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This paper presents the development of dynamically cured polymer composites and nanocomposites based on plastomer - PP (polypropylene) and EPDM elastomer (ethylene-propylene-diene-terpolymer) compatibilized and reinforced with nanometric particles-MMT (montmorillonite, chemically modified layered clay) in two stages, by extrusion-granulation and mixing. Nanoparticles increase the thermal resistance of dynamically cured polymer nanocomposites. By means of compatibilization and dynamic curing, elastomer particles - EPDM are more easily dispersed in the mixture. The materials obtained were tested physicomechanically (Melt Flow Index) and morpho-structurally (FT-IR and DSC).

Gene therapy represents a promising method for treating genetic disorders or diseases consisting in the transfer of genetic material (DNA) to cells in order to substitute or to slow down the evolution of the defective gene in cells. Theoretical models to predict DNA release are difficult to build in the classical approach of continuous and differentiable physical quantities, due to the high number of interdependent phenomena that occur simultaneous. The article presents a theoretical model based on the fractal theory of motions in the form of Scale Relativity Theory to describe nonlinear behaviors in gene therapy. Correlations of the theoretical model with experimental data are also observed.

Over time, anatomists have been concerned with the preservation of anatomical parts for a long time. Thus, in the modern era, both colouring and fixing substances, as well as plastic and corrosive materials have been used in the manufacture of corrosion and plastinated specimens. The ultimate aim was to make the dissected anatomical specimens as lasting and accurate as possible. Thus, parenchymal viscera, which have a certain tissue thickness, greater than in the tubular viscera, are more difficult to preserve and obviously to dissect. The time required to preserve those increases accordingly. In our study we have used 62 formalized adult human kidneys, belonging to 31 bilateral dissected bodies, different age and gender, 20 males and 11 females. We have removed all the kidneys from the renal fossa and we have made 23 corrosion casts, and 39 specimens have been plastinated. There have been dissected 30 structures considered as normal in size and morphological aspect and 9 have been preserved entirely because they did not fit within the normal physiological limits. All 39 kidneys have been undergone to S10 Biodur rubber silicone technique preservation.

Uterine sarcomas are rare but very aggressive gynecologic malignancies. The most frequent signs and symptoms at the moment of diagnosis include abnormal uterine bleeding or diffuse abdomino-pelvic pains while acute abdomen by uterine rupture is an uncommon situation. We present the case of a 72 year old patient who presented in emergency for diffuse abdominal pain and hypotension. An emergency laparotomy was performed and a ruptured uterine tumor with small bowel and sigmoidian serosal invasion and intra-peritoneal bleeding was found. The tumor was resected en bloc with total hysterectomy, bilateral adnexectomy, segmental enterectomy and sigmoidectomy, pelvic and para-aortic lymph node dissection. The histopathological and immunohistochemistry examination revealed a poorly differentiated sarcoma. Although it is a rare condition, a uterine sarcoma can rupture and cause hemoperitoneum; emergency surgery while respecting oncologic principles of complete resection is mandatory.

This paper presents a study on the behaviour of composites based on natural rubber and plasticized starch after aging under temperate climate conditions. Natural rubber blends containing different amounts of glycerine-plasticized starch as biodegradable filler were made. Analysis of samples after being kept for 1 year in temperate weather conditions shows a change in the surface of vulcanizates due to the influence of atmospheric factors. Surface oxidation and degradation was highlighted by: FTIR analysis (appearance of -OH, -COOH groups, etc.), SEM microscopy (appearance of cracks on the surface), immersion in water. The degradation of the materials is also highlighted by the decrease of the physical-mechanical properties, the gel fraction and crosslinking degree. The best aging behaviour was observed in the mixture containing a low amount of biodegradable starch and the worst behaviour was that of the control starch-free mixture.

In this paper is studied the hot plastic deformability (plasticity and resistance to deformation) for the low-alloyed steel of heat treatment for mechanical engineering in two ways: compression and tension. Groups of low alloy steels is very important in terms of quality and quantity, the products of these steels have developed internal and external market. The plasticity variation were plotted with the temperature and it was established that the plasticity of the steel increases in the range 700-12000C, then decreases as a result of the firing of the grain boundaries, for the bars obtained from ingot and continuous cast blown it was noticed that the plasticity values are very close. Deformation resistance decreases as the temperature increases. The finest granulation was obtained for a final plastic deformation temperature of 8000C and a minimum degree of deformation of 45%.

The aim of this in vitro study is to compare the load-to-fracture performance of polymethyl methacrylates (PMMA) provisional restorations manufactured with a traditional laboratory technique in comparison to a computer-assisted design and computer-assisted manufacturing (CAD-CAM) technique. Five interim three-unit fixed dental prostheses were fabricated with the conventional indirect technique, on a standard typodont. The same model was scanned with an intraoral scanner and the digital design of identical fixed dental prostheses was made. Then other five interim three-unit fixed dental prostheses were milled from PMMA CAD/CAM blocks with an in office milling machine. All specimens were tested for flexural strength in a universal testing machine, and the maximum load to fracture was measured. For the conventional provisional restorations, the load to fracture was 121.16 ± 24.6, in comparison to CAD/CAM interim restorations, for which the load to fracture was 728.88 ± 228.7. Within the limitations of this study, one can conclude that CAD/CAM provisional restorations present a higher fracture load than the conventional manufactured interim restorations.

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.