The aim of experiment was to evaluate the local impact of mercury accumulations, discharge from coal power plants, by examining samples of ash, slag, soil, spontaneous vegetation and crop plants, using as analytical techniques the cold vapor atomic absorption spectroscopy. Mercury determined in samples of lignite (0.020 mg. Kg-1), is found in fly ash samples retained by filters (0.037 mg.Kg-1), bottom ash transported hydraulic in deposit (0.022 mg.Kg-1), adjacent soils landfill and the power plant (0.12 mg.Kg-1 or 0.049 mg.Kg-1). The mercury content in vegetation presents differentiated values depending on the bioavailability of plant, area and the positioning of the emission source, reaching values between 0.014 at 0.005 mg.Kg-1 in the wild flora and 0.022 mg.Kg-1 to 0.004 mg.Kg-1 for plants crop. Data obtained for plants, confirmed that most families tend to accumulate mercury plant in larger quantities in the roots (0.022 ± 0.0016 mg.Kg-1) and moderate quantities in the foliar level by translocation or by direct vapor absorption.
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Chylothorax was diagnosed in a Afghan dog 3 year old, that presented in the necropsy a accumulation of lymphatic fluid in the chest cavity. Also to examine the right heart was observed to this heartworms – Dirophylaria immitis.
The cochlear implant (C.I.) is a neurobionic prosthesis, being one of the greatest achievements of auditory neuroscience. Although C.I. represents the gold standard in the treatment of deafness in both the child and the adult, some problems like perception of speech in noise (atmosphere, environment), perception of music, binaural hearing remain, aspect to which improvements are expected. The article (this review) revises the road from the first attempts to cochlear implantation to today’s modern and reliable cochlear implant. Continuous improvement of existing technology both in terms of biomaterials used and in terms of speech processing and simultaneous stimulation strategies, promise with certainty the introduction of C.I. with superior performance. A look in the future is through new ideas and techniques, which await the transition from the experimental to the clinical stage in the emergence of a new generation of implants.
The author wants to evaluate the clinical advantages and limitations of the composite pressed on metal framework for full-arch implant-supported fixed prosthesis in comparing with dental ceramic restorations. A total of thirty-two edentulous arches were restored. All complications were recorded at each follow-up visit up to 1 year after insertion. No complications were reported on pressed composite restoration. Complications were found in the ceramic restorations like chipping or fracture of the ceramic veneer. The composite pressed restorations are a treatment option for full arch restorations over implants, showing a better success rate in the present study in comparing with ceramic restorations.
Oleogels are structured liquid oils with applications in food, cosmetic, and pharmaceutical industries. Structured oils may become alternatives to the commonly used solid fats, such as palm fat or hydrogenated fats. Properties of oleogels are primarily dependent on the structuring agent applied. This paper was intended as an examination of structuring properties and oleogel oil binding capacities of various monomer ingredients (plant and beeswaxes, monoacylglycerol) and comparison of the oleogels produced with palm fat. An oleogel produced with candelilla wax (CLX) exhibited a structure most similar to that of palm fat. These products showed statistically significant differences of colour from palm fat. In addition, textures of the oleogels differed from one another and from palm fat. Oleogel containing rice bran wax (RBX) had the most similar viscosity properties. Oleogels including candelilla wax and yellow bees wax displayed best oil binding structures (assayed by centrifugal and LumiSizer methods). When filtered (at 40°C), on the other hand, minimum oil loss after 24h was demonstrated by the oleogels containing CLX and RBX, possible evidence that these structure-forming substances roduce oleogels that could be used in products exposed to more elevated temperatures. Oleogels may become alternatives to the commonly used solid fats. Thanks to the use of oil structuring agent at the level of 3% liquid oil becomes solid. Using these innovative fat products can stabilize oil in the product, and also it can improve the nutritional value of food products by replacing a popular palm fat rich in saturated fatty acids, which exert an adverse influence on humans’ cardiovascular system, by oils rich in unsaturated fatty acids.
In this paper, optimum hot formation processing parameters for 31VMn12 steel were established, the torsion deformation of 31VMn12 steel was investigated at temperatures from 900, 1000, 11000C and strain rates from 0.05 s-1 to 3 s. –1. There were studied the structural aspects of materials, in microstructures by electronic microscopy. The stress level decreases with increasing deformation temperature and decreasing strain rate, which can be represented by a Zenner-Hollomon parameter. The mathematical model presented in the paper describes the relationship of tension strain, voltage and temperature coefficient 31VMn12 steel at high temperatures. The stress-strain curves determined by the torsion test allowed the calculation of the Zenner–Hollomon parameter corresponding to the maximum stress. By using this parameter has established a set of equations that reproduce completely stress-strain curve, including the hardening, the restoration and dynamic recrystallization area. Comparisons were made between the experimental results and the predicted and confirmed that constitutive equations developed can be used for mathematical modelling and other attempts (forging, compression) and other types of steel.
Breast reconstruction involves two major conditions: to be oncologically safe and to respect the aesthetic of the reconstructed breast. Moreover, every healthcare system in the world manifests a keen tendency to cut back on medical costs, which influences our surgical techniques and breast reconstruction procedures. The use of biological matrices like the acellular dermal matrix has become an acknowledged alternative in implant-based breast reconstruction, in spite of the many impediments and controversies that surround it. However, these matrices are costly and less attainable as compared to synthetic meshes that are conservative with resources and unyielding to the formation of biofilm bacteria. Accordingly, we decided to research the impact of synthetic meshes in implant-based breast reconstruction.
The paper presents the research carried out by our team on achieving amphiphilic polymeric microcomposites, colored in ruby and violet shades for natural fibers dyeing (cotton, wool). The colored polymeric microcomposites were characterized in term of their morpholo- gical (by optical microscopy and SEM analysis) and physicochemical performancies (by FT-IR and UV-Vis spectroscopy, colorimetric analysis). The colored microcapsules were tested by studying the controlled release of the encapsulated dyes in water, to pH variation. This study was necessary to the coloristic characterization of colored polymeric microcomposites to determine the optimal microcapsules dye concentration and dyeing concentration of natural fibers.
In the paper it is presented a new Euler – Bernoulli theory based on an assymetrical distribution of strains towards the median plane, the area subjected to compression has a transversal stretching, while the area subjected to tensile has a transversal contraction. This theory takes into account the transversal contraction factors and consequently the eigenpulsations of bars vibrations with rectangular section depend on the ratio between the bars width and thickness. This theory is experimentally verified for Dammar based composite bars reinforced with cotton, flax, silk and hemp fibers. For the considered bars, we have experimentally determined the eigen frequencies and the damping factor values.
The selective collection of plastic, paper, glass and metal waste represents a desirable behavior in any civilized community with environmental concerns. The collection and recovery of recyclable materials is also a concern for the city of Arad, the purpose of this study being that of identifying the strengths and weaknesses of selective waste collection at the level of this urban community. Starting from the premise that responsible behavior in terms of waste and its collection is an important factor in the ecological development of a community, the present article aims to explore the local realities in this regard, to diagnose the state of things, as it is at present, in the city of Arad. We have highlighted and recorded the population’s existing mentalities and perceptions, the citizens’ expectations from the local authorities, in order to provide optimal intervention opportunities to increase control for a better management of selective collection.