Article
Mechanics
N. Tofighi, J. J. Feng, M. Yildiz, A. Suleman
Summary: A two-dimensional incompressible smoothed particle hydrodynamics scheme was presented for long-term sedimentation of rising or falling particulates in Newtonian fluids. It was validated by simulating the sedimentation of a single elliptic disc and used to simulate the sedimentation of an elliptic disc subject to an external electric field parallel to the gravitational field. The results showed that the final sedimentation orientation of the ellipse depended on a combination of permittivity ratio and electric field intensity, ranging from horizontal to vertical. An increase in electric field intensity and permittivity ratio led to vertical sedimentation, and the presence of electric field resulted in faster descent of the ellipse as the channels grew wider, regardless of its initial orientation.
INTERNATIONAL JOURNAL OF MULTIPHASE FLOW
(2021)
Article
Chemistry, Physical
J. Hemauer, M. Qiu, J. J. Feng, J. -C. Loudet
Summary: The study found that particle rotation accelerates capillary attraction between particles, and the effect is more significant with higher viscosity mismatch. Furthermore, the analysis shows that the translational drag force on a rotating particle is always less than its non-rotating counterpart.
EUROPEAN PHYSICAL JOURNAL E
(2021)
Article
Biochemistry & Molecular Biology
Clinton H. Durney, James J. Feng
Summary: This study explores the roles of cellular forces during the formation of the salivary gland in Drosophila embryos using a novel three-dimensional vertex model. Different myosin pools were found to play distinct roles in the invagination process, leading to the formation of a model that agrees with experimental observations.
Correction
Chemistry, Physical
S. M. Amin Arefi, Cheng Wei Tony Yang, Don D. Sin, James J. Feng
EUROPEAN PHYSICAL JOURNAL E
(2021)
Article
Chemistry, Physical
S. M. Amin Arefi, Cheng Wei Tony Yang, Don D. Sin, James J. Feng
Summary: Leukocytes can traverse endothelial cells through transcellular and paracellular routes, with the tenetaxis hypothesis suggesting they choose the path of least mechanical resistance. Numerical simulations on human lung endothelium parameters confirm that transcellular diapedesis requires more force, aligning with experimental results. Manipulating the strength between the two routes can affect the preferred pathway, supporting the hypothesis.
EUROPEAN PHYSICAL JOURNAL E
(2021)
Article
Computer Science, Interdisciplinary Applications
Lei Li, Jiaqi Zhang, Zelai Xu, Y-N Young, James J. Feng, Pengtao Yue
Summary: This article proposes a finite-element method for computing flows involving a fluid-hydrogel interface. The hydrogel is treated as a poroelastic material and the interfacial deformation is coupled with the fluid and solid governing equations. Numerical tests show excellent agreement between the results obtained using this method and analytical solutions in various flow problems.
JOURNAL OF COMPUTATIONAL PHYSICS
(2022)
Article
Physics, Fluids & Plasmas
Zelai Xu, Jiaqi Zhang, Yuan-Nan Young, Pengtao Yue, James J. Feng
Summary: We studied the boundary conditions at the interface between a hydrogel and a clear fluid and proposed three sets of boundary conditions that link the velocity and stress across the interface. We tested and compared these boundary conditions using several flow problems and recommend one set of boundary conditions for computing the flow and deformation of hydrogels. Benchmark experiments are suggested for validation.
PHYSICAL REVIEW FLUIDS
(2022)
Article
Biophysics
Z. Wang, R. Lu, W. Wang, F. B. Tian, J. J. Feng, Y. Sui
Summary: We propose a three-dimensional computational model to simulate the transient deformation of suspended cancer cells flowing through a constricted microchannel. The cell is modeled as a liquid droplet enclosed by a viscoelastic membrane, with its nucleus as a smaller stiffer capsule. The results show that a viscoelastic cell membrane model with the membrane viscosity depending on its mode of deformation can achieve excellent agreement with experimental results on human leukemia cells.
BIOMECHANICS AND MODELING IN MECHANOBIOLOGY
(2023)
Article
Developmental Biology
Dina J. Ashour, Clinton H. Durney, Vicente J. Planelles-Herrero, Tim J. Stevens, James J. Feng, Katja Roper
Summary: During embryogenesis, the coordination of large-scale changes in tissue primordia is important for development. In Drosophila, supracellular actomyosin cables, composed of the protein Zasp52, are involved in this coordination, particularly in regions such as the ventral midline and the boundary of the salivary gland placode. Zasp52 interacts with junctional components and actomyosin regulators, and its absence leads to severe embryonic defects. These findings suggest that Zasp52-containing cables aid in insulating morphogenetic changes from one another during embryogenesis.
Article
Multidisciplinary Sciences
Zelai Xu, Pengtao Yue, James J. Feng
Summary: Albuminuria occurs when albumin leaks into the urine, and the mechanism behind it is not well understood. A gel-compression hypothesis suggests that compression of the glomerular basement membrane (GBM) acts as a barrier, but it fails to explain the reduction in filtration flux and thickening of the GBM. A second mechanism involving constriction of flow area at the slit diaphragm must also be considered. By combining these two mechanisms, the poroelastic model validates the hypothesis and explains the in vivo features of albuminuria.
JOURNAL OF THE ROYAL SOCIETY INTERFACE
(2023)
Proceedings Paper
Computer Science, Interdisciplinary Applications
Alzbeta Bohinikova, Iveta Jancigova, Ivan Cimrak, James J. Feng
Summary: This work presents a computational model of elastic double cluster and focuses on the adhesion between the two cells. The model is validated through experimental and computational simulations, and can be used as a building block in future computational studies.
BIOINFORMATICS AND BIOMEDICAL ENGINEERING, PT II
(2022)
Article
Biochemical Research Methods
James J. Feng, Sarah Hedtrich
Summary: Organ-on-chip devices (OoCs) provide a more detailed understanding of (patho)physiological processes than traditional tissue models. However, the current design approach lacks systematic scaling, limiting the predictive value. The proposed similarity scaling approach can significantly improve the design and operation of OoCs.
Article
Physics, Fluids & Plasmas
J-C Loudet, A. Choudhury, M. Qiu, J. J. Feng
Summary: We present numerical simulations of a particle trapped at the isotropic-nematic liquid crystal interface. The results show that the response of the system is driven by the existence of an anchoring conflict at the contact line. Drag forces exerted on the particle moving along the interface are also computed.
Article
Physics, Fluids & Plasmas
Mingfeng Qiu, James J. Feng, Jean-Christophe Loudet
Summary: A phase-field model is proposed to study interfacial flows of nematic liquid crystals, incorporating a tensor order parameter and a phase-field formalism to accurately describe the dynamics of drop retraction. Results show that steady-state drop deformation and the clearance between defects and drop surface both linearly depend on the elastocapillary number.
Article
Physics, Fluids & Plasmas
Anjishnu Choudhury, Mohar Dey, Harish N. Dixit, James J. Feng
Summary: This study aims to elucidate the hydrodynamic mechanisms by which the loss of membrane-associated mucins causes premature tear-film rupture, demonstrating a strong effect of the elevated van der Waals attraction on precipitating tear-film breakup. The change in boundary condition on the cornea has a relatively minor role in comparison.
