explicitly calculated. As a notable outcome, the discovery of a new mechanism for generating temperature and pressure anisotropies is pointed out, which represents a characteristic feature of plasmas considered here. This is shown to arise as a consequence of the canonical momentum conservation and to contribute to the occurrence of temperature anisotropy in combination with the adiabatic conservation of the particle magnetic moment. The physical relevance of the result and the implications of the kinetic solution for the self-generation of quasi-stationary electrostatic and magnetic fields through a kinetic dynamo are discussed.
Hot-electron generation from laser–pre-plasma interactions in cone-guided fast ignition
Authors: Li J. , Davies J. R. , Ma T. , Mori W. B. , Ren C. , Solodov A. A. , Theobald W. , Tonge J.
Published: May 2013

Two-dimensional particle-in-cell (PIC) simulations were performed for the cone-in-shell integrated fast-ignition experiments at the Omega Laser Facility [W. Theobald et al., Phys. Plasmas 18, 056305 (2011)]. The initial plasma density profile in the PIC simulations was taken from hydrodynamic simulations of the prepulse interaction with the gold cone. Hot-electron generation from laser–pre-plasma interactions and transport up to 100× the critical density (nc) was studied. The simulation showed a mean divergence half-angle of 68° and 50% absorption for the hot electrons. The simulation results show that the generated hot electrons were dominated in number by low-energy electrons but in energy by multi-MeV electrons. Electron transport between 5 and 100 nc was ballistic. In the late stage of the simulation, all the results were largely independent of polarization, indicating a stochastic hot-electron–generation mechanism.
Effects of curvature on rarefied gas flows between rotating concentric cylinders
Authors: Dongari Nishanth , White Craig , Scanlon Thomas J. , Zhang Yonghao , Reese Jason M.
Published: May 2013

The gas flow between two concentric rotating cylinders is considered in order to investigate non-equilibrium effects associated with the Knudsen layers over curved surfaces. We investigate the nonlinear flow physics in the near-wall regions using a new power-law (PL) wall-scaling approach. This PL model incorporates Knudsen layer effects in near-wall regions by taking into account the boundary limiting effects on the molecular free paths. We also report new direct simulation Monte Carlo results covering a wide range of Knudsen numbers and accommodation coefficients, and for various outer-to-inner cylinder radius ratios. Our simulation data are compared with both the classical slip flow theory and the PL model, and we find that non-equilibrium effects are not only dependent on Knudsen number and accommodation coefficient but are also significantly affected by the surface curvature. The relative merits and limitations of both theoretical models are explored with respect to rarefaction and curvature effects. The PL model is able to capture some of the nonlinear trends associated with Knudsen layers up to the early transition flow regime. The present study also illuminates the limitations of classical slip flow theory even in the early slip flow regime for higher curvature test cases, although the model does exhibit good agreement throughout the slip flow regime for lower curvature cases. Torque and velocity profile comparisons also convey that a good prediction of integral flow properties does not necessarily guarantee the accuracy of the theoretical model used, and it is important to demonstrate that field variables are also predicted satisfactorily.
Geometric approach to non-relativistic quantum dynamics of mixed states
Authors: Gimeno Vicent , Sotoca Jose M.
Published: May 2013

In this paper we propose a geometrization of the non-relativistic quantum mechanics for mixed states. Our geometric approach makes use of the Uhlmann's principal fibre bundle to describe the space of mixed states and as a novelty tool, to define a dynamic-dependent metric tensor on the principal manifold, such that the projection of the geodesic flow to the base manifold gives the temporal evolution predicted by the von Neumann equation. Using that approach we can describe every conserved quantum observable as a Killing vector field, and provide a geometric proof for the Poincaré quantum recurrence in a physical system with finite energy levels.
3-D effects on viscosity and generation of toroidal and poloidal flows in LHD
Authors: Nagaoka K. , Ida K. , Yoshinuma M. , Suzuki Y. , Kamiya K. , Satake S. , Tanaka K. , Yokoyama M. , Murakami S. , Osakabe M. , Takahashi H. , Seki R. , Suzuki C. , Narushima Y. , Nakano H. , Kisaki M. , Ikeda K. , Tsumori K. , Takeiri Y. , Kaneko O. , Yamada H. ,   LHD Experiment Group
Published: May 2013

