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Nanoparticles: Hope for the agriculture of the future

nasa.univerzita@uniba.sk — Thu, 09 May 2024 12:36:00 +0200

How can you describe a nanoparticle? A nanoparticle can only be seen under an electron microscope, nanoparticles measure from 1 to 100 nanometres. For comparison, the diameter of a hair is 40 to 100 micrometres and 1 micrometre is 1000 nanometres. So the diameter of a hair is equivalent to between 40,000 and 100,000 nanoparticles. What is it like to work with something that small in the lab? How do you research them? We work with very large numbers and observe them as white or coloured powder, which is actually just a big bunch of nanoparticles. When we "dissolve" them in water, they form a very fine, cloudy mixture of some colour, depending on what substance they contain. I really enjoy showing our students nanoparticles of gold. They measure about 14 nanometres and their suspension looks like a ferociously purple soft drink. But we all know that gold is yellow. That is precisely what happens on nano-scale. Nanoparticles are very tiny and exhibit special quantum effects, which means they produce a different colour than micro- or macro- particles. This comes from physics that I personally do not research, just make use of. We can measure how many nanoparticles there are in, say, a litre of solution. It is similar to dissolving soluble chemicals, except nanoparticles are not really soluble at all. They are just so small and have such a large surface charge that they repel each other. Because of this property, they can pretend to dissolve, i.e. become suspended. In your research, you study the concentration of nanoparticles in the soil, determining when their concentration becomes harmful and when it has positive effects on the soil. How did you get there? During my master study, I researched how the pharmaceutical substance ibuprofen binds to soil. It gets there, for example, from sewage sludge. Ibuprofen is a small, simple molecule, so it is usually very easily consumed by microorganisms as a source of carbon. I came across studies on nanoparticles of ibuprofen that can increase its effectiveness in the human body. And since I was already working with soil samples, I began focusing on inorganic nanoparticles in soil during my doctoral studies. You research man-made inorganic nanoparticles. What kind are they? I mostly focus on zinc, or more exactly, zinc oxide nanoparticles. Zinc is one of the important micronutrients for plants. It is essential as a coenzyme in more than 200 enzymes, to maintain correct chemical reactions in the body. However, plants suffer from a lack of zinc in areas with strong soil weathering, i.e. in the tropical and subtropical zones. Zinc oxide is quickly leached from the soil. Can that be prevented? That is precisely our focus right now. We investigate how zinc oxide nanoparticles of different sizes behave in soil. We discovered that it is more effective to add zinc to the surface of the leaves than to add it into the soil. Nanoparticles remain on the leaf surface and form a kind of film. They quickly reach the parts of the leaf that are important for photosynthesis. At the same time, they slightly absorb or reflect UVA and UVB radiation. In this way they protect photosynthetic pigments such as chlorophyll. This increases the lifespan of the pigments and prevents them from degrading as quickly in sunlight. The effect is similar to that of sunscreen on the skin. There, you also create a film of mineral sunscreen that reflects UVA and UVB radiation. Nanoparticles can be transparent, but they still capture UVA and UVB rays. Does that mean that spraying zinc compounds on plants in the form of nanoparticles could have a great effect on the overall prosperity of the plant? Yes, and it could significantly help agriculture in dry and hot climates. Given overall climate developments, this is starting to be a problem in our country as well.

Mgr. Martin Šebesta, PhD.,

studied environmental geochemistry and environmental science at the Faculty of Natural Sciences (FNS) of Comenius University Bratislava. At present he works at the Institute of Laboratory Research of Geomaterials, FNS. He studies the interaction of man-made inorganic nanoparticles with soils, plants and microscopic filamentous fungi, as well as the application of these nanoparticles to plants, and in the cleaning of contaminated water, soil and sediments. He is the coordinator of the FNS Community Garden project which includes an eligible course during which he and the students are applying the principles of permaculture to the cultivation of plants at the faculty. He received the Slovak 2023 Personality in science and technology under 35 prize.

