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This paper proposes to investigate in detail the behavior of polymeric membranes ultrafiltration process uses in the retention of humic acid from aqueous systems. Nowadays, the aqueous systems (contaminated water and/or wastewater) resulting from various domestic and industrial activities contain many contaminants, some of them increasingly dangerous to the environment. Laboratory testing of membranes in the ultrafiltration process as well as their experimentation with different chemical compounds is essential because it is important to know how they can be eliminated before they cause a negative impact. Testing of polymeric membranes consists in carrying out the process of ultrafiltration of aqueous systems containing humic acid over a set time, following the variation in time of the volume of permeate obtained as well as the influence of process parameters. Following the investigation of the ultrafiltration process of the water through the polymeric membrane, it was found that the formation of the humic acid layer on the surface of the membrane that favors fouling is delayed, after many hours of operation, due to both the internal fiber structure which offers advantages to this type of membranes as well as high efficiency of humic acid retention. Experimental results showed that the humic acid retention rate increased by up to 37% as a result of the double decrease of the conductivity value in the permeate samples from about 600 mS/cm to 373 mS/cm and the temperature being continuously increasing, from 22.5 at 25oC over 5 h influenced the entire ultrafiltration process. The full process approach as well as the expression and interpretation of the results will be detailed in this paper.

The large diversity of clinical forms in Angle second class malocclusion explains the interest of researchers and clinicians in identifying changes in the dental arch in subdivisions II/1 and II/2. The purpose of the study is to identify the characteristics of the dental alveolar arch in order to determine the differences between class II/l and II/2 malocclusions. The study was conducted on dental gypsum models of 62 orthodontic untreated patients diagnosed with class II/1 Angle malocclusion, respectively class II/2. The results obtained by us reveals a statistically significant differentiation in the dental arcade, a narrowed maxillary arch at the molar level and elongated at premolar and molar level, in subdivision II/l. Our data are consistent with the results of literature. The knowledge of dental arch features serves to develop a correct and complete diagnosis and also to reach the therapeutic goals and to evaluate post-treatment response in short, medium and long term.

The use of collagen scaffolds and stem cells for obtaining a tissue-engineering complex has been an important concept in promoting repair and regeneration of the bone tissue. Such units represent important steps in the development of an ideal scaffold-cell complex that would sustain new bone apposition. The aim of our study was to perform a histologic evaluation of the healing of critical-sized bone defects, using a biologic collagen scaffold with adipose-derived mesenchymal stem cells, in comparison to negative controls created in the adjacent bone. We used 16 Wistar rats and according to the study design 2 calvarial bone defects were created in each animal, one was filled with collagen seeded with adipose-derived stem cells and the other one was considered negative control. During the following month, at weekly intervals, the animals were euthanized and the specimens from bone defects were histologically evaluated. The results showed that these scaffolds were highly biocompatible as only moderate inflammation no rejection reactions were observed. Furthermore, the first signs of osseous healing appeared after two weeks accompanied by angiogenesis. Collagen scaffolds seeded with adipose-derived mesenchymal stem cells can be considered a promising treatment option in bone regeneration of large defects.

The drug carriers represent a very important and modern pathway used to increase the therapeutic efficacy of the natural active substances. Nano-sized assemblies of noble metals and herbal extracts represent very simple, cheap, biologically and ecologically friendly synthesis. The main aims of this study were to obtain polyurethane nanovesicles containing silver nanoparticles and to evaluate their release rate. The vesicles’ sizes, homogeneity and surface charge were studied using a Cordouan Technol. Zetasizer, while the thermal behaviour was assessed by DSC. UV-Vis measurements were done to evaluate the release rate. Toxicological effects were studied by non-invasive techniques on human skin. The results suggest the obtaining of homogenous polyurethane nanovesicles between 80 and 95 nm, with positive surface charge, very good thermal stability and a prolonged release. The non-irritation potential recommends these vesicles as a safe carrier for different herbal extracts.

Sewage sludge resulted from urban wastewater treatment plants is generally accepted as a valuable source of nutrient and soil conditioner for agricultural usage. Analysis of amount of heavy metals in sewage sludge is essential previous to utilization of the sludge to agriculture considering the inevitable risk of heavy metal toxicity to soil, vegetation and humans. The present paper aims to analyse the characteristics of the sewage sludge resulted in an urban area for 5 years. Sewage sludge generated from five wastewater treatment plants in the South and South Est part of Romania were analysed.

In total edentulous treatment can be used a variety of means capable to reconstruct through artificial prosthetic devices the edentulous dental arches, in an individualized manner depending on the clinical situation, objectives and criteria for treatment. The present study was intended to evaluate the effectiveness of general treatment with vitamin B12 and the effectiveness of local treatment, achieved through complete dentures and to emphasize the much easier and cheaper way to do the same treatment over the same time period.

The purpose of this experimental study is to present the design and biomechanical characteristics of cemented total knee prostheses type rotating-hinge RT-PLUS® (Smith&Nephew), as well as to evaluate their use in severe haemophilic knee arthropathy with major bone damage, ligamentous lesions, axial deviations and muscle retractions. We retrospectively evaluated 5 patients with severe haemophilic arthropathy with an average age of 48.5years. The functional results are good, with a significant improvement of range of motion (ROM) and pain relief resulting in a much better life quality. We did not have any stem loosening or any other complications except 2 wound healing problems which were treated successfully. The authors recommend this type of arthroplasty in severe haemophilic knee arthropathy or in any primary knee osteoarthritis with severe bone loss or any kind of ligamentous lesions.

Importance and use of composite materials are no longer a subject that should be emphasized. They offer a successful replacement for classical materials in most areas of engineering, conferring similar elastic-mechanical properties to metal or non-metal alloys with several advantages such as reduced mass, chemical resistance etc. Considering this, knowledge of the elastic-mechanical characteristics is of utmost importance. The present article aims to create a finite element model that can predict the longitudinal elastic modulus of a double-layered composite material based on the elastic characteristics of its constituents. For this, the elastic characteristics of the constituents were determined, then used in the finite element analysis thus obtaining the Young’s modulus for the numerical composite material. Also, the longitudinal elastic modulus of the resultant composite was determined experimentally. The results of the finite element model were compared with experimental values.

In this research are establish the technology of 3D printable parts by the principle of FDM 3D printed for threaded made by PLA, ABS, Nylon or PETG. In the paper are present first the dimensional generation and specific aspects that need to be considered to produce threaded with internal teeth of the metric, round or trapezoidal type. Generating the threaded appeared as a necessity for the reconditioning or made of the components of the processing machines made both in the process of elaboration of the bachelor’s and the laboratory works, with reduced energy resource consumption and low pollution as low as possible. After the construction, it is identify the dimension that have implications for both mechanical and kinematic resistance to make a product with good cinematic and functional characteristics. After that are made an analysis of the layers generated, both from the computer simulation and from the point of view of the analysis of layers physically generated for a threaded with internal teeth. At the end are presented which are necessary for operations to obtain a product with good features starting from two types of thread generated 8x2 and 10x2 moments.

Turmeric, with its active component curcumin has been regarded lately as an important potential therapeutic agent due to its properties and many uses. Further research needs to be done both on animals and humans in order for it to be used at a large scale. As curcumin gets absorbed better through topical and not oral administration, curcumin-based pharmaceuticals with skin passage must be devised. In order for this to be done, the need for a standardized, verified and simple extraction method and one for ointment preparation with stability in time rises. We propose in this study a method for curcumin extraction, one that ensures an adequate stability in time and a method for pharmaceutical control.