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This paper reports an electromagnetic indirect-driving scanning mirror with an enlarged mirror plate (17 mm × 17 mm) supported by high-strength polymer hinges for wide-field coaxial LiDAR (Light Detection and Ranging) applications. An indirect-driving mechanism was developed to achieve large tilting angle through mechanical amplification, while maintaining a relatively high resonance frequency of the enlarged mirror plate. A prototype mirror was designed, fabricated, and tested. A Hall scan position sensor was integrated to monitor the pose of the mirror in real time. The testing results show a coupled resonance frequency of 54.9 Hz with an optical tilting angle of ± 60 ° , corresponding to a field of view (FoV) of 12 0 °. A wide-field coaxial LiDAR system was also built based on the indirect-driving scanning mirror, and 2D imaging was demonstrated. [Display omitted] • An indirect-driving mechanism was developed to achieve a large tilting angle and a relatively high resonance frequency. • High magnification of the tilting angle of the mirror plate was achieved through mechanical coupling. • A Hall scan position sensor was integrated to monitor the actual position of the mirror plate in real time. • A coaxial LiDAR imaging system based on the indirect-driving scanning mirror was demonstrated. [ABSTRACT FROM AUTHOR]

In the application of distributed fiber optic sensing technology to obtain soil deformation, the deformation coordination between the sensing fiber optic (FO) cable and the soil medium is crucial. In this study, a three-dimensional numerical model for pullout test of a sensing cable in sand was constructed utilizing the discrete element method. The results indicate that, with the continuous increase in pullout displacement, the interface forces between the FO cable and soil particles steadily rise. After complete interface failure, these forces rapidly decrease. Throughout the pullout process along the distribution of the FO cable, the magnitude of interface forces undergoes significant changes depending on the contact state of the interface. As the confining pressure increases 0 MPa to 0.4 MPa, the effective contact between the FO cable and soil particles increases by approximately 0.4 times. The micro-anchors installed on the FO cable can generate anchoring forces. The anchoring forces initiate only after interface failure at their respective locations, restricting the development of strain at subsequent positions. We suggest defining the critical strain value, which corresponds to the maximum interface forces during the pullout process, and provides a basis for determining the interface strength between the FO cable and the soil. [ABSTRACT FROM AUTHOR]

• A mode-localized mass sensor composed of two different cantilevers is presented. • The initial asymmetric system is balanced with the electrostatic force. • The design allows to overcome manufacturing imperfections. • The mechanical coupling is taken into account in the proposed model. • The designed device is fabricated and the proposed model is experimentally validated. This paper presents a sensor using the mode localization phenomenon to detect a mass perturbation. It is composed of two cantilevers with different lengths and connected by a coupling beam. The short cantilever is electrostatically actuated and by changing the applied DC voltage, we can reduce its stiffness and reach the veering point, which corresponds to a balanced system. This principle allows us to overcome the manufacturing defect which perturbs the initial system. An analytical model using the Euler-Bernoulli beam theory is developed for the design. The equation of the continuous system is discretized with the Galerkin method and simulations are performed. The designed device composed of polysilicon coupled microbeams is then fabricated with the Multi-User MEMS Processes and an experimental investigation is carried out. Three devices with different coupling are considered with a length ratio of 0.98. This ratio is suitable to reach the veering point by using a DC balancing voltage around the half of the pull-in voltage. The comparison between theoretical and experimental results shows a good agreement for each device. [ABSTRACT FROM AUTHOR]

Abstract The widely used Pseudo-Two-Dimensional (P2D) cell model for Li-ion batteries is generally based on a simplified lithium diffusion model of active particles with certain geometry. In this work, we propose a two-level framework, which extends the P2D cell model and incorporates a mechanically coupled phase-field Cahn–Hilliard diffusion model of active particles. The phase-field model allows more detailed diffusion study in particles of general geometry and includes the full coupling of the mechanics and phase separation. To improve the computational efficiency, we manage to reduce one degree of freedom at the cell level by treating the ion flux between the electrolyte and active particle as a dependent quantity. The two-level framework is validated against the original one and applied to study the impact of particle geometry, finite deformation elasticity and phase separation on the cell performance. Results show that the oblate particle has better cell performance than other spheroidal particles. It is attributed to the mechanical drifting at the higher curvature. Highlights • Two-level framework incorporate multiphysical particle level modeling to cell mode. • The existence of stresses can enhance the bulk diffusion improve the cell performance. • The ellipsoidal particles have better cell performance than spherical particles. • Diffusion dynamic has a larger impact on the cell performance than particle shapes. • Capacity can be improved as the stiffness of the particle increase. [ABSTRACT FROM AUTHOR]

