bluuebunny/crossref_metadata_2025 huggingface dataset:
Ebstein’s Anomaly of the Tricuspid Valve in the Fetus – A Multicenter Experience
Authors: Gottschalk Ingo , Gottschalk Lea , Stressig Rüdiger , Ritgen Jochen , Herberg Ulrike , Breuer Johannes , Oberhoffer Renate , Willruth Arne , Strizek Brigitte , Geipel Annegret , Gembruch Ulrich , Berg Christoph
Published: June 2016

Purpose To assess the spectrum of associated anomalies, the intrauterine course, the outcome and possible prognostic markers in prenatally diagnosed Ebstein’s anomaly (EA).

Materials and Methods All cases of EA diagnosed over a period of 13 years with a minimum follow-up of 1 year were retrospectively collected in 4 tertiary referral centers in Germany.

Results In the study period 76 cases of EA were prenatally diagnosed. The mean gestational age at diagnosis was 25.0 weeks (range: 13 – 35). 41 (53.9 %) cases were isolated and 35 (46.1 %) had other cardiac and/or extracardiac anomalies. 19 (25.0 %) pregnant women opted for termination of pregnancy, intrauterine fetal death occurred in 7 cases (9.2 %), neonatal death in 14 cases (18.4 %), death in infancy or childhood in 9 cases (11.8 %) and 27 children (35.5 %) were alive at the last follow-up. After exclusion of terminations, the only parameter inversely correlated with intrauterine survival was hydrops fetalis. Prognostic parameters significantly associated with postnatal non-survival were an abnormal Celermajer index (right atrium/heart ratio > 0.7), cardiomegaly (cardiothoracic circumference ratio > 0.5), absence of antegrade flow over the pulmonary valve and earlier diagnosis in pregnancy.

Conclusion Prenatally diagnosed EA has a high morbidity and mortality with the highest loss rate in the intrauterine and neonatal period. In our study, hydrops fetalis was the only parameter significantly associated with intrauterine demise, while other prenatal markers were only significantly associated with postnatal mortality.
Exciton-polariton laser
Authors: Moskalenko S. A. , Tiginyanu I. M.
Published: June 2016

We present a review of the investigations realized in the last decades of the phenomenon of the Bose-Einstein condensation (BEC) in the system of two-dimensional cavity polaritons in semiconductor nanostructures. The conditions at which the excitons interacting with cavity photons form new type of quasiparticles named as polaritons are described. Since polaritons can form in a microcavity a weakly interacting Bose gas, similarly to the exciton gas in semiconductors, the microcavity exciton-polariton BEC emerged in the last decades as a new direction of the exciton BEC in solids, promising for practical applications. The high interest in BEC of exciton-polaritons in semiconductor microcavities is related to the ultra-low threshold lasing which has been demonstrated, in particular, for an electrically injected polariton laser based on bulk GaN microcavity diode working at room temperature.
Strain dynamics during La2O3/Lu2O3 superlattice and alloy formation
Authors: Proessdorf André , Niehle Michael , Grosse Frank , Rodenbach Peter , Hanke Michael , Trampert Achim
Published: June 2016

The dynamics of strain relaxation and intermixing during molecular beam epitaxy of La2O3 and Lu2O3 superlattices and alloys consisting of both binaries on Si(111) have been studied by real-time in situ grazing incidence x-ray diffraction and high resolution transmission electron microscopy. The presence of both hexagonal and cubic polymorphs of La2O3 influences the epitaxial formation within the superlattice. The process of strain relaxation is closely related to the presence of a (La,Lu)2O3 alloy adopting a cubic symmetry. It is formed by interdiffusion of La and Lu atoms reducing internal lattice mismatch within the superlattice. An interface thickness dominated by interdiffusion regions of about 3 monolayers is determined by high-angle annular dark field scanning transmission electron microscopy.
Holey-structured metamaterial lens for subwavelength resolution in ultrasonic characterization of metallic components
Authors: Amireddy Kiran Kumar , Balasubramaniam Krishnan , Rajagopal Prabhu
Published: June 2016

This paper presents the implementation of holey structured metamaterial lens for ultrasonic characterization of subwavelength subsurface defects in metallic components. Experimental results are presented, demonstrating ultrasound-based resolution of side drilled through-holes spaced (λ/5) in an aluminum block. Numerical simulation is then used to investigate the parameters that can help improve the resolution performance of the metamaterial lens, particularly, the addition of end-conditions. This work has important implications for higher resolution ultrasonic imaging in the context of practical non-destructive imaging and non-invasive material diagnostics.
Kinetic study of terahertz generation based on the interaction of two-color ultra-short laser pulses with molecular hydrogen gas
Authors: Soltani Gishini M. S. , Ganjovi A. , Saeed M.
Published: June 2016

