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Abstract

Fly ash and slag were examined for the removal processes of Pb(II) ions from water in batch experiments under different conditions of adsorbent dosage, initial concentration, pH and contact time. The materials are industrial waste generated from the high temperature treatment of sewage sludge by the circulating fluidized bed combustion (CFBC) technology. Physical and chemical properties, as well as adsorption efficiency and calculated maximum adsorption capacity of Pb(II) ions were determined using a variety of methods. The kinetic analysis revealed that the adsorption process is better described by the pseudo-second order equation and it is well fitted to the Freundlich model.

Abstract

Zakopane is a regional tourist city that is unique on the national scale. It is a one of a kind mountain resort with an exceptional history and atmosphere. It is a fashionable place where visitors can both rest and test themselves. It currently requires not only sustainable development but also that the effects of negligence and its deficiencies in spheres required for it to comfortably function be addressed, in addition to the supplementation of its offering both in terms of use and culture. The small-scale architecture of the Podhale region must rise to contemporary challenges. Presenting underground projects from all over the world aids in raising awareness as to the development potential of the area, demonstrating one of the paths to solving the problems of overburdened cities. Examples show means of relieving the pressure of current needs, simultaneously relieving the above-ground service programme of cities and increasing the amounts of greenery at their disposal.

Abstract

This paper is an attempt at reconstructing Stanisław Witkiewicz’s creative method on the basis of his scattered writings. The Zakopane style has become a phenomenon across a broad spectrum of Polish national styles. The inspirations for classical national styles were typically arbitrarily selected sets of forms taken from a specific historical style associated with a given nation or state. It was often an eclectic set – enriched with elements derived from other styles. Stanisław Witkiewicz consistently avoided borrowing and copying, confining himself solely to drawing inspiration from the folk art of Podhale. In the methodology of his architecture, rational elements (exposing the structure, stressing hygiene) interweaved with ornamentation, predominantly featuring floral themes and elements of a specific mythology.

Abstract

Magnesium based alloys are very promising material to be used mainly for biodegradable implants in medical applications. However, due to their very low corrosion resistance in the environment of in vivo is their use limited. Increase of the corrosion resistance of magnesium alloys in vivo can be achieved, for example, by a suitable choice of surface treatment while the biocompatibility must be ensured. Fluoride conversion coatings meet these requirements. Unconventional fluoride conversion coating was prepared on ZE41 magnesium alloy by dipping the magnesium alloy into the Na[BF4] salt melt at 450 °C for 0.5; 2 and 8 h. The morphology and thickness of the prepared fluoride conversion coatings were investigated as well as the corrosion resistance of the treated and untreated ZE41 magnesium alloy specimens. The corrosion resistance of the untreated and treated ZE41 magnesium alloy was investigated using electrochemical impedance spectroscopy in the environment of the simulated body fluids at 37 ± 2 °C. The obtained results showed a positive influence of the fluoride conversion coating on the corrosion resistance of the ZE41 magnesium alloy.

Abstract

This study was conducted to identify the most deleterious nonsynonymous single nucleotide polymorphisms (nsSNPs) in the ovalbumin gene family, including OVALX, OVALY, and OVAL genes, which are involved in the synthesis of the most important components in the chickens’ eggs using a comprehensive in silico approach. Ten different computational servers were utilized to prioritize the possible deleterious effects of the retrieved nsSNPs in terms of structure, function, and stability. Results indicated entirely damaging effects of H365P in OVALX, I167T in OVALY, and V209G, L231P, F307C, and S317P in OVAL proteins. Further prediction tools showed that all of these deleterious nsSNPs were positioned in variable locations within several α-helix motifs in all studied ovalbumin proteins. Furthermore, all witnessed nsSNPs were predicted to be resided in the receptors binding sites, signifying remarkable involvement of such nsSNPs in damaging of the altered proteins. In conclusion, the present study provides the first inclusive data with regard to the most deleterious nsSNPs in OVALX, OVALY and OVAL genes in chickens. The present bioinformatics data may be useful for breeders who intend to raise chickens for egg production, in such a way the presence of any of these deleterious nsSNPs in any selected breed may possess several damaging effects on the egg components, which may impair egg production. Therefore, it can be stated that breeders have to confirm the absence of any of these deleterious nsSNPs before being proceeded further for large-scale egg-production purposes.

Abstract

Carrot is one of the most important root vegetables rich in bioactive compounds such as carotenoids and dietary fibres, with appreciable levels of several other functional components and having significant health-promoting properties. Therefore, it is cultivated on a large scale throughout the world. The by-product (pomace) resulted during carrot juice production is used mainly as animal feed although it contains many valuable components and could therefore be used profitably in the food industry, too. Carrot pomace needs to be preserved by drying as otherwise it deteriorates rapidly. In our research, we studied the infrared drying kinetics of carrot pomace at various temperatures, the obtained data being very important in the drying practice.

