bluuebunny/crossref_metadata_2025 huggingface dataset:
Three-dimensional effect of particle motion on plasma filament dynamics
Authors: Hasegawa Hiroki , Ishiguro Seiji
Published: June 2019

It is shown for the first time with the three-dimensional (3D) electrostatic particle-in-cell simulation that the plasma particle motion influences plasma filament dynamics three-dimensionally. If we assume that the filament size on the cross section is a few times as large as ρemi/me and that the ion temperature is higher than the electron temperature, the poloidal symmetry of filament propagation is broken and the propagation velocity has the non-negligible poloidal component, where ρe is the electron Larmor radius. Then, it is observed that such propagation dynamics depend on the position on the magnetic field line, i.e., in the toroidal direction. As the ion temperature increases beyond the electron temperature, the perpendicular electric field in a filament varies greatly according to the toroidal position. Such a variation might arise from the presheath potential drop on the potential hill side in a filament. Thus, the toroidal dependence of the propagation dynamics appears.
Shock-driven hydrodynamic instability of a sinusoidally perturbed, high-Atwood number, oblique interface
Authors: Rasmus A. M. , Di Stefano C. A. , Flippo K. A. , Doss F. W. , Kawaguchi C. F. , Kline J. L. , Merritt E. C. , Desjardins T. R. , Cardenas T. , Schmidt D. W. , Donovan P. M. , Fierro F. , Goodwin L. A. , Martinez J. I. , Quintana T. E. , Zingale J. S. , Kuranz C. C.
Published: June 2019

A shock incident on an interface will cause any initial perturbations on that interface to grow. When the shock front is parallel to the interface, the perturbations grow due to the Richtmyer-Meshkov (RM) process. When there is some tilt between the shock front and the interface, shear flow will result across the postshock interface. Recent experiments on the OMEGA EP laser have studied the hydrodynamic instability growth which results from a supported shock interacting with a sinusoidally perturbed, oblique interface. The observed instability growth was dominated by Richtmyer-Meshkov at early times but became Kelvin-Helmholtz (KH)-like at late times. Previously, this instability growth was described using an analytic model for the deposition of baroclinic vorticity on the interface by a shock combined with a discrete vortex model. Here, we utilize the same baroclinic vorticity deposition model in conjunction with a desingularized, periodic Birkhoff-Rott equation to model instability evolution. The Birkhoff-Rott equation takes into account the vorticity distribution along the interface, whereas the discrete vortex model assumed that all vorticity over each wavelength of the perturbation is confined to a point. We compare the new model to xRAGE simulations and experiments. The model is found to overpredict both the instability growth and shear across the interface by about a factor of two, but correctly predicts that the growth is RM-like at early times and KH-like at late times.
Lattice resonances in dielectric metasurfaces
Authors: Castellanos Gabriel W. , Bai Ping , Gómez Rivas Jaime
Published: June 2019

We present a numerical investigation of collective resonances in lattices of dielectric nanoparticles. These resonances emerge from the enhanced radiative coupling of localized Mie resonances in the individual nanoparticles. We distinguish two similar systems: a lattice of silicon nanoparticles homogeneously embedded in a dielectric and a lattice of silicon nanoparticles in an optical waveguide. The radiative coupling is provided by diffraction orders in the plane of the array for the former system or by guided modes in the optical waveguide for the latter one. The different coupling leads to distinct lattice resonances in the metasurface defined by the array of silicon nanoparticles. These resonances have been extensively investigated in metallic nanoparticle arrays, but remain highly unexplored in fully dielectric systems. We describe the pronounced differences in the intensity enhancement and field distributions for the two systems, providing valuable information for the design and optimization of optical components based on dielectric lattice resonances.
Directed adaptation of synchronization levels in oscillator communities
Authors: Fengler Enrico , Totz Jan Frederik , Kaluza Pablo , Engel Harald
Published: June 2019

We present an adaptive control scheme that realizes desired dynamics of an oscillator network with a given number of communities by adjusting the coupling weights between oscillators accordingly. The scheme allows, for example, to simultaneously establish different pregiven synchronization levels in the particular communities as well as phase relationships between them. We apply the method in numerical simulations with all-to-all and randomly coupled networks. Moreover, we provide an experimental proof of concept validating our numerical findings in a network of optically coupled photosensitive chemical micro-oscillators.
Photoconductive terahertz detectors with 105 dB peak dynamic range made of rhodium doped InGaAs
Authors: Kohlhaas R. B. , Breuer S. , Nellen S. , Liebermeister L. , Schell M. , Semtsiv M. P. , Masselink W. T. , Globisch B.
Published: June 2019

Rhodium (Rh)-doped In0.53Ga0.47As grown by gas-source molecular beam epitaxy is investigated as a terahertz (THz) detector antenna for optical excitation at 1550 nm. The 4d transition metal rhodium acts as a deep level and ultrafast trapping center. At a doping concentration around 8 × 1019 cm−3, InGaAs:Rh exhibits ideal properties for application as a THz antenna: an ultrashort carrier lifetime below 200 fs in combination with a mobility of 1010 cm2/Vs. The THz detectors fabricated from this sample show a record peak dynamic range of 105 dB and a bandwidth of up to 6.5 THz.
Enhanced ferroelectricity in epitaxial Hf0.5Zr0.5O2 thin films integrated with Si(001) using SrTiO3 templates
Authors: Lyu J. , Fina I. , Bachelet R. , Saint-Girons G. , Estandía S. , Gázquez J. , Fontcuberta J. , Sánchez F.
Published: June 2019

