bluuebunny/crossref_metadata_2025 huggingface dataset:
Reflection and Transmission of Acoustic Waves through the Layer of Multifractional Bubbly Liquid
Authors: Gubaidullin Damir Anvarovich , Gafiyatov Ramil Nakipovich
Published: February 2018

The mathematical model that determines reflection and transmission of acoustic wave through a medium containing multifractioanl bubbly liquid is presented. For the water-water with bubbles-water model the wave reflection and transmission coefficients are calculated. The influence of the bubble layer thickness on the investigated coefficients is shown. The theory compared with the experiment. It is shown that the theoretical results describe and explain well the available experimental data. It is revealed that the special dispersion and dissipative properties of the layer of bubbly liquid can significantly influence on the reflection and transmission of acoustic waves in multilayer medium
Tree root detection from ground surface vibration measurements
Authors: Kalkowski Michał K. , Muggleton Jennifer M , Rustighi Emiliano
Published: February 2018

Rapid development of urban infrastructure in past decades together with a relatively recent growth of awareness of its impact on the natural environment result in an increased interest in non-destructive ground interrogation methods. Tree root damage is a very well known issue in civil engineering and can emerge as road surface fracture, building foundations disintegration or pipe penetration, among others. In this paper we investigate the feasibility of using a vibroacoustic method for tree root mapping. The core of the idea is that the mechanical waves induced by an excitation mechanism acting on the tree trunk propagate to the roots and then radiate into the surrounding soil. Owing to that, the response measured at the ground surface contains the contribution of waves radiating from roots and can be used for mapping their extent. In this paper, we report a set of field experiments on a ‘purpose-built’ root-trunk model buried underground. These preliminary results both demonstrate the technique and shed light on related challenges and limitations.
Interaction acoustic waves with a layered structure containing layer of bubbly liquid
Authors: Gubaidullin Damir , Nikiforov Anatolii
Published: February 2018

The results of a theoretical study of the effect of a bubble layer on the propagation of acoustic waves through a thin three-layered barrier at various angles of incidence are presented. The barrier consists of a layer of gel with polydisperse air bubbles bounded by layers of polycarbonate. It is shown that the presence of polydisperse air bubbles in the gel layer significantly changes the transmission and reflection of the acoustic signal when it interacts with such an obstacle for frequencies close to the resonant frequency of natural oscillations of the bubbles. The frequency range is identified where the angle of incidence has little effect on the reflection and transmission coefficients of acoustic waves.
Monitoring of drilling conditions using the Hilbert-Huang transformation
Authors: Wolszczak Piotr , Litak Grzegorz , Dziuba Marek
Published: February 2018

The article presents the results of design and monitoring the drilling process. Vibroacoustic sensors were used to observe spindle vibrations. These signals were subjected to a Huang decomposition and a Fourier transform. Results for various conditions were studied and classified with help of Fourier spectra and the envelope curves. Using the additional results of numerical simulations sources of vibration were identified. We considered four different types of drilling which were diversified in terms of geometrical parameters of blades. The application of Hilbert transform enable to find nonlinear characteristics via the deflection profile of resonance backbone curves.
Calibrated FEM modelling of rock cutting with PDC cutter
Authors: Yari Nina , Kapitaniak Marcin , Vaziri Vahid , Ma Lifeng , Wiercigroch Marian
Published: February 2018

Complexity of bit-rock interactions and formation fracture makes rock drilling a challenging task from modelling perspective. A finite element model is developed which can plausibly capture the rock fractures while it is capable of evaluating drilling forces for various values of Rate of Penetration (ROP), bit angular velocity and cutter configuration. Firstly, experiments on a single cutter rig are performed with various drilling parameters to be compared to the proposed FE model. Prior to detailed numerical simulation, a rigorous computation test on material model characterization and the element size and type is conducted to ensure feasible and reliable simulation results. The cutting forces are analysed for different values of WOB, rake angle, initial depth of cut and cutter speed for a single-cutter linear cutting. The formation fragmentation process and computed results are comparable to laboratory tests.
Dynamic Analysis of a Drillstring-Riser System Drilling in Deep Water
Authors: Liao Maolin , Zhou Yingcao , Su Yinao , Lian Zhilong , Jiang Hongwei
Published: February 2018

A mathematical model of a drillstring-riser system is developed to analyze the system dynamics when drilling in deep water. For the proposed model, a riser and a drillstring are combined as a pipe-in-pipe structure, along which the interactions between the riser and the drillstring are introduced by a series of spring-friction units. Numerical simulations of the developed mathematical model are carried out by Abaqus in which the finite element method is adopted. Comparing with the riser deflection calculated by previously published models which exclude the influences of the drillstring-riser interactions, the maximal riser deflection obtained by using the proposed drillstring-riser system is relatively small. Namely, the drillstring-riser interactions restrict the riser deflection. This finding indicates that, in a given safety margin of the riser deflection, the drillstring-riser system has stronger capacity of anti-deflection. Additionally, the influence of sea depth is investigated; the dynamic response of a drillstring-riser system drilling in deep water is obviously different from the corresponding condition drilling in shallow water. In order to maintain the drillstring-riser system work in a safe condition, the operations, such as thickening the riser wall, enhancing the control of the top drift, removing a part of buoyancy modules, decreasing WOB, and increasing the top tension of the riser, are suggested to be applied.
Woran Therapeuten erkranken
Authors: Kampitsch Natalie , Zaglauer Jacqueline , Dürsch Jessica , Lukas Katharina , Plattner Annalena
Published: February 2018