Three-dimensional effects on plasma flows have been experimentally studied in the large helical device with 3D configurations. Spontaneous toroidal flow without net driving force using the combination of perpendicular neutral beam injection (NBI) heating and balanced tangential NBI heating has been investigated with two magnetic configurations. Co- and counter-directed spontaneous flows have been observed depending on the collisionality. Toroidal flow shear changes the sign at 0.4<reff<0.6 between co- and counter-flowing plasmas, where reff is a averaged minor radius. The detailed flow structures have been also examined at the edge region with stochastic magnetic field. A poloidal flow driven by the positive radial electric field has been observed at the open field region just outside of the plasma boundary. At the stochastic region, a shear of poloidal flow has been observed, while no shear of toroidal flow has been observed. The toroidal flow shear changes only in the nested magnetic flux surface region. A difference of density fluctuation property has been observed between co- and counter-flowing plasmas, where toroidal flow shears are formed.
Application of dynamic displacement current for diagnostics of subnanosecond breakdowns in an inhomogeneous electric field
Authors: Shao Tao , Tarasenko Victor F. , Zhang Cheng , Burachenko Alexandr G. , Rybka Dmitry V. , Kostyrya Igor’ D. , Lomaev Mikhail I. , Baksht Evgeni Kh. , Yan Ping
Published: May 2013

The breakdown of different air gaps at high overvoltages in an inhomogeneous electric field was investigated with a time resolution of up to 100 ps. Dynamic displacement current was used for diagnostics of ionization processes between the ionization wave front and a plane anode. It is demonstrated that during the generation of a supershort avalanche electron beam (SAEB) with amplitudes of ∼10 A and more, conductivity in the air gaps at the breakdown stage is ensured by the ionization wave, whose front propagates from the electrode of small curvature radius, and by the dynamic displacement current between the ionization wave front and the plane electrode. The amplitude of the dynamic displacement current measured by a current shunt is 100 times greater than the SAEB. It is shown that with small gaps and with a large cathode diameter, the amplitude of the dynamic displacement current during a subnanosecond rise time of applied pulse voltage can be higher than 4 kA.
Atomically sharp 318 nm Gd:AlGaN ultraviolet light emitting diodes on Si with low threshold voltage
Authors: Kent Thomas F. , Carnevale Santino D. , Myers Roberto C.
Published: May 2013

Self-assembled AlxGa1–xN polarization-induced nanowire light emitting diodes (PINLEDs) with Gd-doped AlN active regions are prepared by plasma-assisted molecular beam epitaxy on Si substrates. Atomically sharp electroluminescence (EL) from Gd intra-f-shell electronic transitions at 313 nm and 318 nm is observed under forward biases above 5 V. The intensity of the Gd 4f EL scales linearly with current density and increases at lower temperature. The low field excitation of Gd 4f EL in PINLEDs is contrasted with high field excitation in metal/Gd:AlN/polarization-induced n-AlGaN devices; PINLED devices offer over a three fold enhancement in 4f EL intensity at a given device bias.
Low temperature investigations and surface treatments of colloidal narrowband fluorescent nanodiamonds
Authors: Neu E. , Guldner F. , Arend C. , Liang Y. , Ghodbane S. , Sternschulte H. , Steinmüller-Nethl D. , Krueger A. , Becher C.
Published: May 2013

