bluuebunny/crossref_metadata_2025 huggingface dataset:
Water-cooling diamond anvil cells: An approach to temperature–pressure relation in heated experiments
Authors: Zhang Yanan , Wu Yue , Han Yonghao , Gao Yang
Published: October 2022

Temperature induced pressure drift in the diamond anvil cell (DAC) is a major issue in high-pressure high-temperature experiments. It is commonly acknowledged that these drifts originate from multiple factors, but no systematic descriptions have been made so far. By introducing an internal water-cooling system in the DAC, we have performed a systematic investigation into temperature induced pressure drifts to reveal the mechanism behind them and to find a proper experimental procedure to achieve minimal pressure variation in DAC’s heating experiment. It is revealed in this experiment that pressure variation during heating processes originates from multiple temperature related factors of the DAC. The variation itself can be considered as a rebalancing process of the compression forces on the sample chamber initiated by the disturbance caused by temperature elevation. It is possible to suppress pressure variation by maintaining the temperature of the DAC body at room temperature to ensure the consistency of compression on the sample chamber. At the same time, the best procedure for the heating experiments is to properly pre-heat the sample chamber equipped with the internal water-cooling system before performing the in situ measurements on the temperature-related properties at the pressurized and heated conditions. Our discovery provides a reliable procedure for the sample heating process in the DAC and helps resolve the complex mystery of the influence of the combination of pressure and temperature in high-pressure high-temperature experiments.
Görtler vortices behavior and prediction in dual-incident shock-wave/turbulent-boundary-layer interactions
Authors: Li Xin , Zhang Yue , Yu Hang , Lin Zheng-Kang , Tan Hui-Jun , Sun Shu
Published: October 2022

Görtler vortices (GVs) in dual-incident shock-wave/turbulent-boundary-layer interactions (dual-ISWTBLIs) are experimentally investigated in a Mach 2.48 flow. A double-wedge shock generator with two deflection angles of 8° and 5° is used to produce two incident shock waves (ISWs). Flow structures of the experiments with three different shock-wave distances were visualized by the ice-cluster-based planar laser scattering technique at two orthogonal planes (x–y and x–z planes). The images in the x–y plane present three types of flow patterns of dual-ISWTBLIs corresponding to the first type with a triangle-like separation, the second type with a quadrilateral-like separation, and the third type with two isolated interactions induced by the two ISWs. The images in the x–z plane indicate that the GVs exist in the first type of dual-ISWTBLI originating in the vicinity of the apex of the separation region and cover nearly the whole spanwise range of the reattachment region. By comparison, the GVs intermittently occur in the limited spanwise range of the reattachment region in the second type of dual-ISWTBLI. No GVs are observed in the third type of dual-ISWTBLI because no visible separation is induced under the experimental conditions considered in this situation. In addition, based on the wall-pressure distribution in the former two types of dual-ISWTBLIs, this paper proposes a method to estimate the mean-flow streamline curvature in the reattachment region, thereby obtaining the criteria for the existence of GVs, according to which reasonable explanations for the different distributions of GVs in the two types of dual-ISWTBLIs are provided.
Toward accurate ferroelectric polarization estimation in nanoscopic systems
Authors: Mohapatra Sambit , Weber Wolfgang , Bowen Martin , Boukari Samy , Da Costa Victor
Published: October 2022

The nanoscopic characterization of ferroelectric thin films is crucial from their device application point of view. Standard characterization techniques are based on detecting the nanoscopic charge compensation current (switching current) caused by the polarization reversal in the ferroelectric. Owing to various surface and bulk limited mechanisms, leakage currents commonly appear during such measurements, which are frequently subtracted using the device I–V characteristic by employing a positive-up-negative-down measurement scheme. By performing nanoscopic switching current measurements on a commonly used ferroelectric, BiFeO3, we show that such characterization methods may be prone to large errors in polarization estimation on ferro-resistive samples due to current background subtraction issues. Specifically, when the resistance of the ferroelectric thin film is associated with polarization reversal, background current subtraction is not accurate due to the mismatch of the I–V characteristics for two polarization states. We show instead that removing the background current by an asymmetric least-squares subtraction method, though not perfect, gives a much better estimation of the ferroelectric properties of the sample under study.
Approximate solution to a generalized Van der Pol equation arising in plasma oscillations
Authors: Alhejaili Weaam , Salas Alvaro H. , El-Tantawy S. A.
Published: October 2022

Motivated by some published theoretical investigations and based on the two-fluid model, nonlinear plasma oscillations are analyzed and discussed in the framework of the generalized Van der Pol equation. This equation is analyzed and solved using two different analytical approaches. In this first approach, the ansatz method is carried out for deriving an approximation in the form of a trigonometric function. In the second approach, the Krylov–Bogoliubov–Mitropolsky (KBM) technique is applied for obtaining a high-accurate approximation. The obtained approximations are compared with the numerical approximation using the Runge–Kutta (RK) method. Moreover, the distance error between the obtained approximations (using the ansatz method and the KBM technique) and the RK numerical approximation is estimated. In our investigation, both the proposed methods and obtained approximations can help many authors investigate several nonlinear oscillations in different plasma models and fluid mechanics.
Two-equation turbulent viscosity model for simulation of transitional flows: An efficient artificial neural network strategy
Authors: Wu Lei , Cui Bing , Xiao Zuoli
Published: October 2022

