bluuebunny/crossref_metadata_2025 huggingface dataset:
Rotation of small diatomics in water–ethanol mixture: Multiple breakdowns of hydrodynamic predictions
Authors: Nair Anjali S. , Kumar Shubham , Acharya Subhajit , Bagchi Biman
Published: July 2020

We study the rotational and translational dynamics of three small important linear molecules, namely, carbon monoxide (CO), nitric oxide (NO), and cyanide ion (CN−) in water–ethanol mixtures, at different compositions. Here, we report a detailed study of the dynamics of these diatomics in water–ethanol binary mixtures for the first time. We find multiple anomalous results, namely, (i) faster rotational motion of CO and NO than CN−, (ii) larger translational diffusion of CO and NO in pure ethanol than in water but the reverse for CN−, (iii) a pronounced anomaly in the composition dependence of translational–rotational dynamics at low ethanol composition, and (iv) a re-entrant type behavior in the viscosity dependence of orientational relaxation. We compare our simulation result-based observations with the existing experimental results wherever available and find that the simulation results are in reasonably good agreement with the experiments. We implement, for the first time, a calculation of the rotational binary friction following the sophisticated scheme of Evans and co-workers. We also calculate the hydrodynamic predictions for the solute molecules. On comparison with the simulation and experimental results, we find that neither the rotational binary friction nor the hydrodynamic expressions (both stick and slip) can reproduce the results. To rectify the situation, we develop a detailed mode-coupling theory and suggest that such an approach if completely implemented can provide a more reliable description than the hydrodynamic approach. Many of our results could be tested in experimental studies because these linear molecules are amenable to spectroscopic studies, such as 2D-IR.
A new micro/nano-touch-trigger probe using an optoelectronic sensor with a wedge prism
Authors: Xu P. , Li R. J. , Jin X. W. , Wang P. Y. , Chen L. J. , Fan K. C.
Published: July 2020

In this paper, we propose a new touch-trigger probe with high precision and a large permissible measurement range. A wedge prism was used in the sensing unit to achieve 3D detection using only one optoelectronic sensor. The measurement range was expanded from ±8 µm to ±14 µm through the new optical structure. The probe has uniform stiffness and uniform sensitivity. Some experiments were performed to investigate the performance of the probe. It was found that the probe has a resolution of 10 nm and a repeatability of less than 9.1 nm. The applicability of the probe was also verified.
Interplay between ferroelectric and quantum paraelectric instabilities in Eu0.7Ba0.3TiO3 Perovskite oxide: Defect dipoles and ferroelectric instability induced by oxygen vacancies
Authors: Jaffari Ghulam Hassnain , Iqbal Asad Muhammad
Published: July 2020

Investigation of intrinsic response and proper selection/tailoring of perovskite oxides is challenging and essential to understand the origin of various instabilities. For this purpose, Eu0.7Ba0.3TiO3-δ is shown to be a prime candidate. Coexistence of quantum paraelectric and ferroelectric instabilities with Ba substitution and variation of oxygen vacancies has been demonstrated in a specifically chosen composition. Random distribution of Ba2+ ions in a stoichiometric composition brings the system toward phase boundary. Interestingly, in the space charge unactivated temperature regime, the role of intentionally introduced oxygen vacancies is to induce ferroelectric character through the formation of local defect dipoles.
Versatile two-dimensional boron monosulfide polymorphs with tunable bandgaps and superconducting properties
Authors: Fan Dong , Lu Shaohua , Chen Chengke , Jiang Meiyan , Li Xiao , Hu Xiaojun
Published: July 2020

The typical two-dimensional semiconductors, group IIIA chalcogenides, have garnered tremendous interest for their outstanding electronic, mechanical, and chemical properties. However, so far, there have been rare reports on boron monosulfides (BS) binary material. Here, four two-dimensional BS sheets, namely, the α-, β-, γ-, and δ-BS sheets, are proposed and discussed from first principles calculations. State-of-the-art calculations reveal all these structures are thermally and dynamically stable, indicating the potential for experimental synthesis. Specifically, for α-BS, it has a calculated exfoliation energy of 0.96 J m−2, suggesting that the preparation of α-BS is feasible by the exfoliation of bulk rhombohedral-BS. Our results show that α-, β-, and γ-BS are semiconductors, whereas δ-BS is a metallic system. Remarkably, our calculations indicate that δ-BS is a superconductor with a large electron-phonon coupling (λ ≈ 1.51), leading to a high superconducting critical temperature (Tc ≈ 21.56 K), which is the interesting property with intrinsic superconducting among all two-dimensional group IIIA chalcogenides. The potential of semiconducting BS monolayers as the gas-sensor or thermoelectric materials is also demonstrated.
Mobility of near surface MOVPE grown InGaAs/InP quantum wells
Authors: Södergren Lasse , Garigapati Navya Sri , Borg Mattias , Lind Erik
Published: July 2020