SrTiO3 templates have been used to integrate epitaxial bilayers of ferroelectric Hf0.5Zr0.5O2 and La2/3Sr1/3MnO3 bottom electrodes on Si(001). The Hf0.5Zr0.5O2 films show enhanced properties in comparison to equivalent films on SrTiO3(001) single crystalline substrates. The films, thinner than 10 nm, have a very high remnant polarization of 34 μC/cm2. Hf0.5Zr0.5O2 capacitors at an operating voltage of 4 V present a long retention time well beyond 10 years and high endurance against fatigue up to 109 cycles. The robust ferroelectric properties displayed by the epitaxial Hf0.5Zr0.5O2 films on Si(001) using SrTiO3 templates pave the way for the monolithic integration on silicon of emerging memory devices based on epitaxial HfO2.
Exhaustive state-to-state cross sections for reactive molecular collisions from importance sampling simulation and a neural network representation
Authors: Koner Debasish , Unke Oliver T. , Boe Kyle , Bemish Raymond J. , Meuwly Markus
Published: June 2019

High-temperature, reactive gas flow is inherently nonequilibrium in terms of energy and state population distributions. Modeling such conditions is challenging even for the smallest molecular systems due to the extremely large number of accessible states and transitions between them. Here, neural networks (NNs) trained on explicitly simulated data are constructed and shown to provide quantitatively realistic descriptions which can be used in mesoscale simulation approaches such as Direct Simulation Monte Carlo to model gas flow at the hypersonic regime. As an example, the state-to-state cross sections for N(4S) + NO(2Π) → O(3P) + N2(X1Σg+) are computed from quasiclassical trajectory (QCT) simulations. By training NNs on a sparsely sampled noisy set of state-to-state cross sections, it is demonstrated that independently generated reference data are predicted with high accuracy. State-specific and total reaction rates as a function of temperature from the NN are in quantitative agreement with explicit QCT simulations and confirm earlier simulations, and the final state distributions of the vibrational and rotational energies agree as well. Thus, NNs trained on physical reference data can provide a viable alternative to computationally demanding explicit evaluation of the microscopic information at run time. This will considerably advance the ability to realistically model nonequilibrium ensembles for network-based simulations.
Probing micron-scale distributed contortions via a twisted multicore optical fiber
Authors: Ahmad Raja , Westbrook Paul S. , Ko Wing , Feder Kenneth S.
Published: June 2019

Continuous measurement of small length scale contortions along an arbitrary path is a highly relevant goal within many branches of engineering and technology. An optical fiber—where the probing light propagates within a confined and shielded region—presents an ideal platform for developing the distributed contortion-sensors. In the past, significant progress has been made in developing optical fiber sensors, but a robust and high-resolution distributed contortion-sensor has not been reported in detail. Here, we report the first distributed measurements of fiber contortions with an ultrahigh sensitivity—≤0.3 μm in the transverse plane, 40 μm longitudinal spatial step size, and ≤8 μm resolution for periodic contortions in the longitudinal plane—via a Bragg-grating-inscribed twisted multicore optical fiber. The results are in excellent agreement with the predictions from the Euler-Bernoulli beam-bending model that relates the applied force with the fiber microcontortions. Our distributed-sensor holds promise for a widespread application within a diverse range of fields including biotechnology, robotics, transportation, geology, and security.
The Wendlands of Herrenhausen Gardens (Hanover, Germany): a study of their Australian plant specimens in the herbarium of the University of Goettingen (GOET)
Authors: Dowe J. L. , Reiner-Drehwald M. E. , Appelhans M. S. , Hörandl E.
Published: June 2019

Between 1778 and 1903, three successive generations of the Wendland family were Court Gardeners at the Royal Gardens of Herrenhausen, Hanover, Germany. In addition to their horticultural responsibilities, they published several important taxonomic accounts, some involving Australian plants. Johann Christoph Wendland (1755–1828) (J.C.Wendl.) established the endemic Australian genera Angianthus J.C.Wendl. (Asteraceae), Hakea Schrad. & J.C.Wendl. (Proteaceae) and Waitzia J.C.Wendl. (Asteraceae), and provided novel work on Melaleuca L. (Myrtaceae) and Acacia Mill. (as Mimosa L; Fabaceae); Heinrich Ludolph Wendland (1792–1869) (H. L.Wendl.) provided novel and revisionary work on Acacia and Leptospermum J.R.Forst. & G.Forst. (Myrtaceae); and Hermann Wendland (1825–1903) (H. Wendl.) specialised in the palms (Arecaceae) and wrote Palmae Australasicae with Oscar Drude, the foundational work on Australian palms. A search of all the databases and other references accessible to us has resulted in the identification of ~148 names of Australian plants in which the author citation includes any of the three Wendlands. Of these, ~30 are the currently accepted names. Lectotypes are here proposed for the names Acacia amoena H.L.Wendl., A. crassiuscula H.L.Wendl., A. dolabriformis H.L.Wendl., A. emarginata H.L.Wendl., A. homomalla H.L.Wendl., Aster tomentosus J.C.Wendl., Leptospermum buxifolium H.L.Wendl., L. emarginatum H.L.Wendl. ex Link, L. glomeratum H.L.Wendl., Melaleuca linearis Schrad. & J.C.Wendl., M. thea Schrad. & J.C.Wendl., Passiflora glabra J.C.Wendl., Protea nectarina J.C.Wendl., P. pulchella Schrad. & J.C.Wendl., Pultenaea daphnoides J.C.Wendl., P. linophylla Schrad. & J.C.Wendl., P. retorta J.C.Wendl. and Tristania subverticillata H.L.Wendl. Figures are provided of all the proposed lectotypes housed in GOET.
Morphological and molecular data show an enlarged tropical Australian radiation in Synostemon (Phyllanthaceae, Phyllantheae) previously concealed by heteromorphic species concepts
Authors: Telford Ian R. H. , Pruesapan Kanchana , van Welzen Peter C. , Bruhl Jeremy J.
Published: June 2019