Laminar-to-turbulent transition phenomena are ubiquitous in natural and industrial flows. As to the Reynolds-averaged Navier–Stokes (RANS) simulation method, the workhorse for accurate prediction of such flow regime boils down to the consideration of the transition effect in turbulence modeling. In this paper, an industrial–practical transition–turbulence model with excellent accuracy, robustness, and efficiency is established by the fully connected artificial neural network (ANN), which maps the relation between the RANS mean flow variables and an intermittency factor. A one-equation local correlation-based transition model coupled with Menter's shear stress transport (SST) model is taken as the benchmark. The present two-way coupling ANN model is trained with two National Advisory Committee for Aeronautics (NACA) airfoils, that is, NACA0012 and NACA2418, at various angles of attack and Mach numbers, while tested with the A-airfoil, NACA0015, and RAE 2822 supercritical airfoils in different flow states. The a posteriori test results manifest that the mean pressure coefficient, skin friction coefficient, size of laminar separation bubble, mean streamwise velocity, Reynolds shear stress, and lift/drag/moment coefficient predicted by the ANN model are all in good agreement with those given by the benchmark transition-based SST model. Furthermore, the ANN model exhibits higher calculation efficiency and convergence speed than the traditional transition-predictive SST model. The present work may pave a new way for machine learning methods to be used in integrated transition–turbulence modeling toward industrial applications.
High-order mode bulk acoustic wave resonators based on polarity-inverted SiAlN/AlN multilayered films for high-frequency operation
Authors: Sekimoto Jun , Suzuki Masashi , Kakio Shoji
Published: October 2022

AlN film bulk acoustic wave (BAW) resonators operating at above 5 GHz for next generation mobile communications present some problems, such as the very thin thickness of the piezoelectric film and electrode films. These cause degradations of the power handling capability, electromechanical coupling factor, and Q value in film BAW resonators. Polarity-inverted multilayered AlN film BAW resonators can operate in high-order mode resonance. Therefore, an n-layer polarity-inverted film BAW resonator has n-times thicker piezoelectric film thickness than a standard BAW resonator with a monolayer piezoelectric film operating at same frequency. However, fabrication methods for polarity-inverted multilayered AlN films have not been established. This paper examines the effect of Si doping on AlN films on the crystal orientation, polarity direction, and electromechanical coupling factor (kt2). Furthermore, we fabricated and evaluated two- to eight-layer polarity-inverted SiAlN/AlN film high-overtone bulk acoustic wave resonators (HBARs). The polarity of the SixAl1−xN films inverted around x = 0.024–0.13. The crystal orientation and kt2 of the SixAl1-xN films were degraded with increasing Si concentration x. The eight-layer polarity-inverted SiAlN/AlN film HBAR resonated in the eighth mode. Moreover, the experimental longitudinal wave insertion loss exhibited a similar trend to the theoretical curve calculated by a Mason's equivalent circuit model considering the polarity inverted structure. The eight-layer polarity-inverted HBARs had approximately eight-times thicker piezoelectric film thickness than the monolayer AlN film HBAR. The insertion loss improved with increasing the number of polarity-inverted layers.
Characteristic boundary layer evolution in globulitic solidification of alloys with interface curvature and attachment kinetics
Authors: Li Bohan , Xing Hui , Jing Hanxu , Hu Rui
Published: October 2022

The characteristic boundary layer evolution in globulitic solidification of alloys was investigated by using the Landau transformation method that takes into account attachment kinetics and interface curvature. The accuracy of the numerical solution was verified by comparing numerical results with an analytical solution without curvature and kinetic effects. Numerical results show that the increase of the kinetic coefficient results in the decrease of the value of the equilibrium interface liquid concentration, and the normal velocity of the interface was negatively correlated with the kinetic coefficient. We found that the thickness of the quasi-steady characteristic boundary layer is close to that of the unsteady one during globulitic solidification when the supersaturation is small. With the supersaturation increasing, it deviates from the unsteady one. This indicates that the kinetic effect cannot be ignored in the numerical simulations of rapid solidification. It is of practical significance to study the rapid solidification process and predict the microstructure.
Transient electron energy-loss spectroscopy of optically stimulated gold nanoparticles using picosecond pulsed electron beam
Authors: Kuwahara Makoto , Mizuno Lira , Yokoi Rina , Morishita Hideo , Ishida Takafumi , Saitoh Koh , Tanaka Nobuo , Kuwahara Shota , Agemura Toshihide
Published: October 2022