In this work, using a two dimensional particle in cell-Monte Carlo collision simulation scheme, interaction of two-color ultra-short laser pulses with the molecular hydrogen gas (H2) is examined. The operational laser parameters, i.e., its pulse shape, duration, and waist, are changed and, their effects on the density and kinetic energy of generated electrons, THz electric field, intensity, and spectrum are studied. It is seen that the best pulse shape generating the THz signal radiation with the highest intensity is a trapezoidal pulse, and the intensity of generated THz radiation is increased at the higher pulse durations and waists. For all the operational laser parameters, the maximum value of emitted THz signal frequency always remains lower than 5 THz. The intensity of applied laser pulses is taken about 1014 w/cm2, and it is observed that while a small portion of the gaseous media gets ionized, the radiated THz signal is significant.
Quadratic formula for determining the drop size in pressure-atomized sprays with and without swirl
Authors: Lee T.-W , An Keju
Published: June 2016

We use a theoretical framework based on the integral form of the conservation equations, along with a heuristic model of the viscous dissipation, to find a closed-form solution to the liquid atomization problem. The energy balance for the spray renders to a quadratic formula for the drop size as a function, primarily of the liquid velocity. The Sauter mean diameter found using the quadratic formula shows good agreements and physical trends, when compared with experimental observations. This approach is shown to be applicable toward specifying initial drop size in computational fluid dynamics of spray flows.
Droplet migration in a Hele–Shaw cell: Effect of the lubrication film on the droplet dynamics
Authors: Ling Yue , Fullana Jose-Maria , Popinet Stéphane , Josserand Christophe
Published: June 2016

Droplet migration in a Hele–Shaw cell is a fundamental multiphase flow problem which is crucial for many microfluidics applications. We focus on the regime at low capillary number and three-dimensional direct numerical simulations are performed to investigate the problem. In order to reduce the computational cost, an adaptive mesh is employed and high mesh resolution is only used near the interface. Parametric studies are performed on the droplet horizontal radius and the capillary number. For droplets with an horizontal radius larger than half the channel height, the droplet overfills the channel and exhibits a pancake shape. A lubrication film is formed between the droplet and the wall and particular attention is paid to the effect of the lubrication film on the droplet velocity. The computed velocity of the pancake droplet is shown to be lower than the average inflow velocity, which is in agreement with experimental measurements. The numerical results show that both the strong shear induced by the lubrication film and the three-dimensional flow structure contribute to the low mobility of the droplet. In this low-migration-velocity scenario, the interfacial flow in the droplet reference frame moves toward the rear on the top and reverses direction moving to the front from the two side edges. The velocity of the pancake droplet and the thickness of the lubrication film are observed to decrease with capillary number. The droplet velocity and its dependence on capillary number cannot be captured by the classic Hele–Shaw equations, since the depth-averaged approximation neglects the effect of the lubrication film.
Reflection and extinction of light by self-assembled monolayers of a quinque-thiophene derivative: A coherent scattering approach
Authors: Gholamrezaie Fatemeh , de Leeuw Dago M. , Meskers Stefan C. J.
Published: June 2016

Scattering matrix theory is used to describe resonant optical properties of molecular monolayers. Three types of coupling are included: exciton-exciton, exciton-photon, and exciton-phonon coupling. We use the K-matrix formalism, developed originally to describe neutron scattering spectra in nuclear physics to compute the scattering of polaritons by phonons. This perturbation approach takes into account the three couplings and allows one to go beyond molecular exciton theory without the need of introducing additional boundary conditions for the polariton. We demonstrate that reflection, absorption, and extinction of light by 2D self-assembled monolayers of molecules containing quinque-thiophene chromophoric groups can be calculated. The extracted coherence length of the Frenkel exciton is discussed.
Double criticality and the two-way Boussinesq equation in stratified shallow water hydrodynamics
Authors: Bridges Thomas J. , Ratliff Daniel J.
Published: June 2016

Double criticality and its nonlinear implications are considered for stratified N–layer shallow water flows with N = 1,  2,  3. Double criticality arises when the linearization of the steady problem about a uniform flow has a double zero eigenvalue. We find that there are two types of double criticality: non-semisimple (one eigenvector and one generalized eigenvector) and semi-simple (two independent eigenvectors). Using a multiple scales argument, dictated by the type of singularity, it is shown that the weakly nonlinear problem near double criticality is governed by a two-way Boussinesq equation (non-semisimple case) and a coupled Korteweg-de Vries equation (semisimple case). Parameter values and reduced equations are constructed for the examples of two-layer and three-layer stratified shallow water hydrodynamics.
A scanning drift tube apparatus for spatiotemporal mapping of electron swarms
Authors: Korolov I. , Vass M. , Bastykova N. Kh. , Donkó Z.
Published: June 2016

A “scanning” drift tube apparatus, capable of mapping of the spatiotemporal evolution of electron swarms, developing between two plane electrodes under the effect of a homogeneous electric field, is presented. The electron swarms are initiated by photoelectron pulses and the temporal distributions of the electron flux are recorded while the electrode gap length (at a fixed electric field strength) is varied. Operation of the system is tested and verified with argon gas; the measured data are used for the evaluation of the electron bulk drift velocity. The experimental results for the space-time maps of the electron swarms — presented here for the first time — also allow clear observation of deviations from hydrodynamic transport. The swarm maps are also reproduced by particle simulations.
Electron beam moiré fringes imaging by image converter tube with a magnetic lens
Authors: Liao Yubo , Lei Yunfei , Cai Houzhi , Bai Yanli , Liu Jinyuan
Published: June 2016

