A Center-Median Filtering Method for Detection of Temporal Variation in Coronal Images

Events in the solar corona are often widely separated in their timescales, which can allow them to be identified when they would otherwise be confused with emission from other sources in the corona. Methods for cleanly separating such events based on their timescales are thus desirable for research in the field. This paper develops a technique for identifying time-varying signals in solar coronal image sequences which is based on a per-pixel running median filter and an understanding of photon-counting statistics. Example applications to 'EIT Waves' and small-scale dynamics are shown, both using data from the 193 Angstrom channel on AIA. The technique is found to discriminate EIT Waves more cleanly than the running and base difference techniques most commonly used. It is also demonstrated that there is more signal in the data than is commonly appreciated, finding that the waves can be traced to the edge of the AIA field of view when the data are rebinned to increase the signal-to-noise ratio.Comment: 15 pages, 7 Figures, Accepted to Journal of Space Weather and Space Climate; version 2 has slight text changes and updated movie URL

Seven myths about young children and technology

Parents and educators tend to have many questions about young children's play with computers and other technologies at home. They can find it difficult to know what is best for children because these toys and products were not around when they were young. Some will tell you that children have an affinity for technology that will be valuable in their future lives. Others think that children should not be playing with technology when they could be playing outside or reading a book

The home as a technological learning environment: children's early encounters with digital technologies

Today's children are growing up in homes with an ever-growing array of technologies supporting families as they work, play, communicate and learn. How have recent rapid changes to the home as a technological environment influenced what and how preschool children learn? This paper, based on a series of studies of young children's experiences with digital technology at home, identifies key factors - including the structure and layout of the home, family practices, family values and family interactions - which shape the ways in which children: a) learn to use technologies; b) learn about the world via the medium of technologies; c) develop learning dispositions; and d) learn about the role of different technologies in family and community contexts

Children's interactions with interactive toy technology

Abstract Digital toys offer the opportunity to explore software scaffolding through tangible interfaces that are not bound to the desktop computer. This paper describes the empirical work completed by the CACHET (Computers and Children's Electronic Toys) project team investigating young children's use of interactive toy technology. The interactive toys in question are plush and cuddly cartoon characters with embedded sensors that can be squeezed to evoke spoken feedback from the toy. In addition to playing with the toy as it stands, the toy can be linked to a desktop PC with compatible software using a wireless radio connection. Once this connection is made the toy offers hints and tips to the children as they play with the accompanying software games. If the toy is absent, the same hints and tips are available through an on-screen animated icon of the toy's cartoon character. The toys as they stand are not impressive as collaborative learning partners, as their help repertoire is inadequate and even inappropriate. However, the technology has potential: children can master the multiple interfaces of toy and screen and, when the task requires it and the help provided is appropriate, they will both seek and use it. In particular, the cuddly interface experience can offer an advantage and the potential for fun interfaces that might address both the affective and the effective dimensions of learners' interactions

At home with the future : influences on young children's early experiences with digital technologies

Early years curricula encourage practitioners to build on children's home experiences. Research into the kinds of activities that young children engage in at home and considerations of how to link these to their experiences in pre-school settings can therefore make an important contribution to practice. This chapter, which draws on studies investigating young children's home experiences with digital technologies, seeks to identify some of the key factors that influence the nature and extent of these experiences. Although digital divides - reflecting classic social divisions of economic status, gender and ethnicity - have been extensively explored in order to understand the causes of inequalities in access to digital technologies, our research concluded that parental attitudes towards these technologies are more influential than economic disadvantage in determining young children's experiences. To explore this issue in greater detail, we have drawn on the concept of prolepsis, a key influence on parents' interactions with their children deriving from the projection of their memories of their own idealised past into the children's futures (Cole, 1996). Parents' assumptions, values and expectations are influenced by their past experiences, enacted in the present, and are then carried by their children into the future as they move from home to formal education. We argue that prolepsis has powerful explanatory force for understanding the kinds of decisions parents make about activities such as the extent to which children engage in technological play

Near-infrared spectroscopy after high-risk congenital heart surgery in the paediatric intensive care unit

