Search

E-learning systems generally rely on good visual and cognitive abilities, making them suitable for individuals with good levels of intelligence in these areas. A group of such individuals are those with non-systemising impairments (NSIs), such as people with autism spectrum conditions (ASCs). These individuals could benefit greatly from technology that allows them to use their abilities to overcome their impairments in social and emotional functioning in order to develop pro-social behaviours. Existing systems such as PARLE and MindReading are discussed, and a new one, the Visual Ontological Imitation System (VOIS), is proposed and discussed. This chapter details an investigation into the acceptability of these systems by those working in social work and advocacy. The study found that VOIS would be well received, although dependency on assistive technology and its impact on how others view NSIs still need to be addressed by society and its institutions.

Arterial spin labeling is a versatile perfusion quantification methodology, which has the potential to provide accurate characterization of cerebral blood flow (CBF) in mouse models. However, a paucity of physiological data needed for accurate modeling, more stringent requirements for gradient performance, and strong artifacts introduced by magnetization transfer present special challenges for accurate CBF mapping in the mouse. This article describes robust mapping of CBF over three-dimensional brain regions using amplitude-modulated continuous arterial spin labeling. To provide physiological data for CBF modeling, the carotid artery blood velocity distribution was characterized using pulsed-wave Doppler ultrasound. These blood velocity measurements were used in simulations that optimize inversion efficiency for parameters meeting MRI gradient duty cycle constraints. A rapid slice positioning algorithm was developed and evaluated to provide accurate positioning of the labeling plane. To account for enhancement of T(1) due to magnetization transfer, a binary spin bath model of magnetization transfer was used to provide a more accurate estimate of CBF. Finally, a study of CBF was conducted on 10 mice with findings of highly reproducible inversion efficiency (mean ± standard-error-of-the-mean, 0.67 ± 0.03), statistically significant variation in CBF over 12 brain regions (P0.0001) and a mean ± standard-error-of-the-mean whole brain CBF of 219 ± 6 mL/100 g/min.

Knowledge it could be argued is constructed from the information actors pick up from the environments they are in. Assessing this knowledge can be problematic in ubiquitous e-learning systems, but a method of supporting the critical marking of e-learning exercises is the Circle of Friends social networking technology. Understanding the networks of practice in which these e-learning systems are part of requires a deeper understanding of information science frameworks. The Ecological Cognition Framework (ECF) provides a thorough understanding of how actors respond to and influence their environment. Forerunners to ecological cognition, such as activity theory have suggested that the computer is just a tool that mediates between the actor and the physical environment. Utilising the ECF it can be seen that for an e-learning system to be an effective teacher it needs to be able to create five effects in the actors that use it, with those being the belonging effect, the demonstration effect, the inspiration effect, the mobilisation effect, and the confirmation effect. In designing the system a developer would have to consider who the system is going to teach, what it is going to teach, why it is teaching, which techniques it is going to use to teach and finally whether it has been successful. This chapter proposes a multi-agent e-learning system called the Portable Assistant for Intelligently Guided Education (PAIGE), which is based around a 3D anthropomorphic avatar for educating actors ubiquitously. An investigation into the market for PAIGE was carried out. The data showed that those that thought their peers were the best form of support were less likely to spend more of their free time on homework. The chapter suggests that future research could investigate the usage of systems like PAIGE in educational settings and the effect they have on learning outcomes.

The rise of online communities in Internet environments has set in motion an unprecedented shift in power from vendors of goods and services to the customers who buy them, with those vendors who understand this transfer of power and choose to capitalize on it by organizing online communities and being richly rewarded with both peerless customer loyalty and impressive economic returns. A type of online community, the virtual world, could radically alter the way people work, learn, grow consume, and entertain. Understanding the exchange of social and economic capital in online communities could involve looking at what causes actors to spend their resources on improving someone else’s reputation. Actors’ reputations may affect others’ willingness to trade with them or give them gifts. Investigating online communities reveals a large number of different characters and associated avatars. When an actor looks at another’s avatar they will evaluate them and make decisions that are crucial to creating interaction between customers and vendors in virtual worlds based on the exchange of goods and services. This chapter utilizes the ecological cognition framework to understand transactions, characters and avatars in virtual worlds and investigates the exchange of capital in a bulletin board and virtual. The chapter finds strong evidence for the existence of characters and stereotypes based on the ecological cognition framework and empirical evidence that actors using avatars with antisocial connotations are more likely to have a lower return on investment and be rated less positively than those with more sophisticated appearing avatars.

Online dating is a big business, allowing people from the comfort of their own home to view and read about potential mates all around the world. Different dating sites offer different services. However, it is not yet commonplace for Web sites dedicated to dating to use the social networking tools used by popular online communities, such as those that use the personal homepage and message board genres. The ecological cognition framework (ECF) provides a theoretical model regarding online dating communities’ behavior and relationship development. A model based on the ECF is proposed and provides a basis for developing online dating services that effectively support relationship development. Two investigations are presented in this chapter, one that uses a case study approach to identify and describe online dating services from the perspective of a specific case and another that assess the effectiveness of existing online dating services based on the guidelines developed from the case study. The case study provides a useful insight into the nature of social networking from the perspective of a specific case, which led to guidelines for developing e-dating systems that when evaluated showed that the most popular social networking services also score well against the criteria proposed in those guidelines.