Abstract The present work investigates the effect of different outermost connector types on the hydrodynamic responses of a modular multi-purpose floating structure (MMFS) system. The MMFS system is preliminarily designed for a mild sea zone, which is composed of a number of standardized floating modules. In this study, the MMFS system has been simplified as a seven-module connected system. Considering the structural deformation of the MMFS system mainly occurs in the connectors among adjacent modules, each module is viewed as a rigid body. Both the hydrodynamic interaction effect and mechanical coupling effect among modules have been taken into consideration in the time-domain analysis. Different outermost connector designs have been proposed and investigated for the MMFS system. The results indicate that the hydrodynamic responses of the MMFS system are sensitive to the effects of the connector types, the wave phase, and the wavelength. The hinge-type design of the outermost connector can significantly reduce the extreme responses of both the bending moment and the shear force of the connectors. The additional PTO damper design for the outermost hinge-type connector can effectively reduce the motion of the outermost module, and also produce considerable wave energy. Highlights • Different outermost connector types can strongly influence the hydrodynamic responses of the MMFS system. • A proper PTO system for the outermost hinge connector, can effectively produce considerable wave energy. • The length-ratio effect on the hydrodynamic responses of the MMFS system has been figured out. • Proper outermost connector design can significantly reduce the extreme responses of the MMFS system. [ABSTRACT FROM AUTHOR]

Abstract Short- and long-term processes at or close to the subduction plate interface (e.g.,mineral transformations, fluid release, seismicity and more generally deformation) might be more closely related than previously thought. Increasing evidence from the fossil rock record suggests that some episodes of their long geological evolution match or are close to timescales of the seismic cycle. This contribution uses rocks recovered (episodically) from subduction zones, together with insights from thermomechanical modelling, to provide a new dynamic vision of the nature, structure and properties of the plate interface and to bridge the gap between the mechanical behavior of active subduction zones (e.g.,coupling inferred from geophysical monitoring) and fossil ones (e.g.,coupling required to detach and recover subducted slab fragments). Based on critical observations and an exhaustive compilation of worldwide subducted oceanic units (for which the presence near the plate interface, rock types, pressure, temperature, T/P gradients, thickness and timing of detachment can be assessed), the present study demonstrates how long-term mechanical coupling exerts a key control on detachment from the slab and potential rock recovery. Critical assessment of rock T/P characteristics indicates that these fragments can indeed be used as natural probes and provide reliable information on subduction interface dynamics down to ~2.8 GPa. Rock clusters are identified at depths of 30, 55–60 and 80 km, with some differences between rock types. Data also reveal a first-order evolution with subduction cooling (in the first ~5 Myr), which is interpreted as reflecting a systematic trend from strong to weak mechanical coupling, after which subduction is lubricated and mostly inhibits rock recovery. This contribution places bounds on the plate interface constitution, regular thickness (<300 m; i.e. where/when there is no detachment), changing geometry and effective viscosity. The concept of 'coupled thickness' is used here to capture subduction interface dynamics, notably during episodes of strong mechanical coupling, and to link long- and short-term deformation. Mechanical coupling depends on mantle wedge rheology, viscosity contrasts and initial structures (e.g.,heterogeneous lithosphere, existence of décollement horizons, extent of hydration, asperities) but also on boundary conditions (convergence rates, kinematics), and therefore differs for warm and cold subduction settings. Although most present-day subduction zone segments (both along strike and downdip) are likely below the detachment threshold, we propose that the most favorable location for detachment corresponds to the spatial transition between coupled and decoupled areas. Effective strain localization involves dissolution-precipitation and dislocation creep but also possibly brittle fractures and earthquakes, even at intermediate depths. Highlights • Subduction plate interface constitution, thickness, geometry and viscosity • Rocks recovered are reliable probes of subduction processes and thermal regimes • Long-term mechanical coupling controls rock recovery from subduction zones • Subduction cooling induces a long-term trend in rock detachment from the slab • Rock recovery is a proxy for long- and short-term subduction dynamics and coupling [ABSTRACT FROM AUTHOR]

