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The present article is the first in a series of three articles presenting results obtained by our team in a study on sandwich composite materials. The aim was to study the damping capacity of some sandwich structures used for a structural element of a machine tool that was reduced to scale (namely, a column), as well as all aspects of the material’s recyclability. The first stage of the study involved the characterization of the Polypad® composite material by scanning electron microscopy (SEM) coupled with energy dispersive X-ray spectrometry (EDX), Fourier transform infrared spectrometry (FTIR) and X-ray diffraction (XRD).

Using special materials with a reverse geometry for contact lenses is named orthokeratology. It is a non-surgical modern medical alternative to conventional contact lenses for correction of myopia. Orthokeratology is an alternative treatment for patients with progressive myopia, especially children. The contact lenses is using during the night for minimum 6 h. With these special contact lenses children can be treated after 18 years old with refractive corneal surgery. The materials of night contact lens are gas permeable and permit progressive aplanation of central cornea, which induced decreasing of myopia or myopic astigmatism. The purpose for this study is to prove the effectiveness in improving of the quality of vision using night contact lens. The study also monitored the effectiveness of orthokerathology as a preventive method for amblyopia in myopic or astigmatic patients.

As a result of the requirement to achieve the implementation of the European Water Framework Directive (WFD) in all the member states by 2015, Romanian’s water management policies need to carefully look and consider water quality issues. All waters will achieve a good ecological status, therefore simulation of the existing status of the water bodies and analysis of proper adaptation measures for improving water quality is an important part of the implementation process. Water quality models play an essential role in support of the water management decisions. Present paper presents an application of the DHI tool, Mike 11, for the simulation of water quantity and quality of Bega River. The evolution of a pollutant source is traced both in time and space on a segment of the Bega River, from Topolovat to Otelec. The obtained results show that model is able to capture the water quality of the river, as per the observed values, and it is possible to be used in the future to predict the impact of a certain pollutant on the Bega River. The results of this study show the possibility to develop what-if analyses, which can help decision makers to choose the best adaptation strategy.

Bone regeneration remains an important challenge for research trends in dentistry. In this study, the authors analyse the effect of the membrane composition for the results of bone grafting.They used in 30 cases, collagen and polytetrafluoroethylene membranes. The dehiscences was bigger in case with PTFE membranes.

Banat River Area specific climate is characterized by moderate temperature and high precipitation amounts, which affect the surface water quality. Since Secu Lake, located on Valley Bârzava provides drinking water to Reºiþa city, the raw water turbidity variation was analyzed depending on changes in climatic parameters. The study is based on monitored values of this quality indicator, within two years (December 2008-December 2010). Deviations from normal climatic limits are frequently caused by CO2 concentration increasing in the atmosphere and massive deforestation determined during the analyzed period, increases in rainfall, with influences on the Lake Secu water turbidity. On the other hand, the works on the Bârzava River course, have contributed to changes in turbidity, by dislodging sand, gravel and various residues. Analysis of this indicator was performed in order to assess the water quality and the necessity of drinking water correction.

This study aim to compare the root surface morphology after scaling with Gracey’s curette, ultrasonic tip, Periotor insert, using Atomic Force Microscopy (AFM). For every tooth have been analysed three different zones on the surface and for every zone we investigated concentric foursquare areas with the size of 0.5 / 1 / 2 / 5 / 10 / 20 mm. For every area, bi-dimensional-2D and three-dimensional-3D images, phase contrast and statistical parameters have been registered. Both ways to analyse data: directly, by the images comparing and the statistics revealed a more appropriate surface morphology obtained after scaling with Periotor inserts, followed by Gracey’s curette and ultrasonic tip, which were approximately simillar in features. Acknowledgment: this study was made within UMF-Iasi Internal Grant 30879/30.12.2014.

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.