An image converter tube with a magnetic lens was used to obtain static images of moiré fringes formed by electron beam. These moiré fringes are formed due to the interference between the anode mesh and the photocathode containing slits of various spatial frequencies. Moiré fringes are observed at an accelerating voltage of 3.5 kV requiring the magnetic excitation condition of ∼550 ampere-turns. Not only the features of the fringes are analyzed but also the change of fringe spacing as a function of the rotation angle is investigated. The experimental results are found well in agreement with the theoretical analysis. By changing the rotation angle or adjusting the excitation condition of the magnetic lens, we were able to record parallel moiré and secondary moiré fringes too. The secondary moiré fringes can be observed in the rotation angle range of −39.5° to −50.6°. The theoretical analysis indicates that the secondary moiré is formed by the interference between the photocathode slits and the 2-D periodic structure of the anode mesh. Combining our proposed moiré method with the pulse-dilation technique may potentially open the door for future applications, in various fields including, but not limited to, ultrafast electrical pulse diagnostics.
Fault tolerant filtering and fault detection for quantum systems driven by fields in single photon states
Authors: Gao Qing , Dong Daoyi , Petersen Ian R. , Rabitz Herschel
Published: June 2016

The purpose of this paper is to solve the fault tolerant filtering and fault detection problem for a class of open quantum systems driven by a continuous-mode bosonic input field in single photon states when the systems are subject to stochastic faults. Optimal estimates of both the system observables and the fault process are simultaneously calculated and characterized by a set of coupled recursive quantum stochastic differential equations.
A Trotter-Suzuki approximation for Lie groups with applications to Hamiltonian simulation
Authors: Somma Rolando D.
Published: June 2016

We present a product formula to approximate the exponential of a skew-Hermitian operator that is a sum of generators of a Lie algebra. The number of terms in the product depends on the structure factors. When the generators have large norm with respect to the dimension of the Lie algebra, or when the norm of the effective operator resulting from nested commutators is less than the product of the norms, the number of terms in the product is significantly less than that obtained from well-known results. We apply our results to construct product formulas useful for the quantum simulation of some continuous-variable and bosonic physical systems, including systems whose potential is not quadratic. For many of these systems, we show that the number of terms in the product can be sublinear or even subpolynomial in the dimension of the relevant local Hilbert spaces, where such a dimension is usually determined by the energy scale of the problem. Our results emphasize the power of quantum computers for the simulation of various quantum systems.
Shock-wave equation-of-state measurements in fused silica up to 1600 GPa
Authors: McCoy C. A. , Gregor M. C. , Polsin D. N. , Fratanduono D. E. , Celliers P. M. , Boehly T. R. , Meyerhofer D. D.
Published: June 2016

The properties of silica are important to geophysical and high-pressure equation-of-state research. Its most-prevalent crystalline form, α-quartz, has been extensively studied to TPa pressures. This article presents Hugoniot measurements on amorphous silica, commonly referred to as fused silica, over a range from 200 to 1600 GPa using laser-driven shocks and an α-quartz standard. These results extend the measured Hugoniot of fused silica to higher pressures. In the 200- to 600-GPa range, the data are in very good agreement with those obtained by Qi et al. [Phys. Plasmas 22, 062706 (2015)] using magnetically driven aluminum impactors and aluminum as a standard material. A new shock velocity/particle velocity relation is derived to fit the experimental data.
Single-site Lennard-Jones models via polynomial chaos surrogates of Monte Carlo molecular simulation
Authors: Kadoura Ahmad , Siripatana Adil , Sun Shuyu , Knio Omar , Hoteit Ibrahim
Published: June 2016

In this work, two Polynomial Chaos (PC) surrogates were generated to reproduce Monte Carlo (MC) molecular simulation results of the canonical (single-phase) and the NVT-Gibbs (two-phase) ensembles for a system of normalized structureless Lennard-Jones (LJ) particles. The main advantage of such surrogates, once generated, is the capability of accurately computing the needed thermodynamic quantities in a few seconds, thus efficiently replacing the computationally expensive MC molecular simulations. Benefiting from the tremendous computational time reduction, the PC surrogates were used to conduct large-scale optimization in order to propose single-site LJ models for several simple molecules. Experimental data, a set of supercritical isotherms, and part of the two-phase envelope, of several pure components were used for tuning the LJ parameters (ε, σ). Based on the conducted optimization, excellent fit was obtained for different noble gases (Ar, Kr, and Xe) and other small molecules (CH4, N2, and CO). On the other hand, due to the simplicity of the LJ model used, dramatic deviations between simulation and experimental data were observed, especially in the two-phase region, for more complex molecules such as CO2 and C2 H6.
Titratable macroions in multivalent electrolyte solutions: Strong coupling dressed ion approach
Authors: Adžić Nataša , Podgornik Rudolf
Published: June 2016

We present a theoretical description of the effect of polyvalent ions on the interaction between titratable macroions. The model system consists of two point-like macroions with dissociable sites, immersed in an asymmetric ionic mixture of monovalent and polyvalent salts. We formulate a dressed ion strong coupling theory, based on the decomposition of the asymmetric ionic mixture into a weakly electrostatically coupled monovalent salt and into polyvalent ions that are strongly electrostatically coupled to the titratable macro-ions. The charge of the macroions is not considered as fixed, but is allowed to respond to local bathing solution parameters (electrostatic potential, pH of the solution, and salt concentration) through a simple charge regulation model. The approach presented, yielding an effective polyvalent-ion mediated interaction between charge-regulated macroions at various solution conditions, describes the strong coupling equivalent of the Kirkwood-Schumaker interaction.
Comparison of three empirical force fields for phonon calculations in CdSe quantum dots
Authors: Kelley Anne Myers
Published: June 2016