Eine Projektarbeit an der VPT-Berufsfachschule Bad Birnbach ermittelte häufige Erkrankungen von Physiotherapeuten und Masseuren sowie deren
Zusammenhang mit Arbeitsbelastung, Geschlecht und eigener Einschätzung des Allgemeinzustands. Das VPTMAGAZIN stellt die Ergebnisse der
Befragung auszugsweise vor.
Ergotherapie bei Pronator-teres-Syndrom – Nerv in Not
Authors: Schwarzl Stefanie , Toriser Romana
Published: February 2018

Nervenkompressionen an der oberen Extremität werden vorwiegend operativ behandelt. Dass eine konservative Therapie bei Medianuskompressionen jedoch nicht nur indiziert, sondern auch erfolgversprechend sein kann, das zeigen die Ergotherapeutinnen Stefanie Schwarzl und Romana Toriser.
Ergotherapie bei Rhizarthrose – Wenn der Daumen Ärger macht
Authors: Zander Andrea
Published: February 2018

Der Daumen ist unser stärkster Finger und nahezu immer beim Greifen beteiligt. Eine Daumensattelgelenksarthrose beeinträchtigt entsprechend den Alltag. Andrea Zander zeigt effiziente Therapieansätze.
A broadband variable-temperature test system for complex permittivity measurements of solid and powder materials
Authors: Zhang Yunpeng , Li En , Zhang Jing , Yu Chengyong , Zheng Hu , Guo Gaofeng
Published: February 2018

A microwave test system to measure the complex permittivity of solid and powder materials as a function of temperature has been developed. The system is based on a TM0n0 multi-mode cylindrical cavity with a slotting structure, which provides purer test modes compared to a traditional cavity. To ensure the safety, effectiveness, and longevity, heating and testing are carried out separately and the sample can move between two functional areas through an Alundum tube. Induction heating and a pneumatic platform are employed to, respectively, shorten the heating and cooling time of the sample. The single trigger function of the vector network analyzer is added to test software to suppress the drift of the resonance peak during testing. Complex permittivity is calculated by the rigorous field theoretical solution considering multilayer media loading. The variation of the cavity equivalent radius caused by the sample insertion holes is discussed in detail, and its influence to the test result is analyzed. The calibration method for the complex permittivity of the Alundum tube and quartz vial (for loading powder sample), which vary with the temperature, is given. The feasibility of the system has been verified by measuring different samples in a wide range of relative permittivity and loss tangent, and variable-temperature test results of fused quartz and SiO2 powder up to 1500 °C are compared with published data. The results indicate that the presented system is reliable and accurate. The stability of the system is verified by repeated and long-term tests, and error analysis is presented to estimate the error incurred due to the uncertainties in different error sources.
Response to “Comment on ‘Solitonic and chaotic behaviors for the nonlinear dust-acoustic waves in a magnetized dusty plasma’” [Phys. Plasmas 24, 094701 (2017)]
Authors: Zhen Hui-Ling , Tian Bo , Xie Xi-Yang , Wu Xiao-Yu , Wen Xiao-Yong
Published: February 2018

On our previous construction [H. L. Zhen et al., Phys. Plasmas 23, 052301 (2016)] of the soliton solutions of a model describing the dynamics of the dust particles in a weakly ionized, collisional dusty plasma comprised of the negatively charged cold dust particles, hot ions, hot electrons, and stationary neutrals in the presence of an external static magnetic field, Ali et al. [Phys. Plasmas 24, 094701 (2017)] have commented that there exists a different form of Eq. (4) from that shown in Zhen et al. [Phys. Plasmas 23, 052301 (2016)] and that certain interesting phenomena with the dust neutral collision frequency ν0>0 are ignored in Zhen et al. [Phys. Plasmas 23, 052301 (2016)]. In this Reply, according to the transformation given by the Ali et al. [Phys. Plasmas 24, 094701 (2017)] comment, we present some one-, two-, and N-soliton solutions which have not been obtained in the Ali et al. [Phys. Plasmas 24, 094701 (2017)] comment. We point out that our previous solutions in Zhen et al. [Phys. Plasmas 23, 052301 (2016)] are still valid because of the similarity between the two dispersion relations of previous solutions in Zhen et al. [Phys. Plasmas 23, 052301 (2016)] and the solutions presented in this Reply. Based on our soliton solutions in this Reply, it is found that the soliton amplitude is inversely related to Zd and B0, but positively related to md and α, where α refers to the coefficient of the nonlinear term, Zd and md are the charge number and mass of a dust particle, respectively, B0 represents the strength of the external static magnetic field. We also find that the two solitons are always in parallel during the propagation.
Dynamics and control of the vortex flow behind a slender conical forebody by a pair of plasma actuators
Authors: Meng Xuanshi , Long Yuexiao , Wang Jianlei , Liu Feng , Luo Shijun
Published: February 2018