Sauropus elachophyllus (F.Muell. ex Benth.) Airy Shaw and S. rigidulus (F.Muell. ex Müll.Arg.) Airy Shaw are revised under the reinstated genus Synostemon F.Muell. (Phyllanthaceae) using morphological and nrITS sequence data. Sauropus decrescentifolius J.T.Hunter & J.J.Bruhl and S. elachophyllus are shown to be conspecific as Synostemon elachophyllus (F.Muell. ex Benth.) I.Telford & Pruesapan and S. elachophyllus subsp. decrescentifolius (J.T.Hunter & J.J.Bruhl) I.Telford & Pruesapan, with Synostemon elachophyllus subsp. latior (Airy Shaw) I.Telford & Pruesapan (syn. Sauropus elachophyllus var. glaber Airy Shaw p.p.) raised in rank. The ‘Top End clade’ has morphological synapomorphies of fused staminal filaments and connectives, and linear, longitudinal anthers. Four new species are named: Synostemon cowiei I.Telford & J.J.Bruhl, S. inaequisepalus I.Telford & J.J.Bruhl, S. kakadu I.Telford & J.J.Bruhl and S. nitmiluk I.Telford & J.J.Bruhl and new combinations are provided: S. crassifolius (Müll.Arg.) I.Telford & Pruesapan, S. ditassoides (Müll.Arg.) I.Telford & Pruesapan, S. dunlopii (J.T.Hunter & J.J.Bruhl) I.Telford & Pruesapan, S. filicinus (J.T.Hunter & J.J.Bruhl) I.Telford & Pruesapan, S. gracilis (J.T.Hunter & J.J.Bruhl) I.Telford & Pruesapan, S. rigidulus (F.Muell. ex Müll.Arg.) I.Telford & Pruesapan, and S. stenocladus (S.Moore) I.Telford & Pruesapan, with S. pinifolius (J.T.Hunter & J.J.Bruhl) I.Telford & Pruesapan also raised in rank.
Monthly adaptations of the Drought Code reveal nuanced fire–drought associations in montane forests with a mixed-severity fire regime
Authors: Chavardès Raphaël D. , Daniels Lori D. , Eskelson Bianca N. I. , Pickell Paul D.
Published: June 2019

We compared three monthly adaptations of the daily Drought Code (DC) of Canada’s Fire Weather Index System and applied them to interpret drought conditions associated with historical fires in montane forests of south-eastern British Columbia. The three adaptations were compared with the monthly mean DC calculated from daily values for the Palliser fire-weather station. Two adaptations improved on the existing Monthly DC calculated from monthly climate data by (1) accounting for overwinter drying and an early start to the fire season, and (2) improving estimates of effective precipitation. Using a cross-dated fire-scar record from 20 sites in montane forests surrounding the Palliser station, we found significant fire–drought associations from June to August with all adaptations, and significant associations in April and May with the two new adaptations. Of the 17 fire years from 1901 to 2013, 6years had low initial drought conditions that increased late in the fire season, and 5 years had high drought conditions throughout the fire season. We conclude that variable drought within and among fire seasons influenced fire severity. Our findings provide a connection between modern drought indices used to rank fire danger and drought effects on the historical mixed-severity fire regime in montane forests of south-eastern British Columbia.
Evaluating ecological resilience across wildfire suppression levels under climate and fuel treatment scenarios using landscape simulation modelling
Authors: Keane Robert E. , Gray Kathy , Davis Brett , Holsinger Lisa M. , Loehman Rachel
Published: June 2019

Continued suppression of wildfires may allow more biomass to accumulate to foster even more intense fires. Enlightened fire management involves explicitly determining concurrent levels of suppression, wildland fire use (allowing some fires to burn) and fuel treatments to manage landscapes for ecological resilience. This study used the mechanistic landscape model FireBGCv2 to simulate ecological dynamics on three landscapes in the US northern Rocky Mountains to determine responses of seven management-oriented variables over a gradient of 10 fire suppression levels under two climate and four fuel treatment scenarios. We used a historical range and variation (HRV) time series of the seven variables individually and merged together as a Principal Components factor (PC1) to define the envelope that represents ecological resiliency and compared all simulations with the HRV base case. We found that under today’s climates, using the PC1 factor, ecological resilience was maintained while suppressing 30–90% of wildfires depending on the landscape. We also found fuel treatments might allow higher suppression levels to occur and still maintain resilience. Other findings indicate that each landscape must be individually evaluated to determine the right mix of wildfires, wildland fire use and fuel treatments depending on the response variables used to evaluate resilience.
Occupancy and abundance of free-roaming cats in a fragmented agricultural ecosystem
Authors: Webster Sarah C. , Olson Zachary H. , Beasley James C.
Published: June 2019

