Innovative physics teaching spaces

There are often heated debates around teaching and learning spaces, from collaborative spaces for student centred learning to abolishing teacher centred lecture theatres. In both school and university contexts, economics and practicalities have led to designing multi-purpose learning spaces which can be used by different disciplines and for different purposes. Consequently, it is often a challenge to justify and advocate for dedicated discipline-based laboratory teaching and learning spaces.  In this workshop we will share a particular innovative space specifically designed as a physics laboratory, with the functionality of being used as a recitation/tutorial space, project space as well as for studio teaching with mini lectures.  We will also share our experience of running Physics labs in this space. We will show how particular demands:  to be ‘multipurpose’ across different modes of physics teaching allowing for in-depth learning of physics, be able to accommodate various level of experimental classes, provide ability of skills development including open-ended projects, grant effective teaching technical support, could be implemented in design solutions. We will discuss how features of teaching space influenced teaching modes. Participants are requested to bring designs of their teaching and learning spaces, share experiences of fit-for-purpose learning spaces as well as pick up some tips if designing new learning spaces. In particular, the space could be welcoming, has a pleasant ambience and has been well received by both staff and students. Given the current context of ‘going online’, physical learning spaces need to be something extra special as we move into the future. Bring along your future-looking extra special learning space designs! Intended Audience: University and Secondary-School Physics Educator

Thermal conductivity: Concept and apparatus

The study of the physical mechanisms involved in heat transfer phenomena is important as they influence many aspects of our life. However, thermal physics practicals are one of the most challenging in the Junior Physics lab, mostly due to conceptual difficulty, equipment problems and safety issues. In this presentation we describe one of our new thermal experiments – thermal conductivity. This topic is of considerable pedagogical importance since it requires a good understanding of the physical mechanisms involved in heat transfer and can be exploited in junior and senior physics courses in different ways. This practical consists of two parts – qualitative and quantitative. In the first part we describe how a daily experience such as the touch of hot and cool objects with the hands can be used to learn concepts related to heat transfer. The second part is devoted to quantitative measurements of thermal conductivity. If you apply heat to one end of a copper rod and hold the other end, the atoms in the hot end become excited, i.e., they have higher energy, and share their energies with their neighbours, and they in turn share energy with their neighbours, and so on along the rod. So eventually, your end of the copper rod starts becoming warm. See Abstract PDF for the equation heat flux is determined by. In-house built apparatus consisting of four rods, four heaters, heat sink, and 4 thermal probes provides opportunity to explore Eq1, as we can vary A and k, by varying rod’s diameter and material. Four thermal probes provide temperature gradient. During the practical, students determine the thermal conductivity of each rod using Eq.(1), the heat conduction equation

S ‐Aryl‐ l ‐cysteine sulphoxides and related organosulphur compounds alter oral biofilm development and AI ‐2‐based cell–cell communication

Aims To design and synthesize a library of structurally related, small molecules related to homologues of compounds produced by the plant Petiveria alliacea and determine their ability to interfere with AI ‐2 cell–cell communication and biofilm formation by oral bacteria. Many human diseases are associated with persistent bacterial biofilms. Oral biofilms (dental plaque) are problematic as they are often associated with tooth decay, periodontal disease and systemic disorders such as heart disease and diabetes. Methods and Results Using a microplate‐based approach, a bio‐inspired small molecule library was screened for anti‐biofilm activity against the oral species Streptococcus mutans UA 159 , Streptococcus sanguis 10556 and Actinomyces oris MG 1. To complement the static screen, a flow‐based BioFlux microfluidic system screen was also performed under conditions representative of the human oral cavity. Several compounds were found to display biofilm inhibitory activity in all three of the oral bacteria tested. These compounds were also shown to inhibit bioluminescence by Vibrio harveyi and were thus inferred to be quorum sensing ( QS ) inhibitors. Conclusion Due to the structural similarity of these compounds to each other, and to key molecules in AI ‐2 biosynthetic pathways, we propose that these molecules potentially reduce biofilm formation via antagonism of QS or QS ‐related pathways. Significance and Impact of the Study This study highlights the potential for a non‐antimicrobial‐based strategy, focused on AI ‐2 cell–cell signalling, to control the development of dental plaque. Considering that many bacterial species use AI ‐2 cell–cell signalling, as well as the increased concern of the use of antimicrobials in healthcare products, such an anti‐biofilm approach could also be used to control biofilms in environments beyond the human oral cavity.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/109321/1/jam12616.pd

Evaluating the online teaching experience of University of Sydney staff from 2020-2021: What are the lessons learnt?

This study aimed to address the broad concern of how teaching staff in the higher education sector were impacted during the COVID-19 pandemic in 2020/2021. Importantly, we sought to extend this to consider how reflecting on these experiences has informed future practice or plans for innovation. Invited participants completed an online qualitative questionnaire composed of reflective questions. Respondents (14) included members of the research team from the Faculty of Science and Business School, The University of Sydney. Subsequent deductive thematic coding was undertaken with a focus to identify common experiences and challenges raised (Ryan & Bernard, 2003). In this presentation, we will give an overview of the key findings from this study including the challenges and lessons learnt. In this study there was a degree of concern raised about making the transition from face-to-face teaching to online teaching. This was primarily related to increased workload and lack of engagement with online teaching. However, as respondents went through the process of change, they reported feeling more positive and confident about their ability to use EdTech and make changes in a short space of time. The research has demonstrated a strong resilience of staff in adapting to unforeseen changes such as that experienced by all during the pandemic. REFERENCE Ryan, G. W. & Bernard, H. R. (2003). Techniques to identify themes. Field Methods, 15, 85-109

Particles as probes for complex plasmas in front of biased surfaces

An interesting aspect in the research of complex (dusty) plasmas is the experimental study of the interaction of micro-particles with the surrounding plasma for diagnostic purposes. Local electric fields can be determined from the behaviour of particles in the plasma, e.g. particles may serve as electrostatic probes. Since in many cases of applications in plasma technology it is of great interest to describe the electric field conditions in front of floating or biased surfaces, the confinement and behaviour of test particles is studied in front of floating walls inserted into a plasma as well as in front of additionally biased surfaces. For the latter case, the behaviour of particles in front of an adaptive electrode, which allows for an efficient confinement and manipulation of the grains, has been experimentally studied in dependence on the discharge parameters and on different bias conditions of the electrode. The effect of the partially biased surface (dc, rf) on the charged micro-particles has been investigated by particle falling experiments. In addition to the experiments we also investigate the particle behaviour numerically by molecular dynamics, in combination with a fluid and particle-in-cell description of the plasma.Comment: 39 pages, 16 figures, submitted to New J. Phy

Mode-spectral analysis of 2D Coulomb clusters with fluctuating charges

The mode spectra of small $N = 3, 7, 12$ clusters of dust particles with fluctuating charges are analyzed. Particular attention is paid to the influence of correlated and uncorrelated charge fluctuations on the oscillation mode spectra of these clusters. It is found that the main signature of the correlated charge fluctuations is the shift of the lowest-frequency (shear) mode; other modes are split/shifted according to their mode number and the weight of the shear and compressional parts in their oscillation pattern. This is useful for diagnostics as the character of dust charge fluctuations extracted from the analysis of the cluster mode spectra provides important information on the plasma correlation length

Supplementary Material for: Effect of Fluoride-Containing Toothpastes on Enamel Demineralization and Streptococcus mutans Biofilm Architecture

<p>This study aimed to explore the effect of fluoridated toothpastes on biofilm architecture and enamel demineralization in an in vitro biofilm model. <i>Streptococcus mutans</i> was grown on enamel and treated with slurries of commercial toothpastes, containing SnF₂ or NaF. Water and chlorhexidine were used as negative and positive controls, respectively. The developed biofilms were imaged and enamel demineralization was measured. SnF₂ and NaF toothpaste treatments significantly reduced enamel demineralization, but SnF₂ toothpaste was more effective. Only SnF₂ toothpaste and chlorhexidine treatments caused reductions on biofilm mass and thickness. In conclusion, this biofilm model was able to differentiate the effects of the SnF₂ and NaF toothpastes on biofilm architecture and enamel demineralization.</p