Detailed particle-image-velocimetry (PIV) and surface pressure measurements are presented to study the vortex flow behind a slender conical forebody at high angles of attack. The results confirm the existence of two randomly appearing mirror imaged asymmetric bi-stable states of the separation vortices, giving rise to large side force and moment. A pair of carefully designed dielectric barrier discharge plasma actuators mounted near the apex and on both sides of the conical body are used to manipulate the vortex flow and thus provide control of the side forces on the body without using flaps. By making use of a duty-cycle actuation scheme that alternately actuates the port and starboard plasma actuators and optimizing the duty-cycle frequency, the present work demonstrates the feasibility of achieving a nearly perfect linear proportional control of the side force and moment in response to the duty-cycle ratio. Phase-locked PIV and surface pressure measurements are used to study the unsteady dynamic evolution of the flow within one duty-cycle actuation to reveal the flow control mechanism. It is found that under the duty-cycle actuation with the optimized frequency, the vortex flow essentially follows the plasma actuation by alternating between the two bi-stable states controlled directly by the duty-cycle ratio.
A Peltier-based freeze-thaw device for meteorite disaggregation
Authors: Ogliore R. C.
Published: February 2018

A Peltier-based freeze-thaw device for the disaggregation of meteorite or other rock samples is described. Meteorite samples are kept in six water-filled cavities inside a thin-walled Al block. This block is held between two Peltier coolers that are automatically cycled between cooling and warming. One cycle takes approximately 20 min. The device can run unattended for months, allowing for ∼10 000 freeze-thaw cycles that will disaggregate meteorites even with relatively low porosity. This device was used to disaggregate ordinary and carbonaceous chondrite regoltih breccia meteorites to search for micrometeoroid impact craters.
Propagation of transition fronts in nonlinear chains with non-degenerate on-site potentials
Authors: Shiroky I. B. , Gendelman O. V.
Published: February 2018

We address the problem of transition front propagation in chains with a bi-stable nondegenerate on-site potential and a nonlinear gradient coupling. For generic nonlinear coupling, one encounters a special regime of transitions, characterized by extremely narrow fronts, far supersonic velocities of the front propagation, and long waves in the oscillatory tail. This regime can be qualitatively associated with a shock wave. The front propagation can be described with the help of a simple reduced-order model; the latter delivers a kinetic law, which is almost not sensitive to the fine details of the on-site potential. Besides, it is possible to predict all main characteristics of the transition front, including its velocity, as well as the frequency and the amplitude of the oscillatory tail. Numerical results are in good agreement with the analytical predictions. The suggested approach allows one to consider the effects of an external pre-load, the next-nearest-neighbor coupling and the on-site damping. When the damping is moderate, it is possible to consider the shock propagation in the damped chain as a perturbation of the undamped dynamics. This approach yields reasonable predictions. When the damping is high, the transition front enters a completely different asymptotic regime of a subsonic kink. The gradient nonlinearity generically turns negligible, and the propagating front converges to the regime described by a simple exact solution for a continuous model with linear coupling.
Dynamic and structural evidence of mesoscopic aggregation in phosphonium ionic liquids
Authors: Cosby T. , Vicars Z. , Heres M. , Tsunashima K. , Sangoro J.
Published: February 2018

Mesoscopic aggregation in aprotic ionic liquids due to the microphase separation of polar and non-polar components is expected to correlate strongly with the physicochemical properties of ionic liquids and therefore their potential applications. The most commonly cited experimental evidence of such aggregation is the observation of a low-q pre-peak in the x-ray and neutron scattering profiles, attributed to the polarity alternation of polar and apolar phases. In this work, a homologous series of phosphonium ionic liquids with the bis(trifluoromethylsulfonyl)imide anion and systematically varying alkyl chain lengths on the phosphonium cation are investigated by small and wide-angle x-ray scattering, dynamic-mechanical spectroscopy, and broadband dielectric spectroscopy. A comparison of the real space correlation distance corresponding to the pre-peak and the presence or absence of the slow sub-α dielectric relaxation previously associated with the motion of mesoscale aggregates reveals a disruption of mesoscale aggregates with increasing symmetry of the quaternary phosphonium cation. These findings contribute to the broader understanding of the interplay of molecular structures, mesoscale aggregation, and physicochemical properties in aprotic ionic liquids.
Wettability of AFM tip influences the profile of interfacial nanobubbles
Authors: Teshima Hideaki , Takahashi Koji , Takata Yasuyuki , Nishiyama Takashi
Published: February 2018