In your VEGA project, you also study inorganic nanoparticles and fungi. How are they related? We are studying how to "wrap" a nanoparticle of, for example, zinc oxide so that as much zinc as possible reaches the plant exactly where it is needed. Wood-decay fungi like the oyster mushroom are special in that they want to penetrate the tissues of the plant, and have specific enzymes to do that. These enzymes could also help the nanoparticle get into the plant better. In other words, we want to use the properties of mushrooms and moulds that we usually don't particularly like, for something useful. We synthesize nanoparticles in the presence of organic substances secreted by the fungi, and we investigate how they are transported to the inner tissues, where in the plant they accumulate, and so on. Where do you source the mushrooms for your research? My doctoral student Veronika Cyprichová has a mushroom farm run by the non-profit organization Drž hubu (Literal Slovak translation: 'Hold the Mushroom’, and also ‘Shut Up!’). Only the fruit body of the mushroom can be sold for consumption, but the most vital part – the mycelium that spreads through the soil or dying tree trunks – is usually thrown away and composted. However, this is the part of the fungus from which we can obtain various enzymes and proteins by extracting them into a solution. And that is the ‘wrapper’ for our nanoparticles. The coated nanoparticles could theoretically have similar or even better properties than uncoated ones. It is also a very "green" procedure, because we use the natural properties of mushrooms and work with something that would otherwise be discarded as waste. So the plant fertilizer of the future could be a combination of zinc nanoparticles and their coating, made of proteins from organic matter that would otherwise end up as waste, applied by spraying on leaves. Yes. I believe that the ultimate goal of this research is to produce commercially viable nanoparticles with a coating that is well absorbed and utilised by the plant. Where will your research lead you next? In the following years, I will synthesize other metals: in addition to zinc oxide nanoparticles we also want to work with iron, because iron is another important element for living organisms. But I also work with gold. Of course, gold nanoparticles will not be applied commercially to plants because even if they had any positive effect, the cost would be too great. But gold is a very good subject for analysis, because it is easy to work with. We can easily see whether its nanoparticles penetrated into certain parts of the leaves or stem. At the same time, we know that all the gold we measure in the plant is the gold that we applied to it and the plant did not obtain it from other sources like soil. With zinc, this is impossible to guarantee, because the plant must have already contained a certain amount of zinc before the experiment, or else it would not have grown at all. You have received the Slovak 2023 Personality in science and technology under 35 prize. The award was presented to you at the gala dinner which was the culmination of the Week of Science and Technology. What does that mean for you? In a way, it was very pleasant. The only stressful thing was that this was my first time speaking on live TV. I think I can give a lecture, I can be quite confident in front of the class, but with three spotlights in my face on stage, it was much more difficult. I did have a prepared speech, but the moment I walked on the stage, I forgot all of it. In addition to lecturing at the faculty, you are also an avid populariser of science. I was a lecturer for the non-profit environmental organization Daphne, which educates students about environmental protection. I gave lectures at primary and secondary schools and gave tours to groups of children of places of exceptional natural interest or preserved natural areas around Bratislava – Dunajské luhy or Devínska kobyla, which supports enormous biodiversity, many rare species and unusual habitats. Through Daphne, as a college student, I went to the U.S. for 10 months, to one of the most popular national parks, the Cuyahoga Valley National Park in Ohio. In the environmental education center there, I lectured to primary and secondary school children about the environment. I'm still learning to talk about my own research in an intelligible way, and I realise it is very important. How does the Faculty of Natural Sciences support your research? Our laboratory was renovated using ACCORD project funding, we now have better equipment and the overall work environment was greatly improved. We also have a good cooperation with the Slovak Academy of Sciences, who can do analyses for us which we are unable to do with our equipment. I also have great team-mates, and the head of our Institute for Laboratory Research of Geomaterials, associate professor Peter Matúš, gives me sufficient freedom in research. Barbora Tancerová

Visiting from The University of Texas at Arlington

Wed, 24 Apr 2024 08:43:00 +0200

Prof. Schug visited our faculty as part of his Fulbright program at the invitation of Dr. Katarína Maráková. The three-day visit strengthened mutual ongoing cooperation, established new contacts, and opened the possibility of further collaboration on new projects. We also plan to prepare a bilateral agreement between our institutions to support the student exchange program, which will increase the internationalisation of our faculty. We believe last week's visit began a more extensive and long-term cooperation, mutual inspiration, and sharing of ideas to move us forward.