Context Free-roaming domestic cats are a widespread invasive species, occurring throughout the globe in urban and rural environments alike. However, robust estimates of cat occupancy and abundance, especially in rural, agricultural landscapes, are largely unknown. Aims To estimate cat occupancy and abundance within forested habitat in a fragmented agricultural region of Indiana, USA. Methods Free-roaming cats in 55 forest patches were captured from 2004 to 2010 to assess the effects of landscape attributes on cat occupancy probabilities. During 2009–10 abundance of cats in each habitat patch was estimated based on natural markings of captured individuals. Key results Across the entire study (2004–10) cats in 50 of the 55 patches were detected, but detections varied temporally and spatially. Average occupancy probability was estimated at Ψ = 0.773 (s.e. = 0.109), and detection probability was estimated as P = 0.204 (s.e. = 0.012). Distance to human structures and forest patch isolation both were found to negatively influence cat occupancy. In total, 57 individual cats were captured in 2009 and 55 in 2010, when unique individuals were distinguished. Across all forest patches, average cat abundance was n = 1.08 in 2009 and n = 0.91 in 2010, ranging from 0 to 7 among sampled patches. Conclusions Overall, the distribution of free-roaming cats across a rural agricultural landscape varied temporally and was associated with proximity to human structures and the proximity of other forest habitat. Similarly, abundance was found to vary spatially and temporally. Implications The findings suggest free-roaming cats are widespread throughout agricultural ecosystems, but their distribution is dynamic and non-random. Additionally, the potential for cats to impact native fauna inhabiting remnant forest patches is high in fragmented agricultural ecosystems due to the concentration of native species utilising these patches. Further research is needed to determine the effects free-roaming cats are having on native species in human-dominated, rural ecosystems, and what conservation measures might be implemented to best mitigate any impacts.
Elephants have a nose for quantity
Authors: Plotnik Joshua M. , Brubaker Daniel L. , Dale Rachel , Tiller Lydia N. , Mumby Hannah S. , Clayton Nicola S.
Published: June 2019

Significance

Although many animal species have demonstrated an ability to differentiate between more and less when presented with different amounts of food, they have done so primarily using vision. In this study, by contrast, elephants showed that they can detect differences between various quantities of food using only their sense of smell. Thus, elephants may be unique in their use of olfaction in cognitive tasks. This research suggests that it is important for psychologists to incorporate into experimental designs the ways in which different animals interact with their environment using all of their senses. Such species-specific paradigms would ensure comparisons about cognition across taxa are fair and relevant.
Earliest known Oldowan artifacts at >2.58 Ma from Ledi-Geraru, Ethiopia, highlight early technological diversity
Authors: Braun David R. , Aldeias Vera , Archer Will , Arrowsmith J Ramon , Baraki Niguss , Campisano Christopher J. , Deino Alan L. , DiMaggio Erin N. , Dupont-Nivet Guillaume , Engda Blade , Feary David A. , Garello Dominique I. , Kerfelew Zenash , McPherron Shannon P. , Patterson David B. , Reeves Jonathan S. , Thompson Jessica C. , Reed Kaye E.
Published: June 2019

Significance

Humans are distinguished from all other primates by their reliance on tool use. When this uniquely human feature began is debated. Evidence of tool use in human ancestors now extends almost 3.3 Ma and becomes prevalent only after 2.6 Ma with the Oldowan. Here, we report a new Oldowan locality (BD 1) that dates prior to 2.6 Ma. These earliest Oldowan tools are distinctive from the 3.3 Ma assemblage and from materials that modern nonhuman primates produce. So, although tool production and use represent a generalized trait of many primates, including human ancestors, the production of Oldowan stone artifacts appears to mark a systematic shift in tool manufacture that occurs at a time of major environmental changes.
Evidence for a vestigial nematic state in the cuprate pseudogap phase
Authors: Mukhopadhyay Sourin , Sharma Rahul , Kim Chung Koo , Edkins Stephen D. , Hamidian Mohammad H. , Eisaki Hiroshi , Uchida Shin-ichi , Kim Eun-Ah , Lawler Michael J. , Mackenzie Andrew P. , Davis J. C. Séamus , Fujita Kazuhiro
Published: June 2019

Significance

In the cuprate pseudogap phase, an energy gap of unknown mechanism opens, and both an electronic nematic phase (NE) and a density-wave (DW) phase appear. Perplexingly, the DW, which should generate an energy gap, appears without any new gap opening; and the NE, which should be incapable of opening an energy gap, emerges coincident with the pseudogap opening. Recently, however, it was demonstrated theoretically that a disordered unidirectional DW can generate a vestigial nematic (VN) phase. If the cuprate pseudogap phase were in such a VN state, the energy gap of the NE and DW should be identical to each other and to the pseudogap. We report discovery of such a phenomenology throughout the phase diagram of underdoped Bi
2
Sr
2
CaCu
2
O
8
.
Influence of single-nanoparticle electrochromic dynamics on the durability and speed of smart windows
Authors: Evans R. Colby , Ellingworth Austin , Cashen Christina J. , Weinberger Christopher R. , Sambur Justin B.
Published: June 2019

