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In this study, the alkali treatment of sawdust (SD) using different concentration (1%, 3%, 5%, and 7%) of sodium hydroxide (NaOH) was performed. The phases change due to alkali treatment on sawdust particles was examined using Fourier Transform Infrared (FTIR) spectroscopy and Field Emission Scanning Electron Microscopy (FESEM). Result shows that the treatment with 5% NaOH on sawdust particles improved the surface roughness of the filler with 21.1 % diameter reduction. Both treated and untreated sawdust particles were reinforced in HDPE matrix using an extrusion method. For comparison purpose, both treated and untreated high density polyethylene/sawdust composites were tested under static and dynamic loading up to 1100 s-1 using the universal testing machine and the split Hopkinson pressure bar apparatus, respectively. Results indicate that the treated high density polyethylene/sawdust composites with better filler/matrix interlocking characteristic shows better mechanical performances as compared to untreated high density polyethylene/sawdust composites under a wide range of strain rate investigated. Apart from that, the mechanical properties of both treated and untreated polyethylene/sawdust composites also show great dependency on the strain rate applied where yield stress, compression modulus and ultimate compressive strength were steadily increased with increasing strain rate. Unfortunately, the yield strain shows the contrary trend. While for the fractographic analysis under dynamic loading, the untreated composite specimens had undergone a severe catastrophic deformation and damages than that of treated composite specimens.

The oral cavity can be considered a complex biomechanical system. Most researches about oral environment’s biomechanics, related to restorative dentistry, endodontics, orthodontics, prosthodontics and implantology are conducted in vitro. Applying the principles of engineering in dentistry contribute significantly to understand aspects of oral biomechanics. We conducted comparative research by finite element method on mixed prosthetic restorations with metal frame of CoCr and NiCr, subjected to the same experimental occlusal loading to determine what type of metal substrate has a better biomechanical behavior.When applying forces in the frontal region, the area of weakness is, according to carried out analyzes, disto-incisal angle of the lateral incisor and at the application of forces in the lateral region, the most vulnerable is disto-palatal cusp of the second molar. Overall, for the particular case analyzed, it is recommended to make metal-ceramic prosthetic restoration with metal support of CoCr, which is less distorted and strained at the experimental application of masticatory forces, compared with metal-ceramic restoration made of NiCr.

The literature highlights the use of nanoparticles for the treatment of wastewaters containing organic compounds such as hydrocarbons, phenols, etc. The oxidation process of pollutants in wastewater from catalytic cracking was performed on nanostructured catalysts based on Fe, Mn and Fe-Mn mixed. The catalysts were prepared by precipitation-coprecipitation in the presence of anti-caking. Measurements for the determination of particle size distribution were carried out using the method of dynamic light scattering. The oxidation process was conducted in a batch reactor equipped with air bubbling system, in suspension of catalysts at a concentration of 1%, a temperature of 85-90o C, pH 9.2, for a period of 2h, 4h and 6h respectively. The best results were obtained in the presence of Fe - Mn catalyst at 6 hours reaction time. Degree of contaminant removal for this catalyst had maximum values of 72.80% for COD, 77.97% for extractible, 74.4% for phenol, 67.53% for ammonium and 67.57 % for sulfides,. Better behavior of Fe - Mn catalyst in the oxidation reaction was due both to the nature of the catalyst, as to well as the smaller size of this catalyst particles.

The purpose of the study is to assess and compare the effects of different antiseptic mouthrinse solutions on traditional glass-ionomer cements. Thirty samples of three traditional glass-ionomer cements used for base: Ketac Molar Easymix (3M ESPE), for restoration: Fuji IX (GC Corporation) and for sealing: Fuji Triage (GC Corporation) were included into three groups. In group 1, the samples were immersed for 14 days, twice a day one minute each, in Listerine Cool Mint, in group 2 the samples were immersed for 14 days, twice a day one minute each, in Parodontax Extra in group 3, the samples were immersed for 14 days, twice a day one minute each, in Sensodine Cool Mint. In control group the samples were immersed in artificial saliva. Within each group, sub-groups were established according the time of cement ageing (one day,seven days and fourteen days). The samples were analyzed for surface topography using a scanning electron microscope and for chemical composition using EDX detector. The antibacterial mouthrinse solutions Listerine, Parodontax, and Sensodine have an erosive effect on traditional Fuji IX, Ketac Molar and Fuji Triage glass-ionomer cements. The most affected cement by erosive action was Ketac Molar, followed by Fuji IX and Fuji Triage. All three glass-ionomer cements tested in this study proved to be more resistant to erosive action after their ageing.

