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The transverse 14 N relaxation times for dilute acetonitrile in water-1-propanol mixtures were measured as a function of solvent composition. The rotational correlation times were evaluated. Since the results cannot be explained by the hydrodynamic theory alone, application of dielectric friction theory is proposed.

Carbon-13 spin-lattice relaxation times and nuclear Overhauser enhancement factors are reported for sucrose and a disaccharide methyl glycoside dissolved in a 7:3 molar solvent mixture of D2O and DMSO-d6 at several magnetic fields. Data which correspond to both sides of the maximum in the T1−1 versus the inverse temperature curves were collected in the temperature range of −15 to + 30°C. Rotational diffusion models are used to determine the overall and internal dynamics of the molecules. The analysis gives an estimate of the rapid initial averaging due to internal fluctuations and activation energies for the overall and methyl rotation.

We present here a set of 13C-direct detected NMR experiments to facilitate the resonance assignment of RNA oligonucleotides. Three experiments have been developed: (1) the (H)CC-TOCSY-experiment utilizing a virtual decoupling scheme to assign the intraresidual ribose 13C-spins, (2) the (H)CPC-experiment that correlates each phosphorus with the C4′ nuclei of adjacent nucleotides via J(C,P) couplings and (3) the (H)CPC-CCH-TOCSY-experiment that correlates the phosphorus nuclei with the respective C1′,H1′ ribose signals. The experiments were applied to two RNA hairpin structures. The current set of 13C-direct detected experiments allows direct and unambiguous assignment of the majority of the hetero nuclei and the identification of the individual ribose moieties following their sequential assignment. Thus, 13C-direct detected NMR methods constitute useful complements to the conventional 1H-detected approach for the resonance assignment of oligonucleotides that is often hindered by the limited chemical shift dispersion. The developed methods can also be applied to large deuterated RNAs. Electronic supplementary material The online version of this article (doi:10.1007/s10858-010-9429-5) contains supplementary material, which is available to authorized users.

Using molecular dynamics simulations, the motion and intermolecular interactions of the ions of silver nitrate are studied in aqueous solution and compared to the results obtained from simulations of molten AgNO3. The particularly interesting and experimentally frequently studied modes of reorientational motion (in-plane and end-over-end) of the planar nitrate ion have been determined from the simulation results. In accordance with earlier experimental results, the correlation times for the end-over-end rotation in aqueous solution are longer than those for the in-plane rotation, while the opposite is found to hold in the melt. In addition, the rotational motion of the nitrate ion in aqueous solution is experimentally studied using 14N relaxation measurements. Good agreement is found between the reorientational correlation times obtained from MD simulations and from NMR relaxation measurements.

With the introduction of Computer Science (CS) into curricula worldwide, researchers have investigated whether CS could be introduced transversally, as a support other disciplines. Few however consider both student learning and the teachers’ perspective in their assessments. In a co-constructive approach to translational research, we collaborated with teachers, in two case studies involving two classes each, to investigate how CS content could be used transversally. More specifically, teacher inputs and student learning data were combined in a mixed methods analysis to determine whether two CS Unplugged (CSU) activities from the curriculum could be leveraged to teach disciplinary content in primary school. The findings indicated that the CSU activities could be leveraged for maths and spelling, but require validation at a larger scale. More important, though, are the takeaways of the co-constructive experience with teachers. Interestingly the benefits of co-construction went both ways. While researchers gained a deeper understanding of the effectiveness of the activities, teachers i) appreciated having detailed student learning analyses, devoid of biases and impressions, ii) changed their perspective about researchers, and iii) were open to other collaborative research initiatives which they found to be drivers of change and innovation in their practice. The way co-construction was approached also impacted the teachers’ perception of their experience. Indeed, while one study was researcher-driven and included teachers, the other was teacher-driven and included researchers. When teacher-driven, the teachers felt they had a more active role, thus reflecting more on the study design, results and implications. Provided the positive impact that co-construction may have on innovation in teacher practices, different co-construction modalities must be investigated, as well as their implications on all stakeholders, including researchers.

In this paper we examine the impacts of the global pandemic in 2020 on different levels of education system, particularly looking at the changes in teaching practice. The health emergency caused closure of schools, and online distance education became a temporary solution, creating discomfort for many teachers for whom this was the first time engaged with online education. In our research we investigated two important dimensions, namely, how technology was used and what the newfound distance meant in terms of the teacher-student relationship. The article offers insights into experiences of teaching from lockdown reported by 41 teachers at primary, vocational and higher education level in the region of Vaud, Switzerland. This comparative qualitative research has provided an opportunity for an in-depth analysis of the main similarities and differences at three distinctly different educational levels and a possibility to learn more about common coping practices in teaching. The study gives a contribution to a lack of comparative studies of teacher experiences at different educational levels. Results show two dimensions in handling the lockdown crisis: mastering the digital tools and the importance of student–teacher interaction. Whilst the interviewed teachers largely overcame the challenges of mastering digital tools, optimizing the quality interaction and ensuring the transactional presence online remained a problem. This indicates the importance of the social aspect in education at all levels, and implies that teacher support needs to expand beyond technical pedagogical knowledge of online distance education.