Coal seam gas waters - their geochemical signature and potential environmental implications

Coal Seam Gas (CSG) is a form of natural gas (mainly methane) sorbed in underground coal beds. To mine this gas, wells are drilled directly into an underground coal seam and groundwater (CSG water) is pumped out to the surface. This lowers the downhole piezometric pressure and enables gas desporption from the coal matrix. In the United States, this gas has been extracted commercially since the 1980s. The economic success of US CSG projects has inspired exploration and development in Australia and New Zealand. In Australia, Queensland’s Bowen and Surat basins have been the subject of increased CSG development over the last decade. CSG growth in other Australian basins has not matured to the same level but exploration and development are taking place at an accelerated pace in the Sydney Basin (Illawarra and the Hunter Valley, NSW) and in the Gunnedah Basin. Similarly, CSG exploration in New Zealand has focused in the Waikato region (Maramarua and Huntly), in the West Coast region (Buller, Reefton, and Greymouth), and in Southland (Kaitangata, Mataura, and Ohai). Figure 1 shows a Shcoeller diagram with CSG samples from selected basins in Australia, New Zealand, and the USA. CSG water from all of these basins exhibit the same geochemical signature – low calcium, low magnesium, high bicarbonate, low sulphate and, sometimes, high chloride. This water quality is a direct result of specific biological and geological processes that have taken part in the formation of CSG. In general, these processes include the weathering of rocks (carbonates, dolomite, and halite), cation exchange with clays (responsible for enhanced sodium and depleted calcium and magnesium), and biogenic processes (accounting for the presence of high bicarbonate concentrations). The salinity of CSG waters tends to be brackish (TDS < 30000 mg/l) with a fairly neutral pH. These particular characteristics need to be taken into consideration when assessing water management and disposal alternatives. Environmental issues associated with CSG water disposal have been prominent in developed basins such as the Powder River Basin (PRB) in the United States. When disposed on the land or used for irrigation, water having a high dissolved salts content may reduce water availability to crops thus affecting crop yield. In addition, the high sodium, low calcium and low magnesium concentrations increase the potential to disperse soils and significantly reduce the water infiltration rate. Therefore, CSG waters need to be properly characterised, treated, and disposed to safeguard the environment without compromising other natural resources.

Generation and characterisation of Cisplatin-resistant non-small cell lung cancer cell lines displaying a stem-like signature

Introduction: Inherent and acquired cisplatin resistance reduces the effectiveness of this agent in the management of non-small cell lung cancer (NSCLC). Understanding the molecular mechanisms underlying this process may result in the development of novel agents to enhance the sensitivity of cisplatin. Methods: An isogenic model of cisplatin resistance was generated in a panel of NSCLC cell lines (A549, SKMES-1, MOR, H460). Over a period of twelve months, cisplatin resistant (CisR) cell lines were derived from original, age-matched parent cells (PT) and subsequently characterized. Proliferation (MTT) and clonogenic survival assays (crystal violet) were carried out between PT and CisR cells. Cellular response to cisplatin-induced apoptosis and cell cycle distribution were examined by FACS analysis. A panel of cancer stem cell and pluripotent markers was examined in addition to the EMT proteins, c-Met and β-catenin. Cisplatin-DNA adduct formation, DNA damage (γH2AX) and cellular platinum uptake (ICP-MS) was also assessed. Results: Characterisation studies demonstrated a decreased proliferative capacity of lung tumour cells in response to cisplatin, increased resistance to cisplatin-induced cell death, accumulation of resistant cells in the G0/G1 phase of the cell cycle and enhanced clonogenic survival ability. Moreover, resistant cells displayed a putative stem-like signature with increased expression of CD133+/CD44+cells and increased ALDH activity relative to their corresponding parental cells. The stem cell markers, Nanog, Oct-4 and SOX-2, were significantly upregulated as were the EMT markers, c-Met and β-catenin. While resistant sublines demonstrated decreased uptake of cisplatin in response to treatment, reduced cisplatin-GpG DNA adduct formation and significantly decreased γH2AX foci were observed compared to parental cell lines. Conclusion: Our results identified cisplatin resistant subpopulations of NSCLC cells with a putative stem-like signature, providing a further understanding of the cellular events associated with the cisplatin resistance phenotype in lung cancer. © 2013 Barr et al.

