scholarly journals 3D print material study to reproduce the function of pig heart tissue

2021 ◽  
Vol 29 ◽  
pp. 27-34
Author(s):  
Jung-Hun Kim ◽  
Chun-Kyu Park ◽  
Ji-Eun Park ◽  
Jong-Min Lee
Keyword(s):  
Three Dimensional ◽  
Heart Tissue ◽  
Elastic Force ◽  
Elastic Coefficient ◽  
Anatomical Structures ◽  
3D Print ◽  
Average Value ◽  
Print Material ◽  
Coefficient Of Elasticity ◽  
Silicone Sample

BACKGROUND: Three-dimensional (3D) printing technology for heart simulation can be represented as complex anatomical structures, and objective information can be provided. OBJECTIVE: We studied 3D print material to find a material with the same elastic coefficient as pig elastic coefficient. METHODS: Pig heart sample, Agilus sample, Tango sample, TPU sample, and silicone sample were studied. The elastic coefficient of each specimen was measured using an elastic coefficient measuring instrument. The analysis was performed using the average value of ten specimens of the same size. We suggested an equation to find the elastic coefficient of material by the thickness using the elastic coefficient of Agilus, Tango, and silicone. RESULTS: The sample with similar elasticity to the pig sample did not show the same coefficient of elasticity at the same sample size. In Tango, the 0.5 mm high elastic force was about 3 times higher than the pig sample 7 mm elastic force. CONCLUSIONS: The study was conducted using 3D print material and silicone which can reproduce the elasticity of pig heart. However, no material is currently available to reproduce pig heart sample of the same size. However, if the heart is developed considering only elasticity, it can be sufficiently reproduced using the research results.

scholarly journals Computational Analysis to Factor Wind into the Design of an Architectural Environment

2015 ◽  
Vol 2015 ◽  
pp. 1-10 ◽  
Author(s):  
Hassam Nasarullah Chaudhry ◽  
John Kaiser Calautit ◽  
Ben Richard Hughes
Keyword(s):  
Fluid Dynamics ◽  
Power Generation ◽  
Computational Fluid Dynamics ◽  
Three Dimensional ◽  
Numerical Data ◽  
Navier Stokes ◽  
Windward Side ◽  
Average Value ◽  
Continuity Equations ◽  
Prevailing Wind Direction

The effect of wind distribution on the architectural domain of the Bahrain Trade Centre was numerically analysed using computational fluid dynamics (CFD). Using the numerical data, the power generation potential of the building-integrated wind turbines was determined in response to the prevailing wind direction. The three-dimensional Reynolds-averaged Navier-Stokes (RANS) equations along with the momentum and continuity equations were solved for obtaining the velocity and pressure field. Simulating a reference wind speed of 6 m/s, the findings from the study quantified an estimate power generation of 6.4 kW indicating a capacity factor of 2.9% for the benchmark model. At the windward side of the building, it was observed that the layers of turbulence intensified in inverse proportion to the height of the building with an average value of 0.45 J/kg. The air velocity was found to gradually increase in direct proportion to the elevation with the turbine located at higher altitude receiving maximum exposure to incoming wind. This work highlighted the potential of using advanced computational fluid dynamics in order to factor wind into the design of any architectural environment.

scholarly journals Lobectomy for lung cancer with a displaced left B1 + 2 and an anomalous pulmonary vein: a case report

2021 ◽  
Vol 16 (1) ◽  
Author(s):  
Shinichi Sakamoto ◽  
Hiromitsu Takizawa ◽  
Naoya Kawakita ◽  
Akira Tangoku
Keyword(s):  
Computed Tomography ◽  
Lung Cancer ◽  
Pulmonary Vein ◽  
Three Dimensional ◽  
Lower Lobe ◽  
Rare Condition ◽  
3D Ct ◽  
Anatomical Structures ◽  
Case Presentation ◽  
Anomalous Pulmonary Vein