CURRENT TRENDS IN THE REGULATION OF INVESTMENT INNOVATION AT THE ALUMNI CLUB OF FLAW CU

Thu, 25 Apr 2024 14:46:00 +0200

On Monday 15 April, a panel discussion organised by the Alumni Club of FLAW CU on the topic "Trends in the regulation of investment innovations, with particular emphasis on crypto assets, crowdfunding, other innovations and regulatory challenges and risks" was held at the Faculty of Law of Comenius University in Bratislava. The Alumni Club FLAW CU invited prominent experts from the field of law, finance, and business to present their knowledge and views on the current state and future of regulation of new investment instruments. PRESS RELEASE TU

Mobile phones are full of life, and we should disinfect them

nasa.univerzita@uniba.sk — Thu, 09 May 2024 12:52:00 +0200

Adrián and Marek began researching the "life” on the surface of smartphones as part of the Student Research Activity (ŠVOČ) in their third year of general medicine studies. The idea was born during an exercise in microbiology. They realized that students carry mobile phones all the time, even during hospital practice, where they use them to jot down notes about patients while reviewing their medical history, to find out the effect and composition of medicines in internet databases, or to compare laboratory results. However, some of the bacteria in the hospital can be a source of nosocomial infections. "We thought it would be interesting to look at the mobile phones of young medics to see if they “took” some dangerous bacteria with them when they left the hospital - even those that might be resistant to antibiotics. The reverse situation was also considered: could they carry pathogens on their mobile phones that might potentially be a threat to hospital patients," explains Adrián Binka. Samples from displays In their research they chose groups of students who changed their clothes in the changing rooms after their hospital practice. The students were not informed beforehand that their mobile phones would be subject to research. Samples were taken under aseptic conditions, using disinfected gloves and while wearing a respirator, using a sterile swab moistened with a sterile physiological solution. "We smeared the screens horizontally, then vertically and crosswise, and placed the swab in transport medium to preserve the viability of the bacteria. Immediately after sampling we hurried to the Institute of Microbiology at the Faculty of Medicine and the Bratislava University Hospital where the samples were placed on blood agar. On the second and third day, we measured how much growth there was and what kinds of bacteria were present. We also sent the students a short questionnaire in which we asked them where they lived - in a student dorm or a private residence, how they travelled to school, where they usually carried their mobile phone, whether they used a disinfectant and so on," Adrián Binka describes the procedure. In total, 45 mobile phones of medics were swabbed. Specialists at the Institute of Biochemistry and Microbiology of the Slovak University of Technology helped the young researchers identify the strains of bacteria present in the samples using a mass spectrometer. Up to seven different strains The results showed that there really is a variety of things living on smartphones, up to 7 different strains of bacteria and as many as 95 colonies. The most represented types of bacteria were coagulase-negative staphylococci (51%), micrococci (21%), Moraxellaceae (8%), Bacillaceae (6%). These were mostly common bacteria that are found on the skin or in the environment. A truly dangerous bacterium was identified in only one sample. "It was Acinetobacter baumannii, which belongs to the group of the ESKAPE nosocomial bacteria, in which resistance to several antibiotic drugs is increasing. It is a bit scary. Fortunately, the strain tested by us did not show resistance to any of the antibiotics tested and based on that we assume that it was probably not a hospital isolate. The presence of this bacterium proves that transmission on a smartphone to/from the hospital is possible, because A. baumannii can survive on dry surfaces," explains Adrián. Statistical tests revealed a significant difference in the abundance of species on the displays of men and women - men’s phones had a greater variety. More strains of bacteria were discovered on the smartphones of students living in a dormitory and of students carrying their phone in the pocket than of students living elsewhere and of students carrying their phone in a backpack. Disinfecting helps What to do about it? Disinfect your mobile phone using a suitable disinfectant. "On average, 14 strains of bacteria were discovered on the smartphones whose owners don't tend to disinfect them, while we only discovered two strains on those that were regularly disinfected. Regular disinfection of the smartphone proved to be one of the factors that reduced the total number of discovered bacteria," says Adrián. The students would like to use the results of their research to improve the standard sanitization procedures that are taught during medicine study. "We proved that smartphones do carry bacteria. Fortunately, most of them are common strains that shouldn't cause any issues, but they still can survive on surfaces and can potentially present a danger to patients. Our work could lead to a change in standard procedures for medics and health professionals. Today, the standard is to disinfect hands, and 98% of our respondents confirmed that they were doing this. In the future, cell phone disinfection procedures should also be included in standard sanitization procedures," explains Adrián. Adrián and Marek published their research and successfully presented it at ŠVOČ and at a congress of young microbiologists in Brno. If they receive grant funding, they want to continue their research by testing whether antibacterial surfaces that manufacturers advertise for some mobile phones actually work. Barbora Tancerová