Threshold concepts in property education : a case study

First year Property Economics students enrolled in the Bachelor of Urban Development at QUT are required to undertake a number of compulsory subjects, alongside students undertaking studies in other disciplines. One such common unit is ‘Stewardship of Land’, an interdisciplinary unit that introduces students to the characteristics of land and land tenure with a focus on land use and property rights. It covers a range of issues including: native title, land contamination, heritage values, alternative uses, the property development process, impact of environmental and social factors, and the management of land, both urban and regional. Teaching such a diverse content to a diverse audience has in previous years proved difficult, from the perspectives of relevance, engagement and content overload. In 2011 a project was undertake to redevelop this unit to reflect ‘threshold concepts’, concepts that are “transformative, probably irreversible, integrative, often troublesome and probably bounded” (Meyer & Land, 2003) . This project involved the development of a new set of underlying concepts students should draw from the unit, application of these to the unit curriculum, and a survey of the student response to these changes. This paper reports on the threshold concepts developed for this unit, the changes this made to the unit curriculum, and a preliminary report on survey responses. Recommendations for other educators seeking to incorporate threshold concepts into their curricula are provided.

The other side of the threshold : Strindberg's experiments in creative dissection

A 1500-word review of Strindberg: A Life by Sue Prideaux (Yale UP, 2012). One way of classifying biographies is to divide them into those that apply their own interpretative framework – be it psychoanalytic, gender-based, socio-historical, and so on – to a given subject and those that aim to meet the subject, on their own terms, or at least in terms that the subject would recognise...

A lightweight biometric signature scheme for user authentication over networks

We introduce a lightweight biometric solution for user authentication over networks using online handwritten signatures. The algorithm proposed is based on a modified Hausdorff distance and has favorable characteristics such as low computational cost and minimal training requirements. Furthermore, we investigate an information theoretic model for capacity and performance analysis for biometric authentication which brings additional theoretical insights to the problem. A fully functional proof-of-concept prototype that relies on commonly available off-the-shelf hardware is developed as a client-server system that supports Web services. Initial experimental results show that the algorithm performs well despite its low computational requirements and is resilient against over-the-shoulder attacks.

Implementing the self-management threshold learning outcome in Australian legal curricula : insights from self-determination theory

In 2010, six Threshold Learning Outcomes (TLOs) for law were developed by the Australian Learning and Teaching Council's Discipline Scholars: Law. The final of these outcomes, TLO 6, concerns self-management. This thesis examines strategies for implementing self-management in Australian legal education by first contextualising the development of TLO 6 in light of other relevant national and international developments in higher education, and secondly, analysing this learning outcome through the lens of Self-Determination Theory (SDT), an influential branch of educational psychology. It is argued that the central concept of autonomous self-regulation in SDT provides insights into factors that are relevant to law students’ capacities for long-term self-management, which is reinforced by analysis of the literature on law students’ distress. Accordingly, curriculum design that supports students’ autonomy may simultaneously promote students’ self-management capacities. The discussion of theoretical and practical perspectives on autonomy supportive curriculum design in this thesis thus illuminates potential pedagogical approaches for the implementation of TLO 6 in Australian legal curricula.

An envirogenomic signature is associated with risk of IBD-related surgery in a population-based Crohn’s Disease cohort

BACKGROUND AND AIMS: Crohn's disease (CD) is an inflammatory bowel disease (IBD) caused by a combination of genetic, clinical, and environmental factors. Identification of CD patients at high risk of requiring surgery may assist clinicians to decide on a top-down or step-up treatment approach. METHODS: We conducted a retrospective case-control analysis of a population-based cohort of 503 CD patients. A regression-based data reduction approach was used to systematically analyse 63 genomic, clinical and environmental factors for association with IBD-related surgery as the primary outcome variable. RESULTS: A multi-factor model was identified that yielded the highest predictive accuracy for need for surgery. The factors included in the model were the NOD2 genotype (OR = 1.607, P = 2.3 × 10(-5)), having ever had perianal disease (OR = 2.847, P = 4 × 10(-6)), being post-diagnosis smokers (OR = 6.312, P = 7.4 × 10(-3)), being an ex-smoker at diagnosis (OR = 2.405, P = 1.1 × 10(-3)) and age (OR = 1.012, P = 4.4 × 10(-3)). Diagnostic testing for this multi-factor model produced an area under the curve of 0.681 (P = 1 × 10(-4)) and an odds ratio of 3.169, (95 % CI P = 1 × 10(-4)) which was higher than any factor considered independently. CONCLUSIONS: The results of this study require validation in other populations but represent a step forward in the development of more accurate prognostic tests for clinicians to prescribe the most optimal treatment approach for complicated CD patients.

