Term-time Employment and Student Attainment in Higher Education

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The use of picture cards to elicit postgraduate dental student feedback

The aim of this study was to elicit information about the use of picture cards to stimulate student feedback following a postgraduate dental course. Twenty-nine general dental practitioners (GDPs) volunteered for the study. Following an explanation of how this style of feedback worked, students were asked to choose a picture card from those available and use that image to stimulate their feedback. An independent interviewer introduced the topic and gathered comments in the form of qualitative data, generated by pre-formed questions. 93% (n = 26) questionnaires were completed and returned. 77% (n = 20) GDPs reported enjoying giving their feedback by ‘picture card’ technique; 83% (n = 20) reported this form of feedback stimulated their thoughts. Qualitative data were analysed thematically. Some GDPs felt the picture cards helped them formulate their feedback, others felt being able to give feedback to a third party they did not know was beneficial and giving feedback as a group was helpful. This novel approach of using picture cards to stimulate feedback was well received by these GDPs. A mixed result as to the value of this style of feedback was evident. A group feedback session facilitated by a stranger was considered to be a valuable approach to take

Impact of Haptic Feedback in High Latency Teleoperation for Space Applications

Remote manipulation is a key enabler for upcoming space activities such as in-orbit servicing and manufacture (IOSM). However, due to the large distances involved, these systems encounter unavoidable signal delays which can lead to poor performance and users adopting a disjointed, ‘move-and-wait’ style of operation. We use a robot arm teleoperated with a haptic controller to test the impact of haptic feedback on delayed (up to 2.6 s: Earth-Moon communications) teleoperation performance for two example IOSM-style tasks.This user study showed that increased latency reduced performance in all of metrics recorded. In real-time teleoperation, haptic feedback showed improvements in success rate, accuracy, contact force, velocity, and trust, but, of these, only the improvements to contact forces and moving velocity were also seen at higher latencies. Accuracy and trust improvements were lost, or even reversed, at higher latencies. Results varied between the two tasks, highlighting the need for further research into the range of task types to be encountered in teleoperated space activities. This study also provides a framework by which to explore how features other than haptic feedback can impact both performance and trust in delayed teleoperatio

Observation of helimagnetism in the candidate ferroelectric CrI2_2

CrI$_{2}$ is a quasi-one dimensional (1D) van der Waals (vdW) system that exhibits helimagnetism that propagates along the ribbons. This was determined from neutron time-of-flight diffraction measurements. Below $T_N=17$ K, a screw-like helimagnetic order develops with an incommensurate wavevector of $\mathbf{q} \approx (0.2492,0,0)$ at 8 K. Using density functional theory (DFT)$+U$ calculations, the $J_{1}$-$J_{2}$ model was leveraged to describe the helimagnetism, where $J_{1} (> 0)$ and $J_2 (< 0)$ correspond, respectively, to a ferromagnetic nearest neighbor (NN) and antiferromagnetic next-nearest neighbor (NNN) intrachain interaction. The DFT$+U$ calculations predict that bulk CrI$_2$ in the orthorhombic $Cmc2_1$ crystal structure satisfies the $|J_2| > |J_1|/4$ condition, which favors formation of helimagnetic order.Comment: main pdf file includes supplemen

Elicitation of trustworthiness requirements for highly dexterous teleoperation systems with signal latency

IntroductionTeleoperated robotic manipulators allow us to bring human dexterity and cognition to hard-to-reach places on Earth and in space. In long-distance teleoperation, however, the limits of the speed of light results in an unavoidable and perceivable signal delay. The resultant disconnect between command, action, and feedback means that systems often behave unexpectedly, reducing operators' trust in their systems. If we are to widely adopt telemanipulation technology in high-latency applications, we must identify and specify what would make these systems trustworthy.MethodsIn this requirements elicitation study, we present the results of 13 interviews with expert operators of remote machinery from four different application areas—nuclear reactor maintenance, robot-assisted surgery, underwater exploration, and ordnance disposal—exploring which features, techniques, or experiences lead them to trust their systems.ResultsWe found that across all applications, except for surgery, the top-priority requirement for developing trust is that operators must have a comprehensive engineering understanding of the systems' capabilities and limitations. The remaining requirements can be summarized into three areas: improving situational awareness, facilitating operator training, and familiarity, and easing the operator's cognitive load.DiscussionWhile the inclusion of technical features to assist the operators was welcomed, these were given lower priority than non-technical, user-centric approaches. The signal delays in the participants' systems ranged from none perceived to 1 min, and included examples of successful dexterous telemanipulation for maintenance tasks with a 2 s delay. As this is comparable to Earth-to-orbit and Earth-to-Moon delays, the requirements discussed could be transferable to telemanipulation tasks in space

