Motive-demand dynamics creating a social context for students’ learning experiences in a making and design environment

Making and design environments, often referred to as makerspaces, have aroused recent educational interest. These environments typically consist of spaces that support interest-driven engagement in hands-on creative activities with a range of digital artefacts. Although a variety of benefits from participating in making and design activities have been proposed, we currently have limited understanding of students’ learning experiences in makerspaces situated in schools. Following Hedegaards’ conceptualisations, we investigate motive-demand dynamics in students’ social activity in a school-based digital making and design environment, ‘The FUSE Studio’. We highlight our findings via vignettes selected from 65 h of video recordings of 94 students (aged between 9 and 12 years old) carrying out activities; the recordings were collected intermittently from an elective course over one semester. Our study illustrates how the students’ learning experiences were shaped through tension-laden interplay between the motives and demands of their activity situated across personal, relational and institutional contexts. The findings make visible how established ways of working and being at school interacted and came into tension with the students’ motive orientations, thereby limiting and at times transforming the social context of their learning. Our work also demonstrates how the analysis of motive-demand dynamics offers one useful conceptual tool to unpack students’ learning experiences in novel learning environments.Peer reviewe

Interdependence of magnetism and superconductivity in the borocarbide TmNi2B2C

We have discovered a new antiferromagnetic phase in TmNi2B2C by neutron diffraction. The ordering vector is Q_A = (0.48,0,0) and the phase appears above a critical in-plane magnetic field of 0.9 T. The field was applied in order to test the assumption that the zero-field magnetic structure at Q_F = (0.094,0.094,0) would change into a c-axis ferromagnet if superconductivity were destroyed. We present theoretical calculations which show that two effects are important: A suppression of the ferromagnetic component of the RKKY exchange interaction in the superconducting phase, and a reduction of the superconducting condensation energy due to the periodic modulation of the moments at the wave vector Q_A

Use of tiling array data and RNA secondary structure predictions to identify noncoding RNA genes

<p>Abstract</p> <p>Background</p> <p>Within the last decade a large number of noncoding RNA genes have been identified, but this may only be the tip of the iceberg. Using comparative genomics a large number of sequences that have signals concordant with conserved RNA secondary structures have been discovered in the human genome. Moreover, genome wide transcription profiling with tiling arrays indicate that the majority of the genome is transcribed.</p> <p>Results</p> <p>We have combined tiling array data with genome wide structural RNA predictions to search for novel noncoding and structural RNA genes that are expressed in the human neuroblastoma cell line SK-N-AS. Using this strategy, we identify thousands of human candidate RNA genes. To further verify the expression of these genes, we focused on candidate genes that had a stable hairpin structures or a high level of covariance. Using northern blotting, we verify the expression of 2 out of 3 of the hairpin structures and 3 out of 9 high covariance structures in SK-N-AS cells.</p> <p>Conclusion</p> <p>Our results demonstrate that many human noncoding, structured and conserved RNA genes remain to be discovered and that tissue specific tiling array data can be used in combination with computational predictions of sequences encoding structural RNAs to improve the search for such genes.</p

A Helium-Surface Interaction Potential of Bi2_2Te3_3(111) from Ultrahigh-Resolution Spin-Echo Measurements

We have determined an atom-surface interaction potential for the He$-$Bi$_2$Te$_3$(111) system by analysing ultrahigh resolution measurements of selective adsorption resonances. The experimental measurements were obtained using $^3$He spin-echo spectrometry. Following an initial free-particle model analysis, we use elastic close-coupling calculations to obtain a three-dimensional potential. The three-dimensional potential is then further refined based on the experimental data set, giving rise to an optimised potential which fully reproduces the experimental data. Based on this analysis, the He$-$Bi$_2$Te$_3$(111) interaction potential can be described by a corrugated Morse potential with a well depth $D=(6.22\pm0.05)~\mathrm{meV}$, a stiffness $\kappa =(0.92\pm0.01)~\mathrm{\AA}^{-1}$ and a surface electronic corrugation of $(9.6\pm0.2)$% of the lattice constant. The improved uncertainties of the atom-surface interaction potential should also enable the use in inelastic close-coupled calculations in order to eventually study the temperature dependence and the line width of selective adsorption resonances