Fast spin-echo (FSE) sequences are becoming popular for T2-weighted clinical imaging because they result in a severalfold reduction in imaging time and because they provide conventional spin-echo contrast for most tissues. Fat, however, has been observed to have anomalously high signal intensity on FSE images. The present study shows that the brighter fat results from the multiple 180 degrees refocusing pulses, which eliminate diffusion-mediated susceptibility dephasing and suppress J-coupling modulation of the echo train.

A new pulse sequence that increases the number of sections that can be acquired with a T2-weighted multisection imaging prescription is presented. The sequence achieves a higher efficiency in section acquisition per unit time by interleaving excitation and data collection for up to three separate sections during the long TE (greater than or equal to 80 msec) of a T2-weighted spin-echo pulse sequence. The necessary modifications of the section-select and readout gradient waveforms for the implementation of TE-interleaved (TEI) sequences, with and without flow compensation, are described. Secondary- and stimulated-echo artifacts are present on some TEI images, but these can be controlled with appropriate spoiler gradients. The signal-to-noise ratio for contiguous sections is slightly reduced compared with that of a standard multisection pulse sequence. These observations indicate that the effects of radio-frequency section interference are enhanced by the TEI sequence.

Mouse models are crucial for the study of genetic factors and processes that influence human disease. In addition to tools for measuring genetic expression and establishing genotype, tools to accurately and comparatively assess mouse phenotype are essential in order to characterize pathology and make comparisons with human disease. MRI provides a powerful means of evaluating various anatomical and functional changes and hence is growing in popularity as a phenotypic readout for biomedical research studies. To accommodate the large numbers of mice needed in most biological studies, mouse MRI must offer high-throughput image acquisition and efficient image analysis. This article reviews the technology of multiple-mouse MRI, a method that images multiple mice or specimens simultaneously as a means of enabling high-throughput studies. Aspects of image acquisition and computational analysis in multiple-mouse studies are also described. Copyright © 2007 John Wiley & Sons, Ltd.

Over the past decade, several methods have been proposed to image tissue elasticity based on imaging methods collectively called elastography. While progress in developing these systems has been rapid, the basic understanding of tissue properties to interpret elastography images is generally lacking. To address this limitation, we developed a system to measure the Young's modulus of small soft tissue specimens. This system was designed to accommodate biological soft tissue constraints such as sample size, geometry imperfection and heterogeneity. The measurement technique consists of indenting an unconfined small block of tissue while measuring the resulting force. We show that the measured force-displacement slope of such a geometry can be transformed to the tissue Young's modulus via a conversion factor related to the sample's geometry and boundary conditions using finite element analysis. We also demonstrate another measurement technique for tissue elasticity based on quasi-static magnetic resonance elastography in which a tissue specimen encased in a gelatine-agarose block undergoes cyclical compression with resulting displacements measured using a phase contrast MRI technique. The tissue Young's modulus is then reconstructed from the measured displacements using an inversion technique. Finally, preliminary elasticity measurement results of various breast tissues are presented and discussed.

Anatomic measures of injury burden provide key information for studies of prehospital and in-hospital trauma care. The military version of the Abbreviated Injury Scale [AIS(M)] is used to score injuries in deployed military hospitals. Estimates of total trauma burden are derived from this. These scores are used for categorization of patients, assessment of care quality, and research studies. Scoring is normally performed retrospectively from chart review. We compared data recorded in the UK Joint Theatre Trauma Registry (JTTR) and scores calculated independently at the time of surgery by the operating surgeons to assess the concordance between surgeons and trauma nurse coordinators in assigning injury severity scores.Trauma casualties treated at a deployed Role 3 hospital were assigned AIS(M) scores by surgeons between 24 September 2012 and 16 October 2012. JTTR records from the same period were retrieved. The AIS(M), Injury Severity Score (ISS), and New Injury Severity Score (NISS) were compared between datasets.Among 32 matched casualties, 214 injuries were recorded in the JTTR, whereas surgeons noted 212. Percentage agreement for number of injuries was 19%. Surgeons scored 75 injuries as "serious" or greater compared with 68 in the JTTR. Percentage agreement for the maximum AIS(M), ISS, and NISS assigned to cases was 66%, 34%, and 28%, respectively, although the distributions of scores were not statistically different (median ISS: surgeons: 20 [interquartile range (IQR), 9-28] versus JTTR: 17.5 [IQR, 9-31.5], p = .7; median NISS: surgeons: 27 [IQR, 12-42] versus JTTR: 25.5 [IQR, 11.5-41], p = .7).There are discrepancies in the recording of AIS(M) between surgeons directly involved in the care of trauma casualties and trauma nurse coordinators working by retrospective chart review. Increased accuracy might be achieved by actively collaborating in this process.