Abstract

Methylxanthines such as caffeine, theophylline, theobromine are significant and widespread psychoactive substances. We developed the isocratic method with optimum composition of the mobile phase 90 % water: 10 % acetonitrile and confirmed repeatability of retention times and peak areas. The developed HPLC method was applied to determine the content of methylxanthines in selected types of black and green teas available on the market. Of the black teas (tea bags), the highest concentration of theobromine was found in Ceylon tea (18.98 mg.L−1). The highest concentration of caffeine was in a cup of Earl Gray tea (254.09 mg.L−1). Among loose black teas, the highest content of both theobromine and caffeine was found in Pu Erh Superior tea, where the theobromine content was 24.62 mg.L−1 and the caffeine content was 520.67 mg.L−1. Of green powder teas, highest caffeine content (306.46 mg.L−1) was in Shizuoka Matcha Premium and the highest content of theobromine (8.45 mg.L−1) was found in GABA Midori. From the loose green tea, the highest concentration of theobromine (12.85 mg.L−1) was in Lung Ching West Lake. The highest caffeine content (484.85 mg.L−1) was in Gyokuro Shizuoka Premium Tea. In both types of teas the amount of theobromine and caffeine was quantified, but the presence of theophylline was not proven. Data on contents of these metabolites in tea products are highly informative for consumers.

Abstract

Parabens are synthetic preservatives that are used on a large scale in the cosmetics, pharmaceutical and food industries. Their task is primarily to prolong the shelf life of selected products – cosmetics, medicines or food – by maintaining their microbiological purity. Parabens protect products against deterioration and microorganisms, extending their durability by up to several months without interfering with their composition and operation. Parabens do not change the aroma, taste, density or other characteristics of cosmetic or food products. However parabens, which occur in most cosmetics with a creamy or liquid formula (face creams, body lotions, foundation, tonics, lipsticks, deodorants, perfumes), are becoming increasingly worse because of the prolonged list of side effects that they may cause. The presence of intact paraben esters in human body tissues has now been confirmed by independent measurements in human urine, and the ability of parabens to penetrate human skin intact without breakdown by esterases and to be absorbed systemically has been demonstrated through not only in vitro studies but also in vivo investigation using healthy human subjects.

Abstract

Saccharomyces boulardii (S. boulardii) has been used as a probiotic for the prevention or treatment of various human gastrointestinal diseases for many years. Thus, S. boulardii has a wide range of application prospects in medicine and food industry. The experiments were investigated with effecting of carbon sources (galactose, sucrose, fructose, maltose, lactose, glucose, and soluble starch), nitrogen sources (tryptone, casein, yeast extract, peptone, soy peptone, beef extract and malted milk; ammonium sulfate, urea, diammonium hydrogen citrate, triammonium citrate, ammonium nitrate, ammonium chloride and potassium nitrate), prebiotics (xylo-oligosaccharide, isomaltooligosaccharide, fructo-oligosaccharide, galacto-oligosaccharide, stachyose, raffinose and inulin) on the number of viable cells and dry cell weight of S. boulardii. The optimum concentration of 5 % glucose or sucrose, 2 % peptone or yeast extract, 0.4 % urea, 0.2 % fructo-oligosaccharide and 0.6 % galacto-oligosaccharide for S. boulardii grew better in medium.

Abstract

The recent years have seen a great number of instances when ultraviolet (UV) radiation was used in the preservation process of all sorts of foods. Since the purine and pyrimidine bases of DNA and RNA absorb well the 254 nm radiation, its application with the use of a correct dosage can result in disinfections of various orders of magnitude. It can be particularly effective in cases where technology does not allow a more intensive heat treatment. When used properly, UV treatment can be a competitive procedure in the case of foodstuffs where the large surface area allows for UV rays to penetrate the entire volume of the substance. Incorrectly applied UV treatment may change the composition of foods. Free-radical as well as photochemical reactions can digest the proteins, damage the antioxidants, oxidize the lipids, make changes to the colour and substance, and produce undesirable flavourings and odorous substances. Some vitamins are particularly sensitive to UV irradiation in the course of which losses could reach even 50%. Photosensitive water-soluble vitamins are vitamin C, B12, B6, B2 and folic acid, while vitamins A, K and E are the fat soluble sensitive to light, carotene being the only provitamin with such properties. On the other hand, UV treatment can be a useful tool of food safety because of the photosensitivity of fungal toxins.