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Dragoslav Stamenković and Kosovka Obradović Đuričić

Open access

Dijana Trišić, Vukoman Jokanović, Đorđe Antonijević and Dejan Marković

Summary

Stem cells have shown great potential for in vitro tissue engineering, regenerative medicine, cell therapy and pharmaceutical applications. All these applications, especially in clinical trials, will require guided production of high-quality cells. Traditional culture techniques and applications have been performed for the majority of primary and established cell lines and standardized for various analyses. Still, these culture conditions are unable to mimic dynamic and specialized three-dimensional microenvironment of the stem cells’ niche from in vivo conditions. In an attempt to provide biomimetic microenvironments for stem cells in vitro growth, three-dimensional culture techniques have been developed. In our study advantages of newly developed porous scaffolds as the most promising in vitro imitation of niche that provides physical support, enables cell growth, regeneration and neovascularization, while they are replaced in time with newly created tissue was explained. Furthermore, dynamic cultivation techniques have been described, as new way of cell culturing that will be the main subject of our future research. In that manner, by developing an optimal dynamic culturing method, high-quality new cells and tissues would be possible to obtain, for any future clinical application.

Open access

Magdalena Kachel, Arkadiusz Matwijczuk, Artur Przywara, Artur Kraszkiewicz and Milan Koszel

Abstract

Biodiesel has become more attractive material for its properties such as biodegradability, renewability and very low toxicity of its combustion products. A higher quality of this fuel is essential in its potential commercialization. Analytical methods used in biodiesel analysis are constantly refined. The most popular analytical techniques include chromatography and molecular spectroscopy. The ATR-FTIR spectroscopy is one of the most important methods of spectroscopy. This paper presents the results of studies on selected oils of natural origin using ATR-FTIR infrared absorption spectroscopy. Three types of oils from pumpkin seeds and winter rapeseed were analysed. The main fatty acids were also determined in all the samples.

Open access

Arkadiusz Dyjakon, Jan den Boer, Daniel García-Galindo, Florian Adamczyk, Eva Lopez, Fernando Sebastian, Allesandro Suardi, Girma Gebresenbet, Raida Jirjis, Techane Bosona, Sonja Germer and Wolf-Anno Bischoff

Abstract

To determine the environmental impact, the assessment of the Euro-Pruning project strategy has been carried out in accordance with the checking and scooping list related to Directive 97/11/EC. Additionally, some suggestions and recommendations to prevent/minimize the hazard of accidents or negative interaction on surrounding have been elaborated (according to the suggested procedure in ISO 14001 methodology: risk definition and prevention action proposal). As a consequence, the results of the inspection during the demo tests taking place in different orchards/plantations regarding the performance of the machineries operation, farmers’ habits and pruning residues harvesting procedures have been presented, in order to diagnose and determine possible risks that may occur and influence negatively the local environment. Similar activities have been carried out during the storage tests and transportation processes.

Open access

Arkadiusz Dyjakon, Jan den Boer and Daniel García-Galindo

Abstract

The energy potential from pruning residues of permanent crops is significant. However, there is not much data about the environmental influence of the processes related to harvesting, storage and transportation of pruning residues. In this paper, the methodology of analysis of the environmental impact assessment applied within the EuroPruning project is presented. The screening and scoping steps in accordance with Directive 97/11/EC as well as other procedures included in ISO 14001 methodology, which are related to the environmental impact, are described. As a result, the selected approach for the determination of the potential environmental effects, including risk description and prevention actions is presented.

Open access

Irena Kuzmanović Radman, Adriana Arbutina, Renata Josipović and Aleksandra Đeri

Summary

Introduction Currently, one of the most important ecological issues is exposure to lead in environment, since it is a metal with evident toxic effects on human organism. Hard dental tissues are suitable structures for assessing long-term effects of exposure to toxic metals. The aim of this paper was to determine the concentration of lead in hard dental tissues of a rat with experimentally induced DM using SEM/EDS analysis, after 14 and 30 days of exposing animals to lead. Material and methods The study was conducted in rats of Wistar strains divided into the three groups. The first group consisted of 8 rats (128 molars and premolars of the upper and lower jaws) with experimentally induced DM, taking lead in the course of 14 days at the concentration of 1500 ppm; the second group included 8 rats (128 molars and premolars of the upper and lower jaws) taking lead in the course of 30 days at the concentration of 1500 ppm, while the third control group consisted of 5 healthy rats (80 molars and premolars of the upper and lower jaws). Experimental animals received lead-acetate every day at the concentration of 1500 ppm via water ad libitum. In these animals, diabetes mellitus was induced by Alloxan. The teeth samples were analysed using scanning electron microscopy (SEM). EDS analysis determined the mass fraction of lead and other elements in hard dental tissues. Results No lead was detected in a single tooth layer in the teeth of rats that received lead in drinking water in the course of 14 days. The average values of the mass fraction of lead, calcium, and phosphorus in enamel of teeth of rats receiving lead in the course of 30 days amounted to: lead 0.36%, calcium 15.48%, and phosphorus 10.62%. Lead was registered only in enamel. Conclusion Lead was detected in enamel only in rats receiving lead in the course of 30 days while it was not detected in teeth after the course of 14 days.