Nanomaterials have tremendous potential to increase electrochromic smart window efficiency, speed, and durability. However, nanoparticles vary in size, shape, and surface defects, and it is unknown how nanoparticle heterogeneity contributes to particle-dependent electrochromic properties. Here, we use single-nanoparticle-level electro-optical imaging to measure structure–function relationships in electrochromic tungsten oxide nanorods. Single nanorods exhibit a particle-dependent waiting time for tinting (from 100 ms to 10 s) due to Li-ion insertion at optically inactive surface sites. Longer nanorods tint darker than shorter nanorods and exhibit a Li-ion gradient that increases from the nanorod ends to the middle. The particle-dependent ion-insertion kinetics contribute to variable tinting rates and magnitudes across large-area smart windows. Next, we quantified how particle–particle interactions impact tinting dynamics and reversibility as the nanorod building blocks are assembled into a thin film. Interestingly, single particles tint 4 times faster and cycle 20 times more reversibly than thin films made of the same particles. These findings allow us to propose a nanostructured electrode architecture that optimizes optical modulation rates and reversibility across large-area smart windows.
Fast-moving bat ears create informative Doppler shifts
Authors: Yin Xiaoyan , Müller Rolf
Published: June 2019

Significance

Many animal species are known for unparalleled abilities to encode sensory information that supports fast, reliable action in complex environments, but the mechanisms remain often unclear. Here, we present a nonlinear principle for sensory information encoding in bats. Through fast ear motions, bats can encode information on target direction into time-frequency Doppler signatures. These species were thought to be evolutionarily tuned to Doppler shifts generated by a prey’s wing beat. Self-generated Doppler shifts from the bat’s own flight motion were, for the most part, considered a nuisance that the bats compensate for. Our findings indicate that these Doppler-based biosonar systems may be more complicated than previously thought because the animals can actively inject Doppler shifts into their input signals.
Chancery norms before Chancery English?
Authors: Timofeeva Olga
Published: June 2019

This study analyses two Old English formulaegret freodlice(‘greets in a friendly manner’) andic cyðe eow þæt(‘I make it known to you that’), which form a salutation–notification template in a document type calledwrits. It connects the emergence of this formulaic set to previous oral traditions of delivering news and messages, and to their reflection in dictation practices from at least the time of King Alfred. Their later routinisation and standardisation is seen as a factor brought about by the centralised production of royal writs and their subsequent adoption as templates in monastic scriptoria across the country. These templates continue to be recycled in the early Middle English period both in English and in Latin writs, ultimately shifting to Latin-only documents during the reign of William the Conqueror. Although this shift does not hinder the continuity of the selected bureaucratic template into the later Middle Ages, it affects the structure of the discourse community associated with the chancery norms, consolidating its core (those literate in Latin who are involved in production and preservation of writs) and marginalising its periphery (English speakers who used to make up the informed audience for writs in local courts).
Kinship or friendship?
Authors: Häcker Martina
Published: June 2019

The use of the wordcousinas a term of address for non-relatives in late-medieval and Renaissance English is well documented in letters between monarchs, but weak for other social groups in the standard dictionaries, with one example each in theOxford English Dictionaryand theMiddle English Dictionary. As it is difficult to establish for earlier periods whether people were blood relations, an investigation ofcousinas a term of address needs to establish the relationship between addressor and addressee, as far as possible, from independent historical sources. This study is based on the use of the termcousinin letters, as this often provides precise information on the relationships of correspondents. This investigation documents the use ofcousinfrom the thirteenth to the early-sixteenth century in all literate ranks of society and concludes that the royal use ofcousinconstitutes a relic of an earlier more widespread use.
Ecosystem service bundles in global hinterlands
Authors: Haberman Daniel , Bennett Elena M
Published: June 2019

In the face of projected increases in globalization and urbanization, there is growing recognition that cities and their hinterlands will play a pivotal role in both creating and addressing the sustainability challenges of the future. Hinterlands, the rural areas that surround cities, are connected to cities as the source of many of the ecosystem services (ES) that are used in urban areas. While much is known about the provision of multiple ES in and around a few well-studied cities, there is a limited amount of consistently measured, global-scale data about the provision of multiple ES in urban areas and their hinterlands. We mapped eight ES globally, and examined how the production of ES varied between the hinterlands (within 200 km) of 768 major city centers (population > 500 000). We found that there are seven archetypes of ES supply bundles in global hinterlands. Hinterlands near wealthy cities are specialists in regulating ES production while the poorest and most populated hinterlands are specialists in food production, with low levels of regulating and cultural ES provision. These hinterlands also experience different synergies and tradeoffs between ES, with interesting implications for landscape management. Global teleconnections have likely also played a role in the ES bundles of hinterlands, since they have allowed cities to exploit remote areas to meet their demand for ES, undermining the traditional supply-demand relationship between each city and its proximal hinterland. These results emphasize the diverse, and sometimes inequitable, ways that urbanization and globalization are influencing ES supply in the planet’s most human-modified landscapes.
Design and Finite Element Analysis of Ultrasonic Composite Abrasive Vibration Polishing Equipment
Authors: Wan Hongqiang , Han Peiying , Han Quanli , Ge Shuai , Li Fancong
Published: June 2019