We report fluorescence investigations and Raman spectroscopy on colloidal nanodiamonds (NDs) obtained via bead assisted sonic disintegration (BASD) of a polycrystalline chemical vapor deposition film. The BASD NDs contain in situ created silicon vacancy (SiV) centers. Whereas many NDs exhibit emission from SiV ensembles, we also identify NDs featuring predominant emission from a single bright SiV center. We demonstrate oxidation of the NDs in air as a tool to optimize the crystalline quality of the NDs via removing damaged regions resulting in a reduced ensemble linewidth as well as single photon emission with increased purity. We furthermore investigate the temperature dependent zero-phonon-line fine-structure of a bright single SiV center as well as the polarization properties of its emission and absorption.
Effect of silane/hydrogen ratio on microcrystalline silicon thin films by remote inductively coupled plasma
Authors: Guo Y. N. , Wei D. Y. , Xiao S. Q. , Huang S. Y. , Zhou H. P. , Xu S.
Published: May 2013

Hydrogenated microcrystalline silicon (μc-Si:H) thin films were prepared by remote low frequency inductively coupled plasma (ICP) chemical vapor deposition system, and the effect of silane/hydrogen ratio on the microstructure and electrical properties of μc-Si:H films was systematically investigated. As silane/hydrogen ratio increases, the crystalline volume fraction Fc decreases and the ratio of the intensity of (220) peak to that of (111) peak drops as silane flow rate is increased. The FTIR result indicates that the μc-Si:H films prepared by remote ICP have a high optical response with a low hydrogen content, which is in favor of reducing light-induced degradation effect. Furthermore, the processing window of the phase transition region for remote ICP is much wider than that for typical ICP. The photosensitivity of μc-Si:H films can exceed 100 at the transition region and this ensures the possibility of the fabrication of microcrystalline silicon thin film solar cells with a open-circuit voltage of about 700 mV.
Origin of ferromagnetism in transition metal doped BaTiO3
Authors: Apostolova I. N. , Apostolov A. T. , Golrokh Bahoosh Safa , Wesselinowa Julia M.
Published: May 2013

We have calculated the temperature, magnetic field, and ion doping dependence of the magnetic and electric properties in Fe-doped BaTiO3 using a microscopic model and the Green's function technique. It is shown that the ferromagnetic and multiferroic properties observed at room temperature in Fe doped BaTiO3 could be due to the super exchange interactions between Fe3+ ions in different occupational sites associated with oxygen vacancies and to the exchange coupling of Fe ions with mixed valence, Fe3+ and Fe4+. There is a multiferroic region which depends strongly on the Fe-doping concentration.
Anisotropy compensation and magnetostrictive properties in Tbx Dy1−x(Fe0.9Mn0.1)1.93 Laves compounds: Experimental and theoretical analysis
Authors: Hu C. C. , Shi Y. G. , Shi D. N. , Tang S. L. , Fan J. Y. , Du Y. W.
Published: May 2013

The structure, magnetic transitions, and magnetostriction of Tbx Dy1−x(Fe0.9Mn0.1)1.93 polycrystalline compounds have been investigated. The Mn substitution for Fe changes the composition for the anisotropy compensation to the Dy-rich side compared with the Tbx Dy1−xFe2 system, which was confirmed by the analysis of detailed scanned XRD, the temperature dependence of a.c. initial susceptibility χac(T), and the calculation of the first anisotropy constant K1. The spin configuration diagram accompanied with different crystal structures for TbxDy1−x(Fe0.9Mn0.1)1.93 was constructed. The large tetragonal distortion λ100 due to the Mn substitution for Fe could be ascribed to the change in d band structure. The largest ratio between magnetostriction and the absolute values of the first anisotropy constant λa/|K1| appears at the composition with x=0.26, which could make it potential material for magnetostrictive application. Based on our experimental results, a phenomenological approach was also proposed to theoretically demonstrate that the facilitated magnetization rotation and enhanced magnetostriction are a consequence of the anisotropic flattening of Gibbs free energy.
Breathing oscillations in enlarged cylindrical-anode-layer Hall plasma accelerator
Authors: Geng S. F. , Tang D. L. , Wang C. X. , Fu R. K. Y. , Qiu X. M. , Chu Paul K.
Published: May 2013