In this work, we study the electron mobility of near surface metal organic vapor phase epitaxy-grown InGaAs quantum wells. We utilize Hall mobility measurements in conjunction with simulations to quantify the surface charge defect density. Buried quantum wells are limited by polar optical phonon scattering at room temperature. In contrast, the quantum wells directly at the surface are limited by remote charge impurity scattering from defects situated at the III–V/oxide interface or inside the oxide, showing a mobility of 1500 cm2/V s. Passivating the InGaAs surface by depositing an oxide reduces the amount of defects at the interface, increasing the mobility to 2600 cm2/V s.
Design and experimental results of a laser-ignited solid-propellant-fed magnetoplasmadynamic thruster
Authors: Ou Yang , Wu Jianjun , Zhang Yu
Published: July 2020

A laser-ignited solid-propellant-fed magnetoplasmadynamic thruster (LISMPDT) is developed and tested. In this kind of thruster, a solid propellant is placed in a hollow cathode tube. When it works, the propellant is ablated and partially ionized by the laser; then, the plasma flow enters the chamber and is accelerated by the electromagnetic interaction. Unlike the typical magnetoplasmadynamic thrusters, almost any solid material can be used as a propellant in the LISMPDT; no tanks, valves, or piping systems are required for the propulsion system. Moreover, as the particles involved in the discharge process are produced from the laser ablation process, it would lead to a directed initial velocity and higher ionization. Meanwhile, a part of the energy serving the thruster could also be derived from the laser quasi as an add-on to the discharge energy with the separation of the ignition power and the ignition power unit from the thruster system. Experiments on the discharge characteristics and thrust performances were conducted and analyzed. The results validated the feasibility of the LISMPDT, and the maximal specific impulse reached ∼780 s, while the maximal thrust efficiency was expected to be about 9% under different operating conditions. It was also found that increasing the initial discharge voltage would effectively improve the propulsion performance while a longer laser pulse width led to reduced performance.
Interfacial charge and strain effects on lanthanum doped barium stannate thin film under ferroelectric gating
Authors: Cui Jiameng , Wang Jianlin , Huang Haoliang , Zhao Zhibo , Yang Yuanjun , Zhang Yuanxi , Fu Zhengping , Lu Yalin
Published: July 2020

Interfacial charge and strain are two coupling effects in semiconductor/ferroelectric epitaxial heterostructures, which are pivotal for use in tailoring functionalities in devices. In this work, La0.04Ba0.96SnO3/0.7Pb(Mg1/3Nb2/3)O3–0.3PbTiO3 heterostructures with varying film thicknesses were prepared in order to understand both charge and strain's contributions to the electric-field induced resistance change. The relative resistance change to the lattice strain remains almost unchanged in those thicker films, while increases a little bit in those thinner films. This slight increase is related to the substrate constraint near the interface and follows Freund's strain relaxation model during the dynamic strain induced by the piezoelectric switch. A depletion layer model was also established to simulate the electroresistance variation from the interfacial charge effect. The depletion layer involves an equilibrium between capture and release of electrons by the acceptor-like defects near the interface region. The resistance change vs electric field evolves from a butterfly-like shape to a square-like when decreasing the film thickness, due to the joint effect of strain and interfacial polarization screening charge. This study provides an insight into understanding heteroepitaxial coupling and exploring their potential applications in oxide electronic devices.
Toroidal modeling of anisotropic thermal transport and energetic particle effects on stability of resistive plasma resistive wall mode
Authors: Bai Xue , Liu Yueqiang , Gao Zhe , Hao Guangzhou
Published: July 2020

Effects of anisotropic thermal transport on the linear stability of the resistive plasma resistive wall mode (RPRWM) are investigated by the magnetohydrodynamic-kinetic hybrid code MARS-K [Liu et al., Phys. Plasmas 15, 112503 (2008)], including the kinetic contribution from energetic particles (EPs). It is found that thermal transport can further stabilize the RPRWM in the presence of drift kinetic contributions from EPs. This is different from the fluid model, which always predicts destabilization of the mode by thermal transport. Furthermore, the thermal transport effect is found to amplify the role played by an adiabatic term, associated with the radial distribution of EPs' birth energy, in modifying the mode stability as well as the mode eigenfunction. The shape of the equilibrium profiles of EPs, in particular that of the temperature, is also found to strongly affect the mode stabilization. This profile effect is more pronounced in the absence of thermal transport. MARS-K computations show that the stabilizing effect by thermal transport is more likely to occur at slower plasma rotation and lower EP energy.
Correlations between the ductility and medium-range order of bulk metallic glasses
Authors: A. Davani Farnaz , Hilke Sven , Rösner Harald , Geissler David , Gebert Annett , Wilde Gerhard
Published: July 2020

Understanding ductility or brittleness of monolithic bulk metallic glasses requires detailed knowledge of the amorphous structure. The medium-range order (MRO) of ductile Pd40Ni40P20 and brittle Zr52.5Cu17.9Ni14.6Al10Ti5 (Vit105) was characterized prior to and after notched three-point bending tests using variable-resolution fluctuation electron microscopy. Here, we show the presence of a second larger MRO correlation length in the ductile material, which is not present in the brittle material. The second larger correlation length accounts for an increased heterogeneity, which seems to enable an easier shear band formation and thus explain the difference in deformability.
How IQ depends on the running mode of brain network?
Authors: Cao Liang , Liu Zonghua
Published: July 2020

