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An anisotropic modelling of hollow porous cylinders under harmonic axial loading is proposed to simulate the in vivo behavior of structural elements of cortical bone called osteons. The peripheral surface of the medium is supposed to be impermeable, except on possible existing cracks. Numerical tests are performed by analytical and finite element methods based on the Biot poroelastic theory. The influence of microcracks on the fluid flow is numerically investigated. The findings show that the existence of peripheral cracks directly modifies the stimulation of the mechano‐sensitive network of the bone. Thus, this study attempts to propose a likely mechanism by which bone can sense changes of the surrounding mechanical environment.

This paper aims to investigate the perception threshold (PT) of electrotactile stimulation under non-steady contact condition (NSCC) which is rarely considered in previous reports mainly because of the difficulty with experimental control. Three factors of NSCC are involved, including the current alternating frequency, the tapping interval of stimulation and the stimulating area of skin. The study is aimed at providing the basic PT data for design and application of wearable and portable electrotactile device.

The up-down method was selected to assess PT, and 72 experimental scenarios were constructed. During the study, we developed an experimental platform with the function of data record and programmable current stimulation. With psychophysical experiment, more than 10,000 data were collected. Furthermore, statics analysis and ANOVA test were opted for exploring the main factor influencing PT.

NSCC has different PTs on each body location, and PT has a positive correlation with frequency. In general, PT in NSCC is significantly lower than that in SCC. In some cases, it can be lower by more than 60 per cent. In addition, women have a lower PT than men across all age groups, and the younger is generally more sensitive than the older in electro-sensation.

Limited factors of NSCC were considered in this study. Contact time and break interval should be investigated in the future work.

The paper includes implications for the development of smart electrotactile device.

This paper fulfills a challenge in assessing the PT under NSCC.

Electric fields (EFs) are known to influence cell and tissue activity. This influence can be due to thermal or non-thermal effects. While the non-thermal effects are still matter of discussion, thermal effects might be detrimental for cell and tissue viability due to thermal damage, this fact being exploited by applications like hyperthermia and tissue ablation. The paper aims to discuss these issues.

In this work the authors investigate the influence of thermal damage in the consolidation of bone formation during electrostimulation (ES). The authors introduce a mathematical model describing the migration of osteoprogenitor cells, the thermal variation, the thermal damage accumulation and the formation of new bone matrix in an injury (fracture) site.

Numerical results are in agreement with experimental data and show that EFs more intense than 7.5 V/cm are detrimental for the viability of osteoprogenitor cells and the formation of new bone.

The model is suitable to conduct dosimetry studies in support of other different ES techniques aimed at improving bone and soft tissues repair.

This paper aims to peruse the influence of second law analysis for electrically conducting fluid of a Casson nanofluid over a wedge. For activation energy, a modified Arrhenius function is used.

The highly non-linear governing equations are developed using similarity transformations and then computed numerically via Keller–Box method.

The influences of emerging parameters on velocity, temperature distribution and concentration of nanoparticle are explained and presented via graphs and tables. Also, the behavior of fluid flow is investigated through the coefficient of skin friction, Nusselt and Sherwood numbers. Results reveal that the velocity profile enhances due to increasing Casson parameter and magnetic parameter, whereas the temperature distribution and concentration of nanoparticle decrease with larger vales of Casson parameter. It is inspected that the concentration boundary layer increases due to activation energy and decreases due to reaction rate and temperature differences.

The authors believe that all the numerical results are original and significant which are used in biomedicine, industrial, electronics and transportation. The results have not been considered elsewhere.