Objective: To establish whether the use of near-infrared spectroscopy is potentially beneficial in high-risk cardiac infants in United Kingdom paediatric intensive care units. Design: A prospective observational pilot study. Setting: An intensive care unit in North West England. Patients: A total of 10 infants after congenital heart surgery, five with biventricular repairs and five with single-ventricle physiology undergoing palliation. Interventions: Cerebral and somatic near-infrared spectroscopy monitoring for 24 hours post-operatively in the intensive care unit. Measurement and main results: Overall, there was no strong correlation between cerebral near-infrared spectroscopy and mixed venous oxygen saturation (r=0.48). At individual time points, the correlation was only strong (r=0.74) 1 hour after admission. The correlation was stronger for the biventricular patients (r=0.68) than single-ventricle infants (r=0.31). A strong inverse correlation was demonstrated between cerebral near-infrared spectroscopy and serum lactate at 3 of the 5 post-operative time points (1, 4, and 12 hours: r=-0.76, -0.72, and -0.69). The correlation was stronger when the cerebral near-infrared spectroscopy was 60%, which was r=-0.50. No correlations could be demonstrated between (average) somatic near-infrared spectroscopy and serum lactate (r=-0.13, n=110) or mixed venous oxygen saturation and serum lactate. There was one infant who suffered a cardiopulmonary arrest, and the cerebral near-infrared spectroscopy showed a consistent 43 minute decline before the event. Conclusions: We found that cerebral near-infrared spectroscopy is potentially beneficial as a non-invasive, continuously displayed value and is feasible to use on cost-constrained (National Health Service) cardiac intensive care units in children following heart surgery

A fragment of the Maltese exodus : child migration to Australia 1953-1965

In March 2009, Maltese Prime Minister Gonzi unveiled a memorial to child migration in Grand Harbour. The wording to the monument notes that there were 310 such migrants. It records respect for the achievements of these migrants, joy at their successes and regret at any unintended consequences of child migration. It is evident from letters to the press at the time and from other sources that many in Malta had little knowledge of such migration, and that others did not understand the concept of ‘child migration’. This paper seeks to correct these deficiencies. In doing so it is broken into a number of sections. The next section locates the Maltese experience within the contours of British child migration and to this end provides an historical overview. Section 3 explores the push and pull factors resulting in the commencement of Maltese child migration in 1953. Section 4 provides details of the mechanics of child migration and Section 5 reflects on the child migrant experience. The final section is by way of summary and conclusionpeer-reviewe

Narrative evolution: Learning from students' talk about species variation

Learners do not always enjoy productive interactions with Multimedia Interactive Learning Environments. Their attention can be distracted away from the educational focus intended by designers and teachers through poor design and operational inadequacy. In this paper we describe a study of groups of learners using a multimedia CD-ROM research tool called Galapagos. This tool was developed to enable us to observe groups of learners interacting with different versions of the same multimedia content. These different versions implemented different forms of guidance for learners both within the presented narrative structure of the material and in the tools offered to learners to help them build the individual content elements into a coherent whole. Our empirical work was conducted with groups of learners within their educational establishment using the Galapagos CD-ROM as part of their studies for national examinations in Biology. Their sessions with Galapagos were recorded using video and audio and our analysis of their dialogue has enabled us to gain a greater understanding of the factors that contribute to productive, educationally focused learning interactions. Through the construction of different representations we have been able to coordinate information about interactivity between learners and system at the interface with interactivity between individual learners within the group around the system interface. Varying the quantity and quality of guidance impacts upon the trajectory learners construct through multimedia content; it also influences the manner in which they use the facilities provided by system designers to assist them in their construction of task answers

Learning from the children : exploring preschool children's encounters with ICT at home

This paper is an account of our attempts to understand preschool children's experiences with information and communication technologies (ICT) at home. Using case study data, we focus on what we can learn from talking directly to the children that might otherwise have been overlooked and on describing and evaluating the methods we adopted to ensure that we maximised the children's contributions to the research. By paying attention to the children's perspectives we have learned that they are discriminating users of ICT who evaluate their own performances, know what gives them pleasure and who differentiate between operational competence and the substantive activities made possible by ICT

Affordances for learning in a non-linear narrative medium

A multimedia CD makes an impressive resource for the scholar-researcher, but students unfamiliar with the subject-matter may not always work so effectively with such a resource. Without any narrative structure, how does the novice cope? The paper describes how we are investigating the design features that 'afford' activities that generate learning: What are the design features that encourage students to practise the role of the scholar? What encourages them to explore, but also to reflect on their analysis of the data they find? What kind of learning takes place when students are allowed to explore at will? The paper goes on to compare the learning experiences of students using commercial CDs with those using material with contrasting designs, in an attempt to identify the design features that afford constructive learning activities. It concludes with an interpretation of the findings, comparing them with work in related educational media, and situating the findings in the context of a conversational framework for learning