Breathing oscillations in the discharge of an enlarged cylindrical-anode-layer Hall plasma accelerator are investigated by three-dimensional particle-in-cell (PIC) simulation. Different from the traditional breathing mode in a circular Hall plasma accelerator, the bulk plasma oscillation here is trigged by the potential barrier generated by the concentrated ion beam and substantial enough to compete with the anode voltage. The electric field near the anode is suppressed by the potential barrier thereby decreasing the electron density by ∼36%. The discharge is restored to the normal level after the concentrated beam explodes and then it completes one cycle of electro-driven breathing oscillation. The breathing mode identified by the PIC simulation has a frequency range of ∼156 kHz–∼250 kHz and does not vary monotonically with the discharge voltage.
Admittance spectroscopy in kesterite solar cells: Defect signal or circuit response
Authors: Paul Weiss Thomas , Redinger Alex , Luckas Jennifer , Mousel Marina , Siebentritt Susanne
Published: May 2013

Unlike Cu(In,Ga)Se2 based solar cells, Cu2ZnSn(S,Se)4 solar cells show a strong increase in series resistance with decreasing temperature. In this study we deduce the series resistance from temperature dependent current-voltage measurements on a 5.5% efficient Cu2ZnSnSe4 solar cell. By applying a simple circuit model an increasing series resistance with decreasing temperature alone results in a capacitance step within the C-f profile. We show that this step needs to be distinguished from a step caused by a defect state or a carrier freeze-out. Consequently, the deduced activation energy is strongly distorted by the circuit response.
Effective control on flat band voltage of epitaxial lanthanide oxide based metal oxide semiconductor capacitors by interfacial carbon
Authors: Laha Apurba , Fissel A. , Osten H. J.
Published: May 2013

Present work addresses the issue of flat band voltage instability engendered by the presence of large number of fixed charges and interface traps at and close to the interface of metal oxide semiconductor capacitors. We show that submonolayer of C incorporation onto Si surface prior to epitaxial lanthanide oxides (Ln2O3: Gd2O3, Nd2O3) deposition can significantly improve their electrical properties. Ultraviolet photoelectric spectroscopy shows that most of the intrinsic surface states that stem from the dangling bonds on Si surface disappear after passivation with C. The flat band voltage of Pt/Gd2O3/Si MOS capacitors can be tuned in a controlled manner by systematic incorporation of C onto Si surface, effectively at Gd2O3-Si interface.
Thin film bulk acoustic wave resonators tuning from first principles
Authors: Kvasov Alexander , Tagantsev Alexander K.
Published: May 2013

Being important for the antiresonance frequency tuning of tunable thin Film Bulk Acoustic wave Resonators (FBARs), the non-linear electrostrictive coefficient was for the first time calculated for BaTiO3 and SrTiO3 using ab initio methods. Further, taking into account the small difference of obtained values for BaTiO3 and SrTiO3 these results were linearly interpolated to the BaxSr1−xTiO3 (BST) compositions. The obtained values are consistent with previously made order-of-magnitude estimates. Using parameters obtained with first principles calculations, we simulated the resonance parameters of BST based tunable FBARs. Resulting antiresonance tuning was smaller than expected due to the compensation of two competing terms conditioned by linear and non-linear electrostrictions. Our calculations confirm that, for tunable FBAR modeling, it is important to use a polarization-based Landau free energy expansion taking into account both non-linear electrostriction and background permittivity.
Silver nanoparticle facilitated charge generation in tandem organic light-emitting devices
Authors: Yan Fei , Chen Rui , Sun H. D. , Wei Sun Xiao
Published: May 2013