Ultrafast phenomena in gold nanotriangles (AuNTs) were investigated using a transient electron energy-loss spectroscopy (TEELS) technique under irradiation from a 150-fs pulse laser with a wavelength of 780 nm. This investigation was conducted using a time-resolved transmission electron microscopy method that was developed to measure the dynamics of nanomaterials. Enhancement of the intensity and energy-width broadening of the energy loss were observed at the EEL peaks associated with surface and bulk plasmons on the AuNTs. The TEELS measurement revealed two decay processes of 7.8 ps and longer than 100 ps that compensate for relaxation times of excited surface plasmons using transient absorption spectroscopy. The results show that the bulk and surface plasmons have the same time evolution, i.e., that the excited electrons on the surface and in the bulk have the same relaxation processes in both electron–phonon and phonon–phonon interactions. The time evolution of electronic and lattice temperatures was also estimated based on the measured relaxation time using a two-temperature model, which revealed the volume expansion of the AuNTs and clarified the energy shifts of plasmons. Details of excited electrons in nanoparticles investigated via plasmon energy loss are expected to facilitate improvement in the performance for energy harvesting of photons in nanostructure-controlled materials.
Effects of trailing-edge serration shape on airfoil noise reduction with zero incidence angle
Authors: Hu Ya-Sen , Zhang Peng-Jun-Yi , Wan Zhen-Hua , Liu Nan-Sheng , Sun De-Jun , Lu Xi-Yun
Published: October 2022

When controlling the trailing-edge (TE) interference noise of airfoil, the design of the TE serration shape is still an open issue. To this end, the flow and noise generation for different TE serration shapes are explored by the wall-resolved implicit large-eddy simulation and acoustic analogy. The feather-like serrations are found to achieve the most prominent noise reduction among the four types of curved serrations, especially in the low-frequency range. With the aid of acoustic analogy, the coherence analysis of far-field noise produced by the dipole sources on the airfoil surface is performed. The results show that destructive interference is still the critical mechanism responsible for noise reduction. Considering only the dipole sources, we find that the feather-like serrated TE shape can obtain the best noise reduction performance among all the serrated cases. Furthermore, since flow structures are reorganized near the TE serrations, we investigated the flow noise sources quantitatively in the near field. In these cases, the noise source due to flow structures is suppressed to a greater extent in the feather-like serrated case near the TE serration roots. Consequently, the above findings indicate that the feather-like serration favors suppressing dipole and flow noise sources in the near field, which makes it an efficient configuration for reducing airfoil noise.
Experimental study on the effects of the cone nose-tip bluntness
Authors: Liu Meikuan , Han Guilai , Li Zongxian , Jiang Zonglin
Published: October 2022

In this Letter, hypersonic boundary-layer transition was investigated on a large-scale cone with a height of 3 m and a half-cone angle of 7° at a zero angle of attack in the JF-12 hypersonic flight duplicate shock tunnel. For the same freestream unit Reynolds number, with the increase in the bluntness Reynolds number, the transition Reynolds number has a trend of first increasing and then decreasing, showing a “transition reversal” phenomenon. As the bluntness increased, the high/low-frequency instability waves in the boundary-layer were modulated, which caused the boundary-layer transition to be delayed and then advanced.
Effect of expansion on the wall heat flux in a supersonic turbulent boundary layer
Authors: Tong Fulin , Dong Siwei , Duan Junyi , Yuan Xianxu , Li Xinliang
Published: October 2022

Direct numerical simulation of a spatially developing supersonic turbulent boundary layer at a Mach number of 2.25 and a friction Reynolds number of Reτ = 769 subjected to an expansion corner with a deflection angle of 12° is performed to investigate the effect of expansion on the characteristics of the wall heat flux (WHF). The effect of expansion on the statistical and structural properties of the fluctuating WHF is analyzed systematically in terms of probability density function, frequency spectra, and space-time correlations. Normalization using the local root mean square value yields good collapse of the probability density function curves. Unlike with wall pressure frequency spectra, it is found that expansion has little influence on the low-frequency components of the WHF spectrum. The correlation results show that the main effect of expansion is to increase the characteristic length scales and convection velocity of the WHF fluctuation in the post-expansion region. Furthermore, a direct comparison between the conditionally averaged flow fields and those presented in the authors' previous work [Tong et al., Phys. Fluids 34, 015127 (2022)] is performed to uncover the effect of expansion on the flow structures associated with extreme positive and negative WHF fluctuation events. We highlight that the extreme positive event emerges below a small hot spot under the action of a strong Q4 event, whereas the extreme negative event is relatively insensitive to expansion and still occurs between a pair of strong oblique vortices. In addition, we decompose the mean WHF into seven physics-informed contributions and quantify the effect of expansion on the dominating components with the aid of the bidimensional empirical mode decomposition method. The scale-decomposed results demonstrate quantitatively that expansion decreases the contribution of the large-scale structures in the outer region but the small-scale structures in the near-wall region contribute heavily to the mean WHF generation in the downstream region.
New properties of boron-oxygen dimer defect in boron-doped Czochralski silicon
Authors: Khirunenko L. I. , Sosnin M. G. , Duvanskii A. V. , Abrosimov N. V. , Riemann H.
Published: October 2022

