273 research outputs found
Personalised Learning Spaces and Self-Regulated Learning :Global examples of Effective Pedagogy
Recent educational research attests to an increasing awareness of the need to encourage learner control over the entire learning process. Web 2.0 and social software tools are capable of supporting informal conversation, dialogue and collaborative content generation, enabling access to a wide raft of ideas and representations. Used appropriately, they can shift control to the learner by promoting agency, autonomy and engagement in social networks that straddle multiple real and virtual learning spaces independent of physical, geographic, institutional and organisational boundaries. However, in order for selfregulated learning to come to fruition, students need not only to be able to choose and personalise what tools and content are available, but also to have access to appropriate scaffolding to support their learning. Emerging practices with social software, examples of which are showcased in this paper, signal the need for pedagogies that are more social, personal and participatory. The paper concludes with a discussion of the implications for practice, including current challenges faced by tertiary educators
Precision Formation Keeping at L2 Using the Autonomous Formation Flying Sensor
Recent advances in formation keeping for large numbers of spacecraft using the Autonomous Formation Flying are presented. This sensor, currently under development at JPL, has been identified as a key component in future formation flying spacecraft missions. The sensor provides accurate range and bearing measurements between pairs of spacecraft using GPS technology. Previous theoretical work by the authors has focused on developing a decentralized scheduling algorithm to control the tasking of such a sensor between the relative range and bearing measurements to each node in the formation. The resulting algorithm has been modified to include switching constraints in the sensor. This paper also presents a testbed for real time validation of a sixteen-node formation based on the Stellar Imager mission. Key aspects of the simulation include minimum fuel maneuvers based on free-body dynamics and a three body propagator for simulating the formation at L2
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Development and validation of risk score for predicting positive repeat prostate biopsy in patients with a previous negative biopsy in a UK population.
BACKGROUND: Little evidence is available to determine which patients should undergo repeat biopsy after initial benign extended core biopsy (ECB). Attempts have been made to reduce the frequency of negative repeat biopsies using PSA kinetics, density, free-to-total ratios and Kattan's nomogram, to identify men more likely to harbour cancer but no single tool accurately predicts biopsy outcome. The objective of this study was to develop a predictive nomogram to identify men more likely to have a cancer diagnosed on repeat prostate biopsy. METHODS: Patients with previous benign ECB undergoing repeat biopsy were identified from a database. Association between age, volume, stage, previous histology, PSA kinetics and positive repeat biopsy was analysed. Variables were entered stepwise into logistic regression models. A risk score giving the probability of positive repeat biopsy was estimated. The performance of this score was assessed using receiver characteristic (ROC) analysis. RESULTS: 110 repeat biopsies were performed in this period. Cancer was detected in 31% of repeat biopsies at Hospital (1) and 30% at Hospital (2). The most accurate predictive model combined age, PSA, PSA velocity, free-to-total PSA ratio, prostate volume and digital rectal examination (DRE) findings. The risk model performed well in an independent sample, area under the curve (AUCROC) was 0.818 (95% CI 0.707 to 0.929) for the risk model and 0.696 (95% CI 0.472 to 0.921) for the validation model. It was calculated that using a threshold risk score of > 0.2 to identify high risk individuals would reduce repeat biopsies by 39% while identifying 90% of the men with prostate cancer. CONCLUSION: An accurate multi-variable predictive tool to determine the risk of positive repeat prostate biopsy is presented. This can be used by urologists in an outpatient setting to aid decision-making for men with prior benign histology for whom a repeat biopsy is being considered.RIGHTS : This article is licensed under the BioMed Central licence at http://www.biomedcentral.com/about/license which is similar to the 'Creative Commons Attribution Licence'. In brief you may : copy, distribute, and display the work; make derivative works; or make commercial use of the work - under the following conditions: the original author must be given credit; for any reuse or distribution, it must be made clear to others what the license terms of this work are
Effects of depleting ionic strength on 31P nuclear magnetic resonance spectra of micellar casein during membrane separation and diafiltration of skim milk
peer-reviewedMembrane separation processes used in the concentration and isolation of micellar casein-based milk proteins from skim milk rely on extensive permeation of its soluble serum constituents, especially lactose and minerals. Whereas extensive literature exists on how these processes influence the gross composition of milk proteins, we have little understanding of the effects of such ionic depletion on the core structural unit of micellar casein [i.e., the casein phosphate nanocluster (CPN)]. The 31P nuclear magnetic resonance (NMR) is an analytical technique that is capable of identifying soluble and organic forms of phosphate in milk. Thus, our objective was to investigate changes to the 31P NMR spectra of skim milk during microfiltration (MF) and diafiltration (DF) by tracking movements in different species of phosphate. In particular, we examined the peak at 1.11 ppm corresponding to inorganic phosphate in the serum, as well as the low-intensity broad signal between 1.5 and 3.0 ppm attributed to casein-associated phosphate in the retentate. The MF concentration and DF using water caused a shift in the relevant 31P NMR peak that could be minimized if orthophosphate was added to the DF water. However, this did not resolve the simultaneous change in retentate pH and increased solubilization of micellar casein protein. The addition of calcium in combination with orthophosphate prevented micellar casein solubilization and simultaneously contributed to preservation of the CPN structure, except for overcorrection of retentate pH in the acidic direction. A more complex DF solution, involving a combination of phosphate, calcium, and citrate, succeeded in both CPN and micellar casein structure preservation while maintaining retentate pH in the region of the original milk pH. The combination of 31P NMR as an analytical technique and experimental probe during MF/DF processes provided useful insights into changes occurring to CPN while retaining the micellar state of casein
Hyaluronic Acid: Its Versatile Use in Ocular Drug Delivery with a Specific Focus on Hyaluronic Acid-Based Polyelectrolyte Complexes.
