geometry module of comsol multiphysics  (COMSOL Inc)

Journal: bioRxiv

Article Title: Fluid forces control structural remodeling of blind-ended lymphatic microvessels

doi: 10.1101/2025.04.14.648799

Figure Lengend Snippet: Engineered blind-ended lymphatic microvessel. A) Schematic of the novel PDMS-based Static microdevice and subsequent steps to generate a lymphatic vessel. A 250-μm-diameter wire is placed within the device terminating at the midplane of the central ECM chamber. Collagen-based hydrogel is pipetted into the central chamber via the lateral gel ports. Upon gel polymerization, the wire is removed to expose a blind-ended hollow lumen structure. The templated lumen is then seeded with human dermal lymphatic endothelial cells (HDLECs) to create a microvessel. PDMS layers are represented as transparent gray, glass slide as blue, collagen as yellow, cell culture media as pink, and HDLECs as green. Black dashed region depicts the top view of the central gel chamber with the engineered microtissue fully constituted. Scale bar is 1 mm. B) Phase-contrast images corresponding to steps in A to illustrate workflow resulting in a representative blind-ended lymphatic vessel encased in 3 mg mL -1 collagen (COL). Scale bars are 500 μm. C) Photograph of Static microfluidic device. Scale bar is 5 mm. D) Confocal z -projection of a representative blind-ended lymphatic microvessel stained for junction protein VE-Cadherin (antibody, magenta) and nuclei (DAPI, blue). E) Orthogonal views to demonstrate a patent, perfusable microvessel with a monolayer of HDLECs: x-y , x-z , and y-z cross sections (counterclockwise from upper left). Scale bars in D and E are 200 μm. F) 3-D render of a blind-ended lymphatic vessel from confocal z -stack. Major tick marks are 200 μm.

Article Snippet: The 3-D geometry of the microvessel and device were constructed in COMSOL Multiphysics 6.2 with precise dimensions.

Techniques: Cell Culture, Staining

Journal: bioRxiv

Article Title: Fluid forces control structural remodeling of blind-ended lymphatic microvessels

doi: 10.1101/2025.04.14.648799

Figure Lengend Snippet: Interstitial flow initiates and sustains lymphangiogenesis independent of VEGF-C. A) Matrix of representative lymphatic microvessels subjected to the four experimental conditions and fixed at Day 4. Images are confocal z -projections of vessels stained for F-actin (phalloidin, green) and nuclei (DAPI, blue). White arrows indicate the direction of physiologically relevant interstitial flow (IF). Scale bars are 200 μm. B) Quantification of sprouting area per vessel as a percentage of total vessel surface area ( N = 4 or 5 vessels). C) Invasion depth of individual sprouting LECs into the surrounding ECM measured from the vessel surface ( N > 20 cells for – Flow conditions, and N > 400 cells for +Flow conditions). Data are expressed as mean ± SD. One-way ANOVA was performed with Tukey pairwise comparisons, where * indicates p -value < 0.05, ** < 0.01, *** < 0.001, and **** < 0.0001.

Article Snippet: The 3-D geometry of the microvessel and device were constructed in COMSOL Multiphysics 6.2 with precise dimensions.

Techniques: Staining

Journal: bioRxiv

Article Title: Fluid forces control structural remodeling of blind-ended lymphatic microvessels

doi: 10.1101/2025.04.14.648799

Figure Lengend Snippet: Selective lymphangiogenesis occurs at the blind-end due to elevated local transverse velocity. A) Confocal z -projection images of vessels were binarized, and sprouts were isolated. A map divides a representative vessel into five zones (Zones 0–4) depicted by red dashed lines corresponding to 250-μm vessel segments normal to the vessel surface. Scale bars are 200 μm. B) Heat map of transverse flow velocity across the lymphatic vessel surface from finite element analysis (FEA). Velocity is greatest at the blind end due to the orientation of the vessel pointing towards the source of flow. C) Transverse velocity and intraluminal shear stress from FEA plotted along the length of the vessel, given axial symmetry. Demarcated zones highlight varying flow velocity and shear stress for different regions of the same microvessel due to the blind end. D and E) Sprouting area per zone normalized as a percentage of respective vessel surface area within each zone, with and without VEGF-C ( N = 4 or 5 vessels). Sprouting area— as a metric for lymphangiogenic activity—strongly correlates with transvascular flow velocity and negatively correlates with intraluminal shear stress. Data are expressed as mean ± standard deviation. Two-way ANOVA was performed with Tukey pairwise comparisons, where * indicates p -value < 0.05, ** < 0.01, and *** < 0.001.

Article Snippet: The 3-D geometry of the microvessel and device were constructed in COMSOL Multiphysics 6.2 with precise dimensions.