Silicon doped with boron is the most widely used material in modern microelectronic devices based on p-Si. Therefore, it is important to thoroughly understand boron’s role in the processes of defect-impurity interaction in Si both on growing the material and during operation of devices. In this work, interactions of boron with oxygen in Si are investigated by studying boron absorption intracenter transitions, which are known to be highly sensitive to the local environment. In boron-doped Si, two lines with maxima at 228 and 261.3 cm−1 were detected. The linear dependence of lines intensity on boron concentration and the quadratic on oxygen content testifies that the defect responsible for the lines can be identified as BsO2i. The observed absorption lines correspond to the transitions from the ground to the excited states of boron, which are shifted toward lower frequencies relative to the main transitions due to a deformation perturbation from neighboring oxygen atoms. The activation energy of annealing and ionization energy of defect are determined. The properties of the registered ВsO2i defect differ from the known ВsO2 associated with the light-induced degradation of solar cells by local configuration. The data obtained testify that the ВsO2i defects with different properties can be formed in Si and must be taken into account when developing Si:B-based devices because they can play an important role in charge carrier transfer and affect the electrical and optical parameters of the material.
Computational investigation of natural ventilation induced by solar chimneys: Significance of building space on thermofluid behavior
Authors: Xu Fei , Xu Songzhe , Xiong Qingang
Published: October 2022

A solar chimney is a typical device to harness naturally available energy resources to power ventilation inside buildings. A comparative computational fluid dynamics study of the flow and thermal mechanics inside solar chimneys is performed in this study. We utilize a variational multiscale formulation to model the combined turbulent/laminar flow regimes presented in the natural ventilation problem in the sense of large eddy simulation. Nitsche type weak enforcement of Dirichlet boundary conditions is integrated into the numerical framework to address the excessive mesh resolution requirement in flow and thermal boundary layers. Numerical methodology is verified and validated against experimental data in a model room with a solar chimney, and good agreement between the present results and the reference data is obtained. Finally, the thermofluid characteristics are investigated in a building equipped with different solar chimney designs. Particular emphases are placed on the effects of attached building spaces to the flows within the chimneys. The results indicated that the complex and realistic building space in this paper reduces the turbulence entering the solar chimney inlet and, thus, increases the air flow rate by up to 48.9% compared with the frequently used standalone chimney simulation paradigm. In addition, the thermal comfort indices are presented. With increased air flow rate in the chimney, the overall thermal comfort in the building is likely to be decreased, suggesting the necessity in the future studies to consider thermal comfort as an optimization objective.
All-solid-state Li battery with atomically intimate electrode–electrolyte contact
Authors: Gu Zhenqi , Wang Kai , Zhu Feng , Ma Cheng
Published: October 2022

Creating epitaxial interfaces has recently been discovered as an effective strategy for addressing the electrode–electrolyte contact issue in all-solid-state Li batteries. The solid–solid composite electrode fabricated using this approach not only exhibits atomically intimate solid–solid contact but also possesses excellent tolerance to repeated cycling. Nevertheless, so far such epitaxial composite electrodes have only been cycled in cells with liquid-electrolyte-soaked separators, instead of all-solid-state cells, because realizing a thorough contact between the epitaxial composite electrode and the solid-electrolyte separator layer is difficult. Here, an all-solid-state cell with decent cycling performance was constructed using the epitaxial composite electrode. By infiltrating the Li4Ti5O12–Li0.33La0.56TiO3 ceramic pellet with a poly(ethylene oxide)-based solid electrolyte, a flat, non-porous surface that can effectively contact the separator layer is created. When integrated into an all-solid-state Li4Ti5O12–Li0.33La0.56TiO3 | Li6PS5Cl | Li13Si4 cell, this composite electrode was stably cycled for 100 cycles under 0.1 C at 80 °C with a final discharge capacity of 174.5 mAh g−1.
Influence of non-uniform thermal boundary on flow and heat transfer characteristics in rectangular channel
Authors: Wang Jiansheng , Ge Jianan , Fan Yuntian , Zhai Heli , Liu Xueling
Published: October 2022

In this paper, the flow behavior and heat transfer characteristic in a rectangular channel are numerically investigated. The non-uniform thermal boundary condition is arranged along the streamwise direction at the bottom of the rectangular channel. Furthermore, based on the flow field parameters obtained with numerical simulation, the dynamic modal decomposition (DMD) is carried out for viscous layer, buffer layer, and logarithmic region, respectively. The numerical results show that the hot bands of non-uniform thermal boundary affect the interaction of the velocity streaks along the streamwise direction, which reduces the vorticity of the buffer layer and the fluctuation of the velocity gradient vector. In the terms of entropy analysis, it can be found that the hot bands of non-uniform thermal boundary play a similar role of “riblets” and block the self-sustainment of the turbulent coherent structures. Moreover, the results of DMD manifest that the hot bands of non-uniform thermal boundary can improve the stability of viscous layer and buffer layer. The development of turbulent boundary layer is delayed by affecting the fluid characteristics in buffer layer. Compared to the channel without non-uniform thermal boundary condition, the maximum drag reduction rate of 8.35% can be achieved in considered cases, while a reduction in heat transfer performance of 2.74% occurs. In addition, the comprehensive performance coefficient increases slightly to 1.0013.
Spatial evolution of multi-scale droplet clusters in an evaporating spray
Authors: Pandurangan Nandhakumar , Sahu Srikrishna
Published: October 2022

