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Ultra-High Molecular Weight Polyethylene (UHMWPE) composites are the result of recent developments in material research for ballistic protection due to their ability to absorb the kinetic energy of the bullet by various mechanisms of dissipation, among which an important one is delamination. In order to study this mechanism independently, the laser induced shock wave testing procedure has been used on thin Tensylon® laminate samples. Laser-induced shock represents a modern approach that can be used for assessing the interlaminar bond strength between two plies of a composite material, in dynamic conditions, at high strain rates representative for a ballistic impact. Through this technique, a delamination failure stress threshold can be determined. In the present work, the laser induced shock technique was applied on the commercial UHMWPE material called Tensylon®. The delamination threshold of this material was determined by using the Novikov approach, and, compared to the literature, the results match the values determined by other means of measurement.

Skin- and mucosal infections, especially purulent, can often cause diagnostic and treatment problems. Therefore, we intend to conduct a microbiological study of isolated bacterial strains from ambulatory patients with various cutaneous-mucosal infections. In isolated strains we determined the sensitivity to antibiotics and we established the phenotypes of resistance in which they fall. We took in account 98 strains isolated by a private laboratory in Timisoara between January 2016 and December 2017. After bacterial identification, sensitivity testing to antibiotics was realized using Kirby-Bauer disc diffusion according to the CLSI standard. Antibiogram was performed for all strains except for Streptococcus pyogenes. By interpreting the antibiograms, the phenotypes of resistance were determined. Most infections were caused by Staphylococcus aureus. In order of frequency following strains were isolated: Staphylococcus aureus (75.52%), Streptococcus pyogenes (11.22%), Pseudomonas aeruginosa (7.14%), E. coli (4.08%) ’i Enterobacter spp. (2.04%). S. aureus strains were resistant to penicillin in 94.60% of cases. We observed a higher sensitivity to oxacillin (87.84%), tobramycin (86.49%), gentamycin (87.84%), ciprofloxacin (83.78%) and clindamycin (89.20%). Most strains of S. aureus were of phenotype Peni-R Meti-S (82.44%). 12.16% were of phenotype Peni-R Meti-R (MRSA) and only 5.40% were sensitive to betalactams (Peni-S Meti-S). Gram-negative bacilli strains (Pseudomonas aeruginosa, E. coli, Enterobacter spp.) were less resistant, all being wild strains. Determining antibiotic resistance phenotypes is necessary in order to be able to make the right decision when choosing anti-infectious treatment, but also to prevent the selection of multi-resistant bacterial strains. The presence of MRSA at a rate of 12.16% is an alarm signal because the MRSA strains are multi-resistant to antibiotics with cross-resistance to the betalactams. Resistance usualy extends also to other classes of antibiotics. For a correct diagnosis and treatment, the results of the bacteriological testing need to be corroborated with the clinical signs.

The objective of this in-vitro study was to compare if there are any differences in the marginal fit of crowns fabricated by CAD/CAM technique. We used three different types of materials (two types of polymethylmetacrylate (PMMA) provided by two different manufacturers and one type of hybrid ceramic) and three different types of impressions: intraoral scanning, model scanning and conventional impression scanning. The crowns were subsequently measured with an electronic microscope at 1000X. Our results showed better results for the hybrid ceramic. The differences between the PMMA were not significant. There were no statistic differences with the ANOVA analysis between the scanning methods. Best combination in terms of marginal fit was found with hybrid ceramic and intraoral scanning.

The incidence of postoperative pain in patients operated for inguinal hernia can reach up to 40% of cases, depending on different authors, and depending on the approach used in the surgical treatment of these patients. Currently, there are two commonly accepted ways of surgical treatment of inguinal hernias, the classic approach with polypropylene mesh (Liechtenstein technique) and the laparoscopic approach. The purpose of this study was to conduct a comparative analysis on the need for analgesic medication in patients treated for inguinal hernia either by classic (group A) or by laparoscopic (group B) approach. Surgical meshes were used in all patients enrolled in our trial. The average age of the patients included in this study was 53.79 years, ranging from 20 to 88 years. Regarding the distribution of cases by gender, we observed in the studied lots that 12 cases were women (11.53%) and 92 cases were males (88.46%). In female patients, the classic inguinal hernia approach was performed in 3 cases (25% of cases), and in 9 cases the laparoscopic approach was performed in the surgical treatment of the inguinal hernia (75% of the cases). In male patients, laparoscopic approach was performed in 33 cases (35.86% of cases), and in 59 cases the surgical approach was performed in a classical manner using the Liechtenstein technique (64.13% of the cases). From the statistical analysis of the data we noticed a statistically significant difference in the need for analgesic medication administered to these patients (p = 0.0001). Although surgical correction of inguinal hernia, both classic and laparoscopic approaches, provide adequate treatment for these patients, in case of the laparoscopic technique, immediately after the operation, the need for analgesic medication is lower compared to the classical technique.