Three empirical interatomic force fields are parametrized using structural, elastic, and phonon dispersion data for bulk CdSe and their predictions are then compared for the structures and phonons of CdSe quantum dots having average diameters of ˜2.8 and ˜5.2 nm (˜410 and ˜2630 atoms, respectively). The three force fields include one that contains only two-body interactions (Lennard-Jones plus Coulomb), a Tersoff-type force field that contains both two-body and three-body interactions but no Coulombic terms, and a Stillinger-Weber type force field that contains Coulombic interactions plus two-body and three-body terms. While all three force fields predict nearly identical peak frequencies for the strongly Raman-active “longitudinal optical” phonon in the quantum dots, the predictions for the width of the Raman peak, the peak frequency and width of the infrared absorption peak, and the degree of disorder in the structure are very different. The three force fields also give very different predictions for the variation in phonon frequency with radial position (core versus surface). The Stillinger-Weber plus Coulomb type force field gives the best overall agreement with available experimental data.
Evidence for a liquid-liquid critical point in supercooled water within the E3B3 model and a possible interpretation of the kink in the homogeneous nucleation line
Authors: Ni Yicun , Skinner J. L.
Published: June 2016

Supercooled water exhibits many thermodynamic anomalies, and several scenarios have been proposed to interpret them, among which the liquid-liquid critical point (LLCP) hypothesis is the most commonly discussed. We investigated Widom lines and the LLCP of deeply supercooled water, by using molecular dynamics simulation with a newly reparameterized water model that explicitly includes three-body interactions. Seven isobars are studied from ambient pressure to 2.5 kbar, and Widom lines are identified by calculating maxima in the coefficient of thermal expansion and the isothermal compressibility (both with respect to temperature). From these data we estimate that the LLCP of the new water model is at 180 K and 2.1 kbar. The oxygen radial distribution function is calculated along the 2 kbar isobar. It shows a steep change in the height of its second peak between 180 and 185 K, which indicates a transition between the high-density liquid and low-density liquid phases and which is consistent with the ascribed location of the critical point. The good agreement of the height of the second peak of the radial distribution function between simulation and experiment at 1 bar, as a function of temperature, supports the validity of the model. The location of the LLCP within the model is close to the kink in the experimental homogeneous nucleation line. We use existing experimental data to argue that the experimental LLCP is at 168 K and 1.95 kbar and speculate how this LLCP and its Widom line might be responsible for the kink in the homogeneous nucleation line.
The effects of control field detuning on the modulation instability in a three-level quantum well system
Authors: Borgohain Nitu , Konar S.
Published: June 2016

The paper presents a theoretical study of the modulation instability of a continuous or quasi-continuous optical probe in a three level quantum well system under electromagnetically induced transparency. The modulation instability is affected by the control field detuning, as well as even-order dispersion and by the strength of Kerr (third-order) and quintic (fifth-order) nonlinearities. The fourth-order dispersion reduces the bandwidth over which modulation instability occurs, whereas the quintic nonlinearity saturates the growth of the modulation instability. Detuning the control field from resonance can significantly reduce the growth of the modulation instability at both low and high power levels. At low powers, the system becomes stable against modulation instability for small detuning of the control field and at high powers modulation instability disappears for larger detuning.
Influence of Joule heating on current-induced domain wall depinning
Authors: Moretti Simone , Raposo Victor , Martinez Eduardo
Published: June 2016

The domain wall depinning from a notch in a Permalloy nanostrip on top of a SiO2/Si substrate is studied theoretically under application of static magnetic fields and the injection of short current pulses. The influence of Joule heating on current-induced domain wall depinning is explored self-consistently by coupling the magnetization dynamics in the ferromagnetic strip to the heat transport throughout the system. Our results indicate that Joule heating plays a remarkable role in these processes, resulting in a reduction in the critical depinning field and/or in a temporary destruction of the ferromagnetic order for typically injected current pulses. In agreement with experimental observations, similar pinning-depinning phase diagrams can be deduced for both current polarities when the Joule heating is taken into account. These observations, which are incompatible with the sole contribution of spin transfer torques, provide a deeper understanding of the physics underlying these processes and establish the real scope of the spin transfer torque. They are also relevant for technological applications based on current-induced domain-wall motion along soft strips.
Predicting the future trend of popularity by network diffusion
Authors: Zeng An , Yeung Chi Ho
Published: June 2016