Increasing evidence has shown that intelligence quotient (IQ) depends not only on the aspect of phenomenology such as the size of brain and sexuality but also on the topology of the brain network. We here try to get a deeper understanding by asking how the running mode of the brain network influences IQ. We introduce a parameter α to represent the trade-off between wiring cost and processing efficiency and figure out the optimal value of α by the approach of network reconstruction. A negative correlation between optimal index α and IQ is revealed. To further find out the mechanism for the functional difference between males and females, we move to the local level of brain regions and study the relationship between regional optimal α and IQ. We find that the Pearson coefficients of males are significantly different from that of females, including both global and regional levels. These findings show that the functional differences between individuals, including the differences between males and females, are closely related to the different running modes of their brain networks.
Dynamics and bifurcations of a family of piecewise smooth maps arising in population models with threshold harvesting
Authors: Liz Eduardo , Lois-Prados Cristina
Published: July 2020

We study a discrete-time model for a population subject to harvesting. A maximum annual catch H is fixed, but a minimum biomass level T must remain after harvesting. This leads to a mathematical model governed by a continuous piecewise smooth map, whose dynamics depend on two relevant parameters H and T. We combine analytical and numerical results to provide a comprehensive overview of the dynamics with special attention to discontinuity-induced (border-collision) bifurcations. We also discuss our findings in the context of harvest control rules.
Global well-posedness and infinite propagation speed for the N − abc family of Camassa–Holm type equation with both dissipation and dispersion
Authors: Zhang Zaiyun , Liu Zhenhai , Deng Youjun , Huang Chuangxia , Lin Shiyou , Zhu Wen
Published: July 2020

In this paper, we consider the Cauchy problem for the N − abc family of the Camassa–Holm type equation with both dissipation and dispersion. First, we establish the global well-posedness of the strong solutions under certain conditions on the initial datum. Then, we investigate the propagation speed with compactly supported initial data. This result improves earlier ones reported in the literature, such as those by Novruzov et al. [J. Differ. Equations 257, 4525–4541 (2014)], Hwang and Moon [Electron. Res. Arch. 28(1), 15–25 (2020)], and Himonas and Thompson [J. Math. Phys. 55, 091503 (2014)].
X-ray absorption and photoemission spectroscopy of bulk insulating materials using graphene
Authors: Suzuki Satoru , Haruyama Yuichi , Yamaguchi Akinobu , Yamamoto Tomoki , Yoshizumi Takuya , Fujii Ayaka , Nakashima Seiji , Fuchiwaki Yakumo , Fujisawa Hironori , Ohkochi Takuo , Ishihara Mari , Sumida Hirosuke
Published: July 2020

The charging effect often complicates photoemission spectroscopy and x-ray absorption spectroscopy of an insulating material. Here, monolayer graphene was used as a conductive layer to prevent the charging effect of insulating substrates such as glass and LiNbO3. Charging-free spectra were obtained with various photon energies ranging from vacuum ultraviolet light to hard x-rays. This method could also be applied to photoemission spectroscopy of epoxy adhesives and to photoemission electron microscopy of an insulating film. Photoelectron transmissivities for the transferred graphene film were evaluated over a wide kinetic energy range from 29 to 7910 eV. A minimum transmissivity of ∼0.1 was found at a kinetic energy of ∼60 eV, which rose to 0.86 at 7910 eV. In terms of the kinetic energy dependence of the transmissivity, this method is especially suitable for conventional and hard x-ray photoelectron spectroscopy.
Accelerated multimodel Newton-type algorithms for faster convergence of ground and excited state coupled cluster equations
Authors: Kjønstad Eirik F. , Folkestad Sarai D. , Koch Henrik
Published: July 2020

We introduce a multimodel approach to solve coupled cluster equations, employing a quasi-Newton algorithm for the ground state and an Olsen algorithm for the excited states. In these algorithms, both of which can be viewed as Newton algorithms, the Jacobian matrix of a lower level coupled cluster model is used in Newton equations associated with the target model. Improvements in convergence then imply savings for sufficiently large molecular systems, since the computational cost of macroiterations scales more steeply with system size than the cost of microiterations. The multimodel approach is suitable when there is a lower level Jacobian matrix that is much more accurate than the zeroth order approximation. Applying the approach to the CC3 equations, using the CCSD approximation of the Jacobian, we show that the time spent to determine the ground and valence excited states can be significantly reduced. We also find improved convergence for core excited states, indicating that similar savings will be obtained with an explicit implementation of the core-valence separated CCSD Jacobian transformation.
Tunable wetting surfaces with interacting cavities via femtosecond laser patterning and wet etching
Authors: Deng Chun , Ki Hyungson
Published: July 2020