Abstract Background A displaced left B1 + 2 accompanied by an anomalous pulmonary vein is a rare condition involving complex structures. There is a risk of unexpected injuries to bronchi and blood vessels when patients with such anomalies undergo surgery for lung cancer. Case presentation A 59-year-old male with suspected lung cancer in the left lower lobe was scheduled to undergo surgery. Chest computed tomography revealed a displaced B1 + 2 and hyperlobulation between S1 + 2 and S3, while the interlobar fissure between S1 + 2 and S6 was completely fused. Three-dimensional computed tomography (3D-CT) revealed an anomalous V1 + 2 joining the left inferior pulmonary vein and a branch of the V1 + 2 running between S1 + 2 and S6. We performed left lower lobectomy via video-assisted thoracic surgery, while taking care with the abovementioned anatomical structures. The strategy employed in this operation was to preserve V1 + 2 and confirm the locations of B1 + 2 and B6 when dividing the fissure. Conclusion The aim of the surgical procedure performed in this case was to divide the fissure between S1 + 2 and the inferior lobe to reduce the risk of an unexpected bronchial injury. 3D-CT helps surgeons to understand the stereoscopic positional relationships among anatomical structures.

Analysis of trigonometric chaotic sequence by proposing an index-based bit level scrambling image encryption

2021 ◽  
pp. 2150406
Author(s):  
Wanbo Yu ◽  
Hao Wang
Keyword(s):  
Chaotic Map ◽  
Three Dimensional ◽  
Correlation Coefficients ◽  
Chaotic Sequence ◽  
Binary Number ◽  
Encryption Scheme ◽  
Binary Matrix ◽  
Binary Images ◽  
Average Value ◽  
Research Fields

Chaotic map is applied to numerous research fields, such as encryption of data and information. In this paper, a novel bit-level scrambling encryption based on three-dimensional trigonometric chaotic sequence is proposed. This encryption is operated on grayscale images because pixel value of which is between 0 and 255, which can be converted into 8-bit binary number, then each image can be converted into eight binary images. Combine binary images a three-dimensional matrix as input, which have three index values width, height, and page. Generate three numbers by the chaotic sequence to locate the value of the matrix need to be changed. After the value is located, change its value 0 to 1 or 1 to 0, this is the basic encryption scheme. This paper makes a three-dimensional binary matrix with 32 images to test the encryption scheme, and get average value of images’ number of pixel change rate at 0.9603, unified averaged change intensity at 31.27%, information entropy at 7.9891, also the histograms. And correlation coefficients of each pixel from three directions are small. There are comparisons with other encryptions too. The key space of this encryption is more than 10[Formula: see text].

scholarly journals Performance of Cone Beam Computed Tomography Systems in Visualizing the Cortical Plate in 3D Image Reconstruction: An In Vitro Study

2018 ◽  
Vol 12 (1) ◽  
pp. 586-595 ◽  
Author(s):  
Abbas Shokri ◽  
Mohammad Reza Jamalpour ◽  
Amir Eskandarloo ◽  
Mostafa Godiny ◽  
Payam Amini ◽  
...  
Keyword(s):  
Image Reconstruction ◽  
3D Reconstruction ◽  
Cortical Bone ◽  
Three Dimensional ◽  
Cortical Plate ◽  
3D Image ◽  
Bone Thickness ◽  
Anatomical Structures ◽  
3D Image Reconstruction ◽  
Dental Procedures