The aim of study was to evaluate some aspects in the clinical effectiveness of fibre-reinforced composite resin periodontal splints on mobile teeth. Fibres-reinforced composite resin retainers are recommended likewise in the treatment of teeth mobility. The study group was formed by a total of 62 patients, which presented first and second mobility degrees of anterior teeth (436 included teeth into research). 42 patients belonging to the experimental group with periodontal splinting, benefited by Interlig-Angelus glass-fibers and Ribbond-Seattle polyethylene-fibres reinforced composite resin splints (295 splinted teeth and 50 splints). The used composite resin was represented by Vertise™ Flow-Kerr. 20 patients (141 teeth) represented the control group, without splinting. All included patients followed periodic monitoring visits (after a week and at one month, for a period of 6 months), in order to evaluate the detaching degree/adhesive failure of reinforced composite resin splints and the reducing of dental mobility degree. The results of study revealed that between the two types of immobilization splints there was no significant difference in the degree of separation/adhesion failure, in the acceptability or in the patient s comfort. Both types of fiber-reinforced composite resin periodontal splints had beneficial effects in decreasing the degree of dental mobility and it was remarked their aesthetic acceptability, respectively the patient s comfort.

The bile duct system has one intrahepatic and as well extrahepatic distinct components, both subject to large anatomical variability. The left component of the bile duct is much more rarely when compared with than the right side. On the 100 pieces of hepatic corrosion casts, we analysed the confluence modality of II, III and IV segmental ducts, to form the lateral and medial branches, and finally the left hepatic duct. Depending on the confluence modality of these ducts and branches to form the left hepatic duct, we revealed three morphological types. In the majority of cases (Type I - 86% of cases) the confluence of segmental duct II and segmental duct III form the lateral branch and the confluence of lateral and medial branches form the left hepatic duct. In most of these cases, the confluence of segmental ducts II and III (to form the lateral branch), is located on the left side of the lateral portal branches origin branches origin, and the confluence of lateral and medial branches (to form the left hepatic duct) is located at the right of the origin of the medial portal branches. Relations of the intrahepatic biliary ducts system with the portal vein element have major practical importance in liver resection surgery and transplantation.

This research aimed to assess properties of emulsions containing various concentrations of collagen hydrolysate produced from calf skins. The most optimum variant of collagen separation from calf skins was used, developed by these authors. The resulting aqueous collagen hydrolysate was employed to produce oil/water cosmetic emulsions containing from 1 to 8 wt % of hydrolysate. Hydration and sensory properties of the proposed substances were evaluated. Appearance and rubbability of the emulsions and washability of make-up were determined. Emulsions containing collagen hydrolysates were assessed by respondents of two age brackets: 18-35 and 36-55. Stability of the emulsions was appraised using centrifuge and temperature testing. On application of these preparations, the skin was highly moistened, particularly in the older respondent group. Consistency of the emulsions was homogeneous and free from clotting. The work confirmed that part of hides constituting the waste can be a potential source of collagen used as an anti-ageing ingredient of cosmetic emulsions.

The field of cartilage repair and restoration has expanded a lot in the last decade since articular cartilage problems are very common. As a consequence, many biomaterials were created in order to aid physicians in treating different osteochondral defects. Polymers like polyurethanes or PGA-hyaluronan have been frequently used as the in vivo cartilage tissue repair solution, as reported in animal studies and in clinical applications. Three different implants (Agili-C, Hyalograft C, and Chondrotissue) were used in 23 patients (6 medial and 17 lateral lesions) in this study. Patients were assessed at 3, 6, 9, and 12 months postoperative follow-up visits using the International Knee Documentation Committee (IKDC) scores and Knee injury and Osteoarthritis Outcome Score (KOOS). The follow-up assessments demonstrated clinically and statistically significant improvements (p < 0.05) in all clinical outcome scores, as compared to the respective preoperative values: IKDC (48.9/77.1 for Chondrotissue implants), KOOS symptoms (58.2/71.9 for Agili-C implants), KOOS pain (54.8/66.1 for Agili-C implants), KOOS daily living activities (64.2/76.3 for Agili-C implants), KOOS sports (38.3/60.8 for Agili-C implants), KOOS quality of life (40.1/60.7 for Agili-C implants) demonstrating improvements in the case of implants previously mentioned. The overall results of this study support the successful use of the Agili-C, Chondrotissue and Hyalograft-C implants for the treatment of knee cartilage lesions.

Phytochemicals are biologically active chemical compounds found in plants. They were identified as displaying bioactivity in the prevention of cancer, heart disease and other diseases. The most important classes of phytochemicals are: polyphenols, carotenoids, essential oils, phytosterols etc. The encapsulation of phytochemical compounds in different matrices is required in order to prevent the degradation of phytochemical compounds under the influence of some factors such as oxygen, light radiations, pH and high temperature. Biopolymers with new functional properties, i.e. biodegradable, biocompatible and stimulus responsive, have been tested for encapsulation of phytochemicals bioactive. In this review, we are showing the most important biopolymer classes used as wall in the preparation of drug and food phytochemicals micro and nanoparticles.

A new dye-sensitized solar cell (DSSC) counter electrode was obtained through the electropolymerization of the monomer 3.4-Ethylendioxythiophene (EDOT) directly onto a indium tin oxide (ITO) coated glass in the presence of an aqueous titania nanotubes (TiO2 NTs) suspension. The TiO2 nanotubes in the anatase phase were incorporated in the conductive polymer film, being also observed an increase in the catalytic activity and the fill factor of the assembled device when using the under examination counter electrode.