To accurately characterize the shape of interfacial nanobubbles using atomic force microscopy (AFM), we investigated the effect of wettability of the AFM tip while operating in the peak force tapping (PFT) mode. The AFM tips were made hydrophobic and hydrophilic by Teflon AF coating and oxygen plasma treatment, respectively. It was found that the measured base radius of nanobubbles differed between AFM height images and adhesion images, and that this difference depended on the tip wettability. The force curves obtained during the measurements were also different depending on the wettability, especially in the range of the tip/nanobubble interaction and in the magnitude of the maximum attractive force in the retraction period. The difference suggests that hydrophobic tips penetrate the gas/liquid interface of the nanobubbles, with the three phase contact line being pinned on the tip surface; hydrophilic tips on the other hand do not penetrate the interface. We then quantitatively estimated the pinning position and recalculated the true profiles of the nanobubbles by comparing the height images and adhesion images. As the AFM tip was made more hydrophilic, the penetration depth decreased and eventually approached zero. This result suggests that the PFT measurement using a hydrophilic tip is vital for the acquisition of reliable nanobubble profiles.
Lamb dip CRDS of highly saturated transitions of water near 1.4 μm
Authors: Kassi S. , Stoltmann T. , Casado M. , Daëron M. , Campargue A.
Published: February 2018

Doppler-free saturated-absorption Lamb dips were measured at sub-Pa pressures on rovibrational lines of H216O near 7180 cm−1, using optical feedback frequency stabilized cavity ring-down spectroscopy. The saturation of the considered lines is so high that at the early stage of the ring down, the cavity loss rate remains unaffected by the absorption. By referencing the laser source to an optical frequency comb, transition frequencies are determined down to 100 Hz precision and kHz accuracy. The developed setup allows resolving highly K-type blended doublets separated by about 10 MHz (to be compared to a HWHM Doppler width on the order of 300 MHz). A comparison with the most recent spectroscopic databases is discussed. The determined K-type splittings are found to be very well predicted by the most recent variational calculations.
Theory of activated glassy dynamics in randomly pinned fluids
Authors: Phan Anh D. , Schweizer Kenneth S.
Published: February 2018

We generalize the force-level, microscopic, Nonlinear Langevin Equation (NLE) theory and its elastically collective generalization [elastically collective nonlinear Langevin equation (ECNLE) theory] of activated dynamics in bulk spherical particle liquids to address the influence of random particle pinning on structural relaxation. The simplest neutral confinement model is analyzed for hard spheres where there is no change of the equilibrium pair structure upon particle pinning. As the pinned fraction grows, cage scale dynamical constraints are intensified in a manner that increases with density. This results in the mobile particles becoming more transiently localized, with increases of the jump distance, cage scale barrier, and NLE theory mean hopping time; subtle changes of the dynamic shear modulus are predicted. The results are contrasted with recent simulations. Similarities in relaxation behavior are identified in the dynamic precursor regime, including a roughly exponential, or weakly supra-exponential, growth of the alpha time with pinning fraction and a reduction of dynamic fragility. However, the increase of the alpha time with pinning predicted by the local NLE theory is too small and severely so at very high volume fractions. The strong deviations are argued to be due to the longer range collective elasticity aspect of the problem which is expected to be modified by random pinning in a complex manner. A qualitative physical scenario is offered for how the three distinct aspects that quantify the elastic barrier may change with pinning. ECNLE theory calculations of the alpha time are then presented based on the simplest effective-medium-like treatment for how random pinning modifies the elastic barrier. The results appear to be consistent with most, but not all, trends seen in recent simulations. Key open problems are discussed with regard to both theory and simulation.
Application of SQUIDs to low temperature and high magnetic field measurements—Ultra low noise torque magnetometry
Authors: Arnold F. , Naumann M. , Lühmann Th. , Mackenzie A. P. , Hassinger E.
Published: February 2018

Torque magnetometry is a key method to measure the magnetic anisotropy and quantum oscillations in metals. In order to resolve quantum oscillations in sub-millimeter sized samples, piezo-electric micro-cantilevers were introduced. In the case of strongly correlated metals with large Fermi surfaces and high cyclotron masses, magnetic torque resolving powers in excess of 104 are required at temperatures well below 1 K and magnetic fields beyond 10 T. Here, we present a new broadband read-out scheme for piezo-electric micro-cantilevers via Wheatstone-type resistance measurements in magnetic fields up to 15 T and temperatures down to 200 mK. By using a two-stage superconducting-quantum interference device as a null detector of a cold Wheatstone bridge, we were able to achieve a magnetic moment resolution of Δm = 4 × 10−15 J/T at maximal field and 700 mK, outperforming conventional magnetometers by at least one order of magnitude in this temperature and magnetic field range. Exemplary de Haas-van Alphen measurement of a newly grown delafossite, PdRhO2, was used to show the superior performance of our setup.
Pedestal dynamics across low to high confinement regime in the HL-2A tokamak
Authors: Liang A. S. , Zhong W. L. , Zou X. L. , Duan X. R. , Yang Z. C. , Wen J. , Xiao G. L. , Jiang M. , Shi Z. B. , Shi P. W. , Chen W. , Song X. M. , Yu D. L. , Yan L. W. , Liu Y. , Yang Q. W. , Dong J. Q. , Ding X. T. , Xu M. ,   HL-2A Team
Published: February 2018

