Understanding the abnormal brain activity in epilepsy as a potential predictor of the onset of an epileptic seizure

The Brain Research Institute (BRI) uses various types of indirect measurements, including EEG and fMRI, to understand and assess brain activity and function. As well as the recovery of generic information about brain function, research also focuses on the utilisation of such data and understanding to study the initiation, dynamics, spread and suppression of epileptic seizures. To assist with the future focussing of this aspect of their research, the BRI asked the MISG 2010 participants to examine how the available EEG and fMRI data and current knowledge about epilepsy should be analysed and interpreted to yield an enhanced understanding about brain activity occurring before, at commencement of, during, and after a seizure. Though the deliberations of the study group were wide ranging in terms of the related matters considered and discussed, considerable progress was made with the following three aspects. (1) The science behind brain activity investigations depends crucially on the quality of the analysis and interpretation of, as well as the recovery of information from, EEG and fMRI measurements. A number of specific methodologies were discussed and formalised, including independent component analysis, principal component analysis, profile monitoring and change point analysis (hidden Markov modelling, time series analysis, discontinuity identification). (2) Even though EEG measurements accurately and very sensitively record the onset of an epileptic event or seizure, they are, from the perspective of understanding the internal initiation and localisation, of limited utility. They only record neuronal activity in the cortical (surface layer) neurons of the brain, which is a direct reflection of the type of electrical activity they have been designed to record. Because fMRI records, through the monitoring of blood flow activity, the location of localised brain activity within the brain, the possibility of combining fMRI measurements with EEG, as a joint inversion activity, was discussed and examined in detail. (3) A major goal for the BRI is to improve understanding about ``when'' (at what time) an epileptic seizure actually commenced before it is identified on an eeg recording, ``where'' the source of this initiation is located in the brain, and ``what'' is the initiator. Because of the general agreement in the literature that, in one way or another, epileptic events and seizures represent abnormal synchronisations of localised and/or global brain activity the modelling of synchronisations was examined in some detail. References C. M. Michel, G. Thut, S. Morand, A. Khateb, A. J. Pegna, R. Grave de Peralta, S. Gonzalez, M. Seeck and T. Landis, Electric source imaging of human brain functions, Brain Res. 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A critical look at cryptographic hash function literature

The cryptographic hash function literature has numerous hash function definitions and hash function requirements, and many of them disagree. This survey talks about the various definitions, and takes steps towards cleaning up the literature by explaining how the field has evolved and accurately depicting the research aims people have today.

Navigating the future of roads – considering potential impacts of environmental and social trends on road infrastructure

Providing mobility corridors for communities, enabling freight networks to transport goods and services, and a pathway for emergency services and disaster relief operations, roads are a vital component of our societal system. In the coming decades, a number of modern issues will face road agencies as a result of climate change, resource scarcity and energy related challenges that will have implications for society. To date, these issues have been discussed on a case by case basis, leading to a fragmented approach by state and federal agencies in considering the future of roads – with potentially significant cost and risk implications. Within this context, this paper summarises part of a research project undertaken within the ‘Greening the Built Environment’ program of the Sustainable Built Environment National Research Centre (SBEnrc, Australia), which identified key factors or ‘trends’ affecting the future of roads and key strategies to ensure that road agencies can continue to deliver road infrastructure that meets societal needs in an environmentally appropriate manner. The research was conducted over two years, including a review of academic and state agency literature, four stakeholder workshops in Western Australia and Queensland, and industry consultation. The project was supported financially and through peer review and contribution, by Main Roads Western Australia, QLD Department of Transport and Main Roads, Parsons Brinckerhoff, John Holland Group, and the Australian Green Infrastructure Council (AGIC). The project highlighted several potential trends that are expected to affect road agencies in the future, including predicted resource and materials shortages, increases in energy and natural resources prices, increased costs related to greenhouse gas emissions, changing use and expectations of roads, and changes in the frequency and intensity of weather events. Exploring the implications of these potential futures, the study then developed a number of strategies in order to prepare transport agencies for the associated risks that such trends may present. An unintended outcome of the project was the development of a process for enquiring into future scenarios, which will be explored further in Stage 2 of the project (2013-2014). The study concluded that regardless of the type and scale of response by the agency, strategies must be holistic in approach, and remain dynamic and flexible.

A Survey of the 2010 Quartz Crystal Microbalance Literature

In 2010 there has again been an increase in the number of papers published involving piezoelectric acoustic sensors, or quartz crystal microbalances (QCM), when compared to the last period reviewed 2006-2009. The average number of QCM publications per annum was 124 in the period 2001-2005, 223 in the period 2006-9, and 273 in 2010. There are trends towards increasing use of QCM in the study of protein adsorption to surfaces (93% increase), homeostasis (67% increase), protein-protein interactions (40% increase), and carbohydrates (43% increase). New commercial systems have been released that are driving the uptake of the technology for characterisation of binding specificities, affinities, kinetics and conformational changes associated with a molecular recognition event. This article highlights theoretical and practical aspects of the principals that underpin acoustic analysis, then reviews exemplary papers in key application areas involving small molecular weight ligands, carbohydrates, proteins, nucleic acids, viruses, bacteria, cells, and membrane interfaces.

