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Braille is a universal tactile writing system for the blind and visually impaired. Braille can be printed in several ways, including embossing, screen, or UV ink-jet printing. In this study, we propose to use three-dimensional, 3D, printing technology to print dots of the Braille alphabet. The 3D model was designed with CAD software and then overprinted with Fused Deposition Modelling, FDM, technology with polylactide filament. Then, the quality of braille dots was assessed according to the standard for Braille. The estimated height (0.5 mm) and diameter (1.3 mm) for Braille dot were not achieved for the designed model. The measured values of the Braille dots were 0.38 ± 0.03 mm and 1.0 ± 0.07 mm for the height and diameter, respectively. The dot quality was assessed with an optical microscope. The distribution and location of the Braille can be acceptable, but the reproduction of dot shape, curvature, and dimensions is not compatible with the standard for Braille dots. Despite that, Braille is readable, and FDM can be a cheap solution to develop customized and unique plates with Braille imitating conventional Braille dots embossed in cardboard. [ABSTRACT FROM AUTHOR]

Additive manufacturing methods give the opportunity to produce interesting, new structures with a more complicated topology than would be possible using traditional methods. Using the selective laser sintering method, a disk with a high roughness and porous structure was produced. Studies of material surface were performed on microscopic devices. An in vitro experiment was performed on the manufactured disk using mice fibroblastic cells. The designed shape enabled the growth of the cell culture in the disc pores and ensured impermeability of the disc base. On the basis of the average viability of 79%, which is close to reference well (80%), preliminary results confirmed that the manufactured structures create sufficiently comfortable conditions for the cell cultures without the need to design their internal topography. Controlling the production parameters of SLS printing allows obtaining the structures characterized by spatial and surface porosity without designing inner geometry of the structure. Polyamide 2200 (PA2200) powder with a laser beam, offers new possibilities for producing surfaces used in the tissue engineering, bioreactors, and microfluidics devices. [ABSTRACT FROM AUTHOR]

A novel Timoshenko beam model enriched to account for dissipation in cement-based materials was presented in this paper. The model introduced a new variable representing the relative sliding inside microcracks within the material. In the paper, the microcrack density was not supposed to increase, assuming a small deformation regime that implied no damage growth. The model utilized an expanded version of the principle of virtual work whose contributions came from external forces, internal elastic forces, and dissipation due to the microcrack's microstructure. The elastic energy included terms related to microcrack sliding and micro-macro interactions, accounting for nonlinearity in the material behavior. Numerical simulations, conducted using the finite element method, evaluated the mechanical properties of cement-based materials under three-point flexural tests and compression tests. These tests enabled the assessment of the material dissipative behavior under cyclic loading. Results showed dissipated energy cycles and mechanical responses influenced by the microcrack mechanics. Additionally, a parametric study, varying the friction force amplitude, revealed its impact on dissipated energy. The study highlighted a non-monotonic relationship between friction force amplitude and dissipated energy, with an optimal value maximizing dissipation. Overall, the model provided insights into the mechanics of cement-based materials, particularly regarding dissipation, which was essential for understanding their behavior in structural applications. [ABSTRACT FROM AUTHOR]

In this paper, we present a novel theoretical model of bone evolution. The model takes into account growth of the blood vessels network as a real issue during the process. The stimulation of this growth is controlled by the signals from overloaded dying cells. A system of integro-differential equations describes changes in the density of blood vessels, bone cells and Young modulus, all of which define how the bone tissue evolves over time. The model considers several biomechanical signals such as changes in the density of elastic strain energy and nutrients. Two examples of changing bone tissue were examined to test the model: bone healing around a tooth implant and formation of osteophytes during osteoarthritis. In both cases, the effects of mechanical loading in the bone tissue evolution which are in agreement with the medical observations can be observed. [ABSTRACT FROM AUTHOR]

Osteoarthritis, one of the most common types of arthritis, is characterized by the development of osteo- phytes. The main cause of joint degeneration is mechanical loading, but there are also several other factors that influence the development of osteophytes. In order to formulate a mathematical model of bone spurs' development we have selected the most important factors, such as angiogenesis, micro-damage of the tissue structure and cell signaling. The proposed system of integro-differential equations describes the degen- erative changes in the joint. Numerical calculations were implemented into the COMSOL Multiphysics software and the obtained results thus reflect relationships between certain parameters and variables. Additionally, the results correspond with those obtained from medical observations. [ABSTRACT FROM AUTHOR]

The article offers information on the International Project Management Association (IPMA) Project Excellence Award 2014, which recognizes projects from different organizations and industries. It says that the award is aimed at increasing the recognition of best-managed projects and at motivating project teams for project management development. It mentions the benefits offered by the IPMA Project Excellence including assessment process, prestige, and winners club.

The article announces the 2013 International Project Management Association (IPMA) Excellence Awards given to projects including South Australian Water Corp. for a desalination project, PetroChina Guangxi Petrochemical Co. for a refinery project, and Tecnimont SpA for a biomass powerplant project.

The article offers the author's insights on the International Project Management Association (IPMA) Project Excellence (PE) Award Assessors Training that was held in Warsaw, Poland from February 21-23, 2014. Topics include the statement of Hossein Ossooli of Iran about the training's advanced level, the role of professional assessment applied for the PE Award, and the suggestion from Ayman Nabet of Jordan on setting new standard for Training planners.

The article focuses on the International Project Excellence Award 2014 of the International Project Management Association (IPMA) particularly on the role of project assessors in the awards. It mentions that the award is given with the aid of the project assessors where every year around 100 of them are recruited to evaluate the best-managed projects in the world. It also mention the assessors for the 2014 award and their qualifications.