331 research outputs found

    Exploring the views of students on the use of Facebook in university teaching and learning

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    Facebook use among students is almost ubiquitous; however, its use for formal academic purposes remains contested. Through an online survey monitoring student use of module Facebook pages and focus groups, this study explores students’ current academic uses of Facebook and their views on using Facebook within university modules. Students reported using Facebook for academic purposes, notably peer–peer communication around group work and assessment – a use not always conceptualised by students as learning. Focus groups revealed that students are not ready or equipped for the collaborative style of learning envisaged by the tutor and see Facebook as their personal domain, within which they will discuss academic topics where they see a strong relevance and purpose, notably in connection with assessment. Students use Facebook for their own mutually defined purposes and a change in student mind- and skill-sets is required to appropriate the collaborative learning benefits of Facebook in formal educational contexts

    Equal latency contours and auditory weighting functions for the harbour porpoise (Phocoena phocoena)

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    Loudness perception by human infants and animals can be studied under the assumption that sounds of equal loudness elicit equal reaction times (RTs). Simple RTs of a harbour porpoise to narrowband frequency-modulated signals were measured using a behavioural method and an RT sensor based on infrared light. Equal latency contours, which connect equal RTs across frequencies, for reference values of 150–200 ms (10 ms intervals) were derived from median RTs to 1 s signals with sound pressure levels (SPLs) of 59–168 dB re. 1 μPa and centre frequencies of 0.5, 1, 2, 4, 16, 31.5, 63, 80 and 125 kHz. The higher the signal level was above the hearing threshold of the harbour porpoise, the quicker the animal responded to the stimulus (median RT 98–522 ms). Equal latency contours roughly paralleled the hearing threshold at relatively low sensation levels (higher RTs). The difference in shape between the hearing threshold and the equal latency contours was more pronounced at higher levels (lower RTs); a flattening of the contours occurred for frequencies below 63 kHz. Relationships of the equal latency contour levels with the hearing threshold were used to create smoothed functions assumed to be representative of equal loudness contours. Auditory weighting functions were derived from these smoothed functions that may be used to predict perceived levels and correlated noise effects in the harbour porpoise, at least until actual equal loudness contours become available

    Context-dependent effects on spatial variation in deer-vehicle collisions

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    Identifying factors that contribute to the risk of wildlife‐vehicle collisions (WVCs) has been a key focus of wildlife managers, transportation safety planners and road ecologists for over three decades. Despite these efforts, few generalities have emerged which can help predict the occurrence of WVCs, heightening the uncertainty under which conservation, wildlife and transportation management decisions are made. Undermining this general understanding is the use of study area boundaries that are incongruent with major biophysical gradients, inconsistent data collection protocols among study areas and species‐specific interactions with roads. We tested the extent to which factors predicting the occurrence of deer‐vehicle collisions (DVCs) were general among five study areas distributed over a 11,400‐km2 region in the Canadian Rocky Mountains. In spite of our system‐wide focus on the same genus (i.e., Odocoileus hemionus and O. virginianus), study area delineation along major biophysical gradients, and use of consistent data collection protocols, we found that large‐scale biophysical processes influence the effect of localized factors. At the local scale, factors predicting WVC occurrence varied greatly between individual study areas. Distance to water was an important predictor of WVCs in three of the five study areas, while other variables had modest importance in only two of the five study areas. Thus, lack of generality in factors predicting WVCs may have less to do with methodological or taxonomic differences among study areas than the large‐scale, biophysical context within which the data were collected. These results highlight the critical need to develop a conceptual framework in road ecology that can unify the disparate results emerging from field studies on WVC occurrence

    Vleermuisverblijven Waiboerhoeve en Aver Heino geschikt voor bewoning

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    Tot nu toe zijn er geen vleermuizen vastgesteld in de vleermuisverblijven op Aver Heino en Waiboerhoeve. De temperatuur en luchtvochtigheid geven aan dat de verblijven in principe wel geschikt zijn. Blijkbaar spelen andere factoren een rol

    TEMPRANILLO is a regulator of juvenility in plants

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    Many plants are incapable of flowering in inductive daylengths during the early juvenile vegetative phase (JVP). Arabidopsis mutants with reduced expression of TEMPRANILLO (TEM), a repressor of FLOWERING LOCUS T (FT) had a shorter JVP than wild-type plants. Reciprocal changes in mRNA expression of TEM and FT were observed in both Arabidopsis and antirrhinum, which correlated with the length of the JVP. FT expression was induced just prior to the end of the JVP and levels of TEM1 mRNA declined rapidly at the time when FT mRNA levels were shown to increase. TEM orthologs were isolated from antirrhinum (AmTEM) and olive (OeTEM) and were expressed most highly during their juvenile phase. AmTEM functionally complemented AtTEM1 in the tem1 mutant and over-expression of AmTEM prolonged the JVP through repression of FT and CONSTANS (CO). We propose that TEM may have a general role in regulating JVP in herbaceous and woody species

    Autoregulation of RCO by Low-Affinity Binding Modulates Cytokinin Action and Shapes Leaf Diversity

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    Mechanisms through which the evolution of gene regulation causes morphological diversity are largely unclear. The tremendous shape variation among plant leaves offers attractive opportunities to address this question. In cruciferous plants, the REDUCED COMPLEXITY (RCO) homeodomain protein evolved via gene duplication and acquired a novel expression domain that contributed to leaf shape diversity. However, the molecular pathways through which RCO regulates leaf growth are unknown. A key question is to identify genome-wide transcriptional targets of RCO and the DNA sequences to which RCO binds. We investigate this question using Cardamine hirsuta, which has complex leaves, and its relative Arabidopsis thaliana, which evolved simple leaves through loss of RCO. We demonstrate that RCO directly regulates genes controlling homeostasis of the hormone cytokinin to repress growth at the leaf base. Elevating cytokinin signaling in the RCO expression domain is sufficient to both transform A. thaliana simple leaves into complex ones and partially bypass the requirement for RCO in C. hirsuta complex leaf development. We also identify RCO as its own target gene. RCO directly represses its own transcription via an array of low-affinity binding sites, which evolved after RCO duplicated from its progenitor sequence. This autorepression is required to limit RCO expression. Thus, evolution of low-affinity binding sites created a negative autoregulatory loop that facilitated leaf shape evolution by defining RCO expression and fine-tuning cytokinin activity. In summary, we identify a transcriptional mechanism through which conflicts between novelty and pleiotropy are resolved during evolution and lead to morphological differences between species. Hajheidari et al. identify target genes for the RCO homeodomain protein that drove leaf shape diversity. They show that RCO regulates growth via orchestrating homeostasis for the hormone cytokinin and that it also represses its own transcription via low-affinity binding sites. This autorepression helps delimit RCO expression and shape leaf form
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