Imaging of increasingly complex cartilage in vertebrate embryos is one of the key tasks of developmental biology. This is especially important to study shape-organizing processes during initial skeletal formation and growth. Advanced imaging techniques that are reflecting biological needs give a powerful impulse to push the boundaries of biological visualization. Recently, techniques for contrasting tissues and organs have improved considerably, extending traditional 2D imaging approaches to 3D. X-ray micro computed tomography (µCT), which allows 3D imaging of biological objects including their internal structures with a resolution in the micrometer range, in combination with contrasting techniques seems to be the most suitable approach for non-destructive imaging of embryonic developing cartilage. Despite there are many software-based ways for visualization of 3D data sets, having a real solid model of the studied object might give novel opportunities to fully understand the shape-organizing processes in the developing body. In this feasibility study we demonstrated the full procedure of creating a real 3D object of mouse embryo nasal capsule, i.e. the staining, the µCT scanning combined by the advanced data processing and the 3D printing. K : Computerized Tomography (CT) and Computed Radiography (CR); Image reconstruction in medical imaging; Multi-modality systems 1Corresponding author. Content from this work may be used under the terms of the Creative Commons Attribution 3.0 License.

Purpose This paper aims to focus on the evaluation of a polymer concrete as a three-dimensional (3D) printing material. An associated company has developed plastic concrete made from reused unrecyclable plastic waste. Its intended use is as a construction material. Design/methodology/approach The concrete mix, called PolyBet, composed of polypropylene and glass sand, is printed by the fused deposition modelling process. The process of material and parameter selection is described. The mechanical properties of the filled material were compared to its cast state. Samples were made from castings and two different orientations of 3D-printed parts. Three-point flex tests were carried out, and the area of the break was examined. Computed tomography of the samples was carried out. Findings The influence of the 3D printing process on the material was evaluated. The mechanical performance of the longitudinal samples was close to the cast state. There was a difference in the failure mode between the states, with cast parts exhibiting a tougher behaviour, with fractures propagating in a stair-like manner. The 3D-printed samples exhibited high degrees of porosity. Originality/value The results suggest that the novel material is a good fit for 3D printing, with little to no degradation caused by the process. Layer adhesion was shown to be excellent, with negligible effect on the finished part for the longitudinal orientation. That means, if large-scale testing of buildability is successful, the material is a good fit for additive manufacturing of building components and other large-scale structures.

Purpose This paper aims to study the appearance of drills from one brand by using currently available design tools. It aims to find and discuss the relationship between appearance innovation and maintaining key design features. Design/methodology/approach The innovation process is studied on drills of a Czech power tool maker and a previously created concept of a new drill. First, the authors explore the similarities between the designed concept and previous models of the brand by calculating the degree of similarity of given shape features. Second, they capture the drills simple shape grammar and strive to generate a sketch of the concept. Findings Results show the use of several similar shape features from previous models in the innovated design. Shape grammar can create a principally similar concept, but some innovations cannot be achieved this way. A description of appearance innovation within brand identity in terms of shape grammar is given. Research limitations/implications The research is limited mainly to a small group of previous products that can be analyzed. It is done only for one particular brand identity. When used with the shape grammars, design generation is limited. Practical implications Better understanding of the innovative process aids designers in working with designs for brand identity and may serve to shape grammar enhancement. Originality/value The paper describes what happens during the innovation of product appearance and implicates enhancement and meaning of design analysis done by shape grammars and exploring similarities.

We present the design of the first prototype of TOK -a tangible interface for children to create their own stories. Based on data collected with two groups of five years old preschoolers we present our findings regarding the interaction design of the system. The picture cards have shown to generate ideas, acting as input for the creation of stories, promoting creativity while proposing a framework that supports and guides the construction of logical structures. This is a first step in an effort to build a toolkit of tangible interfaces allowing children and teachers to build their own digital enhanced learning activities.

3D concrete printing technology (3DCP) is a relatively new technology that was first established in the 1990s. The main weakness of the technology is the interface strength between the extruded layers, which are deposited at different time intervals. Consequently, the interface strength is assumed to vary in relation to the time of concrete casting. The proposed experimental study investigated the behavior of a hardened concrete mixture containing coarse aggregates that were up to 8 mm in size, which is rather unusual for 3DCP technology. The resulting direct tensile strength at the layer interface was investigated for various time intervals of deposition from the initial mixing of concrete components. To better understand the material behavior at the layer interface area, computed tomography (CT) scanning was conducted, where the volumetric and area analysis enabled validation of the pore size and count distribution in accordance with the layer deposition process. The analyzed CT data related the macroscopic anisotropy and the resulting crack pattern to the temporal and spatial variability that is inherent to the additive manufacturing process at construction scales while providing additional insights into the porosity formation during the extrusion of the cementitious composite. The observed results contribute to previous investigations in this field by demonstrating the causal relationships, namely, how the interface strength development is determined by time, deposition process, and pore size distribution. Moreover, in regard to the printability of the proposed coarse aggregate mixture, the specific time interval is presented and its interplay with interface roughness and porosity is discussed.

The article describes modifications to the effector of a manipulator arm proposed in order to increase the accuracy of jaw force measurements. Gripping force measurement is performed using strain gauges. Their proper positioning and connection minimize not only the influence of the position of the centre of gravity of the manipulation object on the jaws but also the effect of temperature changes around the measuring area. The possibility of altering the magnitude of gripping force was incorporated into the robot control application. This greatly increases the security of handling and increases the number of items that can be possibly gripped. Modified effector parts were subjected to stress analysis, with emphasis on the elimination of stress peaks that would not occur in real parts. The article also describes the design of the mechanical modification of the effector, which would allow the continuous rotation of the jaws of the effector.

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