Conventional approaches to predict the future popularity of products are mainly based on extrapolation of their current popularity, which overlooks the hidden microscopic information under the macroscopic trend. Here, we study diffusion processes on consumer-product and citation networks to exploit the hidden microscopic information and connect consumers to their potential purchase, publications to their potential citers to obtain a prediction for future item popularity. By using the data obtained from the largest online retailers including Netflix and Amazon as well as the American Physical Society citation networks, we found that our method outperforms the accurate short-term extrapolation and identifies the potentially popular items long before they become prominent.
Gate-tunable rectification inversion and photovoltaic detection in graphene/WSe2 heterostructures
Authors: Gao Anyuan , Liu Erfu , Long Mingsheng , Zhou Wei , Wang Yiyan , Xia Tianlong , Hu Weida , Wang Baigeng , Miao Feng
Published: June 2016

We studied electrical transport properties including gate-tunable rectification inversion and polarity inversion, in atomically thin graphene/WSe2 heterojunctions. Such engrossing characteristics are attributed to the gate tunable mismatch of Fermi levels of graphene and WSe2. Also, such atomically thin heterostructure shows excellent performances on photodetection. The responsivity of 66.2 mA W−1 (without bias voltage) and 350 A W−1 (with 1 V bias voltage) can be reached. What is more, the devices show great external quantum efficiency of 800%, high detectivity of 1013 cm Hz1/2/W, and fast response time of 30 μs. Our study reveals that vertical stacking of 2D materials has great potential for multifunctional electronic and optoelectronic device applications in the future.
Quantification of size effects in the magnetoelectric response of metallic glass/PVDF laminates
Authors: Lasheras A. , Gutiérrez J. , Barandiarán J. M.
Published: June 2016

Metallic glass/polyvinylidene fluoride three-layered magnetoelectric laminated composites have been studied. Size effects in the magnetoelectric response arisen both from the reduction of the length of the laminate and from the increase of the operating frequency have been quantified for the lengths ranging from 3 cm down to 0.5 cm. It has been concluded that the decrease in this magnetoelectric response arises mainly from the demagnetizing effects, with reductions of 86% for the longest laminate that increase up to 99% for the shortest one. From these values, an intrinsic magnetoelectric coefficient of 325 V/cm Oe has been obtained.
Jumping liquid metal droplet in electrolyte triggered by solid metal particles
Authors: Tang Jianbo , Wang Junjie , Liu Jing , Zhou Yuan
Published: June 2016

We report the electron discharge effect due to point contact between liquid metal and solid metal particles in electrolyte. Adding nickel particles induces drastic hydrogen generating and intermittent jumping of a sub-millimeter EGaIn droplet in NaOH solution. Observations from different orientations disclose that such jumping behavior is triggered by pressurized bubbles under the assistance of interfacial interactions. Hydrogen evolution around particles provides clear evidence that such electric instability originates from the varied electric potential and morphology between the two metallic materials. The point-contact-induced charge concentration significantly enhances the near-surface electric field intensity at the particle tips and thus causes electric breakdown of the electrolyte.
Inversion of absorption anisotropy and bowing of crystal field splitting in wurtzite MgZnO
Authors: Neumann M. D. , Esser N. , Chauveau J.-M. , Goldhahn R. , Feneberg M.
Published: June 2016

The anisotropic optical properties of wurtzite MgxZn1−xO thin films (0≤x≤0.45) grown on m-plane ZnO substrates by plasma assisted molecular beam epitaxy are studied using spectroscopic ellipsometry at room temperature. The data analysis provides the dielectric functions for electric field polarizations perpendicular and parallel to the optical axis. The splitting between the absorption edges of the two polarization directions decreases between x = 0 and x = 0.24, while an inverted absorption anisotropy is found at higher Mg content, indicating a sign change of the crystal field splitting Δcr as for the spin orbit parameter. The characteristic energies such as exciton binding energies and band gaps are determined from the analysis of the imaginary parts of the dielectric functions. In particular, these data reveal a bowing parameter of b=−283 meV for describing the compositional dependence of the crystal field splitting and indicate Δcr=−327 meV for wurtzite MgO. The inverted valence band ordering of ZnO (Γ7-Γ9-Γ7) is found to be preserved with increasing Mg content, while the optical selection rules interchange.
Improved thermal stability of N-doped Sb materials for high-speed phase change memory application
Authors: Hu Yifeng , Zhu Xiaoqin , Zou Hua , Zhang Jianhao , Yuan Li , Xue Jianzhong , Sui Yongxing , Wu Weihua , Song Sannian , Song Zhitang
Published: June 2016

Compared with pure Sb, N-doped Sb material was proved to be a promising candidate for the phase change memory (PCM) use because of its higher crystallization temperature (∼250 °C), larger crystallization activation energy (3.53 eV), and better data retention ability (166 °C for 10 years). N-doping also broadened the band gap and refined grain size. The reversible resistance transition could be achieved by an electric pulse as short as 8 ns for the PCM cell based on N-doped Sb material. A lower operation power consumption (the energy for RESET operation 2.2 × 10−12 J) was obtained. In addition, N-doped Sb material showed a good endurance of 1.8 × 105 cycles.
On-chip near-infrared spectroscopy of CO2 using high resolution plasmonic filter array
Authors: Chong Xinyuan , Li Erwen , Squire Kenneth , Wang Alan X.
Published: June 2016