• A tripod joint-CV joint transmission between parallel axis shafts can be homokinetic. • If connected to a CV joint, a tripod joint performs better than previously expected. • On cars, tripod joints can still be a good alternative to CV joints. • The transmission ratio of a tripod joint-CVJ driveshaft can now be exactly assessed. The paper presents a procedure to assess the instantaneous transmission ratio, in a generic configuration, of a driveshaft equipped with a tripod joint and a constant velocity joint of the fixed type. This mechanical transmission is used, for example, in automobiles to connect each half shaft of the differential to a driving wheel. After highlighting that the usual approach to evaluating the instantaneous transmission ratio is conceptually flawed, the paper proposes an original procedure to correctly assess the transmission ratio. The paper also proves that the considered driveshaft is homokinetic whenever the axes of the two end shafts are parallel. Numerical examples show application of the proposed procedure to case studies. [ABSTRACT FROM AUTHOR]

The purpose of this study was to retrospectively investigate the outcomes of Brånemark System Mk III TiUnite/Groovy implants placed in patients at Kobe University Hospital. Various risk factors for implant failure, including mechanical coupling, were investigated by univariate and multivariate analysis. The predictive variables investigated included age, sex, smoking habit, general health, history of radiation therapy, application of a dentomaxillary prosthesis, type of prosthesis, use of alveolar bone augmentation, site of implant insertion, mechanical coupling between implants, and the length and diameter of the implants. Of the 907 implants investigated, only 23 were unsuccessful; the overall survival rate was 96.7%. Increased age, radiation therapy, application of a removable prosthesis or dentomaxillary prosthesis, lack of mechanical coupling between implants, and shorter implants (≤8.5 mm) were significant risk factors for implant failure according to univariate analysis ( P < 0.05). Multivariate analysis identified a significant association ( P < 0.05) between dental implant failure and a lack of mechanical coupling between implants (odds ratio 6.88) and shorter implants (≤8.5 mm) (odds ratio 3.43). The findings of this study demonstrated multivariate relationships between various risk factors and dental implant failure. [ABSTRACT FROM AUTHOR]

Subduction infancy corresponds to the first few million years following subduction initiation, when slabs start their descent into the mantle. It coincides with the transient (yet systematic) transfer of material from the top of the slab to the upper plate, as witnessed by metamorphic soles welded beneath obducted ophiolites. Combining structure–lithology–pressure–temperature–time data from metamorphic soles with flow laws derived from experimental rock mechanics, this study highlights two main successive rheological switches across the subduction interface (mantle wedge vs. basalts, then mantle wedge vs. sediments; at ∼800 °C and ∼600 °C, respectively), during which interplate mechanical coupling is maximized by the existence of transiently similar rheologies across the plate contact. We propose that these rheological switches hinder slab penetration and are responsible for slicing the top of the slab and welding crustal pieces (high- then low-temperature metamorphic soles) to the base of the mantle wedge during subduction infancy. This mechanism has implications for the rheological properties of the crust and mantle (and for transient episodes of accretion/exhumation of HP-LT rocks in mature subduction systems) and highlights the role of fluids in enabling subduction to overcome the early resistance to slab penetration. [ABSTRACT FROM AUTHOR]

Distributed fiber optic sensing (DFOS) has recently emerged as a novel sensing technology for obtaining spatially continuous deformation of loose sediment. During the measurement, the mechanical coupling between the sediment and embedded fiber-optic cable determines the accuracy of the results. However, it remains a major challenge to properly assess such coupling behavior in both laboratory and in-situ tests. To investigate the pullout characteristics of a fiber-optic cable embedded in loose sediment, we established a two-dimensional model consisting of 205,909 active elements using high-performance discrete element numerical simulation software (MatDEM). We found that the simulations using the discrete element method well reproduced the pullout behaviors of fiber-optic cable embedded in soil, and this was verified by the experiment. In particular, the simulations obtained the interfacial shear stress distributions along the cable-sediment interface and the energy conversion processes, which were both determined by the confining pressures. The results revealed that the slip depth (L s) can better indicate the cable-soil coupling capability than the strain propagation length (L ε). Accordingly, we suggested two evaluation methods for the mechanical coupling of cable and sediment, one employing L s obtained by the simulations and the other employing the effective critical strain (ε cr) obtained from the actual measurements. The discrete element method filled the gaps in understanding the mechanical coupling of the sediment and the embedded fiber-optic cable and it can be a useful tool for evaluating the cable-sediment coupling behaviors. • We study the pullout behavior of fiber-optic cable embedded in loose sediment. • We establish a discrete element model using MatDEM. • The confining pressure determines the interfacial behavior of cable and sediment. • We propose two methods to evaluate the mechanical coupling of cable and sediment. [ABSTRACT FROM AUTHOR]

