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Using nanotechnology to produce composite materials it has been possible to obtain materials with similar or better mechanical properties than previous generation of microhybrids, and with exceptional aesthetics and chandelier due to the particularities of nanomaterials. At the same time, the improvement of adhesive techniques to enamel and dentin allowed the expansion of the area of direct composite restorations with a better prognostic over time.Eight carie-free molars were used and each of them was prepared with two class II cavities, which were filled using the C13 and C20 nanocomposites and the A1 and A2 experimental adhesive systems prepared at the Raluca Ripan Chemistry Research Institute. The teeth were divided into four groups of two teeth each, depending on the adhesive system and the composite material used. Scanning electron microscopy images (SEM) have described the adhesive interface and structure characteristics for the two nanocomposite materials and for the two studied adhesive systems.The studied nanocomposites have a variable number of porosities and air bubbles, with a clinical importance which is yet hard to establish.The experimental adhesives used produce a good interface and infiltration of the smear-layer but have not been visualized inside the dentinal canals.In vitro studies are necessary to evaluate the durability of adhesion in the case of self-etch adhesives in one or two steps.

The species from the increased biofouling on the paint layers applied to the metallic strength structure of a railway bridge located in a Natura 2000 protected area have been identified by specific biologic and microbiological methods. As a result of the analysis of the biological samples taken on the field, it has been found that relatively large variety of filamentous molds are present (Aspergillus fumigatus, Asprgillus flavus, Aspergillus niger, Paecilomyces variotii, Chaetomium globosum, Trichoderma viride, Stachybotris atra, Trichoderma sp., Alternaria sp and Penicillium sp.). Samples also show, lichens (Xanthoria parietina and Hypogymnia physodes) and lower plants capable of photosynthesis such as algae (Chlorophyta Xanthophyceae, Chrysophyceae) and moss (Lunularia cruciata, Marchantiophyta).

This paper presents a study undertaken following the collaboration between specialists in two multidisciplinary fields, namely engineering and medicine. It was aimed at solving a practical problem by developing of a handle for use in orthopedic surgery. Specific engineering tools, knowledge and processes and methods were used for accomplishing this task. Tailoring devices according to surgeons preferences for ensuring an ergonomic use is an important criterion alongside functional and sterilization requirements, cost and fabrication time, 3D printing representing a feasible manufacturing solution as this research proves. The article details the steps required to complete the final product: design and redesign, numerical analysis, prototypes manufacturing and testing. To perform the numerical analysis that highlights the device mechanical behavior, finite element method was used in assessing different handle designs.

The aim of the present paper was to characterize the new pink PMMA doped with 0.4% TiO2 nanoparticles utilized for denture base manufacturing as alternative to the one-piece, single color material for removable denture. The PMMA base material was structurally characterized through XRD, SEM, EDX, and subsequently by FT-IR and Raman spectroscopy. An improvement in the thermal stability of the obtained material compared with the PMMA matrix without filler was evidenced. All performed structural analyzes are recommending the new pink PMMA with 0.4% nano-titania as an as an alternative to the one-piece, single color material for removable dentures processing.

The paper presents the results of investigations on the transmission of electromagnetic radiation from the UV-Vis ranges of organic colored spectacle lenses. All investigated lenses had the same refractive index and one of them differed in the SPF (sun protection factor). The main criterion for the quality of colored eyeglass lenses is eye protection against harmful UV radiation, infrared radiation and excessive exposure to solar radiation. The lenses were measured using a Varian UV-Vis Cary model 300 spectrophotometer. These studies showed that the best protection against this radiation is the choice of coloring in a color other than blue, and that as the power of the colored lens increases, protection against harmful UV radiation decreases.

The aim of this study was the development and formulating of a cosmetic product for bodycare and the assessment of compatibility tests performed on the product, transfered into a poliethylene (PE) cosmetic bottle. Sample of cosmetic cream were stored using 200 ml PE plastic bottles with PP (Polypropylene) cap. The developed cosmetic formulation was monitored under accelerated stability studies, performed over a period of 30 days while maintaining the product at 4, 20 and 40°C. Quality control initial, and after initiating the accelerated stability test was performed for the developed cosmetic formulation.

One of the most common postoperative complications that may occur in patients treated for incisional hernias is pain. The occurrence of postoperative pain refractory to drug treatment may worsen the prognosis of these patients. We have carried out a retrospective observational study in which we have introduced 122 patients operated for incisional hernia at the Surgical Clinic No. 1 in the Tirgu Mures Emergency County Clinical Hospital. The patients included in the study were divided into two groups: group A consisting of 80 patients where the polypropylene mesh was used over the aponeurosis in the surgical treatment of the incisional hernias, and the group B consisting of 42 patients where no prosthetic materials were used in the surgical treatment of the incisional hernias. All patients were administrated 1 g of sodium metamizole monohydrate for the treatment of pain. The statistical analysis of the data revealed that, on the day of surgery, on the first, second and third postoperative day there were statistically significant differences in the need for analgesic medication between the two groups, the need for the analgesic medication being lower for group A. In contrast, on the 4th postoperative day there were no statistically significant differences in the need for analgesic medication between the two groups. In conclusion, our study showed that, when using the polypropylene mesh in the surgical treatment of incisional hernias, the need for analgesic medication is lower in the immediate postoperative period compared to cases where surgical meshes are not used in the surgical treatment of these patients.

This article presents the design of a specific unmanned aerial vehicle UAV prototype own building. Our UAV is a flying wing type and is able to take off with a little boost. This system happily combines some major advantages taken from planes namely the ability to fly horizontal, at a constant altitude and of course, the great advantage of a long flight-time. The aerodynamic models presented in this paper are optimized to improve the operational performance of this aerial vehicle, especially in terms of stability and the possibility of a long gliding flight-time. Both aspects are very important for the increasing of the goals’ efficiency and for the getting work jobs. The presented simulations were obtained using ANSYS 13 installed on our university’ cluster system. In a next step the numerical results will be compared with those during experimental flights. This paper presents the main results obtained from numerical simulations and the obtained magnitudes of the main flight coefficients.

This work has described the production of single-polymer composites by the film-stacking method. Two types of single-polymer composites with different mass fractions of the polyester reinforcement phase (10% and 20%) and the PETG matrix were investigated. The produced composites were subsequently recycled by injection moulding, pressing, and extrusion. Selected properties of the processed composites were determined: density, viscosity-average molecular weight, impact resistance, and tensile strength. The work done in this paper has demonstrated the benefits and drawbacks of each recycling method for these materials. The selected properties of single-polymer polyester composites and single-polymer polyester composites that were recycled by extrusion have also been compared.

The purpose of this study was to determinate , using the Finite Element Analysis Method, the mechanical stress in a solid body , temporary molar restored with the self-curing GC material. The originality of our study consisted in using an accurate structural model and applying a concentrated force and a uniformly distributed pressure. Molar structure was meshed in a Solid Type 45 and the output data were obtained using the ANSYS software. The practical predictions can be made about the behavior of different restorations materials.