By inserting an ultrathin silver nanoparticles (Ag NPs) layer between n- and p-type layer of charge generation connector, the performance of the tandem organic light emitting device was improved drastically; the driving voltage was lowered and the luminous efficiency was increased significantly. As the common electrode for two emissive units, Ag NP layer sits at the PN heterojunction interface responsible for charge generation and offers more charge carriers under a lower driving voltage. Additionally, the surface plasmonic resonance of Ag NPs also plays an important role on device improvement.
Ultrafast sub-threshold photo-induced response in crystalline and amorphous GeSbTe thin films
Authors: Shu M. J. , Chatzakis I. , Kuo Y. , Zalden P. , Lindenberg A. M.
Published: May 2013

Pump-probe optical reflectivity and terahertz transmission measurements have been used to investigate time resolved sub-threshold photo-induced effects in crystalline and amorphous GeSbTe films at MHz repetition rates. The reflectivity in both phases exhibits long-lived modulations consistent with the sign of the changes that occur upon switching but of smaller magnitude. These can be understood by the generation of acoustic strains with the crystalline phase response dominated by thermal effects and the amorphous phase response associated with electronically induced changes. Evidence for a photo-induced distortion is observed in the amorphous phase which develops homogeneously within the excited region on few-picosecond time scales.
Transient heat flux shielding using thermal metamaterials
Authors: Narayana Supradeep , Savo Salvatore , Sato Yuki
Published: May 2013

We have developed a heat shield based on a metamaterial engineering approach to shield a region from transient diffusive heat flow. The shield is designed with a multilayered structure to prescribe the appropriate spatial profile for heat capacity, density, and thermal conductivity of the effective medium. The heat shield was experimentally compared to other isotropic materials.
Note: A simple-structured anode exchangeable X-ray tube
Authors: Nguyen Thanh-hai , Lee Chang Jun , Park Rae-jun , Jin Gye-Hwan , Kim Sung Youb , Jeon Insu
Published: May 2013

An anode exchangeable X-ray tube of very simple structure was developed. Aluminum, chromium, and copper anode targets were prepared and used to investigate X-ray spectra. X-ray images of a thin wood plate were taken using those targets. The measured energies of the characteristic X-rays of each target agreed well with the presented results. The difference of resolution and brightness of each image was found based on MTF values and intensities. The developed X-ray tube can give high durability, and higher quality X-ray images of an arbitrary object by exchanging anode targets.
Highly efficient broadband blazed grating in resonance domain
Authors: Oliva M. , Michaelis D. , Fuchs F. , Tünnermann A. , Zeitner U. D.
Published: May 2013

A resonance domain blazed grating, composed of an effective medium structure and a subsequent mode conversion layer, is designed, fabricated, and characterized. Due to the demanding high aspect ratio geometries, a technological approach for multilevel structures, assisted by atomic layer deposition technology, has been developed. The measured efficiency of about 90% exhibits the largest value yet reported for a multi-level fused silica transmission grating in the resonance domain, operating at non Littrow mounting, close to normal incidence.
Weavable dye sensitized solar cells exploiting carbon nanotube yarns
Authors: Velten Josef , Kuanyshbekova Zharkynay , Göktepe Özer , Göktepe Fatma , Zakhidov Anvar
Published: May 2013

Weavable Dye Sensitized Solar Cells (DSSC) made with flexible yarns of conductive multiwalled carbon nanotubes (MWNTs) were produced having a power conversion efficiency above 3%. This was achieved with a specific design and careful consideration of the yarn function in the DSSC. Fermat yarns of MWNTs individually coated with mesoporous TiO2 layer were twisted together and coated with more mesoporous TiO2 to create a 3 dimensional photo electrode to overcome electron diffusion length issues. Archimedian yarns of MWNTs coated with a thin layer of platinum worked as a counter electrode to complete the architecture used in this DSSC.
A compact radiation system for L band magnetically insulated transmission line oscillator
Authors: Wang Dong , Qin Fen , Shi Mei-you , Chen Dai-Bing , Wen Jie , Jin Xiao , Xu Sha
Published: May 2013