Ion channels are the “building blocks” of the excitation process in excitable tissues. Despite advances in determining their molecular structure, understanding the relationship between channel protein structure and electrical excitation remains a challenge. The Kv7.1 potassium channel is an important determinant of the cardiac action potential and its adaptation to rate changes. It is subject to beta adrenergic regulation, and many mutations in the channel protein are associated with the arrhythmic long QT syndrome. In this theoretical study, we use a novel computational approach to simulate the conformational changes that Kv7.1 undergoes during activation gating and compute the resulting electrophysiologic function in terms of single-channel and macroscopic currents. We generated all possible conformations of the S4–S5 linker that couples the S3–S4 complex (voltage sensor domain, VSD) to the pore, and all associated conformations of VSD and the pore (S6). Analysis of these conformations revealed that VSD-to-pore mechanical coupling during activation gating involves outward translation of the voltage sensor, accompanied by a translation away from the pore and clockwise twist. These motions cause pore opening by moving the S4–S5 linker upward and away from the pore, providing space for the S6 tails to move away from each other. Single channel records, computed from the simulated motion trajectories during gating, have stochastic properties similar to experimentally recorded traces. Macroscopic current through an ensemble of channels displays two key properties of Kv7.1: an initial delay of activation and fast inactivation. The simulations suggest a molecular mechanism for fast inactivation; a large twist of the VSD following its outward translation results in movement of the base of the S4–S5 linker toward the pore, eliminating open pore conformations to cause inactivation. [ABSTRACT FROM AUTHOR]

The formation of recovery stresses in a restrained Fe–Mn–Si–Cr–Ni–VC shape memory alloy used for mechanical coupling and prestressing has been investigated with special emphasis on non-ideal restraints that might reduce the recovery stress. The evolution of recovery stresses in the presence of different initial gaps and elastic restraints was investigated experimentally. The results show that the alloy can still produce substantial recovery stresses even under non-ideal restraining conditions. In a second part, the experimental results are analyzed using techniques from constitutive modelling to investigate the evolution of the recovery stress in a more rigorous way. For this purpose the measured strain is decomposed into its elastic, thermal expansion, and transformation parts. With these strain components, the development of the recovery stress during heating and cooling can be described for all different constraint conditions in a unified way. The analysis also shows why optimizing a material for high recovery stress is different from optimizing it for a large recovery strain. [ABSTRACT FROM AUTHOR]

This paper discusses a new installation method for floating offshore wind with installation procedure, essential variables, and fender system effects on the dynamic responses. The conventional installation method involves mating wind turbines and substructures in calm and protected waters and towing the assembled units to an operating site. Due to geographical, time, and economic disadvantages, this method may be challenging to meet the rapidly surging demand for floating wind power worldwide. The new onsite installation method was introduced as an alternative, using a catamaran to install fully assembled wind turbines at the operation site. The proposed concept can be employed to install and maintain fixed and floating offshore wind turbines in any location. While the conventional installation method consists of a series of installation processes, the proposed installation steps can be performed in parallel, suggesting more flexible operation planning. Fenders and wires were applied as a mechanical coupling system to enable onsite installation in harsh offshore environments. The fender system with pretensions on wires showed reduction effects on the relative horizontal displacement, relative vertical displacement, and relative alignment by approximately 78%, 64%, and 32%, respectively. Therefore, the fender system application can significantly increase the practicality of the onsite installation method. [Display omitted] • Novel onsite installation concept for floating offshore wind turbines is presented. • Benefits in the scheduling of the new installation procedure are discussed. • Expected challenges during the installation operation are investigated. • Critical responses of the installation concept are identified. • Feasibility and effects of applying the fender system are evaluated. [ABSTRACT FROM AUTHOR]

