DISCOURSE AND PARTICIPATION IN ESL FACE-TO-FACE AND WRITTEN ELECTRONIC CONFERENCES

This study was a comparative investigation of face-to-face and written electronic conferences. The participants were advanced English as a second language (hereafter: ESL) students. The two types of conferences were compared in terms of textual features and participation. There was no statistically significant difference in the total number of words that students produced in an equivalent amount of time in the two types of conferences. The discourse in written electronic conferences displayed greater lexical range, and students in these conferences produced more discourse demonstrating interactive competence. The statistically significant finding of increased lexical range in written electronic conferences persisted even when the interactive discourse was eliminated from the conference transcripts and the transcripts were reanalyzed. This finding suggests that, during written electronic conferences, students were better able to use and practice a wider range of vocabulary related to the topics. For one of the groups, participation in written electronic conferences was more balanced among students, while for the other group participation was about equally balanced regardless of the conference setting. This last finding came as a surprise and points to a need for further research into variables that might mediate balanced participation in face-to-face and written electronic conferences

Distribution of RET proto-oncogene variants in children with appendicitis

Background: In addition to patient-related systemic factors directing the immune response, the pathomechanisms of appendicitis (AP) might also include insufficient drainage leading to inflammation caused by decreased peristalsis. Genetic predisposition accounts for 30%–50% of AP. M. Hirschsprung (HSCR), also characterized by disturbed peristalsis, is associated with variants in the RET proto-oncogene. We thus hypothesized that RET variants contribute to the etiology of AP. Methods: DNA from paraffin-embedded appendices and clinical data of 264 children were analyzed for the RET c.135A>G variant (rs1800858, NC_000010.11:g.43100520A>G). In 46 patients with gangrenous or perforated AP (GAP), peripheral blood DNA was used for RET sequencing. Results: Germline mutations were found in 13% of GAP, whereas no RET mutations were found in controls besides the benign variant p.Tyr791Phe (NC_000010.11:g.43118460A>T). In GAP, the polymorphic G-allele in rs2435352 (NC_000010.11:g.43105241A>G) in intron 4 was underrepresented (p = 0.0317). Conclusion: Our results suggest an impact of the RET proto-oncogene in the etiology of AP. Mutations were similar to patients with HSCR but no clinical features of HSCR were observed. The pathological phenotypes in both populations might thus represent a multigenic etiology including RET germline mutations with phenotypic heterogeneity and incomplete penetrance

Do Fleas Affect Energy Expenditure of Their Free-Living Hosts?

Parasites can cause energetically costly behavioural and immunological responses which potentially can reduce host fitness. However, although most laboratory studies indicate that the metabolic rate of the host increases with parasite infestation, this has never been shown in free-living host populations. In fact, studies thus far have shown no effect of parasitism on field metabolic rate (FMR).We tested the effect of parasites on the energy expenditure of a host by measuring FMR using doubly-labelled water in free-living Baluchistan gerbils (Gerbillus nanus) infested by naturally occurring fleas during winter, spring and summer. We showed for the first time that FMR of free-living G. nanus was significantly and positively correlated with parasite load in spring when parasite load was highest; this relationship approached significance in summer when parasite load was lowest but was insignificant in winter. Among seasons, winter FMRs were highest and summer FMRs were lowest in G. nanus.The lack of parasite effect on FMR in winter could be related to the fact that FMR rates were highest among seasons. In this season, thermoregulatory costs are high which may indicate that less energy could be allocated to defend against parasites or to compensate for other costly activities. The question about the cost of parasitism in nature is now one of the major themes in ecological physiology. Our study supports the hypothesis that parasites can elevate FMR of their hosts, at least under certain conditions. However, the effect is complex and factors such as season and parasite load are involved

Assessing the Benefit of Prewriting Conferences on Drafts

This chapter reports on a comparative study of face-to-face (FTF) and written electronic (WE) conferences as pre-writing activities in the English as a Second Language (ESL) classroom. Twenty-seven intermediate to advanced students participated in the study over a 4 week period. Latent semantic analysis and corpus linguistics measures were used to compare the extent to which the first drafts incorporated the terms and ideas introduced during the 2 types of conferences. Although no difference was found in the length, or semantic or lexical complexity of first drafts, the results indicated greater lexical and semantic similarity between FTF pre-writing conferences and subsequent drafts. In other words, students made better use of the terms and ideas introduced during the FTF conferences when individually writing first drafts. Reasons why this may have been the case are suggested, and directions for further research are offered.</jats:p

Comparing ESL electronic and face-to-face pre-writing conferences and first drafts : discourse, participation, and idea transfer /