We report an ultra-compact, cost-effective on-chip near-infrared spectroscopy system for CO2 sensing using narrow-band optical filter array based on plasmonic gratings with a waveguide layer. By varying the periodicity of the gratings, the transmission spectra of the filters can be continuously tuned to cover the 2.0 μm sensing window with high spectral resolution around 10 nm. Our experimental results show that the on-chip spectroscopy system can resolve the two symmetric vibrational bands of CO2 at 2.0 μm wavelength, which proves its potential to replace the expensive commercial IR spectroscopy system for on-site gas sensing.
Luminescence evolution from alumina ceramic surface before flashover under direct and alternating current voltage in vacuum
Authors: Su Guo-Qiang , Wang Yi-Bo , Song Bai-Peng , Mu Hai-Bao , Zhang Guan-Jun , Li Feng , Wang Meng
Published: June 2016

The luminescence evolution phenomena from alumina ceramic surface in vacuum under high voltage of direct and alternating current are reported, with the voltage covering a large range from far below to close to the flashover voltage. Its time resolved and spatial distributed behaviors are examined by a photon counting system and an electron-multiplying charge-coupled device (EMCCD) together with a digital camera, respectively. The luminescence before flashover exhibits two stages as voltage increasing, i.e., under a relative low voltage (Stage A), the luminescence is ascribed to radiative recombination of hetero-charges injected into the sample surface layer by Schottky effect; under a higher voltage (Stage B), a stable secondary electron emission process, resulting from the Fowler-Nordheim emission at the cathode triple junction (CTJ), is responsible for the luminescence. Spectrum analysis implies that inner secondary electrons within the surface layer of alumina generated during the SSEE process also participate in the luminescence of Stage B. A comprehensive interpretation of the flashover process is formulated, which might promote a better understanding of flashover issue in vacuum.
Resonance coupling in plasmonic nanomatryoshka homo- and heterodimers
Authors: Ahmadivand Arash , Sinha Raju , Pala Nezih
Published: June 2016

Here, we examine the electromagnetic (EM) energy coupling and hybridization of plasmon resonances between closely spaced concentric nanoshells known as “nanomatryoshka” (NM) units in symmetric and antisymmetric compositions using the Finite Difference Time Domain (FDTD) analysis. Utilizing plasmon hybridization model, we calculated the energy level diagrams and verified that, in the symmetric dimer (in-phase mode in a homodimer), plasmonic bonding modes are dominant and tunable within the considered bandwidth. In contrast, in the antisymmetric dimer (out-of-phase mode in a heterodimer), due to the lack of the geometrical symmetry, new antibonding modes appear in the extinction profile, and this condition gives rise to repeal of dipolar field coupling. We also studied the extinction spectra and positions of the antibonding and bonding modes excited due to the energy coupling between silver and gold NM units in a heterodimer structure. Our analysis suggest abnormal shifts in the higher energy modes. We propose a method to analyze the behavior of multilayer concentric nanoshell particles in an antisymmetric orientation employing full dielectric function calculations and the Drude model based on interband transitions in metallic components. This study provides a method to predict the behavior of the higher energy plasmon resonant modes in entirely antisymmetric structures such as compositional heterodimers.
Scoping of models to support population-based regional health planning and management: comparison with the regional operating model in Victoria, Australia
Authors: Levesque Jean-Frederic , O'Dowd John J. M. , Ní Shé Éidín M. , Weenink Jan-Willem , Gunn Jane
Published: June 2016

Objective The aim of the present study was to try to understand the breadth and comprehensiveness of a regional operating model (ROM) developed within the Victorian Department of Health’s North West Metropolitan Region office in Melbourne, Australia. Methods A published literature search was conducted, with additional website scanning, snowballing technique and expert consultation, to identify existing operating models. An analytical grid was developed covering 16 components to evaluate the models and assess the exhaustiveness of the ROM. Results From the 34 documents scoped, 10 models were identified to act as a direct comparator to the ROM. These concerned models from Australia (n = 5) and other comparable countries (Canada, UK). The ROM was among the most exhaustive models, covering 13 of 16 components. It was one of the few models that included intersectoral actions and levers of influence. However, some models identified more precisely the planning tools, prioritisation criteria and steps, and the allocation mechanisms. Conclusions The review finds that the ROM appears to provide a wide coverage of aspects of planning and integrates into a single model some of the distinctive elements of the other models scoped. What is known about the topic? Various jurisdictions are moving towards a population-based approach to manage public services with regard to the provision of individual medical and social care. Various models have been proposed to guide the planning of services from a population health perspective. What does this paper add? This paper assesses the coverage of attributes of operating models supporting a population health planning approach to the management of services at the regional or local level. It provides a scoping of current models proposed to organise activities to ensure an integrated approach to the provision of services and compares the scoped models to a model recently implemented in Victoria, Australia. What are the implications for practitioners? This paper highlights the relative paucity of operating models describing in concrete terms how to manage medical and social services from a population perspective and encourages organisations that are accountable for securing population health to clearly articulate their own operating model. It outlines strengths and potential gaps in current models.
Effect of the 4-h target on time-to-analgesia in an Australian emergency department: a pilot retrospective observational study
Authors: Hughes James A. , Cabilan C. J. , Staib Andrew
Published: June 2016