This paper reports a novel three degree-of-freedom (DoF) mechanical-coupled resonator whose mechanical system is a combination of a normal dual mass resonator (DMR) and an amplified dual mass resonator (ADMR). The mode localization phenomenon is firstly observed between the DMR mode (the anti-phase mode of DMR) and the ADMR mode (the anti-phase mode of ADMR). The resonant frequencies of the DMR and ADMR modes can be tuned to an identical value thanks to the unique structure design so that the amplitude ratio can be highly sensitive to the structural perturbation. The ADMR mode can approach the DMR mode and the amplitude ratio sensitivity can be enhanced by adjusting the inner stiffness, which largely affects the ADMR mode frequency while slightly influences the DMR mode frequency. Using the proposed triple-mass resonator scheme, it is not necessary to use an extremely weak coupling spring, which is advantageous for practical uses. The measurement results showed the as-fabricated frequency difference and sensitivity was 110 Hz and 210, respectively. The frequency difference could be effectively minimized to less than 0.2 Hz, and the sensitivity could be significantly enhanced to be 59922 by electrostatically softening the inner stiffness. [Display omitted] • Mode localization between DMR (dual mass resonator) and ADMR (amplified dual mass modes of triple-mass resonator. • Tunable sensitivity up to 56,700. [ABSTRACT FROM AUTHOR]

Abstract: Obduction is an odd geodynamic process characterized by the emplacement of dense oceanic “ophiolites” atop light continental plates in convergent settings. We herein present analog models specifically designed to explore the conditions (i.e., sharp increase of plate velocities — herein coined as ‘acceleration’, slab interaction with the 660 km discontinuity, ridge subduction) under which obduction may develop as a result of subduction initiation. The experimental setup comprises an upper mantle modeled as a low-viscosity transparent Newtonian glucose syrup filling a rigid Plexiglas tank and high-viscosity silicone plates. Convergence is simulated by pushing a piston with plate tectonics like velocities (1–10 cm/yr) onto a model comprising a continental margin, a weakness zone with variable resistance and dip (W), an oceanic plate (with or without a spreading ridge), a preexisting subduction zone (S) dipping away from the piston and an upper active continental margin, below which the oceanic plate is being subducted at the start of the model (as for the Neotethyan natural example). Several configurations were tested over thirty-five parametric models, with special emphasis on comparing different types of weakness zone and the degree of mechanical coupling across them. Measurements of displacements and internal deformation allow for a precise and reproducible tracking of deformation. Models consistently demonstrate that once conditions to initiate subduction are reached, obduction may develop further depending on the effective strength of W. Results (1) constrain the range of physical conditions required for obduction to develop/nucleate and (2) underline the key role of such perturbations for triggering obduction, particularly plate ‘acceleration’. They provide an explanation to the short-lived Peri-Arabic obduction, which took place along thousands of km almost synchronously (within ∼50–10 Myr), from Turkey to Oman, while the subduction zone beneath Eurasia became temporarily jammed. They also demonstrate that the emplacement of dense, oceanic material on continental lithosphere is not a mysterious process requiring extraordinary boundary conditions but results from large-scale, normal (oceanic then continental) subduction processes. [Copyright &y& Elsevier]

Abstract: Unlike the thermal structures of present-day subduction or collision zones, the variety of possible thermal evolutions (or “thermal regimes”) accompanying the transient stage of continental subduction (i.e., the shift from oceanic subduction to continental collision) remains poorly known. We herein show that the thermal regime of continental subduction can be confidently retrieved from three well-documented fossil settings (i.e., from high-pressure low temperature continental material from Oman, New Caledonia, Corsica) that were not modified by later collision or a later metamorphic imprint. Based on recently published data, we show the striking similarity of the overall thermal and tectonic patterns of these three HP belts derived from the subduction of a continental margin. These natural examples suggest that the thermal regime of continental subduction is largely invariant through time (hence suggesting a steady-state thermal structure) and independent from the initial geodynamic setting (i.e., from the initial thermal structure of oceanic subduction, the nature of the incoming plate or of the upper plate). We propose that continental cover units subducted over a short time period (i.e., ~10My) represent cold underplated material that buffers the subduction thermal regime, whatever the exact structure, nature, or thermal structure of incoming material. Similarities in the type, size and P–T conditions of the various tectonic units and in the overall tectonic organization point to specific accretionary-type subduction dynamics, yet to differences in long-term mechanical coupling between the three case studies. Our study thereby provides constraints on exhumation dynamics and models of continental subduction. [Copyright &y& Elsevier]

