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Stem cells are nowadays isolated from multiple sources and used in biotechnological application. Our study presents a new method for isolation and expansion of stem cells derived from infrapatellar fat pad (IPFP) by simple adherence to plastic surface of culture flasks. This method yielded adipose-derived stromal cells (ASC) with morphological and phenotypical characteristics of mesenchymal stem cells, without using any enzymatic digestion, making these cells more suitable for medical application, in treatment of different human pathologies.

In order to find alternative solutions for protection of hydraulic turbine components against cavitation, a fluid elastomer layer, curing at room temperature, was deposited onto a martensitic stainless steel substrate. The resistance of the coating to cavitation erosion was determined by the vibratory indirect method, using ultrasonic equipment with piezoelectric converter and the microstructure of the polymer was investigated using scanning electron microscopy (SEM) and energy dispersive X-ray analysis (EDX). The authors compared the cavitation erosion resistance of the elastomer layer with that of the base material (martensitic stainless steel) as well as that of protective cold hardening austenitic stainless steel coatings, deposited by overlay welding onto the base material. The experimental results revealed that the elastomer coating ensures better resistance to cavitation erosion than both stainless steel types.

Biomaterials for bone regeneration techniques can preface rehabilitation implantation, may intervene in the same step with the implantation, or they can find the insertion in reconstructive periodontal therapy. This study aimed to quantify the contribution that different materials may bring for bone regeneration potential in gum regeneration in resizing bone structures affected, in order to establish oral rehabilitation.There were considered a total of five bone regeneration materials(Hidroxiapatite, Bio-Oss, OsteoGraf /N, Osteogen, Cerasorb ), applied in similar clinical situations, radiological assessment of bone regeneration issues, made before the application, immediately after application and 6 months after application. Regarding the quality of bone neo formation, the bone structure was very dense when using Bio-oss and Cerasorb, relevant issues the X-ray that provides the necessary information. In terms of clinical results, they were very good for the other three biomaterials used for bone regeneration. When used properly, biomaterials for bone regeneration provide very good results in terms of maintaining bone volume to withstand the demands, offering also a high percentage of vitality, safety and lack of complications.

Since its discovery, more than eight decades ago, the epoxy resin grew quickly to be largely used in all-day activities around the world. This paper presents the evolution of utilization of the epoxy resin around the world, since its discovery until our times. Also, being such a familiar material in all industries, an analyses of its impact on the economy is also addressed in the second part of this study, revealing its importance on the economy of the countries on the both sides of the Atlantic Ocean. The research involving the utilization of the epoxy resin is still underway at this time, an interesting path being taken in Romania at the Research and Development Center for Thermoset Matrix Composites that is part of the “Dunãrea de Jos” University of Galati. Some of the ideas, already partially put in practice are presented in the last part of this article, the utilization of this resin as part of a composite being the main focus of obtaining some materials needed in green-energy production.

This study presents a novel strategy for the modulation of the stop band of a polymer photonic crystal by utilizing the pattern on the surface of a written DVD. Thus, fluorescent dye doped polymer colloids (305 nm) capable to self-assemble have been obtained through soap-free emulsion polymerization and deposited on the surface of the DVD, both the top and bottom. The resulting films were investigated by SEM, UV-Vis and fluorescence spectroscopy. Depending on the design of the surface, the modification of the band gap, as well as the emission properties of the photonic crystals were observed.

The study samples were taken Meliodent self-curing acrylic partial denture acrylics and flexible acrylate Bre.flex, used in manufacturing. The aim of the study was to observe if the irradiation of deployable dentures, there are changes in the structure of the material. Samples were subjected to irradiation at three different values of power (500, 650, and 750 W) and three different time intervals (2, 3, or 5 min), and was later examined by electron microscopy in comparison with control samples of the same material. After the microwave irradiation of materials it is made partial dentures and analysis using scanning electron microscope found no changes notable in the studied areas.

In this paper, some of the ionized forms and aggregated forms of tetrasulphonated porphyrin TPPS4, have been separated by passing it through a composite polymer membranes of polysulfone type with N-methyl-pyrolidone and magnetite. The aqueous solutions of TPPS4 at different pH values have been prepared, characterized and passed through the membrane, leading to the conclusion that the acidic or alkaline solutions have been transformed into neutral form with certain therapeutic properties in photodynamic therapy.

This paper is a brief characterization of composite materials and experimental system used for the measurement of heat transfer in a multilayer Board with the help of thermocouples. Also determine the temperatures, thermal gradients, thermal flows, in stationary mode, within a range of 570 s for a plate of composite materials (aluminium foil, expanded polystyrene, extruded polystyrene, universal adhesive).

Vocal rehabilitation in patients with total laryngectomy can be done by using a phonatory prosthesis. The functioning principle of a speaking prosthesis is based on the existence of one-way valve from the trachea to the esophagus that allows the exhaled air to enter the residual pharynx and produce the voice. One of the possible complications that can occur during this process is represented by the aspiration of the prosthesis into the trachea. The aim of this paper is to present the design of a safety device, made of polydimethylsiloxane, which should prevent the tracheal aspiration of the phonatory prosthesis during primary or secondary insertion or during the replacement procedures.

Drug delivery systems are used to protect unstable pharmaceutical active substances, to modify the characteristics of the loaded drug or to deliver the active ingredient to its specific receptor. In this study, polyurethane-based particles were obtained and the influence of stirring speed during the synthesis, the drying speed of products as well as the chain extender/polyol ratio were determined in order to describe the characteristics of the new particles. The final particles were elongated in shape and stable up to 280oC. We established that the drying speed did not influence in a noticeable manner the particles size and led to the formation of a dispersed system in which the constituents presented a high tendency to form clusters or conglomerates. The results suggested that the stirring speed during the synthesis and the chain extender/polyol ratio may be used as two important parameters which can influence the particles sizes without affecting other characteristics. In vivo evaluation on mice skin model did not reveal any damaging properties of the newly synthesized particles.