Subacute effects of ecstasy on mood : an exploration of associated risk factors

Ecstasy use may result in lowered mood, anxiety or aggression in the days following use. Yet, few studies have investigated what factors increase the risk of experiencing such symptoms. Ecstasy users (at least once in the last 12 months) who subsequently took ecstasy (n=35) over the next week, were compared on measures of mood, sleep, stress and drug use, with those who abstained (n=21) that week. Measures were administered the week prior to ecstasy use and 1 and 3 days following use, or the equivalent day for abstainers. Mood symptoms were assessed using the Kessler-10 self-report psychological distress scale, a subjective mood rating (1-10), and the depression, anxiety and hostility items of the clinician-rated Brief Psychiatric Rating Scale. Timeline followback methods were used to collect information on drug use and life stress in the past month. Self-reported sleep quality was also assessed. Ecstasy use was not associated with subacute depressive, anxiety or aggressive symptoms. Rather, lowered mood and increased psychological distress were associated with self-reported hours and quality of sleep obtained during the 3-day follow up. These findings highlight the importance of considering sleep disruption in understanding the short-term mood effects of ecstasy use.

Ultimate limit states design of concrete railway sleepers

The railway industry has been slow to adopt limit states principles in the structural design of concrete sleepers for its tracks, despite the global take up of this form of design for almost every other type of structural element. Concrete sleeper design is still based on limiting stresses but is widely perceived by track engineers to lead to untapped reserves of strength in the sleepers. Limit design is a more rational philosophy, especially where it is based on the ultimate dynamic capacity of the concrete sleepers. The paper describes the development of equations and factors for a limit design methodology for concrete sleepers in flexure using a probabilistic evaluation of sleeper loading. The new method will also permit a cogent, defensible means of establishing the true capacity of the billions of concrete sleepers that are currently in-track around the world, leading to better utilisation of track infrastructure. The paper demonstrates how significant cost savings may be achieved by track owners.

Atmospheric deposition as a source of heavy metals in urban stormwater

Atmospheric deposition is one of the most important pathways of urban stormwater pollution. Atmospheric deposition which can be in the form of either wet or dry deposition have distinct characteristics in terms of associated particulate sizes, pollutant types and influential parameters. This paper discusses the outcomes of a comprehensive research study undertaken to identify important traffic characteristics and climate factors such as antecedent dry period and rainfall characteristics which influences the characteristics of wet and dry deposition of solids and heavy metals. The outcomes confirmed that Zinc (Zn) is correlated with traffic volume whereas Lead (Pb), Cadmium (Cd), Nickel (Ni), and Copper (Cu) are correlated with traffic congestion. Consequently, reducing traffic congestion will be more effective than reducing traffic volume for improving air quality particularly in relation to Pb, Cd, Ni, and Cu. Zn was found to have the highest atmospheric deposition rate compared to other heavy metals. Zn in dry deposition is associated with relatively larger particle size fractions (>10 µm), whereas Pb, Cd, Ni and Cu are associated with relatively smaller particle size fractions (<10 µm). The analysis further revealed that bulk (wet plus dry) deposition which is correlated with rainfall depth and contains a relatively higher percentage of smaller particles compared to dry deposition which is correlated with the antecedent dry period. As particles subjected to wet deposition are smaller, they disperse over a larger area from the source of origin compared to particles subjected to dry deposition as buoyancy forces become dominant for smaller particles compared to the influence of gravity. Furthermore, exhaust emission particles were found to be primarily associated with bulk deposition compared to dry deposition particles which mainly originate from vehicle component wear.

Influence of Rainfall and Catchment Characteristics on Urban Stormwater Quality

The accuracy and reliability of urban stormwater quality modelling outcomes are important for stormwater management decision making. The commonly adopted approach where only a limited number of factors are used to predict urban stormwater quality may not adequately represent the complexity of the quality response to a rainfall event or site-to-site differences to support efficient treatment design. This paper discusses an investigation into the influence of rainfall and catchment characteristics on urban stormwater quality in order to investigate the potential areas for errors in current stormwater quality modelling practices. It was found that the influence of rainfall characteristics on pollutant wash-off is step-wise based on specific thresholds. This means that a modelling approach where the wash-off process is predicted as a continuous function of rainfall intensity and duration is not appropriate. Additionally, other than conventional catchment characteristics, namely, land use and impervious surface fraction, other catchment characteristics such as impervious area layout, urban form and site specific characteristics have an important influence on both, pollutant build-up and wash-off processes. Finally, the use of solids as a surrogate to estimate other pollutant species was found to be inappropriate. Individually considering build-up and wash-off processes for each pollutant species should be the preferred option.