This paper presents the production of bioinspired slippery glass surfaces with interacting cavities via wet-etching-assisted femtosecond laser fabrication. A femtosecond laser irradiates a glass surface to fabricate microvoid arrays inside the substrate. Then, wet etching is performed to induce microcavities on the sample surface. With laser-induced selective etching, the region below the substrate surface is etched faster, thereby developing microcavities. The microvoid separation distance is found to be important for controlling the contact angle (CA) of the liquid wetting the surface. By choosing an adequate microvoid separation distance and etching time, interacting/interconnected cavities can be successfully fabricated. CAs are expected to be tuned from almost 0° to 137° ± 2.5° based on the cavity separation distance and the processes used (laser patterning, etching, and silanization). These interconnected structures fabricated with small separation distances (e.g., 10 μm) can lock in an infused lubricating liquid and form a stable, inert, slippery interface, known as a slippery liquid-infused porous surface, which acts as a smooth cushion for liquid repellence. Moreover, the infused liquid can significantly increase the transmittance owing to the index matching effect. Such slippery surfaces could be used in several self-cleaning, optical-sensing, and biomedical applications.
Active dopant profiling and Ohmic contacts behavior in degenerate n-type implanted silicon carbide
Authors: Spera Monia , Greco Giuseppe , Severino Andrea , Vivona Marilena , Fiorenza Patrick , Giannazzo Filippo , Roccaforte Fabrizio
Published: July 2020

This Letter reports on the active dopant profiling and Ohmic contact behavior in degenerate P-implanted silicon carbide (4H-SiC) layers. Hall measurements showed a nearly temperature-independent electron density, corresponding to an electrical activation of about 80% of the total implanted dose. Using the Hall result as calibration, the depth resolved active P-profile was extracted by scanning capacitance microscopy (SCM). Such information on the active P-profile permitted to elucidate the current injection mechanism at the interface of annealed Ni Ohmic contacts with the degenerate n-type 4H-SiC layer. Modeling the temperature dependence of the specific contact resistance with the thermionic field emission mechanism allowed extracting a doping concentration of 8.5 × 1019 cm−3 below the metal/4H-SiC interface, in excellent agreement with the value independently obtained by the SCM depth profiling. The demonstrated active dopant profiling methodology can have important implications in the 4H-SiC device technology.
Room-temperature operation of c-plane GaN vertical cavity surface emitting laser on conductive nanoporous distributed Bragg reflector
Authors: ElAfandy Rami T. , Kang Jin-Ho , Li Bingjun , Kim Tae Kyoung , Kwak Joon Seop , Han Jung
Published: July 2020

Technological feasibility of III-nitride vertical cavity surface emitting laser (VCSEL) has been hindered by the lack of an electrically conductive, easily manufacturable, wide reflection stop band distributed Bragg reflector (DBR). Here, we present the first electrically injected III-nitride VCSEL on an electrically conductive DBR using nanoporous (NP) GaN. The measured threshold current density and the maximum light output power were 42 kA/cm2 and 0.17 mW, respectively, at 434 nm. Vertical injection was demonstrated and showed no deterioration in the threshold current density or slope efficiency, demonstrating the feasibility of vertical injection in NP GaN VCSELs. Filamentary lasing was observed, and its effect on the slope efficiency and the lasing linewidth is studied. Initial measurements showing the correlation between the measured high threshold current density and surface undulations are presented and discussed.
Barkhausen noise analysis of thin film ferroelectrics
Authors: Yazawa Keisuke , Ducharne Benjamin , Uchida Hiroshi , Funakubo Hiroshi , Blendell John E.
Published: July 2020

The first direct Barkhausen noise measurement in a ferroelectric thin film is presented. The Barkhausen noise energy loop is reconstructed from the measured Barkhausen noise and is closely related to the classic ferroelectric P vs E hysteresis loop. Grain boundaries act as a dominant ferroelectric domain wall pinning site in a polycrystalline thin film based on the calculated domain wall jump distance using the Barkhausen noise frequency. The technique is promising for the measurement of ferroelectric switching dynamics, and provides a physical insight for improving application performance.
On the breakup of a permeating oil droplet in crossflow filtration: Effects of viscosity contrast
Authors: Salama Amgad
Published: July 2020

The critical velocity of dislodgment of a permeating oil droplet in crossflow filtration is an important parameter in the analysis of the filtration of produced water systems using membrane technology. In this work, the effects of the viscosity contrast between the droplet and the surrounding fluid on the critical velocity of dislodgment are investigated. In the limit when the viscosity of the droplet approaches infinity, the gripping of the crossflow field on the droplet is maximum. When the viscosity contrast is finite, the smaller the viscosity contrast is, the smaller the gripping becomes. In order to highlight this effect, a comprehensive computational fluid dynamics study is conducted. A permeating droplet in the crossflow field is considered with the viscosity contrast ranging within two orders of magnitude. For each scenario, the critical velocity of dislodgment is determined by increasing the velocity incrementally until breakup occurs for every viscosity contrast. It is found that an increase in the viscosity contrast results in a decrease in the critical velocity of dislodgment. This represents a direct manifestation of the effect of the gripping of the droplet by the crossflow field, which increases as the viscosity contrast increases. Modification of the critical velocity of dislodgment, therefore, needs to be considered to account for this effect of viscosity contrast. The formula that was developed to estimate the critical velocity of dislodgment has been modified, and comparison with simulation gives a very good match.
Bending dynamics of viscoelastic photopolymer nanowires
Authors: Kubacková Jana , Iványi Gergely T. , Kažiková Veronika , Strejčková Alena , Hovan Andrej , Žoldák Gabriel , Vizsnyiczai Gaszton , Kelemen Lóránd , Tomori Zoltán , Bánó Gregor
Published: July 2020