Interactions among pedestal shear flows, turbulence, and the formation of the edge transport barrier have been studied in H-mode plasmas of the HL-2A tokamak by multi-channel Doppler reflectometry with high spatiotemporal resolution. Geodesic acoustic mode (GAM) has been observed during the L-I-H transition. It has been observed that the plasma transits into the I-phase when the mean E×B shear flow reaches a critical value. The bi-spectrum analysis has shown that there is a strong interaction between GAM and limit cycle oscillation (LCO), and the energy transfer is from GAM to LCO, suggesting that GAM can assist the L-I transition. The regulation of the edge turbulence by LCOs helps to build the steep pedestal and initialize the confinement improvement of the plasma. It has been found that the mean E×B shear flow is further increased just before the I-H transition, accompanied by the turbulence suppression, leading to the edge transport reduction and the pedestal formation. It has been demonstrated that the increase of the mean E×B shear flow prior to the L-I and I-H transitions is due to the ion diamagnetic component of Er. These results corroborate that the mean E×B shear flow plays a key role in the L-I and I-H transitions.
PIC simulation of the anode plasma in a high-power hollow cathode diode
Authors: Liu Laqun , Zou Wenkang , Wang Huihui , Guo Fan , Liu Dagang
Published: February 2018

In this paper, the evolution and dynamics of anode plasmas in high-power hollow cathode diodes were studied by particle-in-cell (PIC) simulation. The simulation results show that the ion flow emitted by the anode plasma layer and the increase of the electron current caused by the ion flow will cause a significant decline in the diode impedance in a short time. In addition, the expansion of the anode plasma layer will cause the diode impedance to decrease. The PIC simulation technique is also applied to a high-power hollow cathode diode of a 1.0 MV-LTD generator for anode plasmas, and the PIC simulation results were compared with the experimental data.
Weakly nonlinear incompressible Rayleigh-Taylor instability in spherical and planar geometries
Authors: Zhang J. , Wang L. F. , Ye W. H. , Guo H. Y. , Wu J. F. , Ding Y. K. , Zhang W. Y. , He X. T.
Published: February 2018

The relationship between the weakly nonlinear (WN) solutions of the Rayleigh-Taylor instability in spherical geometry [Zhang et al., Phys. Plasmas 24, 062703 (2017)] and those in planar geometry [Wang et al., Phys. Plasmas 19, 112706 (2012)] is analyzed. In the high-mode perturbation limit (Pn(cos θ), n≫1), it is found that at the equator, the contributions of mode P2n along with its neighboring modes, mode P3n along with its neighboring modes, and mode Pn at the third order along with its neighboring modes are equal to those of the second harmonic, the third harmonic, and the third-order feedback to the fundamental mode, respectively, in the planar case with a perturbation of the same wave vector and amplitude as those at the equator. The trends of WN results in spherical geometry towards the corresponding planar counterparts are found, and the convergence behaviors of the neighboring modes of Pn, P2n, and P3n are analyzed. Moreover, the spectra generated from the high-mode perturbations in the WN regime are provided. For low-mode perturbations, it is found that the fundamental modes saturate at larger amplitudes than the planar result. The geometry effect makes the bubbles at or near the equator grow faster than the bubbles in planar geometry in the WN regime.
Effects of pressure and incident field on visible light intensity from microwave nitrogen breakdown
Authors: Zhao Pengcheng , Chang Chao , Guo Lixin , Cheng Qi
Published: February 2018

A model consisting of spatially averaged continuity equations for electrons and excited atoms, equations of electron momentum and energy, and an equation of photon emission is used to calculate the photon emission rate during microwave nitrogen breakdown, in order to estimate the visible light intensity. The effects of nitrogen pressure and the incident field on the photon emission rate are analyzed, when the electron density reaches the maximum value above which no ionization occurs. As nitrogen pressure increases, the photon emission rate first increases to a maximum, and then decreases. The simulated dependence of the photon emission rate on pressure is qualitatively consistent with the experimental observation. As the incident field increases, the photon emission rate increases, and the pressure corresponding to the maximum photon emission rate increases. The simulated results for breakdown electric fields and delay times agree very well with experimental data.
Thermodynamics of viscoelastic rate-type fluids with stress diffusion
Authors: Málek Josef , Průša Vít , Skřivan Tomáš , Süli Endre
Published: February 2018

We propose thermodynamically consistent models for viscoelastic fluids with a stress diffusion term. In particular, we derive variants of compressible/incompressible Maxwell/Oldroyd-B models with a stress diffusion term in the evolution equation for the extra stress tensor. It is shown that the stress diffusion term can be interpreted either as a consequence of a nonlocal energy storage mechanism or as a consequence of a nonlocal entropy production mechanism, while different interpretations of the stress diffusion mechanism lead to different evolution equations for the temperature. The benefits of the knowledge of the thermodynamical background of the derived models are documented in the study of nonlinear stability of equilibrium rest states. The derived models open up the possibility to study fully coupled thermomechanical problems involving viscoelastic rate-type fluids with stress diffusion.
Pressure dependence of an ion beam accelerating structure in an expanding helicon plasma
Authors: Zhang Xiao , Aguirre Evan , Thompson Derek S. , McKee John , Henriquez Miguel , Scime Earl E.
Published: February 2018