Lattice and magnetic dynamics in YVO3 Mott insulator studied by neutron scattering and first-principles calculations

The Mott insulator YVO3 with TN = 118 K is revisited to explore the role of spin, lattice and orbital correlations across the multiple structural and magnetic transitions observed as a function of temperature. Upon cooling, the crystal structure changes from orthorhombic to monoclinic at 200 K, and back to orthorhombic at 77 K, followed by magnetic transitions. From the paramagnetic high temperature phase, C-type ordering is first observed at 118 K, followed by a G-type spin re- orientation transition at 77 K. The dynamics of the transitions were investigated via inelastic neutron scattering and first principles calculations. An overall good agreement between the neutron data and calculated spectra was observed. From the magnon density of states, the magnetic exchange constants were deduced to be Jab = Jc = -5.8 meV in the G-type spin phase, and Jab = -3.8 meV, Jc = 7.6 meV at 80 K and Jab = -3.0 meV, Jc = 6.0 meV at 100 K in the C-type spin phase. Paramagnetic scattering was observed in the spin ordered phases, well below the C-type transition temperature, that continuously increased above the transition. Fluctuations in the temperature dependence of the phonon density of states were observed between 50 and 80 K as well, coinciding with the G-type to C-type transition. These fluctuations are attributed to optical oxygen modes above 40 meV, from first principles calculations. In contrast, little change in the phonon spectra is observed across TN.This work has been supported by the Department of Energy, Grant number DE-FG02-01ER4592. This work was also partly supported by the Materials Research Sci- ence and Engineering Centers, National Science Founda- tion, Grant number DMR-1720595, by providing sample used in this work and by the National Institute of Stan- dards and Technology, US Department of Commerce, in providing computing resources for DFT calculations used in this work.Center for Dynamics and Control of Material

Effect of wearing a face mask on hand-to-face contact by children in a simulated school environment: the Back-to-School COVID-19 Simulation Randomized Clinical Trial

Importance Wearing a face mask in school can reduce SARS-CoV-2 transmission but it may also lead to increased hand-to-face contact, which in turn could increase infection risk through self-inoculation. Objective To evaluate the effect of wearing a face mask on hand-to-face contact by children while at school. Design, Setting, and Participants This prospective randomized clinical trial randomized students from junior kindergarten to grade 12 at 2 schools in Toronto, Ontario, Canada, during August 2020 in a 1:1 ratio to either a mask or control class during a 2-day school simulation. Classes were video recorded from 4 angles to accurately capture outcomes. Interventions Participants in the mask arm were instructed to bring their own mask and wear it at all times. Students assigned to control classes were not required to mask at any time (grade 4 and lower) or in the classroom where physical distancing could be maintained (grade 5 and up). Main Outcomes and Measures The primary outcome was the number of hand-to-face contacts per student per hour on day 2 of the simulation. Secondary outcomes included hand-to-mucosa contacts and hand-to-nonmucosa contacts. A mixed Poisson regression model was used to derive rate ratios (RRs), adjusted for age and sex with a random intercept for class with bootstrapped 95% CIs. Results A total of 174 students underwent randomization and 171 students (mask group, 50.6% male; control group, 52.4% male) attended school on day 2. The rate of hand-to-face contacts did not differ significantly between the mask and the control groups (88.2 vs 88.7 events per student per hour; RR, 1.00; 95% CI, 0.78-1.28; P = >.99). When compared with the control group, the rate of hand-to-mucosa contacts was significantly lower in the mask group (RR, 0.12; 95% CI, 0.07-0.21), while the rate of hand-to-nonmucosa contacts was higher (RR, 1.40; 95% CI, 1.08-1.82). Conclusions and Relevance In this clinical trial of simulated school attendance, hand-to-face contacts did not differ among students required to wear face masks vs students not required to wear face masks; however, hand-to-mucosa contracts were lower in the face mask group. This suggests that mask wearing is unlikely to increase infection risk through self-inoculation. Trial Registration ClinicalTrials.gov Identifier: NCT0453125