Introduction: Cortical bone is an important anatomical structure and its thickness needs to be determined prior to many dental procedures to ensure treatment success. Imaging modalities are necessarily used in dentistry for treatment planning and dental procedures. Three-dimensional image reconstruction not only provides visual information but also enables accurate measurement of anatomical structures; thus, it is necessarily required for maxillofacial examination and in case of skeletal problems in this region. Aims: This study aimed to assess the ability of three Cone Beam Computed Tomography (CBCT) systems including Cranex 3D, NewTom 3G and 3D Promax for Three-Dimensional (3D) image reconstruction of the cortical plate with variable thicknesses. Methods: Depending on the cortical bone thickness, samples were evaluated in three groups of ≤ 0. 5 mm, 0.6 -1 mm and 1.1-1.5 mm cortical bone thickness. The CBCT scans were obtained from each sample using three systems, their respective FOVs, and 3D scans were reconstructed using their software programs. Two observers viewed the images twice with a two-week interval. The ability of each system in the 3D reconstruction of different thicknesses of cortical bone was determined based on its visualization on the scans. The data were analyzed using SPSS and Kappa test. Results: The three systems showed the greatest difference in the 3D reconstruction of cortical bone with < 0.5 mm thickness. Cranex 3D with 4×6 cm2 FOV had the highest and 3D Promax with 8×8 cm2 FOV had the lowest efficacy for 3D reconstruction of cortical bone. Cranex 3D with 4×6 cm2 and 6×8 cm2 FOVs and NewTom 3G with 5×5 cm2 and 8×5 cm2 FOVs showed significantly higher efficacy for 3D reconstruction of cortical bone with 0.6-1mm thickness while 3D Promax followed by NewTom 3G with 8×8 cm2 FOV had the lowest efficacy for this purpose. Conclusion: Most CBCT systems have high efficacy for 3D image reconstruction of cortical bone with thicknesses over 1 mm while they have poor efficacy for image reconstruction of cortical bone with less than 0.5 mm thickness. Thus, for accurate visualization of anatomical structures on CBCT scans, systems with smaller FOVs and consequently smaller voxel size are preferred.

scholarly journals 3-D image-based numerical computations of snow permeability: links to specific surface area, density, and microstructural anisotropy

2012 ◽  
Vol 6 (5) ◽  
pp. 939-951 ◽  
Author(s):  
N. Calonne ◽  
C. Geindreau ◽  
F. Flin ◽  
S. Morin ◽  
B. Lesaffre ◽  
...  
Keyword(s):  
Specific Surface ◽  
Surface Area ◽  
Specific Surface Area ◽  
Three Dimensional ◽  
Analytical Models ◽  
Simple Relationship ◽  
Snow Density ◽  
Average Value ◽  
Wide Range ◽  
Snow Samples

Abstract. We used three-dimensional (3-D) images of snow microstructure to carry out numerical estimations of the full tensor of the intrinsic permeability of snow (K). This study was performed on 35 snow samples, spanning a wide range of seasonal snow types. For several snow samples, a significant anisotropy of permeability was detected and is consistent with that observed for the effective thermal conductivity obtained from the same samples. The anisotropy coefficient, defined as the ratio of the vertical over the horizontal components of K, ranges from 0.74 for a sample of decomposing precipitation particles collected in the field to 1.66 for a depth hoar specimen. Because the permeability is related to a characteristic length, we introduced a dimensionless tensor K*=K/res2, where the equivalent sphere radius of ice grains (res) is computed from the specific surface area of snow (SSA) and the ice density (ρi) as follows: res=3/(SSA×ρi. We define K and K* as the average of the diagonal components of K and K*, respectively. The 35 values of K* were fitted to snow density (ρs) and provide the following regression: K = (3.0 &amp;pm; 0.3) res2 exp((−0.0130 &amp;pm; 0.0003)ρs). We noted that the anisotropy of permeability does not affect significantly the proposed equation. This regression curve was applied to several independent datasets from the literature and compared to other existing regression curves or analytical models. The results show that it is probably the best currently available simple relationship linking the average value of permeability, K, to snow density and specific surface area.

