The main goal of this research was to determine the relationship among chemical structure, bioactivity and temperature of chamomile during subcritical water extraction in isobaric conditions (45 bar) at seven different temperatures (65-210 °C). The influence of temperature on phenolic profiles was defined by UHPLC-HESI-MS/MS. The overall results indicate that the presence of conjugated double bonds, side chains, glucose moiety or ether moiety in molecules influence the efficiency of polyphenols' extraction in subcritical water. In terms of antioxidant activity, the extracts were the most active towards ABTS radicals (IC = 7.3-16.8 µg/mL), whereby temperature of 150 °C was optimal. On the other hand, the extracts obtained at 115 °C showed highest cytotoxicity. Inhibition of α-amylase and α-glucosidase was the highest at 65 and 85 °C, i.e. 0.51 and 4.13 mmolAE/g, respectively. Activity against tyrosinase was the highest at 210 °C (17.92 mgKAE/g). The data showed that different non-phenolic compounds may also participate in bio-activities of the extracts.

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The circumstances of the Covid-19 pandemic have brought about drastic changes in all aspects of human activities, including education. The challenges faced by educators worldwide have been to arrange online classes and provide an effective and motivating learning environment. The research presented in this paper analyzes student motivation for learning English in the setting of online classes, compared to traditional (face-to-face) classes. The main aim of this paper is to identify the factors of both online and traditional classes that positively affect student motivation in order to integrate them into an effective learning environment in the future. The focus is on factors of motivation that have been significantly affected by the pandemic, including the factors of physical conditions, methods of teaching and affective and interpersonal factors. This research was conducted at the Faculty of Technology and Faculty of Agriculture, University of Novi Sad, and included 120 engineering students who attended online English language courses. A questionnaire, used as a research instrument, consisted of statements related to the impact of online vs. traditional classes on student motivation to learn English, graded on a 6-point Likert scale. The obtained results indicated that students find the use of modern technology and applications quite motivating for learning English and that a certain flexibility, referring to the physical factors, could also be integrated into traditional classes. Interpersonal factors, such as face-to-face interaction with the teacher and peers, proved to be very important for student motivation. The research also showed that online classes reduce students’ speaking anxiety, but that the issue of anxiety in both types of classes requires closer attention and should be addressed by raising student awareness of this issue and employing methods that would encourage students to participate in the classes more actively.

‘Noun + Noun’ compounds are among the most common and productive structures in modern English. Due to their complexity and potential ambiguity, they represent a challenge for English language learners, especially if such compounds are generally untypical and unproductive in the learners’ mother tongue, as the case is with the Serbian. The aim of this research is to examine how engineering students understand and translate ‘N+N’ structures in the context of English for Specific Purposes, focusing on binominal compounds and compounds with more than two constituents. The research method is the analysis of a translation test from English to Serbian. The results show that students need to receive more input about the semantic and syntactic properties of these structures and develop learning strategies that would help them to fully comprehend this type of compounds and provide their correct translations, focusing on their meaning instead of form.

Course evaluation has held a prominent position in higher education in the past few decades, yet there exist certain deficiencies pertaining to its design and implementation in some contexts, such as tertiary English for specific purposes (ESP) programs in Serbia and Slovenia. This study focused on ESP course evaluation