Development of a new versatile computer controlled electrochemical/ESR data acquisition system

A new versatile computer controlled electrochemlcal/ESR data acquisition system has been developed for the Investigation of short-lived radicals with life-times of 20 milliseconds and greater, Different computer programs have been developed to monitor the decay of radicals; over hours or minutes, seconds or milliseconds. Signal averaging and Fourier smoothing is employed in order to improve the signal to noise ratio. Two microcomputers are used to control the system, one home-made computer containing the M6800 chip which controls the magnetic field, and an IBM PC XT which controls the electrochemistry and the data acquisition. The computer programs are written in Fortran and C, and call machine language subroutines, The system functions by having the radical generated by an electrochemical pulse: after or during the pulse the ESR data are collected. Decaying radicals which have half-lives of seconds or greater have their spectra collected in the magnetic field domain, which can be swept as fast as 200 Gauss per second. The decay of the radicals in the millisecond region is monitored by time-resolved ESR: a technique in which data is collected in both the time domain and in the magnetic field domain. Previously, time-resolved ESR has been used (without field modulation) to investigate ultra-short-lived species with life-times in the region of only a few microseconds. The application of the data acquisition system to chemical systems is illustrated. This is the first time a computer controlled system whereby the radical is generated by electrochemical means and subsequently the ESR data collected, has been developed.

A performance testing framework for digital forensic tools

This thesis surveys the latest development of digital forensic tools designed for anti-cybercrime purposes. It discusses the necessity of testing the digital forensics tools, and presents a novel testing framework. This new testing framework takes the viewpoint of software vendors rather than traditional software engineering approaches.

Automatic detection of lung nodule from computer tomography images

Lung nodule refers to lung tissue abnormalities that may become cancerous. An automated system that detects nodules of common sizes within lung images is developed. It consists of acquisition, pre-processing, background removal, nodule detection, and false positives reduction. The system can assist expert radiologists in their decision making.

Computer-assisted image analysis of liver collagen: relationship to Ishak scoring and hepatic venous pressure gradient

Histopathological scoring of disease stage uses descriptive categories without measuring the amount of fibrosis. Collagen, the major component of fibrous tissue, can be quantified by computer-assisted digital image analysis (DIA) using histological sections. We determined relationships between DIA, Ishak stage, and hepatic venous pressure gradient (HVPG) reflecting severity of fibrosis. One hundred fifteen patients with hepatitis C virus (HCV) who had undergone transplantation had 250 consecutive transjugular liver biopsies combined with HVPG (median length, 22 mm; median total portal tracts, 12), evaluated using the Ishak system and stained with Sirus red for DIA. Liver collagen was expressed as collagen proportionate area (CPA). Median CPA was 6% (0.2-45), correlating with Ishak stage (stage 6 range, 13%-45%), and with HVPG (r = 0.62; P < 0.001). Median CPA was 4.1% when HVPG was less than 6 mm Hg and 13.8% when HVPG was 6 mm Hg or more (P < 0.0001) and 6% when HVPG was less than 10 mm Hg and 17.3% when HVPG was 10 mm Hg or higher (P < 0.0001). Only CPA, not Ishak stage/grade, was independently associated by logistic regression, with HVPG of 6 mm Hg or more [odds ratio, 1.206; 95% confidence interval (CI), 1.094-1.331; P < 0.001], or HVPG of 10 mm Hg or more (odds ratio, 1.105; 95% CI, 1.026-1.191; P = 0.009). CPA increased by 50% (3.6%) compared with 20% in HVPG (1 mm Hg) in 38 patients with repeated biopsies. Conclusion: CPA assessed by DIA correlated with Ishak stage scores and HVPG measured contemporaneously. CPA was a better histological correlate with HVPG than Ishak stage, had a greater numerical change when HVPG was low, and resulted in further quantitation of fibrosis in cirrhosis.

Early breast cancer identification : Which way to go? Microarray or image based computer aided diagnosis!

The goal of this research is to develop a computer aided diagnostic (CAD) system that can detect breast cancer in the early stage by using microarray and image data. We verified the performance of six well known classification algorithms with various performance matrices. Although we do not suggest a unique classifier algorithm for a CAD system, we do identify a number of algorithms whose performance is very promising. The algorithms performance was validated by 3 images dataset; two have been used for the first time in this experiment. Multidimensional image filtering is adopted for the final data extraction. The image data classification performance is compared with microarray data. Results suggest the most effective means of breast cancer identification in the early stage is a hybrid approach.