Evaporative sprays are encountered in a wide range of engineering applications. Since clustering of droplets in sprays leads to strong inhomogeneity in the spatial distribution of droplet concentration that impacts mass, momentum, and energy exchange between the spray and the surrounding flow, a detailed investigation of droplet clustering in evaporating sprays is important. In the current research work, we experimentally investigate the spatial evolution of droplet cluster characteristics in an evaporating acetone spray injected from an air-assist atomizer. The droplet size and velocity are measured using Interferometric Laser Imaging for Droplet Sizing technique. In detail, characterization of the droplet clusters is achieved by the application of Voronoi analysis to particle image velocimetry images of the spray droplets. This approach not only identifies the droplet clusters but also provides area, length scale, and local droplet number density within the clusters. The identified droplet clusters are multi-scale and could be classified into either large- or small-scale clusters, which scale with spray half-width and Kolmogorov length scale, respectively. Experiments are also conducted in water spray under the same operating conditions. Despite the similarity in the droplet clustering process between the two sprays at small scales of air turbulence, some distinct trends are observed for the large-scale clusters in the acetone spray. This is attributed to the higher evaporation rate of acetone droplets, which promotes preferential accumulation of droplets.
Three-dimensional numerical study of the combined stroke swimmer
Authors: Ooms Gijsbert , Pourquie Mathieu , See-Wai Tam Daniel
Published: October 2022

A three-dimensional (3D) numerical simulation was performed using a combined stroke swimmer (deformable sphere) in an incompressible fluid of an infinite domain. The time-dependent deformation of the swimmer surface was assumed independent of the circumferential cross section in the flow direction of the swimmer. The 3D numerical simulation is an extension of our previous study that considered an axisymmetric numerical simulation. In particular, different fluid viscosities were considered for the same stroke of the swimmer. The effect of the swimmer inertia was studied by gradually decreasing the fluid viscosity. When the fluid viscosity decreased, the mean velocity of the swimmer changed its direction between Re = 0.00189 and Re = 0.0103. There is a transition between Re = 0.0103 and Re = 9.90 from the axisymmetric to three-dimensional flow that exhibits planar symmetry.
Three-dimensionality in the flow of an elastically mounted circular cylinder with two-degree-of-freedom vortex-induced-vibrations
Authors: Verma Mayank , De Ashoke
Published: October 2022

The study numerically investigates the three-dimensionality in the flow and two-degree-of-freedom (2DOF) vortex-induced-vibrations (VIV) characteristics of an elastically mounted circular cylinder. The cylinder is allowed to vibrate in both streamwise and transverse directions. A low value of mass-ratio (m*=2.546) with the zero-damping coefficient (ζ=0) is taken for the simulations. The primary aim is to understand the vortex shedding behind the cylinder and the transition characteristics of the wake-flow from two-dimensional (2D) to three-dimensional (3D). The Reynolds number (Re) is varied from 150 (fully 2D flow) to 1000 (fully 3D flow), which lies inside the laminar range. The reduced velocity (Ur) is varied 2≤Ur≤17, which covers all three major VIV branches [initial branch (IB), upper branch (UB), and the lower branch (LB)]. The oscillating cylinder sweeps the figure-eight trajectory. Two branches (IB, LB) and three branches (IB, UB, LB) amplitude responses are obtained for the low and high Re values, respectively. The wake behind the cylinder with 2DOF VIV undergoes the mode-C transition of 2D to 3D flow as opposed to the direct mode-B transition observed for transverse only VIV in the literature. The critical Re range of the 2D to 3D transition for the 2DOF VIV cylinder at a reduced velocity of 6 is around 250, less than the 1DOF VIV. Also, this range varies with the variation in m* and the streamwise to transverse oscillation frequency ratio (f*). A λz−Re map (where λz represents the spanwise wavelength of the streamwise vortices) is proposed for the 2DOF VIV, highlighting different modes of transition obtained for combinations of f* and Re.
Deconstructing the crustacean squat lobster genus
Authors: Machordom Annie , Ahyong Shane T. , Andreakis Nikos , Baba Keiji , Buckley David , García-Jiménez Ricardo , McCallum Anna W. , Rodríguez-Flores Paula C. , Macpherson Enrique
Published: October 2022

Unravelling the evolutionary history of taxa requires solid delimitation of the traits characterising these. This can be challenging especially in groups with a highly complex taxonomy. The squat lobster family Munididae contains more than 450 species distributed among 21 genera, Munida being the most speciose (~300 species). Previous phylogenetic studies, based on a small part of the diversity of the group, have suggested polyphyletic origins for Munida and the paraphyly of Munididae. Here, we use an integrative approach based on multi-locus phylogenies (two mitochondrial and three nuclear markers) paired with 120 morphological characters, to resolve taxonomic and evolutionary relationships within Munididae. Our study covers ~60% of the family’s known diversity (over 800 specimens of 291 species belonging to 19 of the 21 genera collected from the Atlantic, Indian and Pacific oceans). Using this information, we confirm the validity of most genera, proposing new ones in cases where the genetic analyses are compatible with morphological characters. Four well-defined munidid clades were recovered, suggesting that new genera should be erected in the currently recognised Munididae (three for the genus Agononida and eleven in Munida), and the genus Grimothea is resurrected. A key to all genera of the family is presented. Molecular clock estimates and ancestral biogeographic area reconstructions complement the taxonomic profiles and suggest some explosive diversification within Munididae during the Cretaceous and the Palaeogene. Further anagenetic events and narrow sympatry accounting for changes in distribution indicate a more limited dispersal capacity than previously considered. Our study unravels how diversification may occur in deep waters and further highlights the importance of the integrative approach in accurately delineating species in understanding the history of a family and the factors driving the evolution. ZooBank LSID: urn:lsid:zoobank.org:pub:16A61C4A-8D96-4372-820F-8EBDF179B43C
Distress responses during handling in urban and exurban bandiny, the New Holland honeyeater (Phylidonyris novaehollandiae), in southwestern Western Australia
Authors: Pearmain-Fenton M. , Gilson L. N. , Saunders B. J. , Bateman P. W.
Published: October 2022

