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In recent years, the inorganic nanoparticles played an important role in the membrane technology due to their special properties, most notably being the hydrophilicity/hydrophobicity modification of the active surface of the membrane. In this paper, the polymer used for membrane manufacturing was polysulfone (PSf) via phase-inversion method. The composite PSf membranes were prepared by blending zinc oxide (ZnO), titanium dioxide (TiO2) nanoparticles and ZnO/TiO2 nanohybrid with three concentrations. Retention of Congo red dye, distilled water permeability, relative flux and relative flux reduction were tested in order to study the effects of the nanoparticles in the membrane matrix. SEM, EDX, porosity, roughness, contact angle, tensile strength and elongation measurement were conducted in this article, also. Compared with control PSf, ZnO/PSf and TiO2/PSf membranes, the experimental results indicated that the ZnO/TiO2/PSf nanohybrid membrane presents the best overall properties, including permeability, retention, and antifouling ability. ZnO/TiO2/PSf membrane exhibits a percentage increase in permeability of 254% and retention of 64.58 % relative to that of the control PSf membrane.

The seven curcumin derivatives were deposited on palygorskite in order to obtain hybrid materials. The fluorescence emission spectra of the obtained materials show a decrease in fluorescence intensity relative to the respective dyes, due to the environments around the dyestuff molecules created in the host matrices. Absorption studies show the best adsorption on the inorganic matrix, for the compounds with the hydroxyl groups. Correlating fluorescence spectra of hybrid materials with the results for absorption spectra of the dyes adsorbtion on the surface of the clay lead to the conclusion that a high percentage of the adsorbed dye had the effect of fluorescence quenching. Thus, it was confirmed that the fluorescent properties of hybrid materials depend on the interactions established between the fluorescent dyestuff and the inorganic network.

The present paper reports the first attempt to synthesize bicomponent hydrogels based on methacryloyl derivatives of gelatin (GelMA) and mucin (MuMA) with different compositions, with potential as wound dressings. While gelatin is widely investigated and used to fabricate scaffolds and coatings stimulating cell interactions and tissue regeneration, mucin - a macromolecule which covers the wet epithelia - remains yet under exploited as biomaterial. The influence of MuMA content on various parameters such as the affinity for aqueous media, stability in simulated physiologic media and the rheologic behavior was investigated. Also, the preliminary assessment of the drug release potential and biocompatibility were performed. The materials’ water uptake capacity and rheologic behavior depend on the pH value of the incubation media, while their composition influences the drug release capacity and cells-scaffold interactions.

This work presents some of researches performed by the authors on execution of plastic parts required for repair works specific to certain machines and plants. Authors focused especially on the repair and reconditioning of certain assemblies which include various machine parts: special spacers, machine-tools guides and toothed gears. Methods shown herein are very simple, accessible even to small workshop and they do not require special equipment, thereby involving minimal expenses. The use of simple programs allow fast and low-cost execution of parts with an accurately determined geometry.

Prosthetic mesh implants in hernia repair are frequently used based on the fact that lower recurrence rates are detected compared to anatomic repair. In latest years, researchers tried to answer weather there is an ideal mesh material for abdominal hernia repair. The studies tried to compare resistance, bio-tolerance, rates of recurrence and infection of several materials used in alloplasty. The results are far from pointing an unique ideal chemical structure of mesh. In our study, we compared the results of a cohort of 265 patients operated in 2010 and 2011 in our clinic for complicated abdominal incisional hernias. We compared the results of polypropylene mesh vs. polyester. Polypropylene mesh proved significantly better for preventing hernia recurrence and showed a lower shrinkage rate.

Combining technological development in the laparoscopic field alongside the increase of surgeon’s experience in partial nephrectomy, have extended the indications of laparoscopic nephron sparing surgery to more complicated cases, increasing the role of suture materials in obtaining a good collecting system closure and hemostasis, with short warm ischemia time and low postoperative complications rate. Suturing materials are continuously developed combining new and unique designs with novel synthetic materials in order to fulfill surgeon’s exigence.

The aim of the paper is to identify the of optimal plastic type used in obtaining thoraco-lumbar orthoses - used in the treatments of comminutive fracture, of burst fracture type of the vertebrae in the lumbar area. For this purpose, with the help of Finite Element Analysis (FEA), a theoretical study was carried out on the influence of elastic properties of plastics, used in the achieving of lumbar orthoses, on the state of tension and on the local displacements of the bone fragments from the traumatized area under the condition of the movement from the base of extension and flexion. In the study the force of flexion, the force of extension and the elastic modulus of plastic material varied on three levels. The theoretical results obtained were completed with clinical trials carried out on a total of 26 patients who suffer thoraco-lumbar comminutive fracture, burst fractures type, at vertebra T11 and were immobilized in Boston-type plastic orthoses made of: polypropylene (PP), rigid vinyl polychloride (PVC-D) and polytetrafluoroethylene (PTFE). As a result of observations, it was found that the use of an orthesis made from rigid plastic material, although it appears higher stresses in the traumatized zone, the displacements of bone fragments are smaller, the pains is higher in the fractured zone, the angle of kyphosis (LKA) close to the normal value and a better mobility of the spine (ODI indicator).

The metal complexes and amine compounds are the most frequent categories of catalysts used in polyurethanes synthesis. Unfortunately, all auxiliary substances added to a synthesis increase the toxicological risk of final products used in a therapy. In the present study, polyether-urethane (PU) microstructures with and without catalyst were obtained. These structures were characterized by the measurement of samples’ pH, of their size and stability, were obtained and the skin irritation potential. The results show that samples with a neutral pH, PU microstructures with sizes between 120 and 165 nm and with a medium stability. It was found that the microstructures from syntheses with catalyst present increased values of skin irritation.

Water is an important element of life, while every industry in its processes uses an important amount of water. Following processes, the water is contaminated and requires water treatment technologies. Unconventional methods to wastewater treatment, in the last years, use membrane technology as one of the most reliable processes for contaminants removal. In this article, the influence of the different concentrations of polysulfone (PSf) on the polymeric membranes properties was studied. These membranes were obtained through phase inversion method and with different polymer concentrations: 23, 25, 27 and 30 wt.%. The performance of the membranes was studied by pure water flux, permeability and retention. It has been observed that by increasing the polymer concentration, the pure water flux and the permeability will decrease. Retention was determined using methylene blue, which is one of the most utilized dye from industry and it could be observed that by increasing the polymer concentration the retention degree of the pollutant also increases. In order to explain the evolution of membrane permeability at different polymer concentrations, surface hydrophilicity by contact angle method and cross-section SEM imaging were used.

Since the time of their introduction into medical practice, biomesh were criticized for their lack of tissue integration and the rejection due to the organism reaction for an element that is not autologous. The mechanisms by which these changes of contact between the tissue and the foreign material were produced were initially incompletely understood, but over time the involvement of the immune system mediated by the cellular or humoral local inflammatory reaction was established.