Seminar on Qualitative Theory of Differential Equations - Jaroslav Jaroš (25.4.2024)

Pavol.Quittner@fmph.uniba.sk — Mon, 22 Apr 2024 11:09:00 +0200

Jaroslav Jaroš:
Comparison techniques for detection of nonoscillation in half-linear differential equations of the second order More information

Seminar of Graph Theory - David Wilsch (25.4.2024)

Martin.Skoviera@fmph.uniba.sk — Mon, 22 Apr 2024 10:59:00 +0200

David Wilsch:
Hoffman-Singleton graph and ovals in the projective plane of order 5 Abstract:
The Hoffman-Singleton graph is the unique Moore graph with degree 7 and diameter 2. There is a long-standing open problem surrounding this graph. Can 7 of its copies be packed into the complete graph K_{50} such that they are edge-disjoint? In 2003, Šiagiová and Meszka used methods from topological graph theory to construct a set of five edge-disjoint copies of the Hoffman-Singleton graph in $K_{50}$ which share a common group of automorphisms of order 25. We completely classify all possible edge-disjoint quintuples of Hoffman-Singleton graphs that share such an automorphism group and show their correspondence to special sets of ovals in projective plane of order 5. We also search for similar sets of ovals in projective planes of higher orders. More information

Sustainability pervades every aspect of our lives

pr@uniba.sk — Thu, 09 May 2024 11:54:00 +0200

The FNS Sustainability association was founded a year ago at the Faculty of Natural Sciences of Comenius University. What were your expectations of this project? We are a very small and recent association. In that one year of existence we only organised a few events. Our membership is growing, some are coming, some are leaving, but we have a core of permanent members whose participation I value very much. I don't know how other student associations operate but I'm not against this kind of turnover. Associations are a great tool for like-minded students to meet and achieve their shared goals. Ours is open to anyone who cares about the environment, is active and wants to learn something new. We hold interesting events, create and strengthen friendships across the faculty and try to operate sustainably. Why was you association created? Did the teachers support you? The former vice-dean of FNS Peter Hanajík told me about a project of the ENLIGHT alliance, which includes schools from several countries in Europe and also focuses on sustainability. He gave us the impetus to organise a large meeting of students at the faculty, where we talked about what we could do, but we lacked an organization that would support us. Some people naturally came to the forefront and others gradually joined in. At the next meeting, we planned the first event of the newly formed association and held it in CU’s Botanical Garden under the title 'The Naturalists’ Breakfast'. We sourced vegan food and focused on local or homemade products. The participants could sample Hungarian smoked vegan sausages and 100% plant-based sub sandwiches, which were supplied by the sponsors. The students themselves also contributed to the refreshments. Some of them brought homemade cakes or jams, and others presented their creations. Former ecology student Maroš Ondrejka presented his book “The Records of the Little Carpathians”, which took him three years of hard work to complete. One of the attendees was Atilla Balogh who studiers effective learning. How was this first event received? The Naturalists’ Breakfast was a success, and that was very nice. It happened right after the pandemic when we were still not used to meeting in person. They say that love goes through the stomach and so do good times, which is why we in the association had the idea of spending some time together while eating. We invited students and teachers and received a lot of praise afterwards. The association formed new friendships and those involved had an excellent opportunity to learn how to organise an event and get things done at the faculty. Half a year later you organised another event. Yes, it was a swap that we originally wanted to do before the breakfast, but we overreached and it only materialised a few months later. First we needed to become a true team with a common goal. In this case, we invited the students to give a second chance to the clothes they no longer wore, but that could make someone else happy. The call produced enough clothes to fill three mobile racks. Every ‘shopper’ could sweeten their deal with sustainable snacks. We got vegan cinnamon and pistachio pastries. In the end, the swap was quite successful and we got a lot of positive feedback. It motivated us to continue organising such swaps. You also held a benefit event, right? Tell us more… Our members Lucka and Naty came up with the idea of baking Christmas pastries which were offered in exchange for a voluntary contribution. The entire proceeds would be given to a charity. The event took place just before the holidays when there weren't many people in the school, but we still managed to collect about 150 euros. We donated the money to the Sant'Egidio Slovakia project - "Give Christmas to people without a home". You recently held another swap, with a lecture. Is clothes swapping becoming a theme for you? It is a very popular format and we would like to continue doing it. We think it would be great to have a permanent swap at school. There could be a permanent rack or a designated place where students could leave their used clothes. Of course, someone would have to make sure the rack is not overfilling, and excess items could be taken for further processing or to people who really need them. This idea has not been worked out completely and we are still thinking about its implementation. I hope that in the next academic year, when I return to Slovakia, we can finally launch it. Who did you invite to the April swap? The grant that we received for the association's operation allowed us to add an interesting workshop. We invited La Florita, a slow fashion blogger and upcycling teacher, who accepted our invitation. At an interactive lecture, she taught how to distinguish high-quality from low-quality materials and brought samples that participants could touch and see with their own eyes. I did not attend the lecture, but reviews indicate it was quite a success. Are you planning any other activities before the end of the academic year? I personally enjoy networking, connecting with people and spreading the ideas of sustainability. So I would definitely like the portfolio of events to grow in some way. In the near future, we are planning a farewell breakfast for naturalists at the end of the summer semester, and we might also invite some guests. We will let you know through our social networks who they will be. Eva Kopecká