Context Birds appear to be better suited than mammals or reptiles to adapt to fast-changing landscapes because of their greater mobility; however, the behavioural effects of urbanisation on birds in Australia remain broadly unexplored. Aims This study aimed to investigate the effects of urbanisation on behavioural responses exhibited by a common and widespread meliphagid, the bandiny or New Holland honeyeater (Phylidonyris novaehollandiae) while undergoing standard bird banding processes. Methods Five non-invasive techniques (alarm calling, wriggling, biting, breathing rate, and tonic immobility) were explored for efficacy in identifying underlying differences in distress arising from mist-netting at urban and exurban localities in southwestern Western Australia. Key results Breathing rate was the most important variable for identifying differences in post-capture distress response. The breathing rate of urban bandiny following capture was lower than those of exurban areas. All other parameters proved suboptimal for detecting differential behavioural responses to handling between urban and exurban populations, despite having been successfully used in other international studies. Conclusions We suggest that urban honeyeaters exhibit lower mean breathing rates due to chronic overstimulation in response to urban lifestyles and are not able to further elevate this behaviour in response to stressful stimuli. The failure of other approaches explored highlights the need to apply ecosystem-appropriate methods for investigating urbanisation within an Australian context. Implications Our results suggest that behavioural approaches to quantifying avian stress developed internationally require additional consideration when applied to the ecosystems of Australia, whose birds are evolved to accommodate a different regime of seasonality that has shaped them behaviourally and morphologically.
Comparing the development of cortex-wide gene expression patterns between two species in a common reference frame
Authors: James Sebastian S. , Englund Mackenzie , Bottom Riley , Perez Roberto , Conner Kathleen E. , Huffman Kelly J. , Wilson Stuart P. , Krubitzer Leah A.
Published: October 2022

Advances in sequencing techniques have made comparative studies of gene expression a current focus for understanding evolutionary and developmental processes. However, insights into the spatial expression of genes have been limited by a lack of robust methodology. To overcome this obstacle, we developed methods and software tools for quantifying and comparing tissue-wide spatial patterns of gene expression within and between species. Here, we compare cortex-wide expression of
RZRβ
and
Id2
mRNA across early postnatal development in mice and voles. We show that patterns of
RZRβ
expression in neocortical layer 4 are highly conserved between species but develop rapidly in voles and much more gradually in mice, who show a marked expansion in the relative size of the putative primary visual area across the first postnatal week. Patterns of
Id2
expression, by contrast, emerge in a dynamic and layer-specific sequence that is consistent between the two species. We suggest that these differences in the development of neocortical patterning reflect the independent evolution of brains, bodies, and sensory systems in the 35 million years since their last common ancestor.
Novel sulfur isotope analyses constrain sulfurized porewater fluxes as a minor component of marine dissolved organic matter
Authors: Phillips Alexandra A. , White Margot E. , Seidel Michael , Wu Fenfang , Pavia Frank F. , Kemeny Preston C. , Ma Audrey C. , Aluwihare Lihini I. , Dittmar Thorsten , Sessions Alex L.
Published: October 2022

Marine dissolved organic matter (DOM) is a major reservoir that links global carbon, nitrogen, and phosphorus. DOM is also important for marine sulfur biogeochemistry as the largest water column reservoir of organic sulfur. Dissolved organic sulfur (DOS) can originate from phytoplankton-derived biomolecules in the surface ocean or from abiotically “sulfurized” organic matter diffusing from sulfidic sediments. These sources differ in
34
S/
32
S isotope ratios (δ
34
S values), with phytoplankton-produced DOS tracking marine sulfate (21‰) and sulfurized DOS mirroring sedimentary porewater sulfide (∼0 to –10‰). We measured the δ
34
S values of solid-phase extracted (SPE) DOM from marine water columns and porewater from sulfidic sediments. Marine DOM
SPE
δ
34
S values ranged from 14.9‰ to 19.9‰ and C:S ratios from 153 to 303, with lower δ
34
S values corresponding to higher C:S ratios. Marine DOM
SPE
samples showed consistent trends with depth: δ
34
S values decreased, C:S ratios increased, and δ
13
C values were constant. Porewater DOM
SPE
was
34
S-depleted (∼-0.6‰) and sulfur-rich (C:S ∼37) compared with water column samples. We interpret these trends as reflecting at most 20% (and on average ∼8%) contribution of abiotic sulfurized sources to marine DOS
SPE
and conclude that sulfurized porewater is not a main component of oceanic DOS and DOM. We hypothesize that heterogeneity in δ
34
S values and C:S ratios reflects the combination of sulfurized porewater inputs and preferential microbial scavenging of sulfur relative to carbon without isotope fractionation. Our findings strengthen links between oceanic sulfur and carbon cycling, supporting a realization that organic sulfur, not just sulfate, is important to marine biogeochemistry.
Linguistic variation in customer reviews
Authors: Veselovsky Anna , Witzlack-Makarevich Alena
Published: October 2022