Abstract: Friction controls most of the strength of tectonic plate boundaries, and thus the force mutually exchanged between plates. Estimates of the plate-boundary friction-coefficient are therefore of paramount importance to our understanding of the lithosphere torque balance. However, several lines of evidence indicate that the friction-coefficient of plate margins is significantly lower than is measured in laboratory experiments on fractured rocks. This poses a significant limit to extrapolation from the laboratory scale to the large-scale of Earth''s lithosphere. The record of past and present-day plate motions represents an efficient probe into the torque balance of plate tectonics, because plate-motions readjust virtually instantaneously to temporal changes in driving and resisting forces. Here I derive inferences on the strength of large-scale plate boundaries by focusing on the convergence of the fast-moving Philippine Sea plate towards Eurasia, since subduction initiation ∼5Myr ago. Because at the present-day the Philippine slab reaches depths shallower than the 410-km transition zone in the upper mantle, its weight is unlikely to provide sufficient driving force to shear the trailing plate over the viscous mantle at the observed rates. Using global models of the coupled mantle/lithosphere system, I argue that frictional coupling with the Pacific and Eurasia plates is the main driver for the dynamics of the Philippine Sea plate. This allows me to infer that the friction-coefficient of large-scale plate boundaries is in range 0.01–0.07, and that the amount of sediments entering plate margins efficiently modulates the friction-coefficient, contributing significantly to its lateral variations. Importantly, I corroborate my conclusions by looking at the present-day vertical deformation of the Philippine Sea/Eurasia margin, evident from observed trench-parallel gravity anomalies. [Copyright &y& Elsevier]

Abstract: The Western Iratsu body of the Sanbagawa belt (SW Japan) represents a <2km thick garnet–epidote amphibolite slice with minor intercalated occurrences of eclogite. Equilibrium phase assemblage diagrams (pseudosections) for eclogite and garnet–epidote amphibolite from this body can be successfully used to reconstruct the pressure (P)–temperature (T) path and the evolution of the associated mineral assemblages. Microstructural observations combined with calculated pseudosections reveal two distinct stages of subduction-related metamorphism referred to as M1 and M2. P–T conditions of M1 evolved from 0.9GPa, 570°C to 1.2GPa, 660°C, implying relatively high thermal gradients possibly developed shortly after the initiation of subduction. The available age data and the characteristics of the P–T path suggest that the Western Iratsu body was detached from the slab at 1.2GPa (~40km depth) and the subsequent subduction occurred at a very slow rate due to weak mechanical coupling to the downgoing slab. The prograde metamorphism associated with the second subduction phase (M2) reached the eclogite facies (~1.8GPa, 510–560°C), but mafic rock compositions recrystallized into either eclogite or garnet–epidote amphibolite assemblages, depending on the bulk rock (CaO+Na2O)/(FeO+MgO) ratio. The thermal peak of M2 (~620°C at 1.6GPa) was attained during the early phase of exhumation. Further decompression and re-equilibration (M3) took place in the epidote-amphibolite facies. The M2 to M3 P–T evolution is associated with a progressive increase in thermal gradient (T/P ratio), which can be explained by thermal modeling as the result of the inflow of a very young hot section of the slab. The bulk density of the whole Western Iratsu body at the point of onset of exhumation—the return point—is estimated to be ~3180kgm−3, which is less than the density of mantle, implying that buoyant rise is a viable mechanism for its initial exhumation. Buoyant rise is in accordance with the widespread early-exhumation related deformation that has a dip-parallel stretching lineation. Exhumation of the buoyant discrete mafic slice along the decoupled slab–mantle interface could have been triggered by the heating that lead to fluid liberation and a resultant reduction of the rock strength. [Copyright &y& Elsevier]

