Improved image processing for 3D virtual object construction from serial sections reveals tissue patterns in root tips of Zea mays.

Premise: Previously we described methods for generating three-dimensional (3D) virtual reconstructions of plant tissues from transverse thin sections. Here, we report the applicability of longitudinal sections and improved image-processing steps that are simpler to perform and utilize free applications. Methods: In order to obtain improved digital images and a virtual 3D object (cuboid), GIMP 2.10 and ImageJ 2.3.0 running on a laptop computer were used. Sectional views of the cuboid and 3D visualization were realized with use of the plug-ins "Volume Viewer" and "3D Viewer" in ImageJ. Results: A 3D object was constructed and sectional views along several cutting planes were generated. The 3D object consisted of selected tissues inside the cuboid that were extracted and visualized from the original section data, and an animated video of the 3D construct was also produced. Discussion: Virtual cuboids can be constructed by stacking longitudinal images along the transverse depth direction or stacking transverse images vertically along the organ axis, with both generating similar 3D objects. Which to use depends on the purpose of the investigation: if the vertical cell structures need close examination, the former method may be better, but for more general spatial evaluations or for evaluation of organs over longer tissue distances than can be accommodated with longitudinal sectioning, the latter method should be chosen.

Patient-derived organoids in translational oncology and drug screening.

Patient-derived organoids (PDO) are a new biomedical research model that can reconstruct phenotypic and genetic characteristics of the original tissue and are useful for research on pathogenesis and drug screening. To introduce the progression in this field, we review the key factors of constructing organoids derived from epithelial tissues and cancers, covering culture medium and matrix, morphological characteristics, genetic profiles, high-throughput drug screening, and application potential. We also discuss the co-culture system of cancer organoids with tumor microenvironment (TME) associated cells. The co-culture system is widely used in evaluating crosstalk of cancer cells with TME components, such as fibroblasts, endothelial cells, immune cells, and microorganisms. The article provides a prospective for standardized cultivation mode, automatic morphological evaluation, and drug sensitivity screening using high-throughput methods.

Effectiveness of Polymer Additives in Concrete for 3D Concrete Printing Using Fly Ash.

The article shows the effectiveness of the use of polymer additives for the production of fine-grained concrete mixtures and concretes based on using coal fly ash, which can be used as working mixtures for a 3D printer. Using mathematical planning of experiments, a set of experimental-statistical models was obtained that describes the influence of mixture composition factors including copolymer additive on the most important properties of ash-containing concrete mixtures and concretes for 3D concrete printing in the presence of a hardening accelerator additive. It is shown that when the dry mixture is mixed in water, the redispersed polymer powders are converted into an adhesive polymer dispersion, which, when the solution cures, creates "rubber bridges" in its pores and at the border with the base. They have high tensile strength and elastically reinforce the cement stone; in addition, they are also capable of not only significantly increasing the adhesion between the layers of the extruded mixture, but also significantly smoothing out such shortcomings of the cement stone as increased brittleness, low ultimate elongation, and a tendency to cracking.

Digital Determination and Recording of Edentulous Maxillomandibular Relationship Using a Jaw Movement Tracking System.

PURPOSE: To establish a direct digital method for determining and recording edentulous maxillomandibular relationship using a custom-made jaw movement tracking system and evaluate its accuracy. MATERIALS AND METHODS: A novel jaw tracking system was used to record the trajectory of habitual opening-closing jaw movement, and mandibular rest position (MRP) in 10 edentulous patients. 3D surface scanning was performed on the conventional maxillomandibular impressions and facial structures of patients in MRP. The multisource data were registered using a custom-made recording tool. A plane parallel to the ala-tragus and horizontal lines was constructed 2 mm above the MRP, and its vertical position was used to determine the vertical relationship. The intersections of the trajectory passing through the plane were located, and their density distributions were analyzed. The coordinates of highest density, which presented the highest repeatability of jaw movement, were used to construct the digital maxillomandibular relationship (test group). The maxillomandibular relationship of the new complete dentures with artificial teeth in the intercuspal position was defined as the control group. The displacements of the anterior reference point and 3D deviations of the entire mandibular arch were measured and compared between the test and control groups using a Wilcoxon signed-ranks test and a one-sample t-test, respectively. RESULTS: With reference to the centric relationship position, the maximum displacements of the anterior reference points were in the horizontal anteroposterior direction for both groups, and there were no significant differences. Compared to the control group, the 3D deviations of the entire mandibular arch in the test group were significant (95% confidence interval: 0.76 mm to 1.35 mm, p < 0.001). CONCLUSIONS: By analyzing the individual trajectory features obtained by the in-house developed jaw tracking system, a digital method for determining and recording edentulous maxillomandibular relationships was established; however, the accuracy needs to be further improved.

A Novel Method for the Complex Tube System Reconstruction and Measurement.

Pipe structures are at the base of the entire industry. In the industry structure, heat and vibration are transmitted in each pipe. The minimum distance between each pipe is significant to the security. The assembly error and the deformation of the pipeline positions after multiple runs are significant problems. The reconstruction of the multi-pipe system is a critical technical difficulty in the complex tube system. In this paper, a new method for the multi-pipes structure inspection is presented. Images of the tube system are acquired from several positions. The photogrammetry technology calculates positions, and the necessary coordination of the structure is reconstructed. A convolution neural network is utilized to detect edges of tube-features. The new algorithm for tube identification and reconstruction is presented to extract the tube feature in the image and reconstruct the 3D parameters of all tubes in a multi-pipes structure. The accuracy of the algorithm is verified by simulation experiments. An actual engine of the aircraft is measured to verify the proposed method.

A Feasibility Study on HPMC-Improved Sulphoaluminate Cement for 3D Printing.

A novel 3D printing material based on hydroxypropyl methylcellulose (HPMC)-improved sulphoaluminate cement (SAC) for rapid 3D construction printing application is reported. The hydration heat, setting time, fluidity of paste and mortar, shape retainability, and compressive strength of extruded SAC mortar were investigated. HPMC dosage, water-to-cement (W/C) ratio, and sand-to-cement (S/C) ratio were studied as the experimental parameters. Hydration heat results reveal HPMC could delay the hydration of SAC. The initial and final setting time measured using Vicat needle would be shortened in the case of W/C ratio of 0.3 and 0.35 with HPMC dosage from 0.5% to 1.5%, W/C ratio of 0.40 with HPMC dosage of 0.5%, 0.75%, and 1.5%, and W/C ratio of 0.45 with HPMC dosage of 0.45, or be extended in the case of W/C ratio of 0.4 with HPMC dosage of 1.0% and W/C ratio of 0.45 with HPMC dosage from 0.75% to 1.5%. Fluidity measurement shows HPMC significantly improves the shape retainability. Furthermore, the addition of HPMC remarkably increased the compressive strength of extruded mortar. The results showed that HPMC could be used to prepare 3D printing SAC having satisfactory shape retainability, setting time and compressive strength.

Construction of 3D Metallic Nanostructures on an Arbitrarily Shaped Substrate.

Constructing conductive/magnetic nanowire arrays with 3D features by electrodeposition remains challenging. An unprecedented fabrication approach that allows to construct metallic (cobalt) nanowires on an arbitrarily shaped surface is reported. The spatial separation of nanowires varies from 70 to 3000 nm and the line width changes from 50 to 250 nm depending on growth conditions.