In order to develop a workpiece surface polishing equipment with high performance and high precision, the overall structural design and parameter selection of ultrasonic composite abrasive vibration polishing equipment were mainly completed. Secondly, static analysis of the crankshaft connecting rod piston mechanism is performed by ANSYS Workbench software. We can know that the crankshaft connecting rod piston mechanism has the most concentrated stress at the contact between the small end of the connecting rod and the connecting rod shaft. And the stress value is 121.04MPa but less than the allowable stress value of the connecting rod. Therefore, the strength of the crankshaft connecting rod piston mechanism meets the design requirements, and the modal analysis of the crankshaft is carried out, and the crankshaft right crank displacement deformation amount is the most. It provides a theoretical basis for the optimization design of the crankshaft later and provides a reference for the research of ultrasonic composite abrasive vibration polishing equipment.
Effect of Crystal Orientation on Cyclic Plastic Behaviors of Partially Recrystallized Single Crystal Nickel-based Superalloy
Authors: Wei D H , Zhang W J , Huang H Y , Zhang L P , Chen R Y , Wu Y W , Shi H J , Ma X F
Published: June 2019

Surface recrystallization (RX) is one of the main causes of fatigue failure of heavy gas turbine single crystal (SX) blade and thus a threat to safe long-time operation. Using crystal plasticity model, the effects of primary and secondary crystal orientation on the cyclic plastic deformation behaviors of recrystallized SX nickel-based superalloy was investigated via crystal plasticity finite element simulation. The results show that primary orientation has significant effect on the accumulated plastic shear stain γ of the recrystallized SX superalloy: the maximum accumulated plastic shear strain γ
max occurs in SX matrix near RX transverse grain boundary; the maximum accumulated plastic shear strain γ
max of RX-SX system increases with increasing primary orientation(β); the maximum accumulated plastic shear strain γ
max at β=15° is 31.6% larger than that at β=0°; the maximum accumulated plastic shear strain γ
max decreases first and then increases with the increasing of the secondary orientation(θ) from 0° to 90°, with the lowest value of γ
max at θ=43°, which is 1.4% smaller than that at θ=0° and θ=90°. The study shows that the crystal orientation can be optimized to reduce the effect of recrystallized grain on the fatigue property of SX nickel-based superalloy.
Crystal Plasticity Simulation of Hot Deformation Texture of Titanium Alloy Considering Alpha-beta Transformation
Authors: Wei D H , Zhang W J , Zhang L P , Huang H Y , Chen R Y , Wu Y W , Ma X F , Xiong Z H
Published: June 2019

Titanium alloys are usually subjected to hot deformation to optimize its microstructure and mechanical property. In the hot forming process, such as extrusion, texture is of great importance to both manufacturing and performance. In this study, an alpha-beta titanium was used to study the texture evolution during hot extrusion. Large area electronic backscattering scan was used to examine grain orientation distribution. Experimentally measured alpha and beta textures were compared with a rate-dependent crystal plasticity based simulation. The model is capable of predicting the deformation textures of both alpha and beta phases at extrusion temperature. The model also takes into account the transformation of metastable beta phase to alpha phase in the cooling process, considering variant selection. The transformation texture components mostly have [0001] along extrusion direction, forming the primary component of alpha extruded texture. The model works well in predicting hot deformation texture of titanium alloy.
Study on Aerodynamic Characteristics of Super High Speed Elevator
Authors: Yang Zhe , Zhang Qing , Zhang Ruijun
Published: June 2019

With the increase of elevator running speed, the influence of aerodynamic force on elevator becomes more and more obvious, and the impact is also increasing gradually. In this paper, the Computational Fluid Dynamic numerical simulation method is used to simulate and analyse the aerodynamic characteristics of elevator car under the influence of different operating speed and distance from side of car to hoistway wall by establishing full-scale model of elevator and hoistway. The results show that when the car is in a symmetrical position, the aerodynamic characteristics on both sides always show obvious symmetry. With the decrease of distance from side of car to hoistway wall and the operating speed of the car, the flow field around the car changes intensified, and the aerodynamic forces on the side of the car will also increase significantly.
Study on Transverse Vibration Characteristics of High-Speed Elevator under Gas-Solid Coupling
Authors: Liu Jie , Zhang Ruijun , Zhang Qing
Published: June 2019

The purpose of this paper is to study the transverse vibration characteristics of highspeed elevator under the action of gas-solid coupling. A three-dimensional physical model of the high-speed elevator is established, the aerodynamic loads on the car under different transverse vibration states (translation and rotation) are numerically solved, and then the relationship between the different transverse vibration states of the car and the aerodynamic loads is obtained. The transverse vibration model of the high-speed elevator based on gas-solid coupling is established by transferring the attitude parameters and aerodynamic parameters of the car in real time combined with the guide excitation. Finally, the transverse vibration characteristics of high-speed elevators with or without gas-solid coupling are compared and analysed by solving the model with an example. The results show that the effect of gas-solid coupling on the transverse vibration acceleration peak value of high-speed elevator is greater when the running speed is greater than 4m/s, and the greater the speed, the more obvious the effect is, which provide some theoretical guidance for the analysis and control of the transverse vibration of high-speed elevator.
Development of a Robotic Structural Steel Cutting System
Authors: Zhao Xijun , Chung Yunchan
Published: June 2019