Extensive research is currently being conducted into novel ocular drug delivery systems (ODDS) that are capable of surpassing the limitations associated with conventional intraocular anterior and posterior segment treatments. Nanoformulations, including those synthesised from the natural, hydrophilic glycosaminoglycan, hyaluronic acid (HA), have gained significant traction due to their enhanced intraocular permeation, longer retention times, high physiological stability, inherent biocompatibility, and biodegradability. However, conventional nanoformulation preparation methods often require large volumes of organic solvent, chemical cross-linkers, and surfactants, which can pose significant toxicity risks. We present a comprehensive, critical review of the use of HA in the field of ophthalmology and ocular drug delivery, with a discussion of the physicochemical and biological properties of HA that render it a suitable excipient for drug delivery to both the anterior and posterior segments of the eye. The pivotal focus of this review is a discussion of the formation of HA-based nanoparticles via polyelectrolyte complexation, a mild method of preparation driven primarily by electrostatic interaction between opposing polyelectrolytes. To the best of our knowledge, despite the growing number of publications centred around the development of HA-based polyelectrolyte complexes (HA-PECs) for ocular drug delivery, no review articles have been published in this area. This review aims to bridge the identified gap in the literature by (1) reviewing recent advances in the area of HA-PECs for anterior and posterior ODD, (2) describing the mechanism and thermodynamics of polyelectrolyte complexation, and (3) critically evaluating the intrinsic and extrinsic formulation parameters that must be considered when designing HA-PECs for ocular application
Virtual sculpting and 3D printing for young people with disabilities
In this paper, we present the SHIVA project which was designed to provide virtual sculpting tools for young people with complex disabilities, to allow them to engage with artistic and creative activities that they might otherwise never be able to access. Modern 3D printing then allows us to physically build their creations. To achieve this, we combined our expertise in education, accessible technology, user interfaces and geometric modelling. We built a generic accessible graphical user interface (GUI) and a suitable geometric modelling system and used these to produce two prototype modelling exercises. These tools were deployed in a school for students with complex disabilities and are now being used for a variety of educational and developmental purposes. In this paper, we present the project's motivations, approach and implementation details together with initial results, including 3D printed objects designed by young people who have disabilties
Interactions of Cosmic Superstrings
We develop methods by which cosmic superstring interactions can be studied in
detail. These include the reconnection probability and emission of radiation
such as gravitons or small string loops. Loop corrections to these are
discussed, as well as relationships to -strings. These tools should
allow a phenomenological study of string models in anticipation of upcoming
experiments sensitive to cosmic string radiation.Comment: 22 pages, 6 figures; v2: updated reference
Oscillatory neural networks underlying resting-state, attentional control and social cognition task conditions in children with ASD, ADHD and ASD+ADHD
Autism spectrum disorder (ASD) and attention-deficit/hyperactivity disorder (ADHD) are common and impairing neurodevelopmental disorders that frequently co-occur. The neurobiological mechanisms involved in ASD and ADHD are not fully understood. However, alterations in large-scale neural networks have been proposed as core deficits in both ASD and ADHD and may help to disentangle the neurobiological basis of these disorders and their co-occurrence. In this study, we examined similarities and differences in large-scale oscillatory neural networks between boys aged 8-13 years with ASD (n = 19), ADHD (n = 18), ASD + ADHD (n = 29) and typical development (Controls, n = 26). Oscillatory neural networks were computed using graph-theoretical methods from electroencephalographic (EEG) data collected during an eyes-open resting-state and attentional control and social cognition tasks in which we previously reported disorder-specific atypicalities in oscillatory power and event-related potentials (ERPs). We found that children with ASD showed significant hypoconnectivity in large-scale networks during all three task conditions compared to children without ASD. In contrast, children with ADHD showed significant hyperconnectivity in large-scale networks during the attentional control and social cognition tasks, but not during the resting-state, compared to children without ADHD. Children with co-occurring ASD + ADHD did not differ from children with ASD when paired with this group and vice versa when paired with the ADHD group, indicating that these children showed both ASD-like hypoconnectivity and ADHD-like hyperconnectivity. Our findings suggest that ASD and ADHD are associated with distinct alterations in large-scale oscillatory networks, and these atypicalities present together in children with both disorders. These alterations appear to be task-independent in ASD but task-related in ADHD, and may underlie other neurocognitive atypicalities in these disorders. [Abstract copyright: Copyright © 2019 Elsevier Ltd. All rights reserved.
Towards the ATS STEM conceptual framework
This report (Report #5) was written as part of a research project titled, Assessment of Transversal Skills in STEM (ATS STEM). The project is funded by Erasmus+ (Call reference: EACEA/28/2017 - European policy experimentations in the fields of Education and Training, and Youth led by high-level public authorities). The development of the ideas, concepts and understandings presented in this final report is visually synthesised in Towards the ATS STEM Conceptual Framework. Towards the ATS STEM Conceptual Framework aims to inform the classroom practices of integrated STEM education topics and their assessment. Educators can benefit from such a conceptual framework encapsulating the key ideas from the literature and that helps to inform their understanding and subsequent classroom practice
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