First Records of Two Species of the Genus Illinoia Wilson, 1910 (Hemiptera: Aphididae) in Bulgaria

Two aphid species of the genus Illinoia Wilson, 1910 are reported for the first time in Bulgaria, Illinoia (Illinoia) azaleae (Mason, 1925) and Illinoia (Masonaphis) lambersi (MacGillivray, 1960). They are pest mainly on Rhododendron sp. and were collected from important ornamental plants in two garden centres in Sofia and the village of Ravda, Burgas Region. The new records are provided with original illustrations based on Bulgarian materials

Effects of freezing and soil drought on the geochemical fractionation of americium in Fluvisol and Cambisol soils from Bulgaria

Abstract Extreme changes of environmental conditions can alter the soil properties and influence the migration ability and bioavailability of pollutants. Elucidation of the effects of the extreme weather conditions, such as sharp temperature change, drought and floods, on the fractionation of radionuclides in different soil types is especially important for adequate risk assessment after radioactive contamination. The effects of short-term and prolonged freezing and soil drought on the geochemical fractionation of americium in two soil types (Fluvisol and Cambisol, classified according to the World Reference Base for Soil Resources/FAO) from Bulgaria were studied. The changes of the physico-chemical forms of 241Am after storage under different conditions were determined by the sequential extraction procedure and gamma-spectrometric measurements. The impact of the sharp temperature decrease and drought on the association of the radionuclide with the various soil phases was considered in terms of the soil characteristics. The results showed that the risk of increased mobility and bioavailability of americium in the loamy-sand soil with acidic pH and very low cation exchange capacity (CEC) exists under the examined extreme environmental conditions. The soil with sand-loam texture tended to immobilize americium after freeze and drought storage

Addressing cheating in e-assessment using student authentication and authorship checking systems: teachers’ perspectives

Student authentication and authorship checking systems are intended to help teachers address cheating and plagiarism. This study set out to investigate higher education teachers’ perceptions of the prevalence and types of cheating in their courses with a focus on the possible changes that might come about as a result of an increased use of e-assessment, ways of addressing cheating, and how the use of student authentication and authorship checking systems might impact on assessment practice. This study was carried out within the context of the project TeSLA (an Adaptive Trust-based e-assessment System for Learning) which is developing a system intended for integration within an institution’s Virtual Learning Environment (VLE) offering a variety of instruments to assure student authentication and authorship checking. Data was collected at two universities that were trialling the TeSLA system, one in Turkey, where the main modes of teaching are face-to-face teaching and distance education, and one in Bulgaria, where the main modes of teaching are face-to-face teaching and blended learning. The study used questionnaires and interviews, building on existing TeSLA project evaluation activities and extending these to explore the specific areas we wished to examine in more depth. In three of the four contexts cheating was seen by teachers as a serious and growing problem, the exception was the distance education context where the teachers believed that the existing procedures were effective in controlling cheating. Most teachers in all four contexts expected cheating to become a greater problem with increased use of e-assessment. Student authentication was not seen as a major problem in any of the contexts, as this was felt to be well controlled through face-to-face proctored assessments, though the problem of assuring effective authentication was seen by many teachers as a barrier to increased use of e-assessment. Authorship checking was seen as a major issue in all contexts, as copying and pasting from the web, ghost writing and plagiarism were all reported as widely prevalent, and authorship checking was seen as becoming even more important with increased use of e-assessment. Teachers identified a third category of cheating behaviours, which was the accessing of information from other students, from written materials, and from the internet during assessments. Teachers identified a number of approaches to addressing the problem of cheating: education, technology, assessment design, sanctions, policy, and surveillance. Whilst technology was not seen as the most important approach to prevention, student authentication and authorship checking systems were seen as relevant in terms of reducing reliance on face-to-face proctored examinations, and in improving the quality of assessment through supporting the employment of a wider range of assessment methods. The development of authorship checking based on computational linguistic approaches was an area of particular interest. Student authentication and authorship checking systems were not seen as being able to address the third category of cheating behaviours that the study identified

Desing of laboratory for green sand testing

Ingeniería IndustrialIndustria Ingeniaritz

Tinocallis kahawaluokalani (Kirkaldy, 1907)(Hemiptera, Aphididae): A new invasive species in Bulgaria

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