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The paper presents the study on the retrieved polyethylene components from total knee prosthesis. For the longevity of total knee arthroplasty it is very important to predict the polyethylene wear and optimize the prosthetic design. The functionality of the total knee prosthesis is affected by contact stress, sliding motion and kinematics of the prosthesis components. The most important factors which cause long-term failure of a prosthetic joint are: macroscopic fracture of the metallic components, polyethylene component wear, corrosion process, and osteolysis. Even the prosthesis development over the past decade has included improvements in implant designs and use of advanced biomaterials, is still difficult to replace some classic biomaterials. Ultra-high molecular-weight polyethylene (UHMWPE) has been the primary material for the articulating surface in prostheses for nearly 40 years. Even now there are a number of problems with the UHMWPE, which cause troubles for the patients. On retrieved polyethylene components, 7 different defects were observed (burnishing, scratching, pitting, surface deformation, delamination, abrasion, bone-cement debris) using stereomicroscopy and scanning electron microscopy. It was found that the cement debris on the surface of the polyethylene explants reduce dramatically the total knee prosthesis lifetime and using FTIR analysis was clearly identified the presence of the cement debris on the surface of polyethylene component. Delamination and abrasion contributed the most to the total amount of damage; according the Hood model, the most damage area of the polyethylene components was seen at the medial (1, 4 sections) and lateral sides (5, 8 sections), followed by the anterior and posterior sides.

The surface of any metallic material, is degradating over time from the repeated impact with the microjets and shock waves generated by the bubbles implosion formed during cavitation. Beside the classical methods of heat or thermochemical treatments, several research institutes and hydromechanical equipments users are oriented to the development of metal-ceramic composite coatings deposited by thermal spraying, to provide good protection from corrosive and erosive action of the liquid medium. The researches from this paper analyse the behavior and resistance to erosion cavitation of a Duplex stainless steel whose surface is coated with WC-9Co-5Cr-1Ni powder, deposited by high velocity oxygen fuel (HVOF) spraying method and followed by laser remelting. These investigations, performed in the Cavitation Laboratory of University Politehnica Timisoara, on the vibratory apparatus with standard piezoceramic crystals, outline the need for remelting the sprayed coating in order to improve its adhesion to the substrate and moreover for growing the mechanical impact resistance with the microjets and shock waves developed during cavitation.

Clostridium difficile infection (CDI) rates in the United States and the world have increased in the last decade, along with associated morbidity and mortality. CDI symptoms can range from mild diarrhea to severe cases including pseudomembranous colitis and toxic mega colon and death. We performed a retrospective study including 130 patients with multiple organ failure who developed Clostridium difficile infection, admitted to the Iasi Sf. Parascheva Infectious Diseases Hospital in the interval January 1st, 2014 – June 1st, 2016; in order to highlight the high incidence of it and showing how we can manage this situations. An increased number of patients with Clostridium difficile infection and multiple organ dysfunction, in 2015 and 2016 was noticed. The profile of the patient from our study is a female with the age over 65 years old, coming from the rural area. Many of the admitted cases were patients enrolled in Hemodialysis Center. Cardiovascular disease was the most common associated pathology (60.79%), followed by renal failure (42%). Charlson comorbidity index showed 3-4, for 97 cases. The specific antibiotherapy for CDI was administrated for 5-7 days to 21 days long. In 73% of the cases the CDI was treated, 17 cases recorded relapse, and one case died. Clostridium difficile is the most common enteric pathogen in hospitalized patients. Standardized procedures to implement hygienic measures and restricted use of antibiotics are necessary to control the widespread occurrence of CDI in immunocompromised renal patients.

Medical devices’ field is developing very fast and the polymers represent next to biocompatible alloys a priority to the research field. The duodenoscopes are intensely used for diagnosis and treatment of various pancreatic and biliary diseases, being in contact with all liquids from saliva, gastric juices and bile liquids. Next to the aggressive environment physical erosion occurs. Using the optical microscopy the superficial polymer coating was analyzed. The deterioration of the coating is increasing the risk of infections and biofilms.

The aim of our study was to investigate the root surface after scaling and root planning (SRP) made with Periotor inserts and contra angle handpiece Profin, comparatively with other two very popular SRP techinques: Gracey curette and ultrasonic piezoelectric scaler with perio-tips. A total number of 30 teeth extracted for periodontal causes were used, 10 teeth for each method of scaling. Samples were examined using ESEM and for each sample micrographs were obtained in four magnifications (× 200 × 1000 × 2000 × 5000). Two examiners blinded to the scaling method but previously trained in evaluating the root surface morphology using RSSL index, examined each micrograph and established a RSSL score. It was considered the highest score for each sample and the average scores were calculated for each group. Lowest scores were obtained by scaling with Periotor inserts followed closely by ultrasonic scaling with perio-tips. Use of Gracey’s curettes left the most extensive areas of dentin denudation and in some samples even traces of scratching. In conclusion, our study highlights that using Periotor inserts for root surface scaling the root surface morphology obtained is the most regular and even with fewest dentin denudation areas.

Polyester-ether polyols were prepared by a clean method, consisting of PET wastes glycolysis with common diols (diethylene glycol and a mixture diethylene gycol/ dipropylene glycol) and a diol derived from biomass (isosorbide) followed by mono-esterification of the glycolyzed products with phthalic anhydride and subsequent propoxylation, under relatively mild conditions. The polyester-ether polyols were characterized by chemical methods, dynamic viscosity measurements, gas chromatography and 1H-MNR spectroscopy. Experiments, conducted in order to test the polyester-ether polyols in rigid polyurethane (PUR) foams formation, showed that the chemical composition of the experimental polyester-ether polyols is fully suitable for reaction with di-isocyanate. The physico-mechanical and flame retardant properties of PUR foams, prepared by using the experimental polyester-ether polyols up to 30% wt. of the polyol component in the foam formulations, were at least similar to the properties of the foam obtained from PET wastes by classical recycling methods. The synthesis method is in agreement with the principles of clean technologies and green chemistry, in the sense that no by-products and no wastes results.

Endoscopic dacryocystorhinostomy (DCR) is a well-established treatment for epiphora caused by anatomic or functional obstruction of the nasolacrimal apparatus. A thorough understanding of the endonasal anatomy, wide marsupialization of the lacrimal sac, and meticulous care for the mucosa are critical for success. Nasal endoscopy has also facilitated the level of performance of the technique. The aim of this paper is to propose a new alternative for the dacryocystorhinostomy (DCR). The use of the new stent with a special design will give the surgeon the ability to keep the stent in the lacrimal duct as long as it is needed.

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.