A compact radiation system for L band magnetically insulated transmission line oscillator (MILO) is present. It consists of a coaxial TEM-TE11 mode converter and a coaxial multimode horn antenna. Some metal plates are inserted into the coaxial waveguide to divide it into several sectoral waveguides with different phase propagation constants to compose a coaxial TE11 mode. Then some of the sectoral waveguides are folded up to reduce the length of the mode converter. Multimode horn antenna is adopted to enhance aperture efficiency and power handling capability of the radiation antenna. A radiation system for a 1.58 GHz MILO device is designed with a length of 33 cm and an aperture radius of 20 cm. The gain is 15.8 dBi and aperture efficiency is 86.8 %. Both low power and high power microwave experiment is carried out to test the radiation character. The experiment test results agree well with computer simulation.
METAL COMPLEXES OF 1,10-PHENANTHROLINE DERIVATIVES V.* BIS-LIGAND IRON(II) COMPLEXES OF 1 ,10-PHENANTHROLINE-2-CARBOTHIOAMIDE
Authors: Goodwin HA , Smith FE , Konig E , Ritter G
Published: May 2013

The preparation of 1,10-phenanthroline-2-carbothioamidea nd its bis-ligand
complexes of iron(II) is described. The ligand produces a strong field and the magnetic
and Mossbauer effect data for the complexes indicate that in these the metal atom has a
1A1 ground state. The ligand can coordinate as a neutral or anionic tridentate, producing
either cationic or neutral complexes. The electronic spectra of the cationic complexes
are typical for the iron(II)-bis-terimine system and show intense charge-transfer absorption.
Infrared data indicate that the sulphur atom of the thioamido group is coordinated.
Communicating endometriosis with young women to decrease diagnosis time
Authors: Shadbolt Naomi A. , Parker Melissa A. , Orthia Lindy A.
Published: May 2013

Issues addressed

Endometriosis is estimated to affect approximately 10% of women. Although early detection may enhance health outcomes and fertility, there is a recognised diagnostic delay of 6.7 years. There are limited data on ways to discuss endometriosis with young women. The aims of the present study were to determine what young women know about endometriosis, what young women want to know about endometriosis and how this is best communicated to promote early detection.

Methods

Women aged 16–25 years were invited to complete an online survey that was advertised via Facebook, email, Twitter and flyers at high schools and a university.

Results

In all, 131 women responded to the survey. Fifty‐two percent of participants had heard of endometriosis, 89% thought teenagers should be educated about endometriosis and 78% thought that young men should also be educated about the condition. Favoured sources for obtaining information were schools (40%), the Internet (22%) and magazines (13%). Participants were most comfortable talking to a doctor (75%), parent (59%) or friend (51%). Participants primarily wanted to know about the disease, its symptoms, risk factors and treatment. Many participants' descriptions of endometriosis were vague or inaccurate.

Conclusions

The results of the present study indicate that young women are keen to learn about endometriosis, particularly its symptoms. Preferential sources of information appear to be schools or the Internet, and young women appear more comfortable talking to doctors.

So what?

To promote early detection of endometriosis, health promotion activities should direct their information towards sources that young women prefer.
Supporting patients to self-manage chronic disease: clinicians’ perspectives and current practices
Authors: Phillips Rebecca L. , Short Alison , Dugdale Paul , Nugus Peter , Greenfield David
Published: May 2013

This study investigated: clinicians’ perspectives of the scope of self-management, which self-management support initiatives are used, and the factors clinicians consider when deciding which initiative to use with individual patients. Three phases of data collection were used. First, clinicians were interviewed about their attitudes toward self-management (n = 14). Second, clinicians and managers completed a survey about the support initiatives they use (n = 38). Third, in interviews clinicians described the applications of initiatives (n = 6). Data were descriptively and thematically analysed. Clinicians believed that supporting self-management involved a holistic approach. However, some also thought that not all patients had the capacity to self-manage. This idea may be at odds with the underlying notion of self-management and impact on the support provided. Clinicians reported using 54 initiatives to support self-management and identified a range of situations when each initiative may or may not be suitable. This suggests that clinicians need to be familiar with a range of support initiatives as one will not suit everyone. Deciding which initiative is most appropriate may be aided by the development of guidelines.
Medicolegal Issues in Neuroimaging
Authors: Tovino Stacey
Published: May 2013