Whole-Heart Tissue Engineering: Use of Three-Dimensional Matrix Scaffolds

2014 ◽  
pp. 215-237
Author(s):  
Hug Aubin ◽  
Jörn Hülsmann ◽  
Antonio Pinto ◽  
Artur Lichtenberg ◽  
Payam Akhyari
Keyword(s):  
Tissue Engineering ◽  
Three Dimensional ◽  
Heart Tissue ◽  
Dimensional Matrix ◽  
Whole Heart

scholarly journals Effect of Selected Commercial Plasticizers on Mechanical, Thermal, and Morphological Properties of Poly(3-hydroxybutyrate)/Poly(lactic acid)/Plasticizer Biodegradable Blends for Three-Dimensional (3D) Print

Materials ◽  
2018 ◽  
Vol 11 (10) ◽  
pp. 1893 ◽  
Author(s):  
Přemysl Menčík ◽  
Radek Přikryl ◽  
Ivana Stehnová ◽  
Veronika Melčová ◽  
Soňa Kontárová ◽  
...  
Keyword(s):  
Mechanical Properties ◽  
Lactic Acid ◽  
Thermal Properties ◽  
Three Dimensional ◽  
Poly Lactic Acid ◽  
Mechanical And Thermal Properties ◽  
Modulated Differential Scanning Calorimetry ◽  
3D Print ◽  
3D Printed ◽  
Biodegradable Blends

This paper explores the influence of selected commercial plasticizers structure, which are based on esters of citric acid, on mechanical and thermal properties of Poly(3-hydroxybutyrate)/Poly(lactic acid)/Plasticizer biodegradable blends. These plasticizers were first tested with respect to their miscibility with Poly(3-hydroxybutyrate)/Poly(lactic acid) (PHB/PLA) blends using a kneading machine. PHB/PLA/plasticizer blends in the weight ratio (wt %) of 60/25/15 were then prepared by single screw and corotating meshing twin screw extruders in the form of filament for further three-dimensional (3D) printing. Mechanical, thermal properties, and shape stability (warping effect) of 3D printed products can be improved just by the addition of appropriate plasticizer to polymeric blend. The goal was to create new types of eco-friendly PHB/PLA/plasticizers blends and to highly improve the poor mechanical properties of neat PHB/PLA blends (with majority of PHB) by adding appropriate plasticizer. Mechanical properties of plasticized blends were then determined by the tensile test of 3D printed test samples (dogbones), as well as filaments. Measured elongation at break rapidly enhanced from 21% for neat non-plasticized PHB/PLA blends (reference) to 328% for best plasticized blends in the form of filament, and from 5% (reference) to 187% for plasticized blends in the form of printed dogbones. The plasticizing effect on blends was confirmed by Modulated Differential Scanning Calorimetry. The study of morphology was performed by the Scanning Electron Microscopy. Significant problem of plasticized blends used to be also plasticizer migration, therefore the diffusion of plasticizers from the blends after 15 days of exposition to 110 °C in the drying oven was investigated as their measured weight loss. Almost all of the used plasticizers showed meaningful positive softening effects, but the diffusion of plasticizers at 110 °C exposition was quite extensive. The determination of the degree of disintegration of selected plasticized blend when exposed to a laboratory-scale composting environment was executed to roughly check the “biodegradability”.

A bioartificial rat heart tissue: Perfusion decellularization and characterization

2019 ◽  
Vol 42 (12) ◽  
pp. 757-764 ◽  
Author(s):  
Busra Ozlu ◽  
Mert Ergin ◽  
Sevcan Budak ◽  
Selcuk Tunali ◽  
Nuh Yildirim ◽  
...  
Keyword(s):  
Extracellular Matrix ◽  
Three Dimensional ◽  
Tissue Perfusion ◽  
Heart Tissue ◽  
Cell Nuclei ◽  
Tissue Sections ◽  
The Past ◽  
Significant Difference ◽  
Structural Preservation

Despite remarkable advancement in the past decades, heart-related defects are still prone to progress irreversibly and can eventually lead to heart failure. A personalized extracellular matrix–based bioartificial heart created by allografts/xenografts emerges as an alternative as it can retain the original three-dimensional architecture combined with a preserved natural heart extracellular matrix. This study aimed at developing a procedure for decellularizing heart tissue harvested from rats and evaluating decellularization efficiency in terms of residual nuclear content and structural properties. Tissue sections showed no or little visible cell nuclei in decellularized heart, whereas the native heart showed dense cellularity. In addition, there was no significant variation in the alignment of muscle fibers upon decellularization. Furthermore, no significant difference was detected between native and decellularized hearts in terms of fiber diameter. Our findings demonstrate that fiber alignment and diameter can serve as additional parameters in the characterization of biological heart scaffolds as these provide valuable input for evaluating structural preservation of decellularized heart. The bioartificial scaffold formed here can be functionalized with patient’s own material and utilized in regenerative engineering.

