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The aim of this study was to evaluate the efficiency in using intermaxillary elastics to stimulate mandibular growth and advancement in orthodontic patients diagnosed with skeletal Class II malocclusion as well as to compare the use of these Class II elastics in two different therapeutic approaches. The sample consisted of 60 orthodontic patients aged 10-15 years, 34 girls and 26 boys. The sample was divided into two equal groups (each consisting of 30 patients). Patients belonging to the first group (Group 1) were subjected to 1/4¹¹ - 6.0 oz elastics and were advised to change the elastic every 24 hours. Patients belonging to the second group (Group 2) were subjected to 1/4”- 4.5 oz elastics but with a recommendation to change the elastics every 12 hours. In order to evaluate the effectiveness of these two types of Class II elastics on mandibular growth and advancement, the value of the SNB angle at the beginning of the treatment (T1) was compared with the value of the SNB angle after 5 months of wearing intermaxillary elastics (T2). All patients showed statistically significant increased values of the SNB angle during the orthodontic treatment (p[0.001). Patients in Group 2 showed a significantly higher statistical increase (p[0.05) than patients in Group 1.

The enterprise has an intricate and elaborate system of relationships between the departments, functioning closely as a cell within an organism, with its defined role within the market. In the complex context of actual economic system, resources are limited and enterprises seek for efficiency in order to reduce costs. In this paper we present the development of a solution for the optimization of an agricultural enterprise related to the plastic-based materials usage in the agricultural processes. In this matter, the experimental part consists in the creation of a model of a plastic management system using methodologies from the literature (e. g., System Dynamics or SD etc.) and its simulation with specific tools used traditionally. Besides the experimental part, we will make a short analysis regarding the structural and economic issues regarding plastics used in agriculture and some considerations regarding the bioplastic material that can be obtained from different types of agricultural waste.

It was found that the obtaining of quality 3D printing filaments, without defects and natural color, from corn starch physical modified with PVOH, depends also on the melting behavior at compounding, both of starch and of PVOH, and on the controlling of the process sensitivity of the new compounds. A comparable melting behavior was possible by compounding the two polymers as powders with similar small sized particle. The controlling of the process sensitivity was achievable, mainly, by diminishing the melt resistance to flow, via formulation with a flow agent. The selected compounds which had controlled miscibility, few defects and natural color were shaped, with good results, as filaments with silky and smooth surface. These filaments were compatible with 3D printing because proved to have the ovality and the diameter tolerance in the accepted limits in the fields.

The aim of this study was the development and formulating of an eye contour serum containing hyaluronic acid (HA) and the assessment of stability tests performed for the cosmetic product, transfered into a glass cosmetic bottle with polipropylene (PP) pump and cap. Sample of cosmetic serum were stored using 20 mL glass bottles with PP (Polypropylene) pump and cap. The developed cosmetic formulation was monitored under accelerated stability studies, performed over a period of 30 days while maintaining the product at 4, 20 and 40°C. Quality control initial, and after initiating the accelerated stability test was performed for the developed cosmetic formulation.

Although Romania has a consistent hydro energetic potential, till now is valuated just approximate 30 percent of it. On the big rivers there are already installed high power hydro plants, but a lot of small and medium rivers are not valuated energetically. Installing a new high power hydro plant tends to affect the zone, being necessary a lot of changes in the environment. The Cross-Flow hydraulic turbines don’t need very complex hydro settlements, being very suitable for small and medium power hydro plants. Also a quite big potential in the use this type of hydraulic machines is the energy recovery in the water treatment and sewage plants. The turbine’s blades surfaces enters in contact with the pressurized water jet. The water jet creates a hydrodynamic force that tends to stress the blade. Mainly the Cross-flow turbine blades are made from steel. This article presents the hydrodynamic design and the possibility of using new polymeric material Delrin ®AF for the Cross-Flow turbine runner blades, together with the stress analysis.

The present paper is concerning to an empirical analysis of tensile properties of plies and laminates formed with an epoxy matrix and with various carbon fiber fabrics. The analysis was started with the aim of finding some correlations between the elastic parameters of plies and elastic parameters of laminates when fabrics are used as reinforcements. Six different carbon fiber fabrics were used to analyze the plies and laminates mechanical parameters. The epoxy system Epiphen RE-4020-DE4020 was used in both cases as matrix. The mechanical response to tensile test was analyzed for above mentioned materials and the results had been compared with values obtained by application of various purposed models.

