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In the medical field of plastics is and will be most useful. Their processing involves engineering concepts which assumes the most diverse risks. But there are conditions, depending on the identification between offer and demand of such services. They come as effects of the concrete availability of resources of all types, of caring facilities, comparing with the demand based on the need for health. In this context the analysis due to risk engineering is appropriate in the management accomplishments of the processors, respectively as it can be used at national and international levels, having effects on the efficiency of the usage of al the involved resources. Keywords: industrial system, risk engineering, plastic materials

The placenta handles the exchange of oxygen and nutrients from the mother to the fetus. Normal placentation and placental development are critical for a successful pregnancy. In this study, the placenta is obtained from normal pregnancy and of normal vaginal delivery. The polymeric cast of the fetal vasculature of the full-term placenta is used to perform a numerical simulation of the blood perfusion in the placenta. Vascular corrosion casting is an established method of anatomical preparation that has proven to be an an excellent tool for detailed three-dimensional (3D) morphological examination of normal and pathological microcirculation. Performed numerical simulation indicated that the velocity profiles in the placental vessels are close to parabolic profiles. Keywords: placenta, corrosion cast, numerical simulation, fetoplacental vasculature

In the European Union, the concept of sustainable development covers all the environmental fields, from development politics to the appropriate management of waste, in respect to the future generations. Therefore, the aim of this study is to prove that electronic waste scraps can be used to manufacture a new modern and ecological composite material, which can be used in construction field. The Electric and Electronic Equipment (EEE) amounts, on the market, are increasing from one year to another. At the end of life, only half of the generated waste, named e-waste or Waste of Electric and Electronic Equipment (WEEE), is collected. Knowing that the e-waste is framed as hazardous waste, because of its hazardous substances content, the challenge of our society is safe recycling, to confer security to human health and environment. The obtained composite is a new material which contains cathode ray tubes (CRT) glass waste and plastic scraps from WEEE. The composite experimental strength results (39.24 N/mm2), entitled its classification into the mortars category. The WEEE recycling method used to obtain this type of composite is an environmentally friendly one. Keywords: cathode ray tubes (CRT), composite, plastic, waste recovery

This paper deals with the analysis of temperature effect over the viscosity of the polymeric mixtures used in plastination studies. Two reaction mixtures were prepared respecting the standard protocol of the Biodur S10/15 technique. For these two mixtures, viscosity measurements were performed at -25 °C, +20 °C and +40 °C, after one day, one week, two weeks, three weeks and four weeks, respectively after preparation. These parameters were chosen rationally, since the standard impregnation time for the cold silicone method is three weeks. These results were also corroborated to the acetones’ vapor pressure, showing that for Biodur silicone, impregnation at room temperature is possible. A maximum of two weeks of impregnation was determined for S10, while for S15, this could be realized over a period of three weeks. Keywords: silicone viscosity, impregnation, S10/S15 technique, room temperature, cold method plastination

In this paper, were determined the mechanical properties for Dammar based composite materials. For the begining, were determined the mechanical properties (elasticity modulus, breaking strength, breaking elongation, transversal Poisson ratio) for samples made from a resin whose Dammar is its main part. Based on this resin, were made composite materials, using as reinforcement fabrics from cotton, silk, flax and hemp. For each composite type were experimentally determined the same mechanical properties as in the case of resin based samples. Keywords: textile composites, mechanical properties, stress/strain curves, elastic properties, fractography

On a total of 150 renal corrosion casts with a single renal artery, the artery of superior segment was examined. Three morphological types have been highlighted: Type I, in which the superior segmental artery originating directly in the trunk of the renal artery (8.67% of cases); Type II, in which the superior segmental artery arises from the anterior branch of the renal artery (81.33% of cases); Type III, in which the superior segmental artery arises from the posterior branch of the renal artery (10% of cases). In 78% of cases, the superior segmental artery arises independently from the trunk or renal artery branches (anterior or posterior). In 22% of cases, the superior segmental artery realizes a common trunk with one or more other segmental arteries. Knowledge of these aspects is important both to investigate morphological imaging and performing partial resection of the renal parenchyma. Keywords: kidney; corrosion casts; superior segmental artery; variations

Dental composites, some of the most used materials in the last decade, have been and still are the focus of the researches in the last period of time. The present study aims to evaluate three of the most used composites given their different behaviour in practice. There were performed: the flexural strength test, the compression strength and resistance test at diametral compression according to ADA Sp.27/1993 specification. The results were surprising given the differences between the values obtained for the samples of each material. The study concludes that the variable properties of the composites in the same conditions originate from their inconstant microscopic structure. Keywords:dental composites, flexural strength test, compression strength, esistance test

Membrane processes are a way to remove unwanted elements from wastewater stream. The permeability is an important parameter to filter wastewater and membrane fouling is of great interest in membrane filtration because reduce wastewater flow through the membrane. In order to improve the filtration process, many studies have investigated the use of nanoparticles added in the polymeric membranes and how much influence the permeation properties of membranes. A variety of nanoparticles have been used to modify polymer membranes, such as Al2O3, SiO2, TiO2, ZrO2, Fe3O4, Ag. Nanoparticles are used to improve the properties of membranes like hydrophilicity, permeability and fouling resistance. This paper shows the influence of the TiO2 nanoparticles with a concentration of 0.125 wt.%, on the permeation properties and dyes rejection of the PES and PSf membranes and makes a comparison with the results obtained by other authors. Keywords: TiO2 nanoparticles, PES, PSf, membranes

Respiratory movements monitoring is critical in ensuring optimal patient supervision, especially in critical cases and also in diagnosing sleep apnea syndrome.The aim of our paper is to assess the possible role of magnetic impedance (MI) effect in respiratory movements recording.The study was carried out on 6 volunteers using a special mat equipped with quasi-non-contact MI sensors. Evaluation consisted in monitoring and recording the amplitude and frequency of the respiratory movements during normal breathing and while performing Valsalva maneuver.The constancy of pattern and amplitude of waves recorded suggests that this kind of respiratory movement monitoring may have considerable clinical application in monitoring critical patients and also sleep disorders, especially for children suspected of sleep apnea. Keywords: Amorphous Ferromagnetic Materials, Magneto impedance, Sensor, Breathing, Apnea

The aim of this study was to point out the effect of porous clay heterostructure (PCH) and polymer concentration on thermal and dynamic mechanical properties of Sodium Alginate (SA) based hybrid films. New hybrid films based on SA and PCH were prepared by solvent casting method using different polymer concentrations and clay loadings. The interactions between nanofiller (PCH) and polymer matrix (SA), thermal stability and dynamic mechanical properties of neat SA and hybrid films were evaluated by Fourier transform infrared (FTIR) spectroscopy, thermogravimetric analysis (TGA) and dynamic mechanical analysis (DMA). The obtained results showed the influence of PCH within SA on the storage modulus and a moderate change of thermal stability, the glass transition temperature being also recorded. The concentration of SA solution and PCH are significant factors which affect the thermal and mechanical properties of hybrid films. Keywords: sodium alginate, porous clay heterostructures, hybrid films, thermal stability, dynamic mechanical analysis