The global public health issue of pharmaceutical waste : what role for pharmacists?

Purpose Pharmaceuticals have played an important role in improving the quality of life of the human population in modern times. However, it must also be acknowledged that both the production and use of pharmaceuticals have a significant, negative impact on the environment and consequently, a negative impact on the health of humans and wildlife. This negative impact is due to the embedded carbon in pharmaceuticals' manufacture and distribution and the waste generated in their manufacture, consumption and disposal. Pharmaceutical waste is comprised of contaminated waste (unwanted pharmaceuticals and their original containers) and non-contaminated waste (non-hazardous packaging waste). The paper aims to discuss these issues. Design/methodology/approach The article is a literature review. Findings The article identified a gap in the literature around pharmacist attitudes and behaviour toward the environmentally responsible handling of pharmaceutical waste. Originality/value Pharmacists, with their professional commitment to the quality use of medicines and their active participation in the medicines management pathway, already play an important role in the more sustainable use of pharmaceuticals. Even so, they have the potential to play an even greater role with the environmentally responsible disposal of pharmaceutical waste (including packaging waste) and the education of other health professionals and the general public on this topic.

Irregular readers : Arthur Conan Doyle’s “six dirty scoundrels”, boyhood and literacy in contemporary Sherlockian children’s literature

Young adult (YA) literature is a socialising genre that encourages young readers to take up particular ways of relating to historical or cultural materials. The first decade of the twenty-first century witnessed a boom in Sherlockian YA fiction using the Conan Doyle canon as a context and vocabulary for stories focused on the Baker Street Irregulars as figures of identification. This paper reads YA fiction’s deployment of Conan Doyle’s fictional universe as a strategy for negotiating anxieties of adolescent masculinity, particularly in relation to literacy and social agency.

Time- vs. frequency-domain identification of parametric radiation force models for marine structures at zero speed

The dynamics describing the motion response of a marine structure in waves can be represented within a linear framework by the Cummins Equation. This equation contains a convolution term that represents the component of the radiation forces associated with fluid memory effects. Several methods have been proposed in the literature for the identification of parametric models to approximate and replace this convolution term. This replacement can facilitate the model implementation in simulators and the analysis of motion control designs. Some of the reported identification methods consider the problem in the time domain while other methods consider the problem in the frequency domain. This paper compares the application of these identification methods. The comparison is based not only on the quality of the estimated models, but also on the ease of implementation, ease of use, and the flexibility of the identification method to incorporate prior information related to the model being identified. To illustrate the main points arising from the comparison, a particular example based on the coupled vertical motion of a modern containership vessel is presented.

Hybrid frequency–time domain models for dynamic response analysis of marine structures

Time-domain models of marine structures based on frequency domain data are usually built upon the Cummins equation. This type of model is a vector integro-differential equation which involves convolution terms. These convolution terms are not convenient for analysis and design of motion control systems. In addition, these models are not efficient with respect to simulation time, and ease of implementation in standard simulation packages. For these reasons, different methods have been proposed in the literature as approximate alternative representations of the convolutions. Because the convolution is a linear operation, different approaches can be followed to obtain an approximately equivalent linear system in the form of either transfer function or state-space models. This process involves the use of system identification, and several options are available depending on how the identification problem is posed. This raises the question whether one method is better than the others. This paper therefore has three objectives. The first objective is to revisit some of the methods for replacing the convolutions, which have been reported in different areas of analysis of marine systems: hydrodynamics, wave energy conversion, and motion control systems. The second objective is to compare the different methods in terms of complexity and performance. For this purpose, a model for the response in the vertical plane of a modern containership is considered. The third objective is to describe the implementation of the resulting model in the standard simulation environment Matlab/Simulink.

Damping structure selection in nonlinear ship manoeuvring models

This paper presents the application of a statistical method for model structure selection of lift-drag and viscous damping components in ship manoeuvring models. The damping model is posed as a family of linear stochastic models, which is postulated based on previous work in the literature. Then a nested test of hypothesis problem is considered. The testing reduces to a recursive comparison of two competing models, for which optimal tests in the Neyman sense exist. The method yields a preferred model structure and its initial parameter estimates. Alternatively, the method can give a reduced set of likely models. Using simulated data we study how the selection method performs when there is both uncorrelated and correlated noise in the measurements. The first case is related to instrumentation noise, whereas the second case is related to spurious wave-induced motion often present during sea trials. We then consider the model structure selection of a modern high-speed trimaran ferry from full scale trial data.