During the past ten years, legal theorists have focused on the impact of advances in neuroimaging for issues in criminal law, especially criminal responsibility, criminal procedure, capital punishment, and national security. This chapter identifies and examines the multiplicity of ways in which clinical neuroimaging might intersect with civil and administrative law and highlights those areas of the law that are most relevant for clinicians. In particular, advances in clinical neuroimaging can implicate tort law (including allegations of negligent neuroimaging, negligent diagnosis, and negligent misdiagnosis), contract law (including laws relating to health insurance contracts and employee benefits), federal and state mental health parity law, disability discrimination law, disability benefit law, constitutional law, and civil competency determinations.
Acoustically mediated emotional contagion as an across-species homology underlying music processing
Authors: Fritz Thomas , Koelsch Stefan
Published: May 2013

An understanding about the biological roots of music may be vital to the study of human evolution. Here we first review ideas on drumming and song as homologous traits of the human capacity for music, and then point out another possible homology of this capacity: A neurological physiology supporting acoustically mediated emotional contagion. A key aspect of this argument is that acoustically mediated emotionally contagious behaviours in our closest phylogenetic relatives (play panting and pant hoots in African great apes) are structurally and functionally related to laughter and music in humans. We conclude that the musical capacity in humans may have evolved as a response to selective pressures for increased group size for its effect of synchronizing group motivation and emotional experience through acoustically mediated emotional contagion, and as such would have promoted group gatherings, social functions and the establishment of rituals.
The Legal Effects of EU Agreements
Authors: Mendez Mario
Published: May 2013

Examining the legal effects of EU concluded treaties, this book provides an analysis of this increasingly important and rapidly growing area of EU law. The EU has concluded more than 1,000 treaties including recently its first human rights treaty (the UN Rights of Persons with Disability Convention). These agreements are regularly invoked in litigation in the Courts of the member states and before the EU courts in Luxembourg but their ramifications for the EU legal order and that of the member states remains underexplored. Through analysis of over 300 cases, the book finds evidence of a twin-track approach whereby the Court of Justice of the European Union (CJEU) adopts a maximalist approach to Treaty enforcement, where EU agreements are invoked in challenges to member state level action whilst largely insulating EU action from meaningful review vis-à-vis agreements. The book also reveals novel findings regarding the use of EU agreements in EU level litigation including: the types and which specific EU agreements (including the types of provisions) have arisen in litigation; the nature of the proceedings (preliminary rulings or direct actions) and the number of occasions in which they have been addressed in challenges to member state or EU action and the outcomes; who has been litigating (individuals, institutions, or member states) and which domestic courts have been referring questions to the CJEU. The significance of the judicial developments in this area are situated within the context of the domestic constitutional ramifications for member state legal orders thus revealing a neglected dimension in the constitutionalization debates, which traditionally emphasized the ramifications of internal EU law for the domestic constitutional order without expressly accommodating the constitutional significance of this external category of EU law nor the different challenges that this poses domestically.
2 Transformations, matrices and operators
Authors: Wong Chun Wa
Published: May 2013

Linear algebra of matrices is discussed in the context of rotations in space. Determinants are used to find solutions of simultaneous linear equations, to invert matrices and to find matrix eigenvalues. The linear wave equation quadratic in the infinitesimal generators of space and time translations is derived. Rotation operators and matrix groups are introduced.
5 Differential equations in physics
Authors: Wong Chun Wa
Published: May 2013

Ordinary and partial differential equations appear in physics as equations of motion or of state. They are often linear differential equations for which a sum of solutions remains a solution. The solution of first- and second-order linear differential equations are obtained. The specification of linearly independent solutions using suitable boundary/initial conditions is discussed. Special methods of solution using Green's functions, separation of variables and eigenfunction expansions are described.
5 Three common objections to Bayesian frameworks
Authors: Titelbaum Michael G.
Published: May 2013