scholarly journals Modeling technology of curved surface development for puffer fish

2020 ◽  
Vol 12 (4) ◽  
pp. 168781402091602
Author(s):  
Honggen Zhou ◽  
Jie Cui ◽  
Guizhong Tian ◽  
Yesheng Zhu ◽  
Changfeng Jia
Keyword(s):  
Three Dimensional ◽  
Least Square ◽  
Curved Surface ◽  
B Spline ◽  
Implicit Equation ◽  
Moving Least Square ◽  
Average Value ◽  
Modeling Technology ◽  
Surface Development ◽  
Puffer Fish

The drag reduction mechanism of puffer epidermis was closely related to its real geometry. In order to solve the modeling problem of epidermal spines on the puffer surface, a modeling method for the expansion of puffer shape was proposed. The three-dimensional scanning and non-uniform rational B-spline surface modeling technology was used to reconstruct the puffer model. According to the curvature characteristics, the surface mathematical equations including exponential, logarithmic, and sinusoidal functions were established based on the multinomial function. The surface was generated by a mathematical equation, and the surface was divided into several non-uniform rational B-spline patches according to curvature. After discretization, the point cloud Gaussian curvature and average value were calculated based on the implicit equation of moving least square surface, and whether the surface is approximately extensible or not was judged. Finally, the puffer surface was divided into 46 curved patches. In this article, the surface expansion algorithm gave priority to ensure the area unchanged, and four feature surfaces were selected according to the epidermal spines arrangement of the puffer surface. The results showed that the technique can simply and efficiently unfold the curved surface of the puffer fish, thus the mapping relationship between the epidermal spines on the surface and the plane was determined, which established a foundation for the accurate arrangement and modeling of the epidermal spines on the surface.

scholarly journals A Concise Paradigm on Radical Hysterectomy: The Comprehensive Anatomy of Parametrium, Paracolpium and the Pelvic Autonomic Nerve System and Its Surgical Implication

Cancers ◽  
2020 ◽  
Vol 12 (7) ◽  
pp. 1839 ◽  
Author(s):  
Mustafa Zelal Muallem ◽  
Thomas Jöns ◽  
Nadja Seidel ◽  
Jalid Sehouli ◽  
Yasser Diab ◽  
...  
Keyword(s):  
Radical Hysterectomy ◽  
Three Dimensional ◽  
Figo Stage ◽  
Autonomic Nerve ◽  
Nerve Sparing ◽  
Anatomical Structures ◽  
Pelvic Autonomic Nerve ◽  
Direct Infiltration ◽  
Autonomic Nerve System ◽  
Nerve System

The current understanding of radical hysterectomy is more centered on the uterus and little is discussed regarding the resection of the vaginal cuff and the paracolpium as an essential part of this procedure. The anatomic dissections of two fresh and 17 formalin-fixed female pelvis cadavers were utilized to understand and decipher the anatomy of the pelvic autonomic nerve system (PANS) and its connections to the surrounding anatomical structures, especially the paracolpium. The study mandates the recognition of the three-dimensional (3D) anatomic template of the parametrium and paracolpium and provides herewith an enhanced scope during a nerve-sparing radical hysterectomy procedure by precise description of the paracolpium and its close anatomical relationships to the components of the PANS. This enables the medical fraternity to distinguish between direct infiltration of the paracolpium, where the nerve sparing technique is no longer possible, and the affected lymph node in the paracolpium, where nerve sparing is still an option. This study gives rise to a tailored surgical option that allows for abandoning the resection of the paracolpium by FIGO stage IB1, where less than 2 cm vaginal vault resection is demanded.

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