The objective of the study is the low-pressure membrane process for treating aqueous solutions containing synthetic food dye (E104 – quinoline yellow). Dye concentration used was 10% (equivalent to 100g/m3). The pressures used in the ultrafiltration process were 0.1, 0.2 and 0.3 MPa. Experiments were performed in dead - end instalations in which the effectiveness of the polysulfone - alkylbenzyldimethylammonium chloride (PSU-ABDMA) and polysulfone - N-dodecylpyridinium chloride (PSU - NDPCl) were tested. The efficiency of these membranes has been proved by calculating the permeate flow and the retention. Analyzing the experimental data, it was found that for the polysulfone-alkylbenzyldimethylammonium chloride composite membrane the degree of retention is completely different, with high values being obtained for low pressures and low values for high pressures used.
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The present paper presents the results of the research regarding the bolus structure (Bio-Rad Win-IR instrument), the elasticity modulus, the bioadhesiveness properties (TA-XT2 Plus analyzer) and the clinical applications of the bolus in the adjuvant irradiation after radical mastectomy (Treatment Plan System Eclipse). The dose-volume histogram has made a comparative evaluation for with and without bolus treatment plans and confirmed the importance of bolus utilisation in selected patients. Conclusions: the thickness of the applied bolus is dependent on the skin dose required, on the treatment technique and must be equal to the depth of the build-up region for the removal of the skin-sparing effect of a high energy radiation.
The influence of Ag/SiO2 as nanofiller and sodium oleate as compatibilizer and their mixtures on the patterns flow and structure formation processes in thermodynamically incompatible polypropylene/plasticized polyvinylalcohol (PP / PVA) systems were studied. It is found that the change in the sequence of mixing the ingredients of the composition allows adjusting the morphology phase type due to the predominant localization of nanoparticle additives in the melt amount of a component or on the border of phase separation. Injection of Ag/SiO2 to melt PP increases dispersion degree and homogeneity of its distribution in the matrix. Simultaneous use of nanoadditive and sodium oleate as compatibilizer improves the connections between the polymers and promotes thinner and more homogeneous dispersion of the particles of the dispersed phase. It is shown that the effective viscosity of melt nanofilled system is determined by components mixing method: viscosity of melt blend increases when the additive is localized predominantly in the PVA and decreases with the prior injection of PP. The nature of the flow for all researched compositions obeys a power law and almost does not depend on the method of mixing. The ability of the longitudinal deformation of ternary blends is deteriorating, but remains sufficient for their processing. Combining nanoadditive with compatibilizer promotes increased elasticity and the melt spinnability of modified blends.
Root decay is a complex and multifactorial disease. The aim of this study is to assess in vitro the sealing capacity of common aesthetic materials used to restore root caries as well as the size of the hybrid layer formed by SE-1 step vs 2-step ER adhesive techniques. For this study, 45 extracted teeth were used. After cleaning, near the enamel-cement junction, but at the level of the cementum, cavities were prepared and restored with resin composite, giomer and glass-ionomer cements. The teeth were covered with nail polish leaving uncovered the restoration area and 2mm around it; teeth were kept for 24 h , in 2% methylene blue. To assess the degree of marginal adaptation, SEM analysis was further performed. The association of 2-step ER adhesive system with giomers and resin composite shows the maximum adhesion efficiency by forming a uniform, thick layer and dentinal tubules obliteration compared to SE-1 step adhesive system associated with the same restoration materials.
A moment of permeation of both gaseous and liquid phases of a toxic compound through a barrier material has been indicated colorimetrically at the same time on 20 exposed places using suitable colour indicators. The newly developed device MINITEST is able to evaluate the resistivity of both porous and non-porous barrier materials of a textile character against permeation of toxic vapours (permeation) and liquids (penetration) in static conditions. As a model test chemical either the sulfur mustard or significantly alkaline or acid volatile toxic compound have been applied. During the permeation, these species react with a suitable acid-base indicator and a markedly coloured stain can be created. Newly developed MINITEST device enables determination of chemical resistance of areal barrier materials not only in a process of their development but also in the rate of their practical applications.
Procalcitonin was proposed to have been a more specific and better value compared to CRP as a marker of prognosis, although its diagnostic value is also contested.This study was conducted in the Department of Neonatology and the Department of Obstetrics and Gynecology of “Pius Brînzeu” Emergency County Hospital Timisoara on a group of 20 newborns coming from 20 mothers that have been found with low procalcitonin. The gestational age at birth was 36-39 weeks. PCT values do not correlate and do not indicate correctly viral infections. Serum PCT levels must be interpreted within the clinical setting; there are many other causes that could lead to its growth. Our study consists of two different parts. In the first part we computed a regression model in order to see if there is any association between the vales of procalcitonin obtained from the blood analysis of the mother and the procalcitonin of her child.
Traditionally, removable partial dentures consist of a metallic framework, covered by acrylic saddles, which support acrylic or ceramic teeth. Because their shortcomings, new classes of resins/macromolecular compounds which promise better quality are nowadays available for manufacturing removable partial dentures: urethane-based resins, polyamides, acetal resins, high-performance polymers. Manufacturing these new materials implies alternative technologies like: injection, milling, light-curing. Using these alternative polymeric materials results in dentures with better resistance, elasticity, appearance and lower weight, which provide much more comfort to the patient.
Treatment of impacted teeth often implies placing a bonded attachment and using orthodontic forces to move the tooth into occlusion. The aim of the paper is to describe a novel methodology of manufacturing orthodontic attachments for impacted teeth using the latest CAD software and 3D printing technology. A biocompatible acrylic based resin was used to print a custom made attachment designed based on the volumetric data aquired through cone bean computer tomography. Custom design of the attachment simplified clinical insertion and treatment planning and 3D printing made its manufacturing easier. Being a first trial, more reasearch is needed to improve the methodology and materials used.
An important influence factor for the plasticity of the low carbon steels is the cooling speed value after heating treatment. It is important to be chooses the optimal cooling regime for these materials because the steels have been laminated at high temperature or, the steels have been heated at high temperature after lamination process. There were considered two groups of samples of two low carbon steels, each group had eight samples. Three different mediums for directing of the cooling process were considered and the properties of the steels have been modified. After an experimental program, the values obtained were used to determine the variation between these variables corresponding to two kinds of steels (coded: Steel 1 and Steel 2).
The intraosseous implants are the most used dental implants. The development of new classes of dental biomaterials determined the apparition of Trinia, a Computer-Aided Design/Computer-Aided Manufacturing (CAD/CAM) reinforced polymer, used for core in non-metallic prosthetic restorations, including implants superstructure. The aim of the study was to present the obtained results in the use of Trinia polymer as non-metallic core on the abutments of Bicon implants. 35 patients were selected, 19 females and 16 males, aged between 31 and 60 years. After 18 months of results monitoring, we ascertained that Trinia reinforced polymer had a very good behavior in the oral cavity, and the patients did not complain about inconveniences due to the oral rehabilitation with this biopolymer.