Techniques: Isolation, Shear, Activity Assay, Standard Deviation

Journal: bioRxiv

Article Title: Fluid forces control structural remodeling of blind-ended lymphatic microvessels

doi: 10.1101/2025.04.14.648799

Figure Lengend Snippet: Lymphangiogenic sprouts are guided by interstitial flow (IF) streamlines. A) Magnitude of IF velocity and directional streamlines (white lines) within the collagen gel are plotted for a theoretical lymphatic vessel in our Flow device by finite element analysis (FEA). B) Confocal z -projection of a representative microvessel under the Flow condition with FEA streamlines superimposed. Scale bar is 200 μm. Inset is an individual sprouting cell, depicting the angular difference (0 sprout ) between the major axis of the cell (dashed white arrow) and the streamline at the centroid location of the cell (white line). Inset scale bar is 50 μm. C) For Flow and Flow+VEGF-C conditions, the major axes of individual sprouting cells are plotted as green arrows and mapped to their respective location within the collagen matrix ( N = 4 vessels per condition). Streamlines are displayed as black lines. D) Probability-normalized polar histograms of 0 sprout for individual cells in panel C, where 0° is defined as perfectly aligned to the streamline ( N > 300 cells for Flow, and N > 1000 cells for Flow+VEGF-C). Mean resultant vectors denoted as red lines. On average, sprouting LECs invade the ECM collinearly with streamlines, antiparallel to the direction of IF.

Article Snippet: The 3-D geometry of the microvessel and device were constructed in COMSOL Multiphysics 6.2 with precise dimensions.

Techniques:

Journal: Biomechanics and Modeling in Mechanobiology

Article Title: Homogenized multiscale modelling of an electrically active double poroelastic material representing the myocardium

doi: 10.1007/s10237-025-01931-0

Figure Lengend Snippet: COMSOL Multiphysics 3D geometries showing the direction of the myocyte elongation as well as the direction of the electrical conductances

Article Snippet: Fig. 3 COMSOL Multiphysics geometry for the electrostatic cell problems We use the following conductivity tensors obtained from Roth ( ); Sachse et al. ( ) for the transversal and longitudinal conductivities in the myocyte and extracellular matrix 85 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} {\textsf{G}}_i=\begin{pmatrix} 0.047 & 0 \\ 0 & 0.469 \end{pmatrix}, \quad \text{ and } \quad {\textsf{G}}_e=\begin{pmatrix} 0.214 & 0 \\ 0 & 0.375 \end{pmatrix}.

Techniques:

Journal: Biomechanics and Modeling in Mechanobiology

Article Title: Homogenized multiscale modelling of an electrically active double poroelastic material representing the myocardium

doi: 10.1007/s10237-025-01931-0

Figure Lengend Snippet: COMSOL Multiphysics geometry for the electrostatic cell problems

Article Snippet: Fig. 3 COMSOL Multiphysics geometry for the electrostatic cell problems We use the following conductivity tensors obtained from Roth ( ); Sachse et al. ( ) for the transversal and longitudinal conductivities in the myocyte and extracellular matrix 85 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} {\textsf{G}}_i=\begin{pmatrix} 0.047 & 0 \\ 0 & 0.469 \end{pmatrix}, \quad \text{ and } \quad {\textsf{G}}_e=\begin{pmatrix} 0.214 & 0 \\ 0 & 0.375 \end{pmatrix}.

Techniques:

Journal: Biomechanics and Modeling in Mechanobiology

Article Title: Homogenized multiscale modelling of an electrically active double poroelastic material representing the myocardium

doi: 10.1007/s10237-025-01931-0

Figure Lengend Snippet: COMSOL Multiphysics geometries for the double poroelastic material

Article Snippet: Fig. 3 COMSOL Multiphysics geometry for the electrostatic cell problems We use the following conductivity tensors obtained from Roth ( ); Sachse et al. ( ) for the transversal and longitudinal conductivities in the myocyte and extracellular matrix 85 \documentclass[12pt]{minimal} \usepackage{amsmath} \usepackage{wasysym} \usepackage{amsfonts} \usepackage{amssymb} \usepackage{amsbsy} \usepackage{mathrsfs} \usepackage{upgreek} \setlength{\oddsidemargin}{-69pt} \begin{document}$$\begin{aligned} {\textsf{G}}_i=\begin{pmatrix} 0.047 & 0 \\ 0 & 0.469 \end{pmatrix}, \quad \text{ and } \quad {\textsf{G}}_e=\begin{pmatrix} 0.214 & 0 \\ 0 & 0.375 \end{pmatrix}.

Techniques: