Doctor of Philosophy

dissertationThe present study investigated the effects of the explicit teaching of formulaic sequences (i.e., academic and topic-induced) on L2 writing. The research examined separately the effects of the treatment on the students' abilities to produce the target formulaic sequences in controlled (i.e., C-tests) and uncontrolled situations (i.e., essays), and to produce better quality essays. The study, through posttreatment interviews, also attempted to glean insights into the approaches L2 writers use for the production of the target formulaic sequences. The study found that the students in the treatment condition performed at a significantly higher level than the students in the control condition on measures of the production of academic formulaic sequences in a controlled situation and the production of topic-induced formulaic sequences in controlled and uncontrolled situations, but there were no significant differences between the groups on the measures of students' abilities to produce academic formulaic sequences in an uncontrolled situation and to produce better quality writing. The results of the study suggest that the explicit instruction facilitated learning of the target formulaic sequences when the learning is measured by a test. Most importantly, the study found that explicit instruction helped students become familiar enough with the formulaic sequences to recognize their usefulness and employ them in their essays. The results indicated that the instructional approach helped low performing writers produce iv essays of better quality and high performing writers increase the awareness of the frequencies and functions of the formulaic sequencers in expert writers' texts. The findings from the interviews indicated that the students' abilities to produce the academic and topic-induced formulaic sequences in their compositions may depend on the students' perceived need to use them in their writing, and that students' abilities to produce the academic formulaic sequences in essays may be influenced by the interaction of students' awareness of the frequency and functions of academic formulaic sequences and their motivation to sound academic in their writing. The study results suggest that the instructional approach may be helpful for the students' learning of formulaic sequences for the purposes of writing and should be the focus of future experimental research

Radioactive Isotopes in Soils and Their Impact on Plant Growth

In 1999, Serbia was bombarded by NATO. One of the cities most affected by the consequences of bombardment with uranium is the city of Vranje, where the consequences are felt even today. Due to the influence of uranium, the mortality rate has increased. This paper presents the effects of some of the radionuclides that have contaminated the soil, as well as the connection between soil and plants that grow on that soil. The performed measurements of radionuclides (226Ra, 40K, 232Th, 238U, and 235U). The results show that the content of each of these radionuclides has different concentrations, but what is important is that some values are even below the detection limit, corn <0.06 235U on the location Korbevac and wheat <0.04 235U on the location Bujkovac. On the three and all of these gated locations, the calculated values of the transfer factors for 40K were in the range of 0.144–0.392, while in the case of 226Ra, the transfer factors ranged from 0.008 to 0.074. Only one value (0.051) was obtained for the transfer factor of 232Th. Specific activities of 137Cs, as well as uranium isotopes, in all the investigated cereal samples, were below minimal detectable activity concentrations. The ratio of radionuclides in soil and plants is of great importance for human nutrition