Informed by the framework of register analysis (Biber & Egbert 2018) and narrative analysis (Labov & Waletzky 1967), this paper studies customer reviews of assistive reading devices to identify intra-register variation between narratives of one’s own and another’s experience. The lexico-grammatical features differentiating the two experience types include the use of pronouns, references to animate and inanimate entities, patterns of user and product description, stance markers, negation, as well as expectation- and transaction-related lemmas. The study reveals that the distribution of these features is determined by the narrative ownership and the associated distinctions in expectations. Furthermore, the difference in narrative ownership results in variation with respect to the experience narrative composition.
Kv1 channel inactivation: Slow and slower
Authors: Short Ben
Published: October 2022

JGP study suggests that Kv1 channels share a common mechanism of slow inactivation, but that some family members are less prone to inactivate than others.
Nonlinear fast kurtogram for the extraction of gear fault features with shock interference
Authors: Ma Hao , Wang Jinrui , Han Baokun , Bao Huaiqian , Liu Zongling , Jiang Xingwang , Xing Shuo
Published: October 2022

The extraction of gearbox fault features under shock interference is an exceedingly difficult and valuable subject. The effective usage of the resonance frequency band is one of the solutions for this subject. However, the existing fast kurtogram (FK) method is prone to misdiagnosis due to the sensitivity of this method to aperiodic shocks. To overcome the sensitivity of the FK method to irrelevant shock, this paper proposes a nonlinear fast kurtogram (NFK) method. First, Z-score normalization is performed on the signal. Then, Sigmoid is used to improve the fault representation under shock interference. Third, the signal is divided into different frequency bands, and the band with the largest kurtosis is selected for filtering. Finally, the gear fault is analyzed by the square envelope spectrum. Simulation and experimental verification are used to demonstrate the effectiveness of the proposed method. The results show that gear fault features can be extracted under shock interference by the NFK method.
An intelligent fault diagnosis scheme for hydropower units based on the pattern recognition of axis orbits
Authors: Liu Wushuang , Zheng Yang , Ma Zening , Tian Bo , Chen Qijuan
Published: October 2022

Fault diagnosis plays an important role in maintaining the safe and stable operation of hydropower units. This paper presents an intelligent fault diagnosis scheme for hydropower units based on the pattern recognition of axis orbits. Firstl the vibration signals in the X and Y directions that constitute the axis orbit of the unit shaft are processed by the denoising method based on modal decomposition and permutation entropy. Second, the relative position and distribution of the axis orbits for different samples in the image window are unified. Third, the trained convolution neural network is chosen as the classifier to recognize the axis orbit image for fault-type recognition. Through the analysis of the measured data of a hydropower station, the influence of the sample number of the training set and the size of the axis orbit image on the performance of the proposed method and the necessity of denoising operation are studied. Compared with the existing methods, the proposed method has higher fault recognition accuracy and better generalization performance for different training sample sets. The results indicate that the proposed method is an effective alternative for the fault diagnosis of hydropower units.
Analysis of an exactly mass conserving space-time hybridized discontinuous Galerkin method for the time-dependent Navier–Stokes equations
Authors: Kirk Keegan , Horváth Tamás , Rhebergen Sander
Published: October 2022

We introduce and analyze a space-time hybridized discontinuous Galerkin method for the evolutionary Navier–Stokes equations. Key features of the numerical scheme include pointwise mass conservation, energy stability, and pressure robustness. We prove that there exists a solution to the resulting nonlinear algebraic system in two and three spatial dimensions, and that this solution is unique in two spatial dimensions under a small data assumption. A priori error estimates are derived for the velocity in a mesh-dependent energy norm.
Möbius randomness law for 𝐺𝐿(𝑚) automorphic 𝐿-functions twisted by additive characters
Authors: Jiang Yujiao , Lü Guangshi , Wang Zihao
Published: October 2022

In this article we unconditionally show that

{
μ
(
n
)
}

\{\mu (n)\}

is asymptotically orthogonal to

{

λ

π

(
n
)
e
(
n
α
)
}

\{\lambda _{\pi }(n)e(n\alpha )\}

where

λ

π

(
n
)

\lambda _{\pi }(n)

is the

n
n

-th Dirichlet coefficient of a

GL
⁡
(
m
)

\operatorname {GL}(m)

cusp form

π
\pi

. Our result does not assume any unproven hypothesis.
The Montesinos trick for proper rational tangle replacement
Authors: McCoy Duncan , Zentner Raphael
Published: October 2022