Abstract: This study investigated whether people with low back pain (LBP) reduce variability of movement between the pelvis and thorax (trunk) in the transverse plane during gait at different speeds compared to healthy controls. Thirteen people with chronic LBP and twelve healthy controls walked on a treadmill at speeds from 0.5 to 1.72m/s, with increments of 0.11m/s. Step-to-step variability of the trunk, pelvis, and thorax rotations were calculated. Step-to-step deviations of pelvis and thorax rotations from the average pattern (residual rotations) were correlated to each other, and the linear regression coefficients between these deviations calculated. Spectral analysis was used to determine the frequencies of the residual rotations, to infer the relation of reduced trunk variability to trunk stiffness and/or damping. Variability of trunk motion (thorax relative to pelvis) was lower (P=0.02), covariance between the residual rotations of pelvis and thorax motions was higher (P=0.03), and the linear regression coefficients were closer to 1 (P=0.05) in the LBP group. Most power of segmental residual rotations was below stride frequency (∼1Hz). In this frequency range, trunk residual rotations had less power than pelvis or thorax residual rotations. These data show that people with LBP had lower variability of trunk rotations, as a result of the coupling of deviations of residual rotations in one segment to deviations of a similar shape (correlation) and amplitude (regression coefficient) in the other segment. These results support the argument that people with LBP adopt a protective movement strategy, possibly by increased trunk stiffness. [Copyright &y& Elsevier]

Abstract: In composite laminated plates the mechanical coupling is one of the significant properties which dominate the performance of a laminated plate structure in large out-of-plane deformations. Some effects of mechanical coupling on the post-buckling behavior of composite laminated plates have been studied in this paper by implementing a finite strip approach based on the concept of a rigorous post-buckling solution for composite plates and plate structures, namely the semi-energy approach, which has been originally developed by the authors of current paper. Moreover, to check the validity and soundness of presented semi-energy FSM the results obtained from developed approach are compared with those obtained from a fairly conventional and well exploited finite strip technique, namely the full-energy finite strip method as well as the obtained results from ANSYS (i.e. the general purpose finite element method software). In this paper, the post-buckling behavior of an anti-symmetric angle-ply square plate with the stacking sequence configuration as [±45]2 has been studied. Moreover, according to anti-symmetric nature of lamination in the mentioned plate there exists a mechanical coupling between in-plane membrane and out-of-plane twisting curvature; therefore, the results of this analysis have been referred as coupled solution in this paper. In order to evaluate the effects of mechanical coupling on the post-buckling performance of mentioned plates, the uncoupled solution has also been determined by precluding the coupling terms (i.e. B 16, B 26). The post-buckling load–end shortening and load-maximum out-of-plane deflection paths have been obtained for coupled as well as uncoupled solutions. The comparison between the obtained results by coupled and uncoupled solutions revealed markedly different behaviors due to presence of mechanical coupling in the anti-symmetric angle-ply laminates. The outcome of the paper can help structural designers have a better understanding of the effects of mechanical coupling on the post-buckling behavior of laminated composite plates at the design stage. [Copyright &y& Elsevier]

Megathrust earthquake rupture is highly influenced by seafloor bathymetric features such as oceanic fracture zones, seamounts, and ridges in convergent plate margins where these features subduct. Recent seismic reflection and refraction data reveal a trough-parallel subducted oceanic ridge that is attached to the descending Philippine Sea Plate beneath the accretionary wedge of the overriding Eurasian Plate in the eastern Nankai Trough subduction zone consisting of the Tonankai and Tokai segments. The seismic survey data confirm the existence of subducted paleo-Zenisu ridge that was suggested by just magnetic data, and as a result, expands its distribution to the west. The newly constrained subducted ridge that spans the two segments is estimated to be a maximum of ∼2.5 km high, ∼20–30 km wide, and ∼200 km long. Spatial mapping of the ridge shows that it is located roughly at the seaward edge of the coseismic rupture zone of the 1944 Tonankai earthquake (M=8.1). This ridge appears to be in close contact with the seaward end of the rigid backstop in the Tonankai segment. Both the spatial correlation and the ridge–backstop collision geometry suggest that the subducted ridge might be strongly mechanically coupled and may thus play a significant role as a seaward barrier inhibiting the 1944 earthquake rupture from propagating farther seaward. [Copyright &y& Elsevier]