Cross-entropy optimization for scaling factors of a fuzzy controller : a see-and-avoid approach for unmanned aerial systems

The Cross-Entropy (CE) is an efficient method for the estimation of rare-event probabilities and combinatorial optimization. This work presents a novel approach of the CE for optimization of a Soft-Computing controller. A Fuzzy controller was designed to command an unmanned aerial system (UAS) for avoiding collision task. The only sensor used to accomplish this task was a forward camera. The CE is used to reach a near-optimal controller by modifying the scaling factors of the controller inputs. The optimization was realized using the ROS-Gazebo simulation system. In order to evaluate the optimization a big amount of tests were carried out with a real quadcopter.

Factors affecting two- and five-year re-offence rates in Queensland drink drivers

Risk factors for repeat drink driving, an important road safety issue, are well known, but estimates of Australian recidivism rates by risk factors, apart from a recent NSW study, are not. Driving records of a cohort of Queensland drink drivers matched by age, region, BAC level and prior offence to participants in a drink driving rehabilitation program were used to estimate sex-specific two- and five-year re-offence rates overall and by these factors. Estimates of the proportion of Queensland drink drivers with a prior DD offence in 2004 were used to standardise rates to the Queensland drink driving population. Rates were higher in remote areas, as were rates in males, young drivers, drivers with high BAC levels and in drivers with one and especially with at least two prior DD convictions. Five-year rates for Queensland were estimated as 21.8% in males and 16.4% in females, appreciably higher than in NSW.

Thinking about Australia and its location in the modern world in the Australian Curriculum : history

The first national history curriculum is being implemented in Australia from 2013. As with the curriculums of other nations, this curriculum has evolved in response to a range of factors and its merits continue to be debated. In critiquing the sort of history education approach encapsulated in the new curriculum, I discuss some of the contextual factors and debates that have shaped the Australian Curriculum: History v0.3 (ACARA, 2012). In doing so, I also explore some of the recent international literature on how students think and learn about history in the classroom. In the third and final part of the paper, I raise some logistical issues and also question how students might engage with the notion of Australia as a nation in the modern world rapidly reshaped by the transformations occurring in Asia and share some concerns about the curriculum’s ‘world history approach’ for Year 10.

What makes an LMS effective : a synthesis of current literature

There is a growing number of organizations and universities now utilising e-learning practices in their teaching and learning programs. These systems have allowed for knowledge sharing and provide opportunities for users to have access to learning materials regardless of time and place. However, while the uptake of these systems is quite high, there is little research into the effectiveness of such systems, particularly in higher education. This paper investigates the methods that are used to study the effectiveness of e-learning systems and the factors that are critical for the success of a learning management system (LMS). Five major success categories are identified in this study and explained in depth. These are the teacher, student, LMS design, learning materials and external support.

Mediating identity narratives : a case study in queer digital storytelling as everyday activism

Digital Stories are short autobiographical documentaries, often illustrated with personal photographs and narrated in the first person, and typically produced in group workshops. As a media form they offer ‘ordinary people’ the opportunity to represent themselves to audiences of their choosing; and this amplification of hitherto unheard voices has significant repercussions for their social participation. Many of the storytellers involved in the ‘Rainbow Family Tree’ case study that is the subject of this paper can be characterised as ‘everyday’ activists for their common desire to use their personal stories to increase social acceptance of marginalised identity categories. However, in conflict with their willingness to share their personal stories, many fear the risks and ramifications of distributing them in public spaces (especially online) to audiences both intimate and unknown. Additionally, while technologies for production and distribution of rich media products have become more accessible and user-friendly, many obstacles remain. For many people there are difficulties with technological access and aptitude, personal agency, cultural capital, and social isolation, not to mention availability of the time and energy requisite to Digital Storytelling. Additionally, workshop context, facilitation and distribution processes all influence the content of stories. This paper explores the many factors that make ‘authentic’ self-representation far from straight forward. I use qualitative data drawn from interviews, Digital Story texts and ethnographic observation of GLBTQIS participants in a Digital Storytelling initiative that combined face-to-face and online modes of participation. I consider mediating influences in practice and theory and draw on strategies put forth in cultural anthropology and narrative therapy to propose some practical tools for nuanced and sensitive facilitation of Digital Storytelling workshops and webspaces. Finally, I consider the implications of these facilitation strategies for voice, identity and social participation.

Adaptive radiotherapy for virally mediated head and neck cancer : predicting which patients may benefit most

Background: Recent clinical studies have demonstrated an emerging subgroup of head and neck cancers that are virally mediated. This disease appears to be a distinct clinical entity with patients presenting younger and with more advanced nodal disease, having lower tobacco and alcohol exposure and highly radiosensitive tumours. This means they are living longer, often with the debilitating functional side effects of treatment. The primary objective of this study was to determine how virally mediated nasopharyngeal and oropharyngeal cancers respond to