Recently Iltgen, Lewark and Marino introduced the concept of a proper rational tangle replacement and the corresponding notion of the proper rational unknotting number. In this note we derive a version of the Montesinos trick for proper rational tangle replacement and use it to study knots with proper rational unknotting number one. We prove that knots with proper rational unknotting number one are prime and classify the alternating knots with proper rational unknotting number one. We also study Montesinos knots with proper rational unknotting number one.
Rational numbers in ×𝑏-invariant sets
Authors: Li Bing , Li Ruofan , Wu Yufeng
Published: October 2022

Letb≥2b \geq 2be an integer andSSbe a finite non-empty set of primes not containing divisors ofbb. For any non-dense setA⊆[0,1)A \subseteq [0,1)which is invariant under×b\times boperation, we prove the finiteness of rational numbers inAAwhose denominators can only be divided by primes inSS. A quantitative result on the largest prime divisors of the denominators of rational numbers inAAis also obtained.
On the stable equivalences between finite tensor categories
Authors: Xu Yuying , Liu Gongxiang
Published: October 2022

We aim to study Morita theory for tensor triangulated categories. For two finite tensor categories having no projective simple objects, we prove that their stable equivalence induced by an exact

k
-

\Bbbk \text {-}

linear monoidal functor can be lifted to a tensor equivalence under some certain conditions.
Maclaurin type inequalities for multiplicatively convex functions
Authors: Meftah Badreddine
Published: October 2022

In this paper we establish a new identity, and then based on this identity we derive the Maclaurin’s inequality for multiplicatively convex functions.
Manifolds without real projective or flat conformal structures
Authors: Ruffoni Lorenzo
Published: October 2022

In any dimension at least five we construct examples of closed smooth manifolds with the following properties: (1) they have neither real projective nor flat conformal structures; (2) their fundamental group is a non-elementary Gromov hyperbolic group. These examples are obtained via relative strict hyperbolization.
Stable decompositions and rigidity for products of countable equivalence relations
Authors: Spaas Pieter
Published: October 2022

We show that the “stabilization” of any countable ergodic probability measure preserving (p.m.p.) equivalence relation which is not Schmidt, i.e. admits no central sequences in its full group, always gives rise to a stable equivalence relation with a unique stable decomposition, providing the first non-strongly ergodic such examples. In the proof, we moreover establish a new local characterization of the Schmidt property. We also prove some new structural results for product equivalence relations and orbit equivalence relations of diagonal product actions.
Free outer functions in complete Pick spaces
Authors: Aleman Alexandru , Hartz Michael , McCarthy John , Richter Stefan
Published: October 2022

Jury and Martin establish an analogue of the classical inner-outer factorization of Hardy space functions. They show that every function

f
f

in a Hilbert function space with a normalized complete Pick reproducing kernel has a factorization of the type

f
=
φ
g

f=\varphi g

, where

g
g

is cyclic,

φ
\varphi

is a contractive multiplier, and

‖
f
‖
=
‖
g
‖

\|f\|=\|g\|

. In this paper we show that if the cyclic factor is assumed to be what we call free outer, then the factors are essentially unique, and we give a characterization of the factors that is intrinsic to the space. That lets us compute examples. We also provide several applications of this factorization.
Character sheaves for symmetric pairs: Special linear groups
Authors: Vilonen Kari , Xue Ting
Published: October 2022

We give an explicit description of character sheaves for the symmetric pairs associated to inner involutions of the special linear groups. We make use of the general strategy given in Vilonen and Xue [Character sheaves for classical symmetric pairs, Represent. Theory 26 (2022), 1097–1144] and central character consideration. We also determine the cuspidal character sheaves.
Leprosy Caused byMycobacterium lepromatosis
Authors: Romero-Navarrete Marina , Arenas Roberto , Han Xiang Y , Vega-Memije Maria Elisa , Castillo-Solana Aureliano D
Published: October 2022

Objectives

Leprosy is caused by Mycobacterium leprae or Mycobacterium lepromatosis. This study reviews literature on M lepromatosis and reports on a Mexican family with this infection.

Methods

The review included all primary studies. Family history and surveys were used to uncover the infection cluster. Genome-based differential polymerase chain reactions were designed to detect etiologic agents.

Results

Since the discovery of M lepromatosis in 2008, 154 cases of M lepromatosis infection from 11 countries in the Americas and Asia have been reported, with most cases coming from Mexico. These cases included diffuse lepromatous leprosy (DLL) and other leprosy forms. Genomes of M lepromatosis strains have lately been sequenced, revealing 3,271,694 nucleotides and approximately 15% mismatches with M leprae. The Mexican family with leprosy involved the grandfather, mother, and 2 grandsons. The index was the oldest grandson, who manifested DLL and likely contracted the infection from his maternal grandfather approximately 13 years earlier. Family surveys diagnosed DLL in the index patient’s mother and borderline leprosy in his brother; both were likely infected by the index patient. M lepromatosis was identified from archived biopsies from the index patient and his mother, while M leprae was excluded.

Conclusions

M lepromatosis is a significant cause of leprosy in Mexico and requires better surveillance and control.