A reconstruction technique for breast tissue elasticity modulus is described. This technique assumes that the geometry of normal and suspicious tissues is available from a contrast-enhanced magnetic resonance image. Furthermore, it is assumed that the modulus is constant throughout each tissue volume. The technique, which uses quasi-static strain data, is iterative where each iteration involves modulus updating followed by stress calculation. Breast mechanical stimulation is assumed to be done by two compressional rigid plates. As a result, stress is calculated using the finite element method based on the well-controlled boundary conditions of the compression plates. Using the calculated stress and the measured strain, modulus updating is done element-by-element based on Hooke's law. Breast tissue modulus reconstruction using simulated data and phantom modulus reconstruction using experimental data indicate that the technique is robust.

A quasistatic magnetic resonance elastography (MRE) method for the evaluation of breast cancer is proposed. Using a phase contrast, stimulated echo MRI approach, strain imaging in phantoms and volunteers is presented. First-order assessment of tissue biomechanical properties based on inverse strain mapping is outlined and demonstrated. The accuracy of inverse strain imaging is studied through simulations in a two-dimensional model and in an anthropomorphic, three-dimensional finite-element model of the breast. To improve the accuracy of modulus assessment by elastography, inverse methods are discussed as an extension to strain imaging, and simulations quantify MRE in terms of displacement signal/noise required for robust inversion. A direct inversion strategy providing information on tissue modulus and pressure distribution is described along with a novel iterative method utilizing a priori knowledge of tissue geometry. It is shown that through the judicious choice of information from previous contrast-enhanced MRI breast images, MRE data acquisition requirements can be significantly reduced while maintaining robust modulus reconstruction in the presence of strain noise. An experimental apparatus for clinical breast MRE and preliminary images of a normal volunteer are presented.

Increasing numbers of adolescents are being diagnosed with Crohn's disease or ulcerative colitis, the two main subtypes of inflammatory bowel disease. These young people face many short- and long-term challenges; one or more medical therapies may be required indefinitely; their disease may have great impact, in terms of their schooling and social activities. However, the management of adolescents with one of these incurable conditions needs to encompass more than just medical therapies. Growth, pubertal development, schooling, transition, adherence, and psychological well-being are all important aspects. A multidisciplinary team setting, catering to these components of care, is required to ensure optimal outcomes in adolescents with inflammatory bowel disease.

Three-dimensional (3D) keyhole magnetic resonance (MR) imaging has been proposed as a means of providing dynamic monitoring of contrast agent uptake by breast lesions, with complete breast coverage and high spatial and temporal resolution. The 3D keyhole technique dynamically samples the central regions of k-space in both phase-encoding directions and provides high-frequency data from a precon-trast acquisition. Errors due to data truncation with two-dimensional and 3D region-of-lnterest measurements are estimated from a numerical simulation of various implementations of the 3D keyhole technique. Errors were found to increase with increasing temporal resolution and reduced object size. Errors of 75% are possible for objects with a diameter approaching 1 pixel when a 3D keyhole implementation that samples 50% of phase-encoding data in each direction is used. Preliminary clinical Images with this approach illustrate artifacts consistent with inadequate k-space sampling.

Careful attention to the regular pattern of contrasting parable with explanation, mystery with interpretation, and crowd with disciples allows the careful reader to gain new insight into the scope and purpose of Mark's enterprise as a whole.

Background Genetic polymorphisms, gender and age all influence the risk of developing chronic neuropathic pain following peripheral nerve injury (PNI). It is known that there are significant inter-strain differences in pain hypersensitivity in strains of mice after PNI. In response to PNI, one of the earliest events is thought to be the disruption of the blood-spinal cord barrier (BSCB). The study of BSCB integrity after PNI may lead to a better understanding of the mechanisms that contribute to chronic pain. Results Here we used in vivo dynamic contrast-enhanced magnetic resonance imaging (DCE-MRI) to establish a timecourse for BSCB permeability following PNI, produced by performing a spared nerve injury (SNI). From this longitudinal study, we found that the SNI group had a significant increase in BSCB permeability over time throughout the entire spinal cord. The BSCB opening had a delayed onset and the increase in permeability was transient, returning to control levels just over one day after the surgery. We also examined inter-strain differences in BSCB permeability using five mouse strains (B10, C57BL/6J, CD-1, A/J and BALB/c) that spanned the range of pain hypersensitivity. We found a significant increase in BSCB permeability in the SNI group that was dependent on strain but that did not correlate with the reported strain differences in PNI-induced tactile hypersensitivity. These results were consistent with a previous experiment using Evans Blue dye to independently assess the status of the BSCB permeability. Conclusions DCE-MRI provides a sensitive and non-invasive method to follow BSCB permeability in the same group of mice over time. Examining differences between mouse strains, we demonstrated that there is an important genetically-based control of the PNI-induced increase in BSCB permeability and that the critical genetic determinants of BSCB opening after PNI are distinct from those that determine genetic variability in PNI-induced pain hypersensitivity. Electronic supplementary material The online version of this article (doi:10.1186/1744-8069-10-60) contains supplementary material, which is available to authorized users.