New Ph.D. Programme: “Law and Digital Technologies“ at UPOL Law Faculty

Fri, 19 Apr 2024 11:47:00 +0200

We are excited to announce the launch of a new doctoral study programme Law and Digital Technologies at our Faculty of Law starting in the upcoming academic year. This interdisciplinary study programme is focused on the complex interactions between law and digital technologies and is implemented in cooperation with the Faculty of Science, specifically the Department of Informatics.

For those interested we prepared a Q&A session that will take place on 7th May 2024 at 10.00 CET. The ZOOM meeting registration link is here.

Nuclear Seminar - Ivan Kontuľ (24.4.2024)

Jaroslav.Stanicek@fmph.uniba.sk — Thu, 18 Apr 2024 10:11:00 +0200

Mgr. Ivan Kontuľ, PhD.:
Radiocarbon dating and bayesian chronological analysis

Abstract:
Radiocarbon analysis is often used for the purpose of age determination of samples from archaeological finds or environmental records. When dealing with larger data sets for one location, it is possible to use bayesian chronological analysis for chronological modelling of these locations. This method allows us to combine age determination with historical or archaeological information in order to deepen the understanding of the chronology of the studied site. At this seminar the possible uses of bayesian chronological analysis will be presented, as well as results from dating of the Church of Saint Margaret of Antioch in Kopčany obtained by this method.

A STUDENT FROM THE FACULTY OF LAW CU BECOMES PRIME MINISTER

Thu, 18 Apr 2024 10:15:00 +0200

Six Slovak students participated in a simulation of the Council of the European Union negotiations (#ConSIMium). The competition was organised by the General Secretariat of the Council of the European Union. In Slovakia, the project partner was the Slovak Rectors' Conference. The Slovak delegation was successfully represented by Sofia Šillerová from the Faculty of Law of Comenius University in Bratislava, who held the position of Prime Minister and led the delegation. On 8 and 9 April 2024, student delegates and national coordinators from EU Member States had the opportunity to experience the negotiations of Prime Ministers, ambassadors, ministers and experts at first hand or to try the role of journalists at the Council of the EU. The simulation sessions focused on digital transition, artificial intelligence, and cybersecurity. Sofia said of her experience as Prime Minister: "My task was to network with the other leaders of the Member States right from the start and then to copy the actions of the leaders at the real summits. First, we had the opportunity to provide a doorstep where we expressed Slovakia's position and main objectives in the areas discussed. We then moved on to the summit, where together with other Member States' leaders we identified the main boundaries of the new EU AI and Cybersecurity Act. The following day, during Coreper, an urgent message came and a special leaders' summit had to be convened, for which we had just over 2 hours to prepare. This last experience, and the efforts of the organising team to deepen our experience of the simulation even more, was in my opinion the most beneficial. None of us expected such a situation and we had to quickly prepare our position with our great Slovak delegation and then take the time to find partners who will share our position at the Summit."