Creating digital divas-scaffolding perception change through secondary school and university alliances

Over the last 20 years much has been done to encourage female students to choose computing courses and computing careers. Some instances of positive effects have been reported, yet the proportional disparity in gender in this discipline continues to grow. This paper reports on a program called 'Digital Divas'. Digital Divas aims to scaffold positive perceptions around computing in the early years of secondary school by involving female students in upbeat computing experiences over a semester. It introduces university undergraduates to the secondary classroom to provide informal role models and mentors, as well as interactions with young computing professionals. This classroom environment enables computer applications to be more strongly linked with future careers. The commitment to a semester length unit was influential in changing perceptions about girls and computing, and the program was supported by the wider school community. We posit that this type of curriculum intervention is needed and has the potential to build technical human capital in female students.

Building equitable literate futures : home and school computer-mediated literacy practices and disadvantage

This paper examines the complex connections between literacy practices, the use of information and communication technologies (ICTs) and disadvantage. It reports the findings of a year-long study which investigated the ways in which four families use ICTs to engage with formal and informal literacy learning in home and school settings. The research set out to explore what it is about computer-mediated literacy practices at home and at school in disadvantaged communities that make a difference in school success. The findings demonstrate that the 'socialisation' of the technology - its appropriation into existing family norms, values and lifestyles - varied from family to family. Having access to ICTs at home was not sufficient for the young people and their families to overcome the so-called 'digital divide'. Clearly, we are seeing shifts in the meaning of 'disadvantage' in a globalised world mediated by the use of new technologies. New definitions of disadvantage that take account not only of access to the new technologies but also include calibrated understandings of what constitutes the access are required. The article concludes that old inequalities have not disappeared, but are playing out in new ways in the context of the networked society.

Building equitable literate futures : home and school computer-mediated literacy practices and disadvantage

This article examines the complex connections between literacy practices, the use of information and communication technologies (ICTs) and disadvantage. It reports the findings of a year-long study which investigated the ways in which four families use ICTs to engage with formal and informal literacy learning in home and school settings. The research set out to explore what it is about computer-mediated literacy practices at home and at school in disadvantaged communities that makes a difference in school success. The findings demonstrate that the 'socialisation' of the technology--its appropriation into existing family norms, values and lifestyles--varied from family to family. Having access to ICTs at home was not sufficient for the young people and their families to overcome the so-called 'digital divide'. The article concludes that old inequalities have not disappeared, but are playing out in new ways in the context of the networked society.

Evaluation framework underpinning the digital divas programme

In Australia, as elsewhere, women’s participation rates in Information Technology (IT) have been low. IT is the generic term used to refer to the many courses in the Computer Science, and Information Systems disciplines. While there have been a number of intervention programmes implemented aimed at encouraging women into IT and retaining them once there, few have included evaluations of the efficacy of the intervention. Thus little is known about the factors contributing to the success, or lack of success, of the interventions, or of the medium and longer term impacts for the participants. In this paper we briefly describe an intervention programme implemented with girls in the high school years. We present an evaluation framework providing a detailed overview of the aims and processes involved in the evaluation of the programme. Data for the evaluation were embedded within the data gathering methods associated with the research on the intervention itself.

Zebra fingerprints : towards a computer-aided identification system for individual zebra

Information regarding wildlife behavioural patterns provides researchers with clearer understanding of species. Social interactions, breeding habits, feeding and migration trends are key factors influencing decisions in game management and ecological impact assessment. In order to obtain such information researchers must be able to track individual animals over a period of time. One of the commonest methods of identifying individual animals is to tag them with radio, satellite, or GPS transmitters (Mech & Barber, 2002). While these systems are very effective, they are often costly and can be traumatic for tagged animals.

Digital natives? New and old media and children's outcomes.