In this work, we demonstrate that the mechanical dynamics of polymer nanowires prepared by two-photon polymerization direct laser writing lithography is strongly influenced by their viscoelastic characteristics. Bending recovery measurements were carried out on cantilevered nanowires deflected by optical tweezers in a liquid environment. The assumption of purely elastic cantilever response (as defined by Young's modulus of the polymer material) fails to explain the observed overdamped oscillatory motion. A mechanical model is proposed to account for the nanowire viscoelastic behavior. The experimental data indicate that the origin of the nanowire viscous component is twofold. Both the partially cross-linked polymer structure and the solvent penetrating the polymer network contribute to frictional forces inside the nanowire. The present results provide guidance for the future design of nanosized polymer devices operated in a dynamic regime.
A fast avalanche Si diode with a 517
μ
m low-doped region
Authors: Kesar Amit S. , Raizman Arie , Atar Gil , Zoran Shoval , Gleizer Svetlana , Krasik Yakov , Cohen-Elias Doron
Published: July 2020

A silicon-avalanche shaper/sharpener is a fast-closing semiconductor switch. For positive voltages, it is activated by a high-voltage pulse at its cathode, and, when turned on, the current through the device rises rapidly. Using Synopsys TCAD software, a p+−n−n+ diode is numerically studied. It was shown that for the case of a high-doped active n region, 1014 cm−3, the breakdown process exhibits a fast electric field propagation, as expected. For a low doped active n region, <1011 cm−3, the electric field spreads uniformly along the structure. For this case, we show that the rise time, of the order of 100 ps, is not limited by the active region thickness, allowing the use of a thicker substrate in order to increase the operating voltage. A p+−n−n+ diode was fabricated on a thick, 525 μm, float-zone n-type Si (100) substrate, with a resistivity of 104 Ω cm. The active region, n<1012 cm−3, was 517 μm. When a stack of five, 8 mm2, diodes was driven by an ∼100 kV, 2.26 ns rise time pulse, the output voltage was 46 kV with the rise time and rise rate per diode of 215 ps and 38.4 kV/ns, respectively. When a single, 4 mm2, diode was driven by a 14 kV, 1 ns rise time pulse, the output on a 50 Ω load was around 8 kV, 100 ps, with a rise rate of 57 kV/ns. These results exceed the present state-of-the-art diodes. Furthermore, the thick active region eliminates current fabrication process difficulties such as deep diffusion or thick epitaxial layers.
Sheep grazing to control weeds enhances soil carbon, not nitrogen
Authors: Sainju Upendra , Hatfield Patrick , Ragen Devon
Published: July 2020

Sheep (Ovis aries L.) grazing on weeds and crop residue during the fallow period may enhance soil carbon (C) and nitrogen (N) through urine and faeces returned to the soil. We compared sheep grazing, tillage, and herbicide application as weed management practices on soil total C (STC), total N (STN), ammonium (NH4+)-N, and nitrate (NO3–)-N contents in a dryland 5-year crop rotation from 2012 to 2015 in the northern Great Plains, USA. The treatments were sheep grazing with no chemical input in organic crop production (GO), minimum tillage with chemical inputs (MT), and conventional tillage with no chemical input in organic crop production (TO). The 5-year crop rotation was safflower (Carthamus tinctorius L.)/sweet clover (Melilotus officinalis L.) cover crop–sweet clover cover crop–winter wheat (Triticum aestivum L.)–lentil (Lens culinaris L.)–winter wheat. At the 0–1.20 m depth, STC was 14–20 Mg C ha–1 greater in GO than MT and TO, but STN was 2.1–2.2 Mg N ha–1 greater in TO than GO and MT. The NH4+-N and NO3–-N contents were 5–21 kg N ha–1 greater in MT than GO and TO. While STC and STN tended to increase with year for all treatments, NH4+-N and NO3–-N contents varied with treatments and years. Sheep grazing enhanced soil C storage, but had a variable effect on N storage and residual N compared to tillage and herbicide application for weed control.
Edge effects created by fenced conservation reserves benefit an invasive mesopredator
Authors: McGregor Hugh , Read John , Johnson Christopher N. , Legge Sarah , Hill Brydie , Moseby Katherine
Published: July 2020

Abstract
ContextFenced reserves from which invasive predators are removed are increasingly used as a conservation management tool, because they provide safe havens for susceptible threatened species, and create dense populations of native wildlife that could act as a source population for recolonising the surrounding landscape. However, the latter effect might also act as a food source, and promote high densities of invasive predators on the edges of such reserves.
AimsOur study aimed to determine whether activity of the feral cat is greater around the edges of a fenced conservation reserve, Arid Recovery, in northern South Australia. This reserve has abundant native rodents that move through the fence into the surrounding landscape.
MethodsWe investigated (1) whether feral cats were increasingly likely to be detected on track transects closer to the fence over time as populations of native rodents increased inside the reserve, (2) whether native rodents were more likely to be found in the stomachs of cats caught close to the reserve edge, and (3) whether individual cats selectively hunted on the reserve fence compared with two other similar fences, on the basis of GPS movement data.
Key resultsWe found that (1) detection rates of feral cats on the edges of a fenced reserve increased through time as populations of native rodents increased inside the reserve, (2) native rodents were far more likely to be found in the stomach of cats collected at the reserve edge than in the stomachs of cats far from the reserve edge, and (3) GPS tracking of cat movements showed a selection for the reserve fence edge, but not for similar fences away from the reserve.
ConclusionsInvasive predators such as feral cats are able to focus their movements and activity to where prey availability is greatest, including the edges of fenced conservation reserves. This limits the capacity of reserves to function as source areas from which animals can recolonise the surrounding landscape, and increases predation pressure on populations of other species living on the reserve edge.
ImplicationsManagers of fenced conservation reserves should be aware that increased predator control may be critical for offsetting the elevated impacts of feral cats attracted to the reserve fence.
A constraint-based modeling of negative polarity items in result clause constructions in Romanian
Authors: Rizea Monica-Mihaela , Sailer Manfred
Published: July 2020