Open access

Maciej Neugebauer

Abstract

The process of composting biological waste is a natural process – in which heat is released. Biological wastes generated in typical households in Poland – are mainly kitchen waste (KW) and green waste from home gardens (GGW – if they are owned). From the ecological point of view – the most advantageous method of their management is their utilization in the place of production. The paper presents a proposal for effective management of bio-waste arising by composting – with the simultaneous use of heat for greenhouse heating in autumn. This is to encourage residents to independently compost bio-waste – and increase the level of recycling of waste generated in Poland by 2020. Calculations for greenhouses were made – in accordance with the energy audit methodology. The obtained thermal balance results were compared with the actual temperature prevailing in the greenhouse in autumn. These calculations were the basis for calculating the amount of KW and GGW enabling effective heating of greenhouses in the autumn so that the internal temperature does not drop below 10ºC. It has been calculated that 22 kg of composted bio-waste (KW and GGW) will suffice to heat the greenhouse in October with an area of 18 m2.

Open access

Waclaw Romaniuk, Victor Polishchuk, Andrzej Marczuk, Liudmyla Titova, Ivan Rogovskii and Kinga Borek

Abstract

The solid fraction, according to many researches, is an effective organic fertilizer, the activity of which is at the level of mineral fertilizers and even exceeds their effectiveness, while the use of the liquid fraction does not always give positive results. In the article the optimal concentration of the liquid fraction in water solution for fertilization during cultivation of onion for chives in soil was determined. Sediment from biogas production was obtained at the thermophilic fermentation (50ºC) of cattle manure in the laboratory institution which operated at the periodical regime of loading. Fermentation lasted 25 days. Seven variants of plant feeding were assessed: clean water (control), mineral fertilizers (solution of ammonium nitrate in water in the concentration of 1:25), unsolved liquid biofuel fraction and mixture of liquid fraction from the postferment with water in concentrations of 1:10, 1:50, 1:100, 1:500. It was determined that the highest efficiency was observed in case of fertilization of plants with the mixture of liquid fraction from postferment with concentration of 1:500. Along with the increase of liquid fraction concentration and fertilization of plants with water solution of mineral fertilizers, onion productivity dropped slightly. Fertilization of plants with the liquid fraction from postferment resulted in fractional dying of plants and reduction of efficiency. The crop control of nitrogen content proved that in case of every day watering of onion with clean water and mixture of liquid fraction with water concentration of 1:100-1:500 did not exceed the maximum admissible concentration which is 800 mg·kg−1. Thus, in case of onion cultivation for chives, taking into consideration the crop growth and low nitrogen content, it is recommended to use the mixture of liquid fraction with water of 1:500 concentration.

Open access

Marek Jałbrzykowski, Katarzyna Leszczyńska, Sławomir Obidziński, Łukasz Minarowski and Magdalena Laabs

Abstract

The paper presents results of microbiological research of plastic elements. Plastic elements were made of the polystyrene composition with addition of nanosilver and nanocopper with a laboratory extruder EHP 25ELine. Microbiological research was carried with regard to evaluation of antifungal impact of nanoadditives according to international standards with Cryobank (Mast Diagnostica). A positive impact of nanoadditives on antifungal properties of polystyrene elements produced by means of extrusion which is very favourable in the aspect of their use in agri-food processing.

Open access

Marija Živković Sandić, Neda Stefanović, Branka Popović and Branislav Glišić

Summary

Tooth agenesis is common dentofacial malformation in humans. Its etiology is still not clear. Hypodontia has been regarded as a multifactorial condition influenced by gene function, environmental interaction and developmental timing. More than 300 genes have been related with patterning, morphogenesis and cell differentiation in teeth. According to data WNT10A gene is considered to have an important role in odontogonesis. The aim of this study was to show mutation status in WNT10A gene in a family with two members with diagnosis of hypodontia/oligodontia. In the reported family (father, mother, son, daughter) children were diagnosed with congenital tooth agenesis (son-2 teeth, daughter-11 teeth), while parents negated congenital absence of teeth. We identified a heterozygous missense mutation, c.682T>A (p.Phe228Ile) within the exon 3 of WNT10A in mother and father and the same homozygous mutation was detected in the same region of WNT10A gene in daughter and son. Observed differences in our study, from no symptoms to mild/severe hypodontia, could be the consequence of genetic influence of c.682T>A(p.Phe228Ile) mutation, but also the contribution of many environmental factors during odontogenesis.