Outcomes of the Chemistry Discipline Network Mapping Exercises: Are the Threshold Learning Outcomes met?

The Chemistry Discipline Network has recently completed two distinct mapping exercises. The first is a snapshot of chemistry taught at 12 institutions around Australia in 2011. There were many similarities but also important differences in the content taught and assessed at different institutions. There were also significant differences in delivery, particularly laboratory contact hours, as well as forms and weightings of assessment. The second mapping exercise mapped the chemistry degrees at three institutions to the Threshold Learning Outcomes for chemistry. Importantly, some of the TLOs were addressed by multiple units at all institutions, while others were not met, or were met at an introductory level only. The exercise also exposed some challenges in using the TLOs as currently written.

Acquiring search expertise : learning experiences and threshold concepts

Expert searchers engage with information as information brokers, researchers, reference librarians, information architects, faculty who teach advanced search, and in a variety of other information-intensive professions. Their experiences are characterized by a profound understanding of information concepts and skills and they have an agile ability to apply this knowledge to interacting with and having an impact on the information environment. This study explored the learning experiences of searchers to understand the acquisition of search expertise. The research question was: What can be learned about becoming an expert searcher from the learning experiences of proficient novice searchers and highly experienced searchers? The key objectives were: (1) to explore the existence of threshold concepts in search expertise; (2) to improve our understanding of how search expertise is acquired and how novice searchers, intent on becoming experts, can learn to search in more expertlike ways. The participant sample drew from two population groups: (1) highly experienced searchers with a minimum of 20 years of relevant professional experience, including LIS faculty who teach advanced search, information brokers, and search engine developers (11 subjects); and (2) MLIS students who had completed coursework in information retrieval and online searching and demonstrated exceptional ability (9 subjects). Using these two groups allowed a nuanced understanding of the experience of learning to search in expertlike ways, with data from those who search at a very high level as well as those who may be actively developing expertise. The study used semi-structured interviews, search tasks with think-aloud narratives, and talk-after protocols. Searches were screen-captured with simultaneous audio-recording of the think-aloud narrative. Data were coded and analyzed using NVivo9 and manually. Grounded theory allowed categories and themes to emerge from the data. Categories represented conceptual knowledge and attributes of expert searchers. In accord with grounded theory method, once theoretical saturation was achieved, during the final stage of analysis the data were viewed through lenses of existing theoretical frameworks. For this study, threshold concept theory (Meyer & Land, 2003) was used to explore which concepts might be threshold concepts. Threshold concepts have been used to explore transformative learning portals in subjects ranging from economics to mathematics. A threshold concept has five defining characteristics: transformative (causing a shift in perception), irreversible (unlikely to be forgotten), integrative (unifying separate concepts), troublesome (initially counter-intuitive), and may be bounded. Themes that emerged provided evidence of four concepts which had the characteristics of threshold concepts. These were: information environment: the total information environment is perceived and understood; information structures: content, index structures, and retrieval algorithms are understood; information vocabularies: fluency in search behaviors related to language, including natural language, controlled vocabulary, and finesse using proximity, truncation, and other language-based tools. The fourth threshold concept was concept fusion, the integration of the other three threshold concepts and further defined by three properties: visioning (anticipating next moves), being light on one's 'search feet' (dancing property), and profound ontological shift (identity as searcher). In addition to the threshold concepts, findings were reported that were not concept-based, including praxes and traits of expert searchers. A model of search expertise is proposed with the four threshold concepts at its core that also integrates the traits and praxes elicited from the study, attributes which are likewise long recognized in LIS research as present in professional searchers. The research provides a deeper understanding of the transformative learning experiences involved in the acquisition of search expertise. It adds to our understanding of search expertise in the context of today's information environment and has implications for teaching advanced search, for research more broadly within library and information science, and for methodologies used to explore threshold concepts.