Discerning the timing and cause of historical mortality events in modern Porites from the Great Barrier Reef

The life history strategies of massive Porites corals make them a valuable resource not only as key providers of reef structure, but also as recorders of past environmental change. Yet recent documented evidence of an unprecedented increase in the frequency of mortality in Porites warrants investigation into the history of mortality and associated drivers. To achieve this, both an accurate chronology and an understanding of the life history strategies of Porites are necessary. Sixty-two individual Uranium–Thorium (U–Th) dates from 50 dead massive Porites colonies from the central inshore region of the Great Barrier Reef (GBR) revealed the timing of mortality to have occurred predominantly over two main periods from 1989.2 ± 4.1 to 2001.4 ± 4.1, and from 2006.4 ± 1.8 to 2008.4 ± 2.2 A.D., with a small number of colonies dating earlier. Overall, the peak ages of mortality are significantly correlated with maximum sea-surface temperature anomalies. Despite potential sampling bias, the frequency of mortality increased dramatically post-1980. These observations are similar to the results reported for the Southern South China Sea. High resolution measurements of Sr/Ca and Mg/Ca obtained from a well preserved sample that died in 1994.6 ± 2.3 revealed that the time of death occurred at the peak of sea surface temperatures (SST) during the austral summer. In contrast, Sr/Ca and Mg/Ca analysis in two colonies dated to 2006.9 ± 3.0 and 2008.3 ± 2.0, suggest that both died after the austral winter. An increase in Sr/Ca ratios and the presence of low Mg-calcite cements (as determined by SEM and elemental ratio analysis) in one of the colonies was attributed to stressful conditions that may have persisted for some time prior to mortality. For both colonies, however, the timing of mortality coincides with the 4th and 6th largest flood events reported for the Burdekin River in the past 60 years, implying that factors associated with terrestrial runoff may have been responsible for mortality. Our results show that a combination of U–Th and elemental ratio geochemistry can potentially be used to precisely and accurately determine the timing and season of mortality in modern massive Porites corals. For reefs where long-term monitoring data are absent, the ability to reconstruct historical events in coral communities may prove useful to reef managers by providing some baseline knowledge on disturbance history and associated drivers.

Knowledge Based Urban Development

The changing and challenging conditions of the 21st century have been significantly impacting our economy, society and built and natural environments. Today generation of knowledge—mostly in the form of technology and innovation—is seen as a panacea for the adaptation to changes and management of challenges (Yigitcanlar, 2010a). Making space and place that concentrate on knowledge generation, thus, has become a priority for many nations (van Winden, 2010). Along with this movement, concepts like knowledge cities and knowledge precincts are coined as places where citizenship undertakes a deliberate and systematic initiative for founding its development on the identification and sustainable balance of its shared value system, and bases its ability to create wealth on its capacity to generate and leverage its knowledge capabilities (Carrillo, 2006; Yigitcanlar, 2008a). In recent years, the term knowledge precinct (Hu & Chang, 2005) in its most contemporary interpretation evolved into knowledge community precinct (KCP). KCP is a mixed-use post-modern urban setting—e.g., flexible, decontextualized, enclaved, fragmented—including a critical mass of knowledge enterprises and advanced networked infrastructures, developed with the aim of collecting the benefits of blurring the boundaries of living, shopping, recreation and working facilities of knowledge workers and their families. KCPs are the critical building blocks of knowledge cities, and thus, building successful KCPs significantly contributes to the formation of prosperous knowledge cities. In the literature this type of development—a place containing economic prosperity, environmental sustainability, just socio‐spatial order and good governance—is referred as knowledge-based urban development (KBUD). This chapter aims to provide a conceptual understanding on KBUD and its contribution to the building of KCPs that supports the formation of prosperous knowledge cities.

Can physical activity prevent physical and cognitive decline in postmenopausal women? A systematic review of the literature

Background Participation in regular physical activity is among the most promising and cost effective strategies to reduce physical and cognitive decline and premature death. However, confusion remains about the amount, frequency, and duration of physical activity that is likely to provide maximum benefit as well as the way in which interventions should be delivered. Aims This paper aimed to review research on the impact of leisure-time and general physical activity levels on physical and cognitive decline in postmenopausal women. In a systematic review of the literature, empirical literature from 2009-2013 is reviewed to explore the potential impact of either commencing or sustaining physical activity on older women’s health. Results All studies found that physical activity was associated with lower rates of cognitive and physical decline and a significant reduction in all-cause mortality. In this review we found that exercise interventions (or lifestyle activities) that improved cardiorespiratory exercise capacity showed the most positive impact on physical health. Conclusions Findings suggest that programs should facilitate and support women to participate in regular exercise by embedding physical activity programs in public health initiatives, by developing home-based exercise programs that require few resources and by creating interventions that can incorporate physical activity within a healthy lifestyle. The review also suggests that clinicians should consider prescribing exercise in a tailored manner for older women to ensure that it is of a high enough intensity to obtain the positive sustained effects of exercise.