The paper discusses the occurrence of emphatic negative polarity items (NPIs) in high degree result clause constructions. We will identify four distributional patterns for Romanian emphatic NPIs. These will range from NPIs that only occur occasionally in result constructions to NPIs that are bound to such constructions and even do not show any truth-conditionally relevant semantic contribution. We reformulate a scalar, pragmatic theory of NPIs in a constraint-based, representational framework,Lexical Resource Semantics. We propose a scalar extension of a standard semantics of result clauses in order to capture the high degree, i.e. intensification readings. The constraint-based, representational perspective of this paper allows for an elegant modeling of the data: (i) We can capture the four distributional patterns as a lexical property of the discussed NPIs. (ii) The semantics and pragmatics of Romanian result clause constructions is accounted for by lexical properties of the result clause complementizers. (iii) A scalar analysis of emphatic NPIs can be applied in embedded clauses and even when the NPI itself does not contribute to the at-issue content of the overall utterance.
Preparing for tenure & promotion
Authors: Geeslin Kimberly L. , Gurzynski-Weiss Laura
Published: July 2020

The present chapter addresses the core issues related to the
process of securing tenure with the primary goal of identifying the sources
of confusion and making transparent some of the unspoken expectations that
tend to dominate the field of applied linguistics. It is our belief that the
better one understands the process the more likely one is able to manage the
anxiety and demands associated with tenure-track positions, and even enjoy
these years. We begin with the idea that there are certain behaviors that
can be useful during the entire pre-tenure process (and beyond!) and that
there is a certain chronology as well: starting off right, preparing for the
mid-term review and then, putting on those final touches as you near the
dossier submission stage. We close with a brief discussion of perspective
and highlight behaviors that make successful academics throughout the career
trajectory.
Emergent gravity from off-shell energy fixing
Authors: de Anda Francisco J
Published: July 2020

Off-shell processes do not preserve the energy momentum tensor (EMT) in quantum field theory (QFT). Fixing the EMT throughout off-shell processes, implies a graviton-like quantum field to emerge without dynamics. Its dynamics are generated through quantum corrections. This fixed off-shell energy condition (FOSEC) implies the existence of a linear gravity-like theory, and in special cases the full Poincarè gauge theory. In this work it is shown that imposing the FOSEC in QFT implies the emergence of a viable quantum theory of gravity.
Phonon spectra of pure and acceptor doped BaZrO3 investigated with visible and UV Raman spectroscopy
Authors: Mazzei Laura , Rukser Dieter , Biebl Florian , Grimm-Lebsanft Benjamin , Neuber Gerd , Pergolesi Daniele , Börjesson Lars , Rübhausen Michael A , Andreasson Jakob , Karlsson Maths
Published: July 2020

We report results from visible and UV Raman spectroscopy studies of the phonon spectra of a polycrystalline sample of the prototypical perovskite type oxide BaZrO3 and a 500 nm thick film of its Y-doped, proton conducting, counterpart BaZr0.8Y0.2O2.9. Analysis of the Raman spectra measured using different excitation energies (between 3.44 eV and 5.17 eV) reveals the activation of strong resonance Raman effects involving all lattice vibrational modes. Specifically, two characteristic energies were identified for BaZrO3, one around 5 eV and one at higher energy, respectively, and one for BaZr0.8Y0.2O2.9, above 5 eV. Apart from the large difference in spectral intensity between the non-resonant and resonant conditions, the spectra are overall similar to each other, suggesting that the vibrational spectra of the perovskites are stable when investigated using an UV laser as excitation source. These results encourage further use of UV Raman spectroscopy as a novel approach for the study of lattice vibrational dynamics and local structure in proton conducting perovskites, and open up for, e.g., time-resolved experiments on thin films targeted at understanding the role of lattice vibrations in proton transport in these kinds of materials.
Large time behavior for a compressible two-fluid model with algebraic pressure closure and large initial data
Authors: Li Yang , Sun Yongzhong , Zatorska Ewelina
Published: July 2020

In this paper, we consider a compressible two-fluid system with a common velocity field and algebraic pressure closure in dimension one. Existence, uniqueness and stability of global weak solutions to this system are obtained with arbitrarily large initial data. Making use of the uniform-in-time bounds for the densities from above and below, exponential decay of weak solution to the unique steady state is obtained without any smallness restriction to the size of the initial data. In particular, our results show that degeneration to single-fluid motion will not occur as long as in the initial distribution both components are present at every point.
Hydrogenic entanglement
Authors: Qvarfort Sofia , Bose Sougato , Serafini Alessio
Published: July 2020