The materials as well as the procedures successfully used in modern restorative dentistry are based on scientific selection criteria which can predict outstanding results both in terms of physiological aspects and durability of the workmanship. The rationale of using certain materials and the success or failure to use certain techniques have contributed in time to the evolution of restorative dentistry. The optimal way of combining the material with its application and finishing technique implies an exhaustive approach to the subject that still requires the specialists’ research and concern for their improvement and development. Among the restorative materials, those that meet the patients’ aesthetic exigencies are the composite resins. In spite of all the advantages resulting from their intrinsic characteristics, it should be noted though that composite resins still have inconveniences related in the first place to the polymerization contraction/shrinkage, which causes a gap between the obturation and the dental tissue further resulting in the generation of marginal micro-infiltrations with all the related drawbacks. Knowing the behavior of the material and understanding its use in various manners can help the practitioner in its efforts to minimize undesirable effects, which is generally possible by applying compensatory clinical techniques. The aim of the experimental research is to evaluate the marginal micro-infiltrations from the class II cavity restorations with composite diacrylic resins according to the different techniques of restoration (stratification technique, flow technique and pre-photopolymerized insert technique) and the establishment of the optimal restorative technique to minimize side effects.

Low velocity impact tests were conducted on quasi-isotropic [±45/0/90o]xs laminates under drop weight impact from 0.7m, corresponding to a 30J energy. In this respect modified epoxy blends reinforced with carbon and Kevlar woven fabrics laminates were developed using autoclave technology. The four configurations developed for low velocity impact tests aimed at investigating several aspects like: the effect of fiber type, stacking sequence and mainly technological processing parameters, on the impact performances. The recorded Load-Time curves were plotted and visual inspection, high resolution laser scanner were used to observe the fracture characteristics of the impacted composite laminates. The results obtained showed that for tested configurations, both stacking sequence and processing parameters directly linked to fiber volume fraction, have a strong effect on the impact performances. The amount of absorbed energy, ductility index was calculated for each configuration under study. The results obtained showed that hybrid configuration exhibits lower stiffness and damage initiation energy amount when compared to carbon reinforced configurations. Nevertheless, their damage propagation energy amount and ductility index was the uppermost. This behaviour was already reported previously [1] and is partially attributed to the higher elastic energy absorption of carbon fibers that delays the propagation of delamination, and fiber breakage. Lower tenacity obtained on hybrid laminates was attributed to both lack of resin local rinse saturate and to the intrinsic anisotropy of para-aramid fibers.

Carbapenem antibiotics resistance is a medical threat in antibacterial therapy as the pathogen resistant strains easily evolve a multi-drug resistance action to other incurable agents. The protective transport of current antibiotic molecules using nano-carriers initiates a huge approach in the antibacterial therapy, allowing the nanohybrids to defeat all these health threat pathogen agents. Chitosan is a linear cationic polysaccharide being often used in medical area as a biocompatible encapsulating agent in antibiotic delivery nanosystems. This work refers to encapsulation of imipenem into biodegradable chitosan nanoparticles in order to destroy antibiotic-resistant bacteria and limit the microbial adhesion and multiplication. Nanoparticles were prepared by ion gelation method using tripolyphosphate as cross linking agent. The obtained hybrid nanocapsules were then characterized and evaluated as a potential nano-device to beat antimicrobial resistance.

The usual treatment for tuberculosis is difficult by its long-term therapy, raised dosing frequency and adverse effects of anti-tuberculosis drugs. Anionic clays, also called layered double hydroxides are a class of hydrotalcite like structures having high compositional variety and being able to self-assembly in the presence of drug molecules. The work refers to the development of nanohybrid materials like delivery systems that intercalates isonicotinic acid hydrazide, known as isoniazid anti-tuberculosis drug, into layered structure of hydrotalcite compounds. Loaded drug molecules of isoniazid were proved to be released in a controlled way from the as synthesized nanostructure in a simulated buffer solution. The obtained sample was characterized by advanced techniques thus demonstrating the inclusion of isoniazid antibiotic between hydrotalcite sheets. These results revealed important expectations for further researches of these organic-inorganic nanocomposites for tuberculosis treatment.