We present measurements of the parallel ion velocity distribution function and electric field in an expanding helicon source plasma plume as a function of downstream gas pressure and radial and axial positions. The ion beam that appears spontaneously in the plume persists for all downstream pressures investigated, with the largest parallel ion beam velocities obtained for the lowest downstream pressures. However, the change in ion beam velocity exceeds what would be expected simply for a change in the collisionality of the system. Electric field measurements confirm that it is the magnitude of the potential structure responsible for accelerating the ion beam that changes with downstream pressure. Interestingly, the ion density radial profile is hollow close to the end of the plasma source for all pressures, but it is hollow at downstream distances far from the source only at the highest downstream neutral pressures.
Curvature and bottlenecks control molecular transport in inverse bicontinuous cubic phases
Authors: Assenza Salvatore , Mezzenga Raffaele
Published: February 2018

We perform a simulation study of the diffusion of small solutes in the confined domains imposed by inverse bicontinuous cubic phases for the primitive, diamond, and gyroid symmetries common to many lipid/water mesophase systems employed in experiments. For large diffusing domains, the long-time diffusion coefficient shows universal features when the size of the confining domain is renormalized by the Gaussian curvature of the triply periodic minimal surface. When bottlenecks are widely present, they become the most relevant factor for transport, regardless of the connectivity of the cubic phase.
Continuous stacking computational approach based automated microscope slide scanner
Authors: Murali Swetha , Adhikari Jayesh Vasudeva , Jagannadh Veerendra Kalyan , Gorthi Sai Siva
Published: February 2018

Cost-effective and automated acquisition of whole slide images is a bottleneck for wide-scale deployment of digital pathology. In this article, a computation augmented approach for the development of an automated microscope slide scanner is presented. The realization of a prototype device built using inexpensive off-the-shelf optical components and motors is detailed. The applicability of the developed prototype to clinical diagnostic testing is demonstrated by generating good quality digital images of malaria-infected blood smears. Further, the acquired slide images have been processed to identify and count the number of malaria-infected red blood cells and thereby perform quantitative parasitemia level estimation. The presented prototype would enable cost-effective deployment of slide-based cyto-diagnostic testing in endemic areas.
Free energy dissipation of the spontaneous gating of a single voltage-gated potassium channel
Authors: Wang Jia-Zeng , Wang Rui-Zhen
Published: February 2018

Potassium channels mainly contribute to the resting potential and re-polarizations, with the potassium electrochemical gradient being maintained by the pump Na+/K+-ATPase. In this paper, we construct a stochastic model mimicking the kinetics of a potassium channel, which integrates temporal evolving of the membrane voltage and the spontaneous gating of the channel. Its stationary probability density functions (PDFs) are found to be singular at the boundaries, which result from the fact that the evolving rates of voltage are greater than the gating rates of the channel. We apply PDFs to calculate the power dissipations of the potassium current, the leakage, and the gating currents. On a physical perspective, the essential role of the system is the K+–battery charging the leakage (L–)battery. A part of power will inevitably be dissipated among the process. So, the efficiency of energy transference is calculated.
Crisis or the media?
Authors: Patrona Marianna
Published: February 2018

This is the introduction to the edited volume which clarifies the main conceptual and analytical framework adopted in the book. In this approach, ‘crisis’ is viewed as a form of mediated social practice and is placed within the framework of a broader ‘politics of crisis’ brought to life in and by the media. The chapter reviews the relevant literature on mediated representations of and discourses on crisis, and provides an overview of the chapters that follow.
Expressions of blame for the Global Financial Crisis in US, UK and Australian opinion texts
Authors: Cope Jennifer
Published: February 2018

The Global Financial Crisis has had a devastating effect on many economies, with reverberations still being felt today. While the media has focused on the Crisis in affected regions, there is a surprising lack of research on the actual discourse used by key players to express blame and responsibility for the Crisis. This chapter provides an in-depth comparative analysis between the expressions of blame in American, British and Australian newspaper opinion texts, written by authors from differing political backgrounds. It finds that communication strategies of blame are directly and indirectly attributed, rather than resisted or avoided. The chapter is developed from a larger discourse study by Cope (2016), and looks specifically at the relationship between political authors and positioning.
“All good people have debts”
Authors: Aitaki Georgia
Published: February 2018

Building on the notion of the Greek crisis as a discursive event and revisiting theories about the sociocultural role of television fiction, this chapter introduces the latter as a framing mechanism through which events of the social world are defined and assessed. By uncovering the dominant interpretative frames underlying the story, setting, characters and plot of the popular Greek television comedy Piso Sto Spiti (MEGA channel, 2011–2013), this analysis illustrates television fiction’s contribution to the construction of the root causes of the crisis as tied to the cultural traits of Greeks, the impossibility of change and the futility of an alternative, left-wing consideration of the crisis, as well as an attempt to morally assess the situation at hand.
Gender in “crisis”, everyday sexism and the Twittersphere
Authors: Smith Angela
Published: February 2018