Objectives The aim of the present study was to assess the relationship between and the effect of the 4-h target or National Emergency Access Target (NEAT) on the time-to-analgesia (TTA), as well as the provision of analgesia in an adult emergency department (ED). Methods The present study was a pilot descriptive explorative retrospective cohort study conducted in a public metropolitan ED. Eligible presentations for analysis were adults presenting with a documented pain score of ≥4 out of 10 between 1 and 14 September 2014. Triage Category 1, pregnant, chest pain and major trauma cases were excluded from the study. As a result, data for 260 patients were analysed. Results Of 260 patients, 176 had analgesia with a median TTA of 49 min. Increased NEAT compliance did not significantly decrease TTA. However, when the factors that affected the provision of analgesia were analysed, an association was demonstrated between Admitted and Short Stay NEAT performance and the provision of analgesia. The likelihood of receiving analgesia at all increased as Admitted and Short Stay NEAT compliance improved. Conclusion NEAT is a significant health policy initiative with little clinical evidence supporting its implementation. However, as the Admitted NEAT compliance increases, the probability of receiving analgesia increases, demonstrating a possible link between hospital function and clinical care provision that needs to be explored further. What is known about the topic? The 4-h target or NEAT is a widely used initiative in EDs to allay crowding and access block. However, little is known of its impact on clinical endpoints, such as TTA. What does this paper add? TTA was not significantly reduced as NEAT compliance increased. However, when the focus was on the probability of receiving analgesia, the results demonstrated that an improvement in Admitted and Short Stay NEAT compliance was associated with an increase in the likelihood of patients receiving analgesia. What are the implications for practitioners? NEAT is a relatively recent initiative, hence evidence of its effect on clinically orientated outcomes is limited. Nevertheless, evidence of safety and effectiveness is emerging. The results of the present pilot study provide preliminary data on the timeliness of patient-centred care as demonstrated by TTA and administration of analgesia when required. Further, the results would seem to suggest that the provision of analgesia is affected by how timely patients are moved out of the ED to the in-patient setting. As for future investigations on TTA as a result of NEAT, a wider time period should be considered so that the accurate effect of compliance thresholds (e.g. ≥90%, 81–89%, ≤80%) of NEAT can be explored.
Thermal and physicochemical properties of red tilapia (Oreochromis niloticus) surimi gel as affected by microbial transglutaminase
Authors: Seighalani Fariba Zad Bagher , Bakar Jamilah , Saari Nazamid , Khoddami Ali
Published: June 2016

Thermal and physicochemical properties of red tilapia (Oreochromis niloticus) surimi gel incorporated with different levels of microbial transglutaminase (MTGase) were investigated. Surimi samples mixed with various concentrations of MTGase were subjected to two-stages heating (at 45°C followed by 90°C) to prepare surimi gel. Samples formulated with 0.30 MTGase (units/g surimi) showed the highest breaking force and deformation, and lowest expressible water content among treatments. Highest storage modulus was found in the gels mixed with 0.30 MTGase (units/g surimi). Compared with control surimi gel, addition of microbial transglutaminase to levels 0.10, 0.20 and 0.30 (units/g surimi) increased the enthalpy and maximum transition temperature of myosin. Results suggest that up to 0.30 MTGase (units/g surimi) could improve texture, colour, water-holding capacity, elasticity and thermal stability of red tilapia surimi gel.
Prevalence of and disparities in HIV-related sexual risk behaviours among Chinese youth in relation to sexual orientation: a cross-sectional study
Authors: Guo Chao , Zhang Lei , Wang Zhenjie , Chen Gong , Zheng Xiaoying
Published: June 2016

Background
The aim of this study was to calculate the prevalence rate of HIV-related sexual risk behaviours (HSRB) among Chinese youth and determine whether there was an association between sexual orientation and HSRB. Methods: This study used a nationally representative survey of youth aged 15–24 years in China. Population numbers, prevalence, and proportions were calculated where appropriate. χ2 tests were used to determine the difference within categorical variables. Multivariate logistic regression was used to calculate the adjusted odd ratios (AOR) and 95% confidence interval (CI). Results: The rate of any HSRB among sexually active youth was 79.43%, and the most common HSRB was lack of condom use during the first sexual experience (66.02%). After adjusting for demographic and socioeconomic variables (sex, age, residence, living with parents or not, father’s education and annual family income), non-heterosexual orientation was found to significantly increase the odds of HSRB (AOR = 2.42, 95% CI: 1.16–5.05). Conclusions: Non-heterosexual youth are at a higher risk of partaking in HSRB. The high prevalence of HSRB indicates the insufficiency of sex education for Chinese youth, especially for non-heterosexual youth. Greater efforts should be made to increase reproductive and sexual health services for Chinese youth.
Indicators of HIV-risk resilience among men who have sex with men: a content analysis of online profiles
Authors: White Hughto Jaclyn M. , Hidalgo Anna P. , Bazzi Angela R. , Reisner Sari L. , Mimiaga Matthew J.
Published: June 2016

