1,638 research outputs found

    Portable LED fluorescence instrumentation for the rapid assessment of potable water quality

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    Characterising the organic and microbial matrix of water are key issues in ensuring a safe potable water supply. Current techniques only confirm water quality retrospectively via laboratory analysis of discrete samples. Whilst such analysis is required for regulatory purposes, it would be highly beneficial to monitor water quality in-situ in real time, enabling rapid water quality assessment and facilitating proactive management of water supply systems. A novel LED-based instrument, detecting fluorescence peaks C and T (surrogates for organic and microbial matter, respectively), was constructed and performance assessed. Results from over 200 samples taken from source waters through to customer tap from three UK water companies are presented. Excellent correlation was observed between the new device and a research grade spectrophotometer (r 2 = 0.98 and 0.77 for peak C and peak T respectively), demonstrating the potential of providing a low cost, portable alternative fluorimeter. The peak C/TOC correlation was very good (r 2 = 0.75) at low TOC levels found in drinking water. However, correlations between peak T and regulatory measures of microbial matter (2 day/3 day heterotrophic plate counts (HPC), E. coli, and total coliforms) were poor, due to the specific nature of these regulatory measures and the general measure of peak T. A more promising correlation was obtained between peak T and total bacteria using flow cytometry. Assessment of the fluorescence of four individual bacteria isolated from drinking water was also considered and excellent correlations found with peak T (Sphingobium sp. (r 2 = 0.83); Methylobacterium sp. (r 2 = 1.0); Rhodococcus sp. (r 2 = 0.86); Xenophilus sp. (r 2 = 0.96)). It is notable that each of the bacteria studied exhibited different levels of fluorescence as a function of their number. The scope for LED based instrumentation for insitu, real time assessment of the organic and microbial matrix of potable water is clearly demonstrated

    Using artificial intelligence-enhanced video feedback for reflective practice in coach development: benefits and potential drawbacks

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    Sports coaching has used video feedback for decades to improve athlete and coach performance. More recently, artificial intelligence (AI) and machine-learning technologies have enabled analytics alongside visual review to accelerate development further. So too in coaching conversations, software allows the implementation of behavioural analytics, tracking speech patterns, body language and facial expressions to deliver performance data measured against core coaching competencies. In this study, we interviewed 15 coaches who used AI-enhanced video review software in coaching sessions with clients over several weeks and reflected on those sessions using the recordings and AI-generated data. Our aim was to discover the benefits and drawbacks of using such an approach in reflective practice. Clear benefits emerged: insights gained from video and data analysis drove deeper reflection and heightened self-awareness; coaches focused on skills development, made specific changes to their practice, developed over time and gained in confidence. Challenges included coaches’ nervousness around using new technology, viewing and analysing their own performance, and a sense that the software does not understand the subtle nuances and context of conversations. Limitations are discussed as well as the implications for coach training, reflective practice and supervision. We suggest possibilities for further study in this area

    A matrix isolation and computational study of molecular palladium fluorides : does PdF₆ exist?

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    Palladium atoms generated by thermal evaporation and laser ablation were reacted with and trapped in F₂ /Ar, F₂ /Ne, and neat F₂ matrices. The products were characterized by electronic absorption and infrared spectroscopy, together with relativistic density functional theory calculations as well as coupled cluster calculations. Vibrational modes at 540 and 617 cm⁻Âč in argon matrices were assigned to molecular PdF and PdF₂ , and a band at 692 cm⁻Âč was assigned to molecular PdF₄ . A band at 624 cm⁻Âč can be assigned to either PdF₃ or PdF₆, with the former preferred from experimental considerations. Although calculations might support the latter assignment, our conclusion is that in these detailed experiments there is no convincing evidence for PdF₆