This chapter will explore how the rejection of the claims for equality are represented in the technology of the twenty-first century, but at the same time embody the language of a pre-feminist world and can thus be seen to at once empower and restrict feminist discourse. In this way, the crisis in gender relations is one that emerges in the 1990s in Westernised contexts and continues to develop into the twenty-first century, contributing to the emergence of a Fourth Wave of feminist action. As such, “crisis” is employed in this chapter to explore how various small events, seemingly insignificant in isolation, have been raised to public notice through social media to enhance the emergence of Fourth Wave Feminism in the last ten years.
Phonological categories and their manifestation in child phonology
Authors: Rose Yvan
Published: February 2018

The nature of phonological representations and of their acquisition by language learners has been a subject of debate since at least the 1970s. Vihman and Croft (2007) recently proposed the ‘Radical’ Templatic approach to phonology, which formally rejects segmental features as independent units of phonological representation, in spite of their central relevance within mainstream theories of phonology since at least the 1940s. In this chapter, I emphasize that abstract categories are in fact central to our characterization of phonological systems and their acquisition by language learners. I discuss longitudinal data on the development of consonants and consonant clusters in the productions of Catootje, a Dutch-learning child. I highlight several categorical effects that are readily captured in models of phonological development which embrace abstract units such as features and syllable constituents.
Bootstrapping lexical and syntactic acquisition
Authors: Brusini Perrine , de Carvalho Alex , Dautriche Isabelle , Gutman Ariel , Cauvet Elodie , Millotte Séverine , Amsili Pascal , Christophe Anne
Published: February 2018

How does language acquisition start? Having access to words and their meaning should help infants to learn about syntax, but learning about word meaning would be facilitated if infants had access to syntactic structure (Gleitman 1990). Phrasal prosody and function words may bootstrap lexical and syntactic acquisition. Infants have access to phonological phrases, and they use these to constrain the syntactic analysis of utterances by 18 months. At that same age, they can use function words to infer the syntactic category of unknown content words (nouns vs. verbs) and guess their plausible meaning (object vs. action). Moreover, computational work suggests that infants might be able to learn noun and verb contexts by generalizing from a small number of known words (the semantic seed).
New perspectives on input-output dynamics
Authors: Bassano-Bonhommo Dominique , van Geert Paul
Published: February 2018

This study addresses the role of input, i.e., child-directed speech, in child language acquisition. Proposing a dynamic approach of input-output relationships, we examine the development of noun determiners in the spontaneous production data of three monolingual children between one and three years old. Analyses show explosions in determiner use in the three children, although these vary in timing and amplitude. Such explosions are not found in the input, which rather presented striking fluctuations. Dynamic modeling (an extension of the Scaffolding Model) shows corresponding changes over time in child speech and child-directed speech, although the patterns are different across children. This argues for the idea of mutual influences between input and output, congruent with transactional adaptation models.
Referential features, speech genres and activity types
Authors: Salazar-Orvig Anne , Marcos Haydée , Heurdier Julien , da Silva-Genest Christine
Published: February 2018

Based on a dialogic theoretical framework, this chapter explores the influence of speech genres and activities on the use of referring expressions. The study examines a corpus of 25 dialogues of French speaking children aged between 1;10 and 2;04 in various activities. Results show that referring expressions are not homogenously used throughout activities and genres. Everyday activities increase the use of nouns and strong demonstrative pronouns, games with toys positively affect the use of strong demonstrative pronouns and iconic material entails a more frequent use of clitic demonstratives and to a lesser extent of 3rd person pronouns. However, discourse in activities is made of various speech genres which strongly affect the use of clitic pronouns. Clitic demonstratives are preferred for labeling and evaluation but 3rd person pronouns are used for description and narratives. The discussion deals with the way these associations could be factors accounting for children’s early choice of referring expressions.
Online sentence processing in simultaneous French/Swedish bilinguals
Authors: Kail Michèle , Kihlstedt Maria , Bonnet Philippe
Published: February 2018

Within the Competition Model, cue validity and cue cost can serve to make predictions about real-time sentence processing in a cross-linguistic perspective. Previous research with monolingual children and adults in French (Kail 2004) and Swedish (Kail et al. 2012) proposed that cue cost is determined by contextual and structural information, word order and morphology. On the basis of online grammaticality judgments, we investigated whether these cue cost constraints are equally efficient and follow the same hierarchy in simultaneous French/Swedish bilinguals and in their monolingual counterparts. Although bilinguals were slower and less accurate, the weight of each cue cost component was similar for both groups. Bilinguals’ longer detection times are linked to specific interactions between cue cost components not observed in monolinguals. This result is compatible with the cognitive cost implied by the need to inhibit the non-relevant language during bilingual processing.
Motion expression in children’s acquisition of French Sign Language
Authors: Sallandre Marie-Anne , Schoder Camille , Hickmann Maya
Published: February 2018

Much research has examined the development of motion expression, but little is known about this domain in sign language. This study examines how signers (Deaf children aged 5–10 and adults) of French Sign Language (LSF) described clips showing voluntary motion events with variable Paths and Manners. Using mainly iconic structures, children frequently expressed both Path and Manner early on. However, responses varied with the structures used and increased with age for some event types (downward motion, boundary crossing). In addition, serial constructions increased, typically expressing two perspectives (observer and character). Finally, young children did not always provide relevant locative information (particularly with crossing events) but these cases decreased. In conclusion, iconicity partially invites signers to combine motion components, notwithstanding variation in structure and developmental changes observed with some event types.
Non-literal language comprehension
Authors: Dardier Virginie , Champagne-Lavau Maud
Published: February 2018

