The aim of this research was to evaluate mutual interchangeability of four principally different biometric instrumental techniques designed for objective measurement of changes in the physical, mechanical, and topographical properties of the skin surface treated with commercial antiaging cosmetic products with hyaluronic acid. The following instrumental devices were used: Visioscope PC 35, Corneometer Multiprobe Adapter MPA 6, Reviscometer RVM 600, and 3D scanner Talysurf CLI 500. The comparison of the individual methods was performed using cluster analysis. The study involved 25 female volunteers aged 40-65. Measurements were taken before and after 30 daily in vivo applications of an antiaging preparation to the skin surface in the periorbital area. A slight reduction in skin surface roughness was recorded in 55% of the volunteers. On the contrary, a worsening from their initial states was detected in 25% of the subjects, while for 20%, no significant change was reported. Cluster analysis confirmed that the mentioned methodologies can be divided into two basic clusters, namely, a cluster of methods recording the changes in skin relief by means of optical techniques, and a cluster of methods investigating changes in hydration and anisotropy. In practice, the techniques in different clusters are not interchangeable and should be assessed separately.

This study is focused on the development of a methodology for objective measurement of changes in treated skin relief using 3D scanning. The results are evaluated using fractal dimension. The output may also include also an enlarged model of the skin surface made by 3D printer, which can serve for illustrative communication with the client.

This work is focused on the influence of heat treatment of a part produced by the SLM (selective laser melting) method of stainless steel, 316L. Two heat treatment regimens were tested and compared with the state without heat treatment. Subsequently, TIG (tungsten inert gas) welds were created on the base materials processed in this way. All welds were subjected to mechanical tests and microstructural analysis. The tensile test was performed both for the welded joint and for the base material in the transverse and longitudinal directions. The tensile strength values of the samples with the welded joint were compared with the values required for the base material, 316L forged steel (1.4404). Microstructural analysis revealed significant differences between samples with and without heat treatment. The results of these tests are supported by SEM analysis. EDAX (energy dispersive analysis of X-rays) semiquantitative analysis confirmed the presence of ultra-fine pores in the structure. The results of mechanical tests show that the solution annealing at 1040 °C for 0.5 h gives better results than the same heat treatment with a duration of 2 h.

One of the most important characteristics of a cosmetic product is maintain or improving the condition and characteristics of the skin surface. In dermatological, respectively cosmetic practice, there is very often a problem of an objective assessment of the obtained data, which corresponds to visual changes in skin relief. With technical advancements has it been proposed many approaches of solution: mechanical needle devices, optical interference devices, and microscopic, holographic, laser and photometers ones. Each of them has its advantages and negative qualities. The newest devices allow not only two-dimensional assessment (2D), but also spatial one (3D). Scientific literature such as Measuring the Skin recommends for these cases scanning the surface in 3D, using the contact scanners for made imprints. Here, however, errors that may be caused by mechanical method of scanning skin relief are not taken into consideration and there is also not clearly described the material suitable for the production of custom impression. The following article focuses precisely on this issue, specifically on the implementation of the biological surface relief imprint using a silicone impression material, its 3D scanning without contact and forming an enlarged replica by rapid prototyping technology.