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We present the results from a detailed analysis of our time-series spectroscopic observations and the Transiting Exoplanet Survey Satellite (TESS) photometric data of the eclipsing binary V389 Cas. The radial velocities (RVs) of the primary and faint secondary components were obtained from a total of 61 high-resolution spectra made between 2016 and 2019. The disentangling spectra were used to determine the effective temperature and projected rotational velocity of the primary star based on theχ²fitting statistic, yieldingT_eff,1 = 7720 ± 200 K and$v_{\mathrm{1}}\sin i_{\mathrm{rot}}=59\pm 7$km s⁻¹, respectively. The fundamental properties of V389 Cas were determined from the simultaneous analysis of our RV curves together with the TESS light curves. The fitting results indicate that V389 Cas is a semidetached eclipsing binary with masses of$M_1=2.38_{-0.08}^{+0.06}{M}_{\odot }$and$M_2=0.33_{-0.01}^{+0.01}{M}_{\odot }$, and radii of$R_1=2.66_{-0.08}^{+0.06}{R}_{\odot }$and$R_2=2.41_{-0.04}^{+0.03}{R}_{\odot }$. A total of 50 frequency signals are detected from the multifrequency analysis of the residuals of the out-of-eclipse light curves. According to the pulsation constants of two frequencies with an amplitude greater than 1.0 mmag (f₂= 28.3487 day⁻¹andf₃= 25.6069 day⁻¹) and location in the Hertzprung–Russell diagram, the primary component of V389 Cas is a typicalδSct-type pulsator.

We explored the feasibility of using biomechanical simulations to predict altered spinal forces resulting from wearing a back-support exoskeleton (BSE) during repetitive lifting tasks. Twenty (10M, 10F) young, healthy participants completed repetitive lifting task, while wearing a BSE (‘with EXO’) and without wearing a BSE (‘without EXO’). Spinal forces were estimated by applying the BSE torque profile to body kinematics measured in ‘with EXO’ condition, while spinal forces were simulated by applying the same torque profile to body kinematics measured in ‘without EXO’ condition. Simulated compression force was higher than estimated compression force, probably due to lower trunk flexion angle in ‘without EXO’ condition. Such differences were larger among women than among men. However, simulated shear force was comparable with estimated shear force. Future works further need to compare simulated and estimated spinal forces for different BSEs (e.g., soft BSE), asymmetric lifting tasks, and different age group.

We investigated how novices’ perception of exoskeleton usefulness changes with different types of exposure to an exoskeleton; and when the biomechanical benefits and limitations of potential exoskeleton use are presented to them. Twenty young, healthy participants completed this study. The three types of informational exposures to a back-support exoskeleton (BSE) were: (1) Information-based, (2) Virtual Reality (VR)-based, and (3) hands-on experience (lifting a box using the BSE), where users virtually and physically completed various lifting/lowering tasks set at shoulder, waist, and ankle heights in symmetric and asymmetric positions. After every trial in each exposure, perceived usefulness was obtained. Overall, perceived usefulness ratings generally varied with major task variables (load, lift height, and trunk angle). The VR-based exposure appeared to clarify the specific circumstances under which the BSE was perceived to be useful and reduced extreme biases (positive or negative) that individuals may have developed prior to trying on a BSE.