Diversity or perversity?: Award-winning children's literature and the Australian curriculum

Two of the three cross-curriculum priorities for the national Australian Curriculum prescribed by the Australian Curriculum Assessment and Reporting Authority (ACARA) are focussed on what might be called diversity education: “Aboriginal and Torres Strait Islander histories and culture”, and "Asia and Australia's Engagement with Asia” (ACARA, “Cross”). One need not be versed in complex rhetorical theory to understand that, laudable and legitimate as such priorities are, their existence implies that mainstream education in Australia has been or is characterised by the marginalisation or erasure of Australia's history—the original Indigenous cultures are not only living and vibrant today, but also have tens of thousands of years’ “head start” on Australia’s settler cultures—and of its geography—Australia is, after all, located in some physical proximity to Asia. Some might even suggest that Australia is in Asia. These temporal and spatial “forgettings” constitute a kind of cultural perversity which the cross-curricular priorities both seek to address and serve to reinscribe. Even as ACARA requires Australian school students to engage with Aboriginal and Asian histories, cultures, societies, they imply that such histories, cultures, and societies are “diverse”, that they are not those of the students in Australian classrooms; producing them as objects of study rather than as lived experience. This should not necessarily be surprising. Michael W. Apple has provocatively argued that: “one of the perverse effects of a national curriculum actually will be to ‘legitimise inequality.’ It may in fact help create the illusion that whatever the massive differences in schools, they all have something in common” (18). In the Australian context, attempts to mitigate such perversity are articulated via the selection of literary texts. As educators move to resource ACARA’s cross-curricular priorities, ACARA notes that “Teachers and schools are best placed to make decisions about the selection of texts in their teaching and learning programs that address the content in the Australian Curriculum while also meeting the needs of the students in their classes” (ACARA, “Advice”). This assertion appears on a webpage called “Advice on selection of literary texts” which is notable first and foremost for its total lack of any literary texts being named, and its list of weblinks pointing to lists of texts compiled elsewhere, by other organisations, and in the main, compiled to serve agendas other than the Australian curriculum. One of the major resources referred to by ACARA for literary text selection is the Children’s Book Council of Australia (CBCA). Of course, the CBCA’s annual book awards do not share ACARA’s educational priorities, but do have a history of being drawn upon by schools as a curriculum resource. In this paper, I consider the literary texts which have been prized by the CBCA in recent years attending to their engagements with Aboriginal cultures.

Designing schools as effective 21st C learning spaces : a review

The Queensland Centre for Social Science Innovation was formed in 2012 to develop collaborations among the Queensland Government and five Queensland universities—The University of Queensland, Griffith University, Queensland University of Technology, James Cook University and Central Queensland University. Three priorities for initial projects were established by the Queensland Government with response by the participating universities. This project addressed the identified priority area: factors affecting educational achievement and investigation of the link between school design, refurbishment and educational outcomes. The proposal for this project indicated that a Review of research literature would be undertaken that linked school and classroom design with educational outcomes for learners in the 21st century. Further, research would be examined for impact of technology on staff and students, as well as learning spaces that addressed the diversity of student learners. Specific investigation of research on effective design to enhance learning outcomes for Aboriginal and Torres Strait Islander students was to be undertaken. The project therefore consists of a Review of research literature to provide an evidence base on the impact of school and classroom on educational outcomes. The original proposal indicated that indicators of successful school and classroom design would be student learning outcomes on a range of variables, with input, the specific architectural design elements. The review was undertaken during the period July 2012 to June 2013. A search was undertaken of journals, databases, and websources to identify relevant material. These were examined for evidence-based statements and design of learning spaces to enhance learning. The Review is comprehensive, and representative of issues raised in research, and conceptualisations and debates informing modern educational design. Initial findings indicated two key findings central to reading this Review. The first key finding is that the predominant focus of modern design of learning space is on process and the engagement of stakeholders. Schools are social institutions and development of a school as a learning space to suit 21st century learning needs necessarily involves the staff, students and other members of the community as key participants. The concept of social aspects of design is threaded throughout the Review. The second key finding is that little research explicitly examined the relationship between the design of learning spaces and educational outcomes. While some research does exist, the most explicitly-focused research uses narrow test-based achievement as the learning outcomes. These are not sympathetic to the overall framings of the research on 21st century learning, future schooling and the needs of the new generation of learners and society.