The phytotherapy is based on the consume of fruits, vegetables and medicinal plants; they contain mixtures of bioactive chemical substances (carotenoids, phenolic acids, flavonoids, coumarins, tannins, organosulfur compounds) with synergic effects on the treatment of diseases. Nano- and micro-carriers are very useful drug delivery systems which can improve the transmembrane transfer of natural extracts. In the present study, betulin and two birch bark extracts were encapsulated inside polyurethane microstructures. Structures’ size, homogeneity and surface charge were studied using a Zetasizer, while DSC analysis was involved to assay structures’ thermal behavior. Irritation effects were monitored by non-invasive techniques on human skin. The results indicate the obtaining of structures with size around 200-250 nm, with a positive surface charge and a very good thermal stability. The non-irritation potential recommends these structures as a safe delivery system used for natural extracts.

The paper presents the laboratory experiments and the results obtained regarding the production and characterization of composite materials with coconut fiber for the manufacture of brake pads for small vehicles and medium performances. The experimental research of composite material with organic components determined the influence of some material factors and parameters of the sintering regime on the physico-mechanical characteristics of the tested samples. Knowledge of these characteristics offers the possibility of pertinent appraisals regarding the behaviour of the composite materials intended for used in brake pads applications. Materials with the best features will be selected to determine the functional characteristics of friction and wear.

In most patients with complete or partially stretched edentations requiring a dental implant, there is insufficient alveolar bone for a proper morpho- functional prosthetic restoration. Therefore, in many cases a bone addition is required for the implant treatment. The aim of this study is to evaluate ex-vivo, with numerical simulations, a large mandibular bone defect that is restored by using a three-dimensional (3D) printed ceramic scaffold. In order to obtain a proper morphological and functional prosthetic restoration, a thick mandibular bone is utilized for the implant treatment. The polymeric scaffold is attached to the mandibular bone with one, two, or three implants. By scanning the mandible with MicroScribe 3G and then employing a Finite Element Analysis (FEA) with Pro/Engineer and ANSYS 15, the study performs a numerical simulation and thus assesses the effects of the force applied to the scaffold.

A class of intensively studied materials with application in areas where complex structures with precise geometry are needed (i.e. electronics), are the self-organized nanomaterials. Polymer, metallic and composite self-organized nanomaterials have been in researchers’ attention the last decades. They are not only appealing scientifically, by revealing the intrinsic atomic and molecular interactions that might be difficult to detect otherwise but may also hold the key for the development of novel functional structures and devices. The different mechanisms and forces involved in the self-formation of organized nanostructures are discussed in the present manuscript. Further on, key formation fundamentals involved in the fabrication of self-organized nanostructures are described. Between the known manufacturing methods, the electrochemical synthesis is considered extremely simple and cost effective. On the other hand, it involves a wide range of synthesis parameters (e.g. voltage, electrolyte type, temperature, experiment duration, pH etc.) that may lead to the formation of ingenious structures with complex geometries at different length scales. Finally, some representative scientific investigations are mentioned together with applications of self-organized nanomaterials in different engineering and life areas.

The experimental results obtained by studying the influence of different types of fibers on the mechanical properties of fly ash polymer concrete are presented in the paper. The general demand of using wastes found applicability in building material industry because some of them are beneficial in improving concrete properties. The waste additions type fly ash and fibers were incorporated in polymer concrete. The study focused on fibers type glass, polyester, metallic and cellulose. The mechanical properties such as compressive strength, flexural strength and split tensile strength were investigated having in view the type, dosage and length of fibers. The results show that fibers improved mechanical properties in comparison with that of polymer concrete without fibers, the test results being differently influenced by the factors which were considered.

Composites made from metallic fillers embedded in polymer matrix have good shielding properties as electrical point of view and tribology properties from mechanical point of view. These properties depend on amounts, shapes, sizes, and combinations of fillers and matrix. This paper proposes an electromagnetic method for determination of metallic fillers concentration in composite materials from metallic fillers embedded in polyester matrix. The bulk resistivity and dielectric permittivity were measured but these measurements are less influenced by the fillers concentration. The amplitude measurement of e.m.f induced in the reception coil of the focalized electromagnetic transducer and their averaging for the scanning of a relative large zone of the composite has proven to be an efficient method. The average amplitude linearly decreases with the increasing of fillers concentration, and has different values for Cu and AISI 316 fillers.