This study was a comparative investigation of face-toface (i.e., proximate) and computer-mediated written (i.e., graphic) pre-writing conferences. The participants in this study were advanced English as a second language students. The 2 types of conferences were compared in terms of textual features, participation, and the . degree to which they were on topic. Moreover, drafts written after the 2 types of conferences were compared in terms of textual features, and the degree to which they were related to the conferences. Students produced an equivalent amount of discourse in an equivalent amount of time in the 2 types of conferences. The discourse in graphic conferences displayed greater lexical range, and some evidence suggests that it was less on-topic. Both these results likely occurred because the graphic conferences contained more discourse demonstrating interactive competence. Participation in graphic conferences was found to be as balanced or more balanced among students, and among students and the group leader combined. Overall, the drafts produced after the 2 types of conferences were of equivalent length and topical range, but some evidence suggests that drafts written after proximate conferences were more related to the conferences

DISCOURSE AND PARTICIPATION IN ESL FACE-TO-FACE AND WRITTEN ELECTRONIC CONFERENCES

This study was a comparative investigation of face-to-face and written electronic conferences. The participants were advanced English as a second language (hereafter: ESL) students. The two types of conferences were compared in terms of textual features and participation. There was no statistically significant difference in the total number of words that students produced in an equivalent amount of time in the two types of conferences. The discourse in written electronic conferences displayed greater lexical range, and students in these conferences produced more discourse demonstrating interactive competence. The statistically significant finding of increased lexical range in written electronic conferences persisted even when the interactive discourse was eliminated from the conference transcripts and the transcripts were reanalyzed. This finding suggests that, during written electronic conferences, students were better able to use and practice a wider range of vocabulary related to the topics. For one of the groups, participation in written electronic conferences was more balanced among students, while for the other group participation was about equally balanced regardless of the conference setting. This last finding came as a surprise and points to a need for further research into variables that might mediate balanced participation in face-to-face and written electronic conferences

Plant succession and soil development on the foreland of the Morteratsch glacier (Pontresina, Switzerland): straight forward or chaotic?

As study area we selected the glacier foreland of Morteratsch (approx. 1900–2100 m a.s.l.) near Pontresina northwest of the Bernina pass, Upper Engadine, Grisons (Switzerland). The aim of this study is a multimethodological approach using floristic inventories, vegetation and soil mapping of the pro-glacial area in order to detect crucial parameters controlling plant resettlement in recently deglaciated areas as related to time, local microtopography and soil development. The following methodological approaches were included in this study: (i) floristic relevees along a chronosequence covering 134 years (1857–1990); (ii) dendrochronological data on tree establishment, collected on a grid with a mesh width of 40 m in the area, which became ice-free between 1857 and 1980; (iii) vegetation mapping; (iv) soil analyses including physical and chemical properties of 11 typical profiles; (v) soil mapping and (vi) data evaluation using GIS. Retreating glaciers successively expose mineral substrates that are colonised within a few years by vascular plants, mosses, lichens and soil biota. With increasing plant cover, also the abundance of soil organic matter increases. At first sight, the large-scale patterns of vegetation and soil seem to be driven by the time since deglaciation, whereas the small scale patterns may appear chaotic since they depend on local site conditions, which may change dramatically over short distances. The large-scale pattern seems to develop as follows. About 7 years after deglaciation the first pioneer plants establish themselves and form after an additional 20 years period the Epilobietum fleischeri community, which today dominates the recently deglaciated areas, but may be found in patches more or less on the whole pro-glacial area. By contrast, the first elements of the short living Oxyrietum digynae community appear approximately 10 years after deglaciation and persist for only about 30 years. Dendrochronology showed that the first European larch and Swiss stone pine trees established themselves 15 and 31 years, respectively, after deglaciation. Surprisingly, on the study area, Swiss stone pine is about twice as frequent as the typical pioneer species European larch (88 stems per ha vs. 45 stems per ha), despite the fact that larch starts earlier and grows faster than Swiss stone pine (annual height increment: 21 cm vs. 8 cm). Up-to-now, however, nowhere in the 150-year-old glacier foreland a near-to-mature larch-Swiss stone pine forest can be found. Besides large-scale factors such as time since deglaciation, topography and disturbance (floods, rockfalls, avalanches), also small-scale factors such as grain size and water content of the substrate, micro-relief and micro-climate seem to be crucial for the development of both vegetation and soil. Time since deglaciation and a straightforward single-pathway succession model are clearly not sufficient for understanding the small-scale patterns of succession. A non-linear succession model with different starting points and different pathways of potential primary successions for the different ecological niches is more promising for describing accurately the spatio-temporal vegetation dynamics of the pro-glacial area of Morteratsch