Nonliteral language includes any utterance that produces an apparent need to go beyond what is literally stated, in order to comprehend the speaker’s communicative intent and, consequently, to understand the meaning of these utterances in a given context. Impaired comprehension of indirect requests has been reported in adults with acquired brain lesions. There is little available knowledge on the development of pragmatic skills in children and adolescents with brain damage. Do children with brain damage differ from brain-damaged adults in request comprehension? To answer the question, this chapter adopts a developmental perspective, describing the results of studies with adults and children with acquired brain lesions.
Plantation forests: a review of recent developments.
Authors: Griess V. C. , Jackson D. J. , Werner H. G.
Published: February 2018

For the review at hand, Clarivate Analytic's web of science search platform was searched for the keyword combination
forest
+
plantation
. The search found 944 articles with the mentioned keywords in their topic that were published between 2010 and 2017. The top 3 subtopics identified were
soil
,
carbon and water
in order of abundance. The overview over current research in each of these subtopics to plantation forests naturally show strong overlaps with biodiversity as well as ecological aspects of plantation forests. Given the fact that the assessed research is coming from a wide geographic area, it is specifically interesting to see that general challenges or expectations towards plantation forests do not differ dramatically between those geographies. Overall, there is clear consensus that more plantation forests will be required to meet increasing timber demand, and that productivity in existing forests should be increased. The conversion of natural forests into plantation forests comes with unfavourable consequences with respect to many ecological parameters in the majority of the cases. However, conversion of abandoned or degraded lands into forest plantations can have positive consequences. Overall, there is an increasing interest in plantation forests that are managed for other ecosystem services alongside timber production. Initial research into the possibilities associated with close-to-nature management alternatives, such as mixing species, or uneven-aged management show promising results, consolidating ecological benefits and economic expectations.
Retrospective studies of abattoir zoonoses in Nigeria: public health implications.
Authors: Fasanmi O. G. , Ayodeji I. O. , Oloso N. O. , Fasina F. O.
Published: February 2018

Abattoirs are major sources of valuable information for animal disease outbreaks, but also an environment for transmission of meat-borne zoonoses, which may constitute a major threat to public health and food safety. This study aims to identify common abattoir zoonoses, the geographic distribution and the risk factors predisposing to their spread across Nigeria; and also to evaluate the prevalence estimates of abattoir zoonoses in human and slaughter animals. A systematic search of regional databases based on set criteria, yielded 47 relevant articles scrutinized critically to find the best available evidences to support the study purpose. All the publications which cut across the six geo-political regions of Nigeria carried out confirmatory diagnosis of the causative organisms. The results yielded 11 human and 53 slaughter animal causal organisms of abattoir zoonoses and obligate pathogens of human infections. They constitute bacterial (68.2%), helminths (21.2%), viral (6%) and protozoan (4.6%) due to infection or contamination. There was an increasing trend in occurrence of abattoir zoonoses as the year of studies progressed; also there were corresponding increase in human cases of abattoir zoonoses as the occurrence in slaughter animals' increased from 2001 to 2016. Some risk factors identified for the human abattoir zoonoses include; butchers with open wounds, occupational exposure of greater than 5 years and consumption of raw meat. Abattoir workers are at higher risk of being exposed to abattoir zoonoses due to occupational hazards; also consumer's choice of meat is significantly associated with the type of meat. Abattoir zoonoses exist in Nigeria, but the occurrence, spread and prevalence can be mitigated through proper meat inspection, improved hygiene and creating greater awareness of risks and avoidance.
Optimizing ecosystem services to deliver multiple benefits.
Authors: Everard M.
Published: February 2018

The inherently systemic concept of ecosystem services recognizes multiple, qualitatively differing societal benefits, yet most services remain overlooked by contemporary markets and policy drivers contributing to ecosystem degradation. Societal transition from reductive, reactive decision-making about ecosystem management and policy to one founded on a systemic basis is limited by the lag effect of legacy world views and fragmented formal and informal policies. Transformation to systemically based societal decision-making norms may be accelerated by recognizing that desired services should not dominate decision-making, instead of constituting 'anchor services' around which outcomes for linked ecosystem services can be optimized with the involvement of their beneficiaries. Deliberative processes can generate innovations in ecosystem use and management, including identification of 'systemic solutions' that deliberately optimize outcomes across a spectrum of linked ecosystem services. This service-optimizing approach is more equitable through addressing outcomes for diverse service beneficiaries, more economically efficient by recognizing and balancing linked benefits and disbenefits, and more resilient by refocusing on service-producing ecosystem processes. New policies and tools may be required, but the application of the ecosystem services framework to evaluate outcomes in existing tools enables rapid, incremental progress. Systemic thinking about ecosystem dependencies and impacts is relevant to all policy areas and sectors of society.