Is there any entanglement in the simplest ubiquitous bound system? We study the solutions to the time-independent Schrödinger equation for a hydrogenic system and devise two entanglement tests for free and localised states. For free hydrogenic systems, we compute the Schmidt basis diagonalisation for general energy eigenstates, and for a hydrogenic system localised to a three-dimensional Gaussian wavepacket, we demonstrate that measuring its second moments is sufficient for detecting entanglement. Our results apply to any system that exhibits hydrogenic structure.
Deuterium release from deuterium plasma-exposed neutron-irradiated and non-neutron-irradiated tungsten samples during annealing
Authors: Alimov V.Kh. , Hatano Y. , Kuwabara T. , Toyama T. , Someya Y. , Spitsyn A.V.
Published: July 2020

We examine the effect of neutron irradiation on the release of deuterium from tungsten at 573 K to understand the efficiency of tritium removal by baking out at moderate temperatures. Tungsten samples, undamaged and neutron-irradiated to a damage level of approximately 0.016 displacements per atom, are exposed to low-energy (108 eV), high-flux (3.0 × 1021 to 9.4 × 1021 m−2 s−1) deuterium plasma at temperatures ranging from 573 to 773 K to an ion fluence of 1.1 × 1025 m−2. At each exposure temperature, two undamaged and two neutron-irradiated tungsten samples are exposed to plasma. The deuterium content in the tungsten samples is measured by thermal desorption spectrometry soon after the plasma exposure and after post-plasma annealing at 573 K for 30 h. It is found that: (i) the deuterium retention in the neutron-irradiated tungsten samples is significantly higher than that in the undamaged tungsten samples; (ii) annealing at 573 K of undamaged tungsten samples pre-exposed to deuterium plasma at 573–773 K leads to an almost complete (60%–99%) release of deuterium from the samples; (iii) annealing at 573 K of neutron-irradiated tungsten samples pre-exposed to deuterium plasma at 573–773 K leads to a significant (8%–20%) release of deuterium from the samples.
Learning performance in inverse Ising problems with sparse teacher couplings
Authors: Abbara Alia , Kabashima Yoshiyuki , Obuchi Tomoyuki , Xu Yingying
Published: July 2020

We investigate the learning performance of the pseudolikelihood maximization method for inverse Ising problems. In the teacher–student scenario under the assumption that the teacher’s couplings are sparse and the student does not know the graphical structure, the learning curve and order parameters are assessed in the typical case using the replica and cavity methods from statistical mechanics. Our formulation is also applicable to a certain class of cost functions having locality; the standard likelihood does not belong to that class. The derived analytical formulas indicate that the perfect inference of the presence/absence of the teacher’s couplings is possible in the thermodynamic limit taking the number of spins N as infinity while keeping the dataset size M proportional to N, as long as α = M/N > 2. Meanwhile, the formulas also show that the estimated coupling values corresponding to the truly existing ones in the teacher tend to be overestimated in the absolute value, manifesting the presence of estimation bias. These results are considered to be exact in the thermodynamic limit on locally tree-like networks, such as the regular random or Erdős–Rényi graphs. Numerical simulation results fully support the theoretical predictions. Additional biases in the estimators on loopy graphs are also discussed.
Retracted: Study on tensile, bending, fatigue, and in vivo behavior of porous SHS–TiNi alloy used as a bone substitute
Authors: Yasenchuk Yuri , Marchenko Ekaterina , Baigonakova Gulsharat , Gunther Sergey , Kokorev Oleg , Gunter Victor , Chekalkin Timofey , Topolnitskiy Evgeniy , Obrosov Aleksei , Kang Ji-hoon
Published: July 2020

Intermetallic porous SHS–TiNi alloys exhibit tangled and specific stress–strain characteristics. This article aims to evaluate the findings emanating from experiments using standard and proprietary instruments. Fatigue testing under repeated complex loading was used to measure the total number of load cycles before failure of the SHS–TiNi samples occurred. Of the tested samples, seventy percent passed through 106 cycles without failure due to the reversible martensite transformation in the TiNi phase, one of the prevailing constituents of a multiphase matrix. The fractured surfaces were analyzed using scanning electron microscopy and confocal laser scanning instruments. Microscopy studies showed that the entire surface of the sample is concealed by miscellaneous strata that result from the SHS processand effectively protect the porous alloy in a corrosive environment. Numerous non-metallic inclusions, which are also attributed to the SHS reaction, do not have a significant impact on the deformation behavior and fatigue performance. In this context, the successful in vivo functioning of porous grafts assessed in a canine rib-plasty model allows the bone substitute to be congruentially deformed in the body without rejection or degradation; it thus has a long operational life, often greater than 17 ×106 (22 × 60 × 24 × 540) cycles. It acknowledges the potential benefits of SHS–TiNi as a superior osteoplastic material and its high resistance to corrosion fatigue.
Functional and cognitive decline in older delirious adults after an emergency department visit
Authors: Giroux Marianne , Émond Marcel , Nadeau Alexandra , Boucher Valérie , Carmichael Pierre-Hugues , Voyer Philippe , Pelletier Mathieu , Gouin Émilie , Daoust Raoul , Berthelot Simon , Lamontagne Marie-Eve , Morin Michèle , Lemire Stéphane , Sirois Marie-Josée
Published: July 2020

Background

the aim of this study was to evaluate the impact of emergency department (ED) stay-associated delirium on older patient’s functional and cognitive status at 60 days post ED visit.

Methods

this study was part of the multi-centre prospective cohort INDEED study. This project took place between March 2015 and July 2016 in five participating EDs across the province of Quebec. Independent non-delirious patients aged ≥65, with an ED stay ≥8 hours, were monitored for delirium until 24 hours post ward admission. A 60-day follow-up phone assessment was conducted. Participants were screened for delirium using the Confusion Assessment Method. Functional and cognitive statuses were assessed at baseline and at the 60-day follow-up using OARS and TICS-m.

Results

a total of 608 patients were recruited, 393 of which completed the 60-day follow-up. The Confusion Assessment Method was positive in 69 patients (11.8%) during ED stay or within the first 24 hours following ward admission. At 60 days, delirium patients experienced an adjusted loss of −2.9/28 [95%CI: −3.9, −2.0] points on the OARS scale compared to non-delirious patients who lost −1.6 [95%CI: −1.9, −1.3] (P = 0.006). A significant adjusted difference in cognitive function was also noted at 60 days, as TICS-m scores in delirious patients decreased by −1.6 [95%CI: −3.5, 0.2] compared to non-delirious patients, who showed a minor improvement of 0.5 [95%CI: −0.1, 1.1] (P = 0.03).

Conclusion

seniors who developed ED stay-associated delirium have lower baseline functional and cognitive status than non-delirious patients, and they will experience a more significant decline at 60 days post ED visit.
SARS-CoV-2 Infection–Associated Hemophagocytic Lymphohistiocytosis
Authors: Prilutskiy Andrey , Kritselis Michael , Shevtsov Artem , Yambayev Ilyas , Vadlamudi Charitha , Zhao Qing , Kataria Yachana , Sarosiek Shayna R , Lerner Adam , Sloan J Mark , Quillen Karen , Burks Eric J
Published: July 2020

Objectives

A subset of coronavirus disease 2019 (COVID-19) patients exhibit clinical features of cytokine storm. However, clinicopathologic features diagnostic of hemophagocytic lymphohistiocytosis (HLH) have not been reported. We studied the reticuloendothelial organs of 4 consecutive patients who died of COVID-19 and correlated with clinical and laboratory parameters to detect HLH.

Methods

Autopsies were performed on 4 patients who died of COVID-19. Routine H&E staining and immunohistochemical staining for CD163 were performed to detect hemophagocytosis. Clinical and laboratory results from premortem blood samples were used to calculate H-scores.

Results

All 4 cases demonstrated diffuse alveolar damage within the lungs. Three of the 4 cases had histologic evidence of hemophagocytosis within pulmonary lymph nodes. One case showed hemophagocytosis in the spleen but none showed hemophagocytosis in liver or bone marrow. Lymphophagocytosis was the predominant form of hemophagocytosis observed. One patient showed diagnostic features of HLH with an H-score of 217, while a second patient likely had HLH with a partial H-score of 145 due to a missing triglyceride level. The remaining 2 patients had H-scores of 131 and 96.

Conclusions

This is the first report of severe acute respiratory syndrome coronavirus 2–associated HLH. Identification of HLH in a subset of patients with severe COVID-19 will inform clinical trials of therapeutic strategies.
The Role of Ultrasound-Guided Fine-Needle Aspiration of Thyroid Bed Lesions and Clinical Predictors of Recurrent Papillary Thyroid Carcinoma
Authors: Yuan Lisi , Jebastin Thangaiah Judith , Chute Deborah J
Published: July 2020

Objectives

Fine-needle aspiration (FNA) of thyroid bed lesions after thyroidectomy is challenging to evaluate. We determined the sensitivity, specificity, and positive and negative predicative value of thyroid bed FNA (TB-FNA) for detecting local recurrence of thyroid carcinoma.

Methods

A retrospective search was conducted for TB-FNAs from patients with a prior thyroid resection and subsequent ipsilateral FNA from the thyroid bed. Clinical and pathologic data were retrieved from the medical record. Patients were ultimately classified as “malignant” or “benign” based on the worst pathology identified and follow-up available.

Results

Forty-two cases were included, and the prior thyroidectomy pathology included 36 papillary thyroid carcinomas, two follicular carcinomas, one medullary carcinoma, and three benign cases. TB-FNA was adequate in 38 (90.5%) cases and interpreted as positive for malignancy (n = 22; 52.4%), suspicious for follicular neoplasm (n = 3; 7.1%), atypia of unknown significance (n = 2; 4.8%), and benign (n = 10; 23.8%). Twenty-seven patients had histologic follow-up, and 24 (87.5%) showed recurrent malignancy. The cytology sensitivity, specificity, positive predictive value, negative predictive value, and accuracy were 96%, 100%, 100%, 92.3%, and 97.4%, respectively, for identification of recurrent malignancy.

Conclusions

Most TB-FNA cases ultimately were diagnosed with malignancy on follow-up, although there may be sampling bias, as not all clinically benign cases had surgical follow-up.