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Despite many advantages, the practical application of fullerene C60 and curcumin (CUR) has been limited by their hydrophobic nature, deficient solubility in aqueous media and, therefore, poor bioavailability. In this study, aqueous nanoformulations containing C60 and CUR in the absence and presence of three solubility enhancers, β-cyclodextrin (CD), Tween 80 (T80) and polyvinylpyrrolidone (PVP), were prepared and subjected to the antioxidant activity assessment. The content of C60 and CUR, stability, size and morphology of nanoparticles were determined using UV–vis, DLS and SEM techniques. Contrary to better solubility of pure C60 than the corresponding C60-CUR system, the solubilization of CUR in hybrid suspensions was improved compared to corresponding pure CUR suspensions, with the exception of the C60-CUR-PVP formulation. The DLS results revealed nearly monodisperse nature of CUR-T80 nanoformulation, while other ones ranged from widely dispersed to polydispersed. Depending on the type of solubilizer, similarity was observed in the particle size distributions of T80- and PVP-coated nanoformulations as well as water and CD nanoformulations. The presence of T80 differently and significantly reduces the particle size in all three nanoformulations, while PVP slightly reduces CUR-based nanoparticles but increases the size of C60 nanoparticles. Zeta potential values, ranging from − 9 mV to − 34 mV, show variation in the starting stability of nanoparticles, from unstable or relatively stable three PVP formulations and C60-T80 to highly stable CUR-T80 and C60-water. Compared to water nanoformulations as a control, SEM images of dispersant-coated nanoparticles lost the visible morphology of active components, showing variation in their morphology depending on the type of dispersant and active component used. Nanoformulations containing CUR in PVP and T80 expressed a very good antioxidant potential in DPPH radical scavenging assay, much stronger than ascorbic acid. At the same time, a moderate to high antioxidant activity in β-carotene bleaching assay was reached in PVP and T80 nanoformulations containing C60, CUR, and their noncovalent hybrid, as well. Our studies have shown that T80 and PVP colloidal systems containing C60-CUR hybrid, but also their individual components, can be used as stable antioxidant nanoformulations with potential application in the field of food and pharmacology.

In Serbia, one of the former republics of Socialist Federal Republic of Yugoslavia, men and women have equal access to higher education and professional employment. However, in practice, this equality is not always realized. In this paper we describe the status of women in physics in Serbia, focusing on student gender ratios and on positions held. The financial contributions of the Serbian government to the scientific sector are not sufficient. Many young physicists enter the information technology sector, where they can earn higher salaries. In addition, the lack of career opportunities motivates scientists to go abroad, so each year, more and more young people leave Serbia. Today, many young Serbian physicists plan their departure during their studies and leave the country immediately after graduation. We present statis- tical data for the last several years, reviewing the percentage of women who are pursuing physics as a subject of study or a profession. We report gender ratios at various career stages. Teaching at the primary and high-school level is the main professional activity for female physicists in Serbia. Even though a large percentage (about 50%) of Serbian physicists are female, few women hold positions in which decisions about scientific and educational policy are made. When women achieve leadership positions, their educational attainments often outstrip those required for the positions. Only six women have a high-level management position.

The results of the effect of the growth history on Potassium Dihydrogen Phosphate (KDP) crystals growth mechanism are presented in the paper. Crystals were grown in temperature range of from aqueous solutions, saturated at . Two types of the experiments were performed. In both types, after the nucleation at crystals were grown at the same temperature for about 1.5 hour and then dissolved at temperature for about 15 min. After refaceting, in the first type, the crystal growth started at , followed by the temperature increasing in steps of to . In the second type, after refaceting the crystal growth started at , followed by the temperature decreasing in steps of to . Obtained results indicate that KDP crystals growth mechanisms do not depend on growth history. They are discussed in accordance with the current theories.