This chapter shows how the Certainty-Loss Framework (CLF) and its interpretation developed in the previous two chapters offers new responses to traditional objections to Subjective Bayesianism. First, it explains exactly when a case counts as a counterexample to a formal modeling framework. Second, it applies CLF to Bas van Fraassen’s Judy Benjamin Problem and the more general problem of new theories, in which an agent comes to consider hypotheses she hadn’t entertained before. Third, the chapter takes up objections to the Ratio Formula relating conditional and unconditional degrees of belief (along the way explaining exactly what it is to assign a conditional degree of belief). Finally, the chapter assesses Bayesianism’s commitment to logical omniscience, the implausible rational requirement that agents be certain of all logical truths. The chapter explains how much logical omniscience CLF is committed to, and whether a little such commitment is necessarily a bad thing.
6 Generalized Conditionalization
Authors: Titelbaum Michael G.
Published: May 2013

This chapter explains how memory loss creates problems for Conditionalization, the traditional Bayesian norm for updating degrees of belief. It first presents stories in which agents suffer from memory loss (or the threat thereof) and shows how these stories are counterexamples to Conditionalization. It then argues that memory loss does indicate a failure of rationality on the part of the agent. The chapter then presents a new updating norm, Generalized Conditionalization (GC), which properly handles memory loss stories. GC is applied to a somewhat more complex story in which memory loss occurs multiple times, then the norm is used to derive a generalized version of Bas van Fraassen’s Reflection Principle applying to cases in which agents both gain and lose information.
8 The Proper Expansion Principle
Authors: Titelbaum Michael G.
Published: May 2013

This chapter examines the difficulties self-locating degrees of belief cause for traditional Bayesian modeling frameworks. It argues that these problems are caused not by Bayesianism’s view of the contents to which degrees of belief are assigned, but instead by the way Conditionalization (the traditional Bayesian updating norm) interacts with context-sensitive claims. Solving these problems requires us first to understand the interactions between formal models of the same story based on different modeling languages. A Proper Expansion Principle (PEP) is proposed that governs such interactions. Combining PEP with Generalized Conditionalization (an updating rule defended in previous chapters) yields the Certainty-Loss Framework (CLF), a formal framework that correctly models rational requirements in stories involving context-sensitivity. The version of PEP presented in this chapter improves on earlier versions proposed by the author, which were susceptible to a counterexample invented by Sarah Moss.
Embarrassment, Positive Moods, and Helping
Authors: Miller Christian
Published: May 2013

This chapter turns to two enhancers for helping – embarrassment and positive moods – and sees whether similar implications can be drawn as in the case of guilt. The first section distinguishes between embarrassment and shame, while the next two sections discuss what, for the moment, are the leading psychological models of the relationship between embarrassment and positive moods on the one hand, and helping on the other. Section four then turns to some of the consequences that these models seem to have.
Elevation, Activated Moral Norms, and Helping
Authors: Miller Christian
Published: May 2013

This chapter introduces two more enhancers, and follows a similar course as the previous two chapters. The one significant twist, though, is the kind of motivation to which these enhancers seem to give rise, which is moralistic and not egoistic. The first section of the chapter focuses on elevation, the second on activated moral norms, and the third on the implications for character.
Generalizing the Account
Authors: Miller Christian
Published: May 2013

This chapter begins by addressing a challenge to the proposal that comes from a rival psychological model of character and helping. Then section two sketches some of the aspects of the account of Mixed Helping Traits which can be carried over to thinking about our character traits in general. Section three examines a few important studies of non-moral traits which, if they had arrived at similar results for moral traits, would have supported the general framework that is being advanced here. Section four briefly reviews an important set of studies on specifically moral behavior which found results very much in line with the framework. Finally, section five develops some general principles for the experimental study of moral character which should seem plausible in light of the previous chapters.