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Introduction: Differentiation of hepatocytes and culture methods have been investigated in dogs as a tool to establish liver transplant and drug metabolism examination systems. However, mass culture techniques for canine hepatocytes (cHep) have not been investigated, and it is necessary to construct a suitable culture system. Recently, a protocol called Bud production has attracted attention, and a mixed culture of human and mouse hepatocytes, stem cells, and artificial blood vessels significantly improved the size and formation ratio of spheroids. The purpose of this study was to investigate and improve the in vitro culture of cHep by mixing canine adipose-derived mesenchymal stem cells (cASCs) and human umbilical vein endothelial cells (HUVECs). Methods: Spheroid formation ratio and histological examination were evaluated among four culture methods, including cHep alone, two-mix (cHep + cASCs and cHep + HUVEC), and three-mix (cHep + HUVEC + cASCs), on days 0, 4, and 7. Expression levels of liver-related genes (ALB, AFP, α1-AT, CDH1, CYP2E1, CYP3A12, and TAT) were evaluated by quantitative real-time polymerase chain reaction (RT-PCR). Protein expression of albumin, vimentin, and von Willebrand Factor (vWF) was investigated to confirm the location of the hepatocytes. Results: The ratio of spheroid formation was 60.2% in the three-mix culture and was significantly improved compared with cHep alone (5.9%) and two-mix; cHep + cASCs (36.2%) and cHep + HUVEC (26.4%) (P

Cell migration is essential in numerous living processes, including embryonic development, wound healing, immune responses, and cancer metastasis. From individual cells to collectively migrating epithelial sheets, the locomotion of cells is tightly regulated by multiple structural, chemical, and biological factors. However, the high complexity of this process limits the understanding of the influence of each factor. Recent advances in materials science, tissue engineering, and microtechnology have expanded the toolbox and allowed the development of biomimetic in vitro assays to investigate the mechanisms of cell migration. Particularly, three-dimensional (3D) hydrogels have demonstrated a superior ability to mimic the extracellular environment. They are therefore well suited to studying cell migration in a physiologically relevant and more straightforward manner than in vivo approaches. A myriad of synthetic and naturally derived hydrogels with heterogeneous characteristics and functional properties have been reported. The extensive portfolio of available hydrogels with different mechanical and biological properties can trigger distinct biological responses in cells affecting their locomotion dynamics in 3D. Herein, we describe the most relevant hydrogels and their associated physico-chemical characteristics typically employed to study cell migration, including established cell migration assays and tracking methods. We aim to give the reader insight into existing literature and practical details necessary for performing cell migration studies in 3D environments.

Body mapping is a visual (drawing) tool, technique and methodological process that has been used by practitioners and researchers in a variety of contexts across the world, including in sexual and reproductive health interventions and research. One of the benefits of body mapping is that it can be used with semi-literate and illiterate populations. In this article, we describe the limitations of traditional body mapping methods and the use of clay as a body mapping medium—a three-dimensional body mapping approach as compared to traditional two-dimensional approaches—within a methodology we call the clay embodiment research method (CERM). This methodology intertwines elements of ethnography, clay body mapping and group work. Its three interdependent components are a form of participant observation, a series of seven themed participatory clay body mapping workshops; and a group interview using photography of the clay works. We discuss the participants' experience in a study of reproductive health knowledge among trafficked women in Nepal in which we used CERM, noting the benefits they said they got from the process, such as developing and sharing knowledge, enjoying learning, allaying fears, promoting self-development, building confidence, enabling problem solving and educating others.

Body mapping is a visual (drawing) tool, technique and methodological process that has been used by practitioners and researchers in a variety of contexts across the world, including in sexual and reproductive health interventions and research. One of the benefits of body mapping is that it can be used with semi-literate and illiterate populations. In this article, we describe the limitations of traditional body mapping methods and the use of clay as a body mapping medium--a three-dimensional body mapping approach as compared to traditional two-dimensional approaches --within a methodology we call the clay embodiment research method (CERM). This methodology intertwines elements of ethnography, clay body mapping and group work. Its three interdependent components are a form of participant observation, a series of seven themed participatory clay body mapping workshops; and a group interview using photography of the clay works. We discuss the participants' experience in a study of reproductive health knowledge among trafficked women in Nepal in which we used CERM, noting the benefits they said they got from the process, such as developing and sharing knowledge, enjoying learning, allaying fears, promoting self-development, building confidence, enabling problem solving and educating others. [ABSTRACT FROM AUTHOR]

Introduction: Three-dimensional (3D) histology analyses are essential to overcome sampling variability and understand pathological differences beyond the dissection axis. We present Path2MR, the first pipeline allowing 3D reconstruction of sparse human histology without an MRI reference. We implemented Path2MR with post-mortem hippocampal sections to explore pathology gradients in Alzheimer's Disease., Methods: Blockface photographs of brain hemisphere slices are used for 3D reconstruction, from which an MRI-like image is generated using machine learning. Histology sections are aligned to the reconstructed hemisphere and subsequently to an atlas in standard space., Results: Path2MR successfully registered histological sections to their anatomical position along the hippocampal longitudinal axis. Combined with histopathology quantification, we found an expected peak of tau pathology at the anterior end of the hippocampus, while amyloid-β displayed a quadratic anterior-posterior distribution., Conclusion: Path2MR, which enables 3D histology using any brain bank dataset, revealed significant differences along the hippocampus between tau and amyloid-β., Competing Interests: Conflicts Declarations of interest: none

