Slip and hall current effects on Jeffrey fluid suspension flow in a peristaltic hydromagnetic blood micropump

The magnetic properties of blood allow it to be manipulated with an electromagnetic field. Electromagnetic blood flow pumps are a robust technology which provide more elegant and sustainable performance compared with conventional medical pumps. Blood is a complex multi-phase suspension with non-Newtonian characteristics which are significant in micro-scale transport. Motivated by such applications, in the present article a mathematical model is developed for magnetohydrodynamic (MHD) pumping of blood in a deformable channel with peristaltic waves. A Jeffery’s viscoelastic formulation is employed for the rheology of blood. A twophase fluid-particle (“dusty”) model is utilized to better simulate suspension characteristics (plasma and erythrocytes). Hall current and wall slip effects are incorporated to achieve more realistic representation of actual systems. A two-dimensional asymmetric channel with dissimilar peristaltic wave trains propagating along the walls is considered. The governing conservation equations for mass, fluid and particle momentum are formulated with appropriate boundary conditions. The model is simplified using of long wavelength and creeping flow approximations. The model is also transformed from the fixed frame to the wave frame and rendered non-dimensional. Analytical solutions are derived. The resulting boundary value problem is solved analytically and exact expressions are derived for the fluid velocity, particulate velocity, fluid/particle fluid and particulate volumetric flow rates, axial pressure gradient, pressure rise and skin friction distributions are evaluated in detail. Increasing Hall current parameter reduces bolus growth in the channel, particle phase velocity and pressure difference in the augmented pumping region whereas it increases fluid phase velocity, axial pressure gradient and pressure difference in the pumping region. Increasing the hydrodynamic slip parameter accelerates both particulate and fluid phase flow at and close to the channel walls, enhances wall skin friction, boosts pressure difference in the augmented pumping region and increases bolus magnitudes. Increasing viscoelastic parameter (stress relaxation time to retardation time ratio) decelerates the fluid phase flow, accelerates the particle phase flow, decreases axial pressure gradient, elevates pressure difference in the augmented pumping region and reduces pressure difference in the pumping region. Increasing drag particulate suspension parameter decelerates the particle phase velocity, accelerates the fluid phase velocity, strongly elevates axial pressure gradient and reduces pressure difference (across one wavelength) in the augmented pumping region. Increasing particulate volume fraction density enhances bolus magnitudes in both the upper and lower zones of the channel and elevates pressure rise in the augmented pumping region

Effect of Stop-X Injury Prevention Program on LESS and Proprioception of Child ‎Soccer Players with Dynamic Knee Valgus

Purpose: The risk of anterior cruciate ligament (ACL) injuries in childhood has increased in recent decades and could be a major threat to a child's sports career. An increased risk of ACL injury is associated with dynamic knee valgus (DKV). Therefore, this study aimed to analyze the effect of an ACL injury protocol on the LESS, proprioception, and DKV of child soccer players. Methods: In this study, thirty male football players with DKV (mean ± SD: age 11.40 ± .72 years, weight 36.62 ± 4.68 kg, height 141.10 ± 3.98 m) were randomly assigned into two groups: control (n=15) and training (n=15). Single-leg landing, LESS, and knee joint proprioception tests were administered before and after the implementation of the training protocol. After identifying the variables, the training group performed the injury proprioception program for eight weeks, with three training sessions each lasting 20–25 minutes per week. The control group continued their normal warm-up routine. To examine the difference between the pre-test and post-test, repeated measures ANOVA was conducted using SPSS 26 software with a significance level of 0.05. Results: The results of the research showed that after eight weeks of the injury prevention program, there was a significant improvement in reducing the valgus angle of the knee (p=0.005, F=9.369, η²=0.251), reducing the LESS scores (p=0.002, F=12.374, η²=0.306) and improving proprioception (p=0.003, F=10.251, η²=0.268). Conclusion: According to the results of the research, it can be concluded that Stop-X injury prevention program can lead to improvements in knee valgus pattern, LESS and proprioception in child soccer players. Using the results of this research is recommended to soccer coaches and training experts

CFD simulation of nanofluid forced convection inside a three-dimensional annulus by two-phase mixture approach: Heat transfer and entropy generation analyses

The final publication is available at Elsevier via https://dx.doi.org/10.1016/j.ijmecsci.2018.08.002 © 2018. This manuscript version is made available under the CC-BY-NC-ND 4.0 license https://creativecommons.org/licenses/by-nc-nd/4.0/The behavior of water–Al2O3 nanofluid inside the three-dimensional horizontal concentric annulus is investigated by the two-phase mixture procedure regarding the first and second laws of thermodynamics. The annulus walls are subjected to constant temperature boundary condition. Heat transfer and entropy generation rates, nanoparticle distribution, skin friction coefficient, and temperature distribution are evaluated at different concentrations and Reynolds numbers. The results show that nanoparticle concentration at the bottom of annulus and the upper side of inner cylinder is greater than other regions. In addition, the heat transfer and thermal entropy generation rates increase with increment of concentration and Reynolds number. Moreover, the lowest and highest thermal entropy generation rates happen in the annulus central part and near the walls, respectively. Bejan number is very close to 1 at all cases under study, which shows the dominance of thermal entropy generation

Vector-borne pathogens in dogs of different regions of Iran and Pakistan

Canine vector-borne diseases (CVBDs) are highly prevalent in tropical and subtropical countries, mainly due to favorable climate conditions and reduced adoption of preventive measures. This study aimed to provide a comprehensive overview on the prevalence of CVBDs in Iran and Pakistan where limited data are available. Blood samples were collected from 403 dogs from six provinces in Iran and Pakistan to assess the presence of pathogen DNA (i.e., Anaplasma spp., Coxiella burnetii, Ehrlichia spp., Rickettsia spp., Babesia spp., Hepatozoon spp., filarioids, and Leishmania spp.). Sera were also screened by an immunofluorescence antibody test for the detection of antibodies against Leishmania infantum. In total, 46.9% of dogs scored positive to Hepatozoon canis being the most frequently detected (41.4%), followed by Anaplasma platys (6.4%), Ehrlichia canis (3.4%), Rickettsia spp. (2.2%), Babesia vogeli (1.0%), and L. infantum (0.3%). A seroprevalence of 9.6% to anti-L. infantum IgG was also recorded. Data reported herein demonstrate that dogs from Iran and Pakistan are at a high risk of CVBDs, particularly of canine hepatozoonosis. Effective control strategies are advocated for minimizing the risk of infection in animals and humans, also in consideration of the zoonotic potential of some pathogens detected