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The aim of this study was the encapsulation of ginger essential oil in polymer particles. The chosen method was suspension polymerization of methyl methacrylate. In all cases, the polymerization process in the presence of ginger essential oil leads to decrease of the conversion at similar reaction intervals. The different reactivity of the essential oil components towards the free radicals generated by the thermal decomposition of AIBN was determined using GC/MS headspace analysis. The amount of encapsulated oil was determined by thermogravimetrical and GC analyses. TGA provided less reliable data about the total encapsulated essential oil. However, the extraction and GC analysis of the samples confirmed a higher content of essential oil in sample 2 (0.03 mol/L AIBN), and the lowest in sample 4 (0.09 mol/L AIBN).

Utilization of relatively simple devices fitted for the ring frames permits the realization of yarns with filamentary elastomer core. The aspect of yarns is similar with that of the classical yarns, but their structure and characteristics are very different. Depending on the core-sheath combination, filaments and fibers nature and characteristics, the quota of components participation, yarn twisting degree etc., the range of these yarns assortment is practically unlimited. Due to the large capacity of deformation and recovery of the elastomer filaments, the classical methodologies used to determine the classical yarns characteristics cannot be applied to the elastomer-containing yarns, and these yarns show specific indicators for characteristics assessment. This work presents a synthesis of some ample researches on the methods and characteristics of wool-type yarns with elastomer core, as well as the transfer of elastomer filament characteristics to the composite yarns that contain elastomer.

When we talk about plastic industry, then one of the most important aspects of this trade is giving the plastic its bright and attractive color. As more and more people crave for the “return to nature” touch, pigments extracted from vegetal materials considered as waste have been analysed for dyeing textiles and manufacturing colorants for painting. Senescent leaves of Vitis vinifera L. have been tested for their capability of extracting organic pigments (chlorophyll, carotenoids, xanthophylls and anthocyans). The results show that the potential exists, further research is needed in order to best develop the methodologies needed.

Virtual-patient (VP) software is an innovative educational tool which provides a safe environment in which students and interns can acquire clinical skills before engaging in real patient cases. Virtual patients allow the study of different scenarios regardless of the teaching staff availability, student location or, more important in dentistry, accessibility to patient, dental materials and different technologies. Considering the high standards of nowadays dentistry and, unfortunately, the limited possibilities in university clinics, the young doctors might find themselves in front of an overwhelming dilemma concerning material selection, appropriate technique and technology. The aim was to assess the qualitative general impact of VPs on dentistry students and the qualitative impact of two virtual clinical cases in particular, focusing on the selection of dental materials and on the suitable technology. 73 students participated in this study. The study comprised 5 stages: answer to an initial questionnaire regarding the students’ previous experience with VP software and their expectations related to the VP characteristics; incorporate the results of the initial questionnaire into building the two mentioned virtual cases; use built VPs in student training; answer to a final questionnaire recording the student feed-back to the VPs used; corroborate results from the two questionnaires to establish relevant qualitative features for VPs in dentistry. The results of the study are an important feed-back tool helping in developing and refining VPs with a high degree of acceptance, maximizing the educational efficiency of this learning method. Some of the most desired characteristics were: multimedia content, feed-back for good and bad decisions, low to medium degree of complexity, high coverage of course subjects. The use of VPs offers the chance of working with a broad range of dental materials (in a simulated mode) which is not normally possible in a real practice constrained by financial restrictions.

This study analyzed the lead behavior from CRT glass embedded in original composite materials exposed to different pH and temperature conditions. For this study were obtained composite materials with CRT glass (funnel) waste, some of them with zeolite addition, for lead chelating. The experimental results showed the pH and temperature influence lead leachability during the ultrasonic procedure and explained the influence of zeolites in lead behavior.

Injected plastic parts with internal threads (round, trapezoidal or saw) can increase products functionality but if not carefully designed can add unforeseen costs into the manufacturing process. In this paper the authors presents a computation methodology of the demolding moment for two cases of plastic injected parts with internal saw thread. This key parameter of the injection process directly influences the design solution of the ejector system. As further work the author will try to validate this method through a set of practical experiments.

The paper features several one-dimensional models to represent the rubber springs used in the dynamics simulations for the railway vehicles. Similarly, it includes a description of a model for the illustration of the mechanical behaviour of a mix coil spring - rubber employed in the secondary suspension of the passenger cars. The principle of this model relies on the overlapping of three components – elastic, viscous and the dry friction. The dependence of the force developed in the mix coil spring - rubber on the frequency and amplitude of a harmonic excitation is highlighted via the numerical simulations.

In the light of multiple research on dental erosion, by using the spectrophotometry absorption method, we have conducted a in vitro study with the aim to highlight the erosive effect of chlorinated pool water, as well as the protective role of a lacquer and of two different toothpastes with remineralizant effect. Followed targets: the erosive capacity evaluation of three chlorinated waters used for swimming pools, the quantitative determination of the calcium and phosphates concentration absorbed by these waters, the quantitative determination of the remineralization and protection capacity of some dental materials on the enamel exposed to the action of chlorinated waters. After exposing the enamel to the action of these waters, we determined that the swimming pool waters improperly chlorinated represent a risk factor for the performant and casual swimmers. These waters have the capacity to demineralize the dental enamel in vitro, the severity of the demineralization being influenced by the pH and the capacity of extracting different quantities of calcium and phosphates. The three materials used for protection are able to remineralize the dental enamel, the best effect being given by the application of fluorinated lacquers. Optimal maintenance strategies of the swimming pools and specific prophylactic methods for the performant swimmers are necessary.

Genu valgum or valgus knee is a disorder caused by the knee deviation in the frontal plane, when the external angle formed between the thigh and calf is less than 170 degrees. The incidence of this disorder is unknown; it can occur sporadically or inside the family and it is one of the most common causes of joint pain. This study describes the properties and the application of a commercial material, AliPlast™ 10, in the case of a 13-year-old patient which presents bilaterally genu valgum deviations. Important improvement in gait and posture were obtained after a 6 months treatment, in which the patient has used the orthoses, combined with physical therapy.

The superstructure of dental implants represents the portion that is attached to the implant substructure, by a fixed or movable prosthetic restoration, realized in order to restore the disturbed functions oro-facial system. Recently, a new high performance polymer, BioHPP, based on polyether-ether-ketone (PEEK) polymer was introduced as dental material for manufacturing the superstructure dentures on dental implants. The purpose of this article is to present the results of the clinical trials referring to the advantages of BioHPP polymer as superstructure in oral implantology. The research has been carried out on 35 patients. The recordings of the advantages in the using this polymer for superstructure on dental implants, in accordance with six evaluation criteria, were performed in three dental schools from Romania, monthly, during one year. The results of survey demonstrate that BioHPP polymer as superstructure on dental implants present many advantages, therefore this PEEK type of dental material represents a beneficial new acquisition for patients’ oral health.