In vitro Formation of Isoprene Derivatives in Conditions Simulating Membranes of Plants under Heat Stress

Purpose of the Study: In plants exposed to high heat and light, excess excitation energy and radical formation generate reactive species that threaten to disrupt cellular functioning. Isoprene and nitric oxide (NO) are both produced during high heat and light intensities and confer heat tolerance via a variety of mechanisms. The reaction of isoprene with NO oxidation products to form nitro-isoprenoids (NO2-IPs) is expected to occur in the O2-rich environment of plant leaves, as it is known to occur in the troposphere, but the presence of such reactants in plants has yet to be established. The chemistry of NO2-IPs suggests they may behave as electrophilic signaling molecules with downstream effects similar to those of nitro-fatty acids in animals. Thus, the objective of this research was to verify the premise that NO and isoprene do react and subsequently produce compounds that participate in stress-signaling response in plants. This included identification of the products and their effects on viability and root abscission in response to heat stress in the water fern Azolla filiculoides. Procedure: Biological levels of NO, isoprene and ambient O2 were combined in a flask and incubated at 20°C and 40°C. Pentane was used to simulate the lipid content in plant leaves. Reactions were carried out for 1.5 hours, with samples taken every 0.5 hours for gas chromatography-mass spectrometry (GC-MS), infrared spectroscopy (IR), and nuclear magnetic resonance (1H-NMR) analyses. The biological activity of the in vitro products under high heat and high light intensity was then analyzed in Azolla filiculoides via a root abscission assay and viability assay. Findings: GC-MS results, including positive identification of limonene, a monoterpene previously reported to confer protection against thermal damage, indicate isoprene polymerization. Unexpectedly, limonene was produced only when NO was included in the reaction mix, indicating an alternative pathway to monoterpene formation mediated by reactive nitrogen species. Five other compounds were identified in the in vitro products; one being a catechol derivative that could protect against physical damage. Nitrated products were found in GC-MS analysis of the condensed product mixture. Exposure to the in vitro product mixtures did not affect the abscission rate, but improved viability of plants subjected to high heat and high light intensity treatment. Conclusions: These results suggest that under aerobic conditions NO and isoprene should react in plant membranes to form products with the potential to act as signals or confer heat tolerance.Halahan, Jane A. 2013. In vitro Formation of Isoprene Derivatives in Conditions Simulating Membranes of Plants under Heat Stress. Department of Biology, Sonoma State University

Opinion on the problem of academic integrity during distance learning in the quarantine conditions

In the context of Covid-19 pandemic, after announcement of quarantine, educational institutions in Ukraine were forced to move on a distance learning, which led to the search for methods of control, which are focused on the higher education products of intellectual property in the conditions of rapid development communications with other people's ideas, opinions and completed intellectual products in the form of presentations, scientific works, etc. Classical definition concept of academic integrity, according to some authors, is based on a combination of such fundamental virtues as honesty, trust, justice, respect and responsibility, later, in 2013, supplemented by a new, sixth – courage [1, p. 11]. Given current state of the problem of academic integrity in a quarantine, it should be noted the students’ need to work with resources in the library of a higher education institution remotely

The use of e-learning strategy in teaching foreign languages at the higher educational institution

The requirements of the era of globalization and internationalization set before Ukrainian universities the goal of creating a multilingual educational space that promotes the integration of Ukraine into the international scientific and educational community and promotes the study of the Ukrainian language as a foreign language for intercultural understanding and fruitful cooperation. The article is devoted to the use of e-learning strategy in teaching foreign languages in a multilingual educational space. This study aims to introduce an e-learning course containing educational and control materials given in an effective interactive form