The current generation of young children has been described as 'digital natives', having been born into a ubiquitous digital media environment. They are envisaged as educationally independent of the guided interaction provided by 'digital immigrants': parents and teachers. This article uses data from the Longitudinal Study of Australian Children (LSAC) to study the development of vocabulary and traditional literacy in children aged from 0 to 8 years; their access to digital devices; parental mediation practices; children's use of digital devices as recorded in time-diaries; and, finally, the association between patterns of media use and family contexts on children's learning. The analysis shows the importance of the parental context in framing media use for acquiring vocabulary, and suggests that computer (but not games) use is associated with more developed language skills. Independently of these factors, raw exposure to television is not harmful to learning.

Researching kids and computer games : games, game play and literacy in the twenty first century

Videogames, and young people's engagement with them, are of growing interest to education. This paper reports on initial find ings from the study: Literacy in the Digital World of the Twenty First Century: Leaming from computer games, focussing on the opportunities offered by studying young people's immersion in game play for understanding more about contemporary forms of  engagement and textuality, new forms of literacy,community and identity multimodality, and the implications of such forms and changes for contemporary literacy and English education. Taking videogames as examples of global, ICT-based popular culture, where meaning is built from muhimodal elements, and where young players have to he actively teaming and involved in order to play, the project asks how English and literacy education might benefit from examining videogames, as rich exemplars of contemporary digital culture, and the ways in which young people make use of them, to improve the teaching of print and multi modal forms of literacy.

The "strugglers" in selected computer based mathematics classrooms

In this paper, the experiences of lower achieving mathematics students in two secondary mathematics classrooms in which computers were regularly used are described. A year 8 and a year 9 mathematics class from one secondary school participated in the ethnographic study. The results show that in these two classrooms the learning relationships and power relationships did not, in general, support the learning and engagement of lower achievers in mathematics. Research into computer based teaching methods that engage low achieving students in computer based mathematics is needed.

Image source detection : a case study on Facebook images taken by iPhones

Forged and tempered digital images become increasingly common on Facebook to aid computer frauds. The situation is worsened as many users can use a phone to take a photo and upload it to Facebook within two clicks, which highlights the need of image forensics for the cyber fraud cases. In this paper, we show the existence of the Facebook image filter which automatically changes the Facebook photos and consequently challenges the validity of forensic results. We aim to enable forensic investigators to relate a seized camera and a Facebook image. Specifically, we utilize intrinsic sensor pattern noise produced by a camera's lens to derive forensically useful information as Photo Response Non-Uniformity (PRNU) patterns. We propose to compare the PRNU patterns of a Facebook image and the flat field images produced by the candidate cameras. And we conclude this method to be effective by successfully identifying the correct iPhone from a list of four for a given Face book image.

Preschoolers' physical activity, screen time, and compliance with recommendations

Purpose: Little evidence exists about the prevalence of adequate levels of physical activity and of appropriate screen-based entertainment in preschool children. Previous studies have generally relied on small samples. This study investigates how much time preschool children spend being physically active and engaged in screen-based entertainment. The study also reports compliance with the recently released Australian recommendations for physical activity (>=3 h·d-1) and screen entertainment (<=1 h·d-1) and the National Association for Sport and Physical Education physical activity guidelines (>=2 h·d-1) and American Academy of Pediatrics screen-based entertainment recommendations (<=2 h·d-1) in a large sample of preschool children.

Methods: Participants were 1004 Melbourne preschool children (mean age = 4.5 yr, range = 3–5 yr) and their families in the Healthy Active Preschool Years study. Physical activity data were collected by accelerometry during an 8-d period. Parents reported their child’s television/video/DVD viewing, computer/Internet, and electronic game use during a typical week. A total of 703 (70%) had sufficient accelerometry data, and 935 children (93%) had useable data on time spent in screen-based entertainment.

Results: Children spent 16% (approximately 127 min·d-1) of their time being physically active. Boys and younger children were more active than were girls and older children, respectively. Children spent an average of 113 min·d-1 in screen-based entertainment. Virtually no children (<1%) met both the Australian recommendations and 32% met both the National Association for Sport and Physical Education and American Academy of Pediatrics recommendations.

Conclusions: The majority of young children are not participating in adequate amounts of physical activity and in excessive amounts of screen-based entertainment. It is likely that physical activity may decline and that screen-based entertainment may increase with age. Compliance with recommendations may be further reduced. Strategies to promote physical activity and reduce screen-based entertainment in young children are required.