Learning portals : analyzing threshold concept theory for LIS education

This paper explores the theoretical framework of threshold concepts and its potential for LIS education. Threshold concepts are key ideas, often troublesome and counter-intuitive, that are critical to profound understanding of a domain. Once understood, they allow mastery of significant aspects of the domain, opening up new, previously inaccessible ways of thinking. The paper is developed in three parts. First, threshold concept theory is introduced and studies of its use in higher education are described, including emergent work related to LIS. Second, results of a recent study on learning experiences integral to learning to search are presented along with their implications for search expertise and search education, forming a case illustration of what threshold concept theory may contribute to this and other areas of LIS education. Third, the potential of threshold concept theory for LIS education is discussed. The paper concludes that threshold concept theory has much to offer LIS education, particularly for researching critical concepts and competencies, and considerations for a research agenda are put forth.

Understanding the signature pedagogy of the design studio and the opportunities for its technological enhancement

This paper presents an analysis of the studio as the signature pedagogy of design education. A number of theoretical models of learning, pedagogy, and education are used to interrogate the studio for its advantages and shortcomings, and to identify opportunities for the integration of new technologies and to explore the affordances that they might offer. In particular the theoretical ideas of signature pedagogies, conversational frameworks, and pedagogical patterns are used to justify the ‘unique’ status of the studio as a dominant learning environment and mode of delivery within design education. Such analysis identifies the opportunities for technological intervention and enhancement of the design studio through a re-examining of its fundamental pedagogical signature. This paper maps the dimensions and qualities that define the signature pedagogy against a range of delivery modes and technological media forms. Through such investigation it seeks to identify appropriate opportunities for technology; in essence offering a structure or framework for the analysis of future enquiry and experimentation.

The potential of combining phenomenography, variation theory and threshold concepts to inform curriculum design in higher education

This chapter describes an innovative method of curriculum design that is based on combining phenomenographic research, and the associated variation theory of learning, with the notion of disciplinary threshold concepts to focus specialised design attention on the most significant and difficult parts of the curriculum. The method involves three primary stages: (i) identification of disciplinary concepts worthy of intensive curriculum design attention, using the criteria for threshold concepts; (ii) action research into variation in students’ understandings/misunderstandings of those concepts, using phenomenography as the research approach; (iii) design of learning activities to address the poorer understandings identified in the second stage, using variation theory as a guiding framework. The curriculum design method is inherently theory and evidence based. It was developed and trialed during a two-year project funded by the Australian Learning and Teaching Council, using physics and law disciplines as case studies. Disciplinary teachers’ perceptions of the impact of the method on their teaching and understanding of student learning were profound. Attempts to measure the impact on student learning were less conclusive; teachers often unintentionally deviated from the design when putting it into practice for the first time. Suggestions for improved implementation of the method are discussed.

Practical Modbus flooding attack and detection

The Modicon Communication Bus (Modbus) protocol is one of the most commonly used protocols in industrial control systems. Modbus was not designed to provide security. This paper confirms that the Modbus protocol is vulnerable to flooding attacks. These attacks involve injection of commands that result in disrupting the normal operation of the control system. This paper describes a set of experiments that shows that an anomaly-based change detection algorithm and signature-based Snort threshold module are capable of detecting Modbus flooding attacks. In comparing these intrusion detection techniques, we find that the signature-based detection requires a carefully selected threshold value, and that the anomaly-based change detection algorithm may have a short delay before detecting the attacks depending on the parameters used. In addition, we also generate a network traffic dataset of flooding attacks on the Modbus control system protocol.

Adapting Lyubashevsky's signature schemes to the ring signature setting

Basing signature schemes on strong lattice problems has been a long standing open issue. Today, two families of lattice-based signature schemes are known: the ones based on the hash-and-sign construction of Gentry et al.; and Lyubashevsky’s schemes, which are based on the Fiat-Shamir framework. In this paper we show for the first time how to adapt the schemes of Lyubashevsky to the ring signature setting. In particular we transform the scheme of ASIACRYPT 2009 into a ring signature scheme that provides strong properties of security under the random oracle model. Anonymity is ensured in the sense that signatures of different users are within negligible statistical distance even under full key exposure. In fact, the scheme satisfies a notion which is stronger than the classical full key exposure setting as even if the keypair of the signing user is adversarially chosen, the statistical distance between signatures of different users remains negligible. Considering unforgeability, the best lattice-based ring signature schemes provide either unforgeability against arbitrary chosen subring attacks or insider corruption in log-sized rings. In this paper we present two variants of our scheme. In the basic one, unforgeability is ensured in those two settings. Increasing signature and key sizes by a factor k (typically 80 − 100), we provide a variant in which unforgeability is ensured against insider corruption attacks for arbitrary rings. The technique used is pretty general and can be adapted to other existing schemes.