Abstract A multi-phase porous media transport model is built using distributed sublimation front approach and fixed grid meshing in order to simulate the freeze drying process. The model is tested numerically in multi-dimensions using 1D, 2D and 3D models. Models are solved for different aspect ratios with different heating methods like surface radiation, surface conduction and volumetric (microwave) heating. The involved critical parameters are discussed comprehensively in the results such as the maximum operating temperature, the maximum sublimation pressure, the total drying time and the overall power consumption. The results show that at low aspect ratios in surface heating technique, the 3D model is mandatory due to the large deviation in the drying time, maximum temperature and maximum pressure with both 2D and 1D models. Comparison between the present model and previous experimental and numerical works has been executed and good agreement has been observed. Highlights • Freeze drying is simulated via multi-phase porous media transport model. • Models are solved for different aspect ratios. • Surface heating and volume heating approaches are investigated. • The 3D model is mandatory at high aspect ratios. [ABSTRACT FROM AUTHOR]

Highlights • The asymptotic solution to the elasticity system in the vicinity of an crack in a 3-D domain is provided with emphasis to the T-stress. • Having this expansion, and using the quasi-dual function method we extract the T-stress from FE solutions. • Numerical examples show the efficiency and accuracy of the methods for the extraction of the edge T-stress. Abstract The T-stress in a three dimensional elastic domain containing a straight crack is considered. First the complete asymptotic expansion in the vicinity of the crack front, including the T-stress, is presented explicitly. Having obtained the asymptotic expansion, we compute the dual solution associated with the T-stress, and prove it must contain logarithmic terms. This dual solution is used to extend the quasi dual function method (QDFM) for the extraction of the T-stress from finite element solutions and express it as a function along the crack front. Since the stress field tends to infinity at the crack front whereas the T-stress remains constant, its extraction from finite element solutions, containing numerical errors, is a non-trivial task. We herein develop accurate and efficient methods for extracting the T-stress function along the crack edge by the QDFM. Numerical examples are provided for the computation of the T-stresses from conventional and high order finite element methods. [ABSTRACT FROM AUTHOR]

While color video endoscopy has enabled wide-field examination of the gastrointestinal tract, it often misses or incorrectly classifies lesions.Many of thesemissed lesions exhibit characteristic three-dimensional surface topographies. An endoscopic system that adds topographical measurements to conventional color imagery could therefore increase lesion detection and improve classification accuracy. We introduce photometric stereo endoscopy (PSE), a technique which allows high spatial frequency components of surface topography to be acquired simultaneously with conventional two-dimensional color imagery.We implement this technique in an endoscopic form factor and demonstrate that it can acquire the topography of small features with complex geometries and heterogeneous optical properties. PSE imaging of ex vivo human gastrointestinal tissue shows that surface topography measurements enable differentiation of abnormal shapes from surrounding normal tissue. Together, these results confirm that the topographical measurements can be obtained with relatively simple hardware in an endoscopic form factor, and suggest the potential of PSE to improve lesion detection and classification in gastrointestinal imaging. [ABSTRACT FROM AUTHOR]

We consider a Dirichlet boundary-value problem for the three-dimensional convection-diffusion equations with constant coefficients in the unit cube. A high order compact finite difference scheme is constructed on a 19-point stencil using the Steklov averaging operators. We prove that the finite difference scheme converges in discrete W 2m (ω)-norm with the convergence rate O(hs-m), where the real parameter s satisfies the condition max(1.5, m) < s ≤ m + 4, m = 0, 1, 2, and the exact solution belongs to the Sobolev space W2s (Ω). [ABSTRACT FROM AUTHOR]

Abstract: The nearly singular integrals occur in the boundary integral equations when the source point is close to an integration element (as compared to its size) but not on the element. In this paper, the concept of a relative distance from a source point to the boundary element is introduced to describe possible influence of the singularity of the integrals. Then a semi-analytical algorithm is proposed for evaluating the nearly strongly singular and hypersingular integrals in the three-dimensional BEM. By using integration by parts, the nearly singular surface integrals on the elements are transformed to a series of line integrals along the contour of the element. The singular behavior, which appears as factor, is separated from remaining regular integrals. Consequently standard numerical quadrature can provide very accurate evaluation of the resulting line integrals. The semi-analytical algorithm is applied to analyzing the three-dimensional elasticity problems, such as very thin-walled structures. Meanwhile, the displacements and stresses at the interior points very close to its bounding surface are also determined efficiently. The results of the numerical investigation demonstrate the accuracy and effectiveness of the algorithm. [Copyright &y& Elsevier]

Analysis of the dermo-epidermal surface in three-dimensions has great value in evaluating cosmetics. One approach is based on the active contour model, which is used extensively in computer vision and image processing applications, particularly for local object boundaries with closed curve form. The dermo-epidermal surface, however, is a plane with open form. We have developed a method of automatically extracting the dermo-epidermal surface from volumetric confocal microscopic images, as well as constructing a 3D visual model of the surface by using the geometric information contained in the control points. Our method is a 3D extension of the active contour model, so we call it the active open surface model (AOSM). The initial surface for AOSM is an open curve plane, guided by a 3D internal force, a 3D external constraint force, and a 3D image force, which pull it towards the objective surface. The proposed tecnique has been applied to extract actual dermo-epidermal surface in the given volumetric confocal microscopic images. [ABSTRACT FROM AUTHOR]