    Integrating language learning practises in first year science disciplines

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    Student retention and progression rates are a matter of concern for most institutions in the higher education sector (Burton & Dowling, 2005;. Simpson, 2006;. Tinto & Pusser, 2006) in Australia. There is also a substantial body of literature concentrating on the first year experience at university (for example, in the Australian context, see Krause, Hartley, James, McInnis, & Centre for the Study of Higher Education. University of Melbourne, 2005). One of the particular concerns is that the diversity of the student body is rapidly increasing. Of course, with diversity comes with differentiated level of preparation for academic study within the student body

    Language difficulties in first year Science

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    A key goal of the study entitled ‘A cross-disciplinary approach to language support for first year students in the science disciplines’, funded by the Carrick Institute for Learning and Teaching in Higher Education, is to examine the role of language in the learning of science by first-year university students. The disciplines involved are Physics, Chemistry and Biology. This national project also aims to transfer active learning skills, which are widely used in language teaching, to the teaching of science in first year. The paper discusses the background to the study, reports on some of the preliminary results on the language difficulties faced by first year student cohorts in science from data collected in 2008, and describes the framework we have established for the organization and delivery of first year science courses to be implemented in semester one 2009

    Embedding in-discipline language support for first year students in the sciences

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    This paper reports on a project which aims at addressing the need to cater for the language needs of a diverse student body (both domestic and international student body) by embedding strategic approaches to learning and teaching in first year sciences in tertiary education. These strategies consist of active learning skills which are widely used in language learning. The disciplines covered by the project are Biology, Chemistry and Physics and involves the University of Canberra (UC), University of Sydney (USyd), University of Tasmania (UTAS), University of Technology, Sydney (UTS) and University of Newcastle (Newcastle) in Australia. This project is funded by the Australian Learning and Teaching Council (ALTC). The paper discusses the background to the study and reports on results on the language difficulties faced by first year science student cohorts from data collected in 2008 as well as qualitative data was also collected on 2008 students’ attitudes towards online science learning. It will also report on the results on the implementation of the learning strategies at UTS and UTAS in Physics and Chemistry disciplines in 2009. Keywords: First year science teaching, role of language in science teaching, active learning skill

    Visual similarity in masking and priming: The critical role of task relevance

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    Cognitive scientists use rapid image sequences to study both the emergence of conscious perception (visual masking) and the unconscious processes involved in response preparation (masked priming). The present study asked two questions: (1) Does image similarity influence masking and priming in the same way? (2) Are similarity effects in both tasks governed by the extent of feature overlap in the images or only by task-relevant features? Participants in Experiment 1 classified human faces using a single dimension even though the faces varied in three dimensions (emotion, race, sex). Abstract geometric shapes and colors were tested in the same way in Experiment 2. Results showed that similarity reduced the visibility of the target in the masking task and increased response speed in the priming task, pointing to a double-dissociation between the two tasks. Results also showed that only task-relevant (not objective) similarity influenced masking and priming, implying that both tasks are influenced from the beginning by intentions of the participant. These findings are interpreted within the framework of a reentrant theory of visual perception. They imply that intentions can influence object formation prior to the separation of vision for perception and vision for action

    Illusory perceptions of space and time preserve cross-saccadic perceptual continuity

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    When voluntary saccadic eye movements are made to a silently ticking clock, observers sometimes think that the second hand takes longer than normal to move to its next position. For a short period, the clock appears to have stopped (chronostasis). Here we show that the illusion occurs because the brain extends the percept of the saccadic target backwards in time to just before the onset of the saccade. This occurs every time we move the eyes but it is only perceived when an external time reference alerts us to the phenomenon. The illusion does not seem to depend on the shift of spatial attention that accompanies the saccade. However, if the target is moved unpredictably during the saccade, breaking perception of the target's spatial continuity, then the illusion disappears. We suggest that temporal extension of the target's percept is one of the mechanisms that 'fill in' the perceptual 'gap' during saccadic suppression. The effect is critically linked to perceptual mechanisms that identify a target's spatial stability
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