Background: HIV-risk resilience, or positive adaptation in the face of risk, is increasingly being recognised as an important characteristic among men who have sex with men (MSM). However, resilience in the context of online partner seeking remains underexplored among MSM. Methods: Using content analysis methodology, this study operationalised indicators of HIV-risk resilience in the profiles of 933 MSM using a sexual networking website. HIV-risk resilience included endorsing foreplay only (non-penetrative sex) or a versatile sexual position; being “out” (e.g. disclosed sexual orientation), having a profile photo, seeking friendship, seeking a relationship, serosorting, not endorsing alcohol or drug use, safer sexual adventurism (e.g. role playing, bondage), and safer sex. Results: The majority of men were between 18 and 35 years old (76.0%) and 73.3% were racial/ethnic minorities. The mean number of resilience components endorsed was 5.2 (s.d. = 1.5; range 0–9). Nearly half (48.0%) reported being “out” and 68.7% had a profile photo. The majority of men were seeking relationships (66.5%) and/or friendships (69.7%), were sexually versatile (53.3%), and preferred safer sex only (76.3%). The majority did not endorse drug use (82.0%) and 25.4% did not endorse alcohol use. Nearly one-quarter (21.4%) endorsed sexual adventurism and 2.5% were serosorting by partner’s HIV negative status. Conclusion: HIV-risk resilience may be common among MSM using sexual networking websites and may manifest in safer sex intentions. Rather than exclusively focusing on sexual risk reduction, health promotion efforts targeting MSM online should acknowledge, measure, and leverage existent HIV-risk resilience strategies in this group.
Projecting wildfire area burned in the south-eastern United States, 2011–60
Authors: Prestemon Jeffrey P. , Shankar Uma , Xiu Aijun , Talgo K. , Yang D. , Dixon Ernest , McKenzie Donald , Abt Karen L.
Published: June 2016

Future changes in society and climate are expected to affect wildfire activity in the south-eastern United States. The objective of this research was to understand how changes in both climate and society may affect wildfire in the coming decades. We estimated a three-stage statistical model of wildfire area burned by ecoregion province for lightning and human causes (1992–2010) based on precipitation, temperature, potential evapotranspiration, forest land use, human population and personal income. Estimated parameters from the statistical models were used to project wildfire area burned from 2011 to 2060 under nine climate realisations, using a combination of three Intergovernmental Panel on Climate Change-based emissions scenarios (A1B, A2, B2) and three general circulation models. Monte Carlo simulation quantifies ranges in projected area burned by county by year, and in total for higher-level spatial aggregations. Projections indicated, overall in the Southeast, that median annual area burned by lightning-ignited wildfire increases by 34%, human-ignited wildfire decreases by 6%, and total wildfire increases by 4% by 2056–60 compared with 2016–20. Total wildfire changes vary widely by state (–47 to +30%) and ecoregion province (–73 to +79%). Our analyses could be used to generate projections of wildfire-generated air pollutant exposures, relevant to meeting the National Ambient Air Quality Standards.
Microstructure and multifunctional properties of Ti–Si–B–C coatings by plasma-enhanced chemical vapour deposition
Authors: Shin J. H. , Lim W. J. , Kim K. H.
Published: June 2016

Hard coatings are required to have a long lifetime without performance degradation when used in tough working environments. In this study, quaternary Ti–Si–B–C coatings with various Si contents were synthesised at a relatively low temperature of 600°C by a plasma-enhanced chemical vapour deposition. Effect of the Si/(Si+B) ratio on the microstructure and mechanical properties of the Ti–Si–B–C coatings was systematically investigated. Instrumental analyses, such as EPMA, XRD, XPS and HR-TEM, revealed that the microstructure was changed from a huge crystalline structure with an hexagonal close-packed (HCP) (Ti,C)B2 phase into a nanocomposite structure that consists of nano-sized HCP (Ti,C)B2 crystallites and amorphous SiC/TiC phases by a percolation effect with the Si addition. As the Si content increased, hardness of the Ti–Si–B–C coatings varied from 18.8 to 35.6 GPa. In addition, the tribology and anti-oxidation properties of the Ti–Si–B–C coatings with the characteristic microstructural evolution were fairy improved compared with Ti–B–C coatings. The Ti–Si–B–C coatings had excellent multifunctional properties, including high hardness, low friction coefficient and high temperature oxidation resistance.
Applying Portfolio Management to Implement Ecosystem-Based Fishery Management (EBFM)
Authors: Di Jin  , DePiper Geret , Hoagland Porter
Published: June 2016

Portfolio management has been suggested as a tool to help implement ecosystem-based fisheries management. The portfolio approach involves the application of financial portfolio theory to multispecies fishery management to account for species interdependencies, uncertainty, and sustainability constraints. By considering covariance among species, this approach allows economic risks and returns to be calculated across varying combinations of stock sizes. Trade-offs between expected aggregate returns and portfolio risk can thus be assessed. We develop a procedure for constructing portfolio models to help implement ecosystem-based fisheries management in the northeastern United States, using harvest data from the National Marine Fisheries Service. Extending the work of Sanchirico et al. (2008), we propose a measure of excessive risk taking, which may be used by managers to monitor signals of nonoptimal harvests. In addition, we conduct portfolio assessments of historical commercial fishing performance at different accounting stances: the large marine ecosystem, the New England region, and the community (fishing ports). We show that portfolio analysis could inform management at each level. Results of the study suggest that excessive risk taking is associated with overfishing, and risk management is therefore important for ensuring sustainability.

Received June 28, 2015; accepted January 14, 2016 Published online June 1, 2016