Curved buildings and structures are getting popular and digital fabrication of the structural steels has been successfully tried in several ways. This study presents a development of a robotic system cutting structural steels and marking texts on the steels using digital information of shapes. A configuration of the overall system is explained based on functional decomposition of conventional cutting systems. The cutting system consists of a robotic system and a handling system, and the main functions of the cutting system are classified as translation, orientation, alignment, and cutting. A digital model of the system was created and tested in a robot simulation system. A robot tool-path generation system was also developed. The tool-path generation system uses the DSTV file, an industry standard for the shape of a structural steel, to generate robot job files. This study also provides robot workspaces in which the cutting tool can safely access and cut the workpieces. The proposed system was tested for cutting structural steels clamped in front of the robot. The results show that the generated tool-paths are valid in cutting the structural steel and the possibility of an overall robotic system for cutting structural steels.
CFD Simulation of Cavitation Bubble Collapse near a Rectangular Groove Wall
Authors: Yu Yan , Sun Changguo , Liu Yazhe , Liu Yang , Xia Dongsheng
Published: June 2019

The collapse process of a vapour bubble near to a rectangular groove wall is numerically simulated based on the Volume of Fluid (VOF) method with considering bubble surface tension, liquid viscosity and gas compressibility. Under the conditions of different stand-off parameters, evolution of the bubble profile, the jet velocity and the shock pressure around the bubble are obtained. Variation of the maximum jet velocity and the shock pressure around the bubble with the stand-off parameters is analyzed. Moreover, the impact pressure on the groove wall induced by the jet and the shock wave is also discussed, respectively. Cavitation erosion of the groove wall is explored for different stand-off parameters.
Double Fuzzy Logical Control in Hybrid Power Supply Electric Vehicle
Authors: Wu Meng-Qiang , Guo Hao , Xu Zi-Qiang , Yang Yun-Long , Yuan Zhi-Mei , Xiao Chao-Qun , Liu Jian
Published: June 2019

The hybrid power supply of fuel cell and super capacitor combines the advantages of high energy density of fuel cell with high power density of super capacitor. Based on the fuzzy logical control strategy, two fuzzy logical controllers are set up to participate in power distribution, and the simulation verification is carried out under the standard working Condition experiment, which effectively reduces the driving energy consumption of pure electric vehicles. This scheme control strategy is simple and easy to engineer.
Method for Determining Accurate Initial Air Pressure Range of Air Suspension Airbag Based on Vehicle Ride Comfort Simulation Analysis
Authors: Zhou Quan , Yuan Puguang , Tudor Tim , Wang Xudong , Guo Zhangwei , Huang Yihui , Sun Jingfeng , Wang Boyun
Published: June 2019

With the rapid development of automobile technology and the improvement of people’s quality of life, people put forward higher requirements for vehicle ride comfort. Shock absorption has become an important direction for automobile research, manufacturing and optimization. The traditional air suspension airbag delimits the initial air pressure range based on the bearing capacity of the airbag material, so the range of the pressure is inaccurate. Considering optimizing ride comfort of the vehicle, this paper proposes a method to determine the accurate initial air pressure range. In order to determine the accurate initial air pressure range of the airbag, this paper needs to know the vehicle ride comfort under any air pressure. The airbag spring stiffness is calculated using the airbag model in MATLAB environment. A shock absorber with appropriate damping coefficient is selected by using the single mass system model and the airbag spring stiffness. Suspension stiffness is calculated by constructing a single wishbone beam independent suspension model and using the airbag spring stiffness. The damping coefficient and suspension stiffness are introduced into the Simulink five-degree-freedom vehicle model to obtain the acceleration signals of every part including the seat whose RMS value of the acceleration signal is used to judge the ride comfort of the vehicle. Under the specific simulation conditions in this paper, there is an accurate range (14∼16kPa) in the rough range (12∼20kPa) of the initial air pressure of the airbag to make the vehicle ride smoothly.
A Road-Holding Index Based on Ride Dynamics for High-Downforce Racing Cars
Authors: Marchesin Felipe , Barbosa Roberto Spinola , Gadola Marco , Chindamo Daniel
Published: June 2019

This work builds on some of the current industry techniques used in racing to evaluate vertical dynamics performance and propose a new methodology to evaluate vehicle performance. The proposed method creates a quantitative numerical index from the classic tyre vertical load variation frequency response function with some novelties that cover all peculiarities of high downforce race cars. In this method the aerodynamic forces are included as non-linear functions vs ride height and it is shown that they affect system stiffness and damping. As a result, the system response changes as a function of vehicle longitudinal speed. The importance of non-linear suspension rates in this kind of vehicle is also highlighted. The proposed index can also be customized for a certain vehicle speed range. A Formula 3 racecar model has been used as an application example.
Regulation of Laboratory-Developed Tests
Authors: Genzen Jonathan R
Published: June 2019

Objectives

To provide a clinical laboratory perspective on the Verifying Accurate Leading-edge IVCT Development Act (VALID) discussion draft. This potential legislative effort, if enacted, would overhaul the regulatory oversight of in vitro diagnostics (IVDs) in the United States and create a single system for regulation of conventional IVDs and laboratory-developed tests (LDTs).