A strong mechanical coupling scheme between two degrees of freedom (2-DOF) is proposed in this paper for resonance enhancement of silicon micromachined resonators. Two spring-mass-damping resonant units, with identical (or close) resonant frequency and great disparity in mass, are mechanically linked together to form a 2-DOF resonator. When the big unit (with bigger mass) is driven to resonate, a much-enlarged resonant amplitude of the small unit (with smaller mass) can be obtained, attributed to the strong mechanical coupling between the two units. PSPICE is used for simulation of the properties of the strong mechanical coupling effect. The simulation fairly verifies the mechanical coupling modeling of 2-DOF resonators and, furthermore, analyzes the effect of quality factor, which is dominated by damping, on the enlarged resonant amplitude, ratio of resonant amplitude between the two units, resonant frequency drift and resonant phase deviation. An ultra-thin silicon cantilever-shaped 2-DOF resonator consisting of a wide base-cantilever and a narrow working cantilever is fabricated with a high yield process. The 2-DOF resonator is driven in vacuum with incident laser light on the wide base cantilever. The resonant amplitude is detected with laser Doppler meter. Measurement results agree well with the strong mechanical coupling modeling of 2-DOF resonators. [Copyright &y& Elsevier]

Ultra-High Molecular Weight semi-crystalline polymers, such as Ultra-High Molecular Weight PolyEthylene (UHMWPE) exhibit strong wear and impact resistance, making them good candidates for structural applications in many industrial fields. At high strain rate and large strain, mechanisms of deformation are quite different from those involved in classical semi-crystalline polymers, mainly because chain disentanglements are almost impossible for very long macromolecules even at temperature far above the melting point. Thus, there is a need to develop specific models for these materials and, from the works of Deplancke and her co-workers (Deplancke et al., 2019; Deplancke et al., 2015) who developed a scalar description based on polymer physics, three-dimensional constitutive equations are developed in this work. The developed model proposes an innovative way to take into account the repartition of strain for a semi-crystalline polymer and more generally for a two-phase material. Moreover, by modelling the evolution of microstructure during the plastic deformation of the material, the model is able to reproduce quite fairly the mechanical behavior of UHMWPE for both loading and unloading. • Innovative three-dimensional mechanical modelling of semi-crystalline polymers. • Evolution of the mechanical coupling within the crystal network. • Large strain behavior of ultra-high molecular weight semi-crystalline polymers. [ABSTRACT FROM AUTHOR]

5 α -reductase inhibitors are regarded as a promising chemoprevention strategy to reduce the incidence and delay the progression of prostate cancer. Landmark clinical trials have shown the chemopreventive potential of these drugs, but they appear to be mostly effective in mild tumors and have also been correlated with a higher prevalence of advanced prostate cancer. Hence, the use of 5 α -reductase inhibitors for prostate cancer chemoprevention has become a controversial issue. The effects of these drugs on prostate cancer growth remain incompletely understood, but they are thought to promote apoptosis in the tumor. Additionally, 5 α -reductase inhibitors induce global prostate shrinkage, which decreases the tumor-inhibiting effect of the mechanical stress accumulated in prostatic tissue due to common prostate enlargement with age. Thus, the competition between this mechanical effect and apoptotic upregulation may explain the controversial outcomes of 5 α -reductase inhibitors on prostate cancer. Here, we extend our mechanically-coupled model of prostate cancer growth by including the mechanical and apoptotic action of 5 α -reductase inhibitors and explore their combined effect on an aggressive tumor in silico. Our simulations show that the apoptotic boost dominates in the first months of therapy but the long-term outcome of 5 α -reductase inhibitors depends on its competition with a decrease in hydrostatic stress caused by prostate shrinkage, which favors tumor growth. By combining moderate or strong prostate shrinkage with mild or intense apoptotic upregulation, our simulations show different tumor growth dynamics ranging from long-term inhibition of prostate cancer growth to rapidly growing large tumors, which may evolve towards advanced disease. Thus, our proposed mechanism for the action of 5 α -reductase inhibitors may contribute to resolve the controversy around the use of these drugs for chemoprevention and to gain insight on prostate cancer dynamics during its use. The computational technology used herein could also assist physicians to monitor prostatic tumors during 5 α -reductase inhibitor therapy and enable the early identification of responders from non-responders in a patient-specific manner. • We study mechanic and apoptotic effects of 5 α -reductase inhibitors on prostate cancer. • We derive an organ-scale, patient-specific computational model for this treatment. • Mechanical drug effects are parameterized with data from large clinical studies. • Our simulations show that apoptotic effects dominate in the short-term. • Drug-induced prostate shrinkage may overcome the apoptotic effect long-term. [ABSTRACT FROM AUTHOR]