Methods

A concise literature-based review of LDT regulation is presented followed by a discussion of key concerns pertinent to clinical laboratories that should be considered in future IVD regulatory reform efforts.

Results

Key issues identified include the importance of fostering innovation, preserving patient safety, protecting the practice of laboratory medicine, and minimizing undue regulatory burden. Clinical laboratories are not equivalent to manufacturing facilities and would therefore encounter challenges in implementing device-centric regulatory oversight models.

Conclusions

It is imperative that a clinical laboratory perspective on LDTs is understood and incorporated prior to advancement of future legislative proposals.
Does Provider Specialty Matter?
Authors: Stubblefield Jeannie M , Lasley Mary V , Virant Frank S , Dickerson Jane A
Published: June 2019

Objectives

Multiple practice guidelines discourage indiscriminate use of broad panels of allergen-specific IgE (sIgE) tests due to increased risk of false positives and misinterpretation of results. We provide an analytical framework to identify specialty-specific differences in ordering patterns and effectiveness, which can be used to improve test utilization.

Methods

Test results from a tertiary pediatric hospital were analyzed by ordering specialty to evaluate size of allergen workups. Positivity rates were analyzed to determine effectiveness in selecting tests with high positive pretest probabilities. Laboratory test menu components were also evaluated.

Results

Our findings demonstrate 29% of sIgE tests are ordered as part of broad workups (>20 sIgE tests/date of service) contrary to the recommended testing approach. Detailed descriptions of ordering patterns and positivity rates are provided.

Conclusions

This study provides a framework for using a cross-sectional analytical approach to assess test utilization patterns and evaluate components of laboratory testing menus.
Attractiveness is positively related to World Cup performance in male, but not female, biathletes
Authors: Fawcett Tim W , Ewans Jack , Lawrence Alice , Radford Andrew N
Published: June 2019

Whole-organism performance capacity is thought to play a key role in sexual selection, through its impacts on both intrasexual competition and intersexual mate choice. Based on data from elite sports, several studies have reported a positive association between facial attractiveness and athletic performance in humans, leading to claims that facial correlates of sporting prowess in men reveal heritable or nonheritable mate quality. However, for most of the sports studied (soccer, ice hockey, American football, and cycling), it is not possible to separate individual performance from team performance. Here, using photographs of athletes who compete annually in a multi-event World Cup, we examine the relationship between facial attractiveness and individual career-best performance metrics in the biathlon, a multidisciplinary sport that combines target shooting and cross-country skiing. Unlike all previous studies, which considered only male athletes, we report relationships for both sportsmen and sportswomen. As predicted by evolutionary arguments, we found that male biathletes were judged more attractive if (unknown to the raters) they had achieved a higher peak performance (World Cup points score) in their career, whereas there was no significant relationship for female biathletes. Our findings show that elite male athletes display visible, attractive cues that reliably reflect their athletic performance.
The Whole Story: The Dilemma of the Domestic Violence Protection Order Narrative
Authors: Fitzgerald Robin , Douglas Heather
Published: June 2019

The complaint narrative, in which victims describe their experiences of abuse as part of the domestic violence protection order application process, has been questioned on the basis that quality and outcome might vary depending on who completes the form. Using a mixed-methods narrative analysis approach, we advance this inquiry by examining whether distinct ‘types’ of narratives can be identified across a sample of protection order application narratives from the state of Queensland in Australia. We find three distinct narrative types that are differently associated with who makes the application and the protection order outcome. The results underscore the unevenness in the protection order process and equitable access to justice more broadly.
The antero-dorsal precuneal cortex supports specific aspects of bodily awareness
Authors: Herbet Guillaume , Lemaitre Anne-Laure , Moritz-Gasser Sylvie , Cochereau Jérôme , Duffau Hugues
Published: June 2019

The precuneus is a functionally heterogeneous area located on the medial face of the parietal cortex, wedged between the occipital cortex and the paracentral lobule. In view of its topological positioning, this associative cortex is well-placed to play an important role in multisensory integration, specific aspects of which participate to bodily awareness. However, this potential implication remains unestablished. We assessed bodily awareness longitudinally in 14 rare patients who underwent a surgery for a low-grade glioma mainly infiltrating the precuneus. To determine the brain locus the most frequently affected in patients showing bodily awareness disorders, we first contrasted the resection cavity distributions of patients with versus without bodily awareness disorders. We next applied ‘lesion network mapping’ to identify the networks functionally coupled with lesion locations causing bodily awareness disorder. Bodily awareness disorders were observed in half of patients after surgery, especially alien hand, macrosomatognosia and fading limb. Importantly, a dissociation was revealed between the antero-dorsal precuneus (bodily awareness disorders) and postero-dorsal precuneus (no bodily awareness disorders). Furthermore, bodily awareness disorder-related regions were specifically connected to a network of sensorimotor regions while others were connected with the default network. Altogether, the present findings indicate a critical role of the antero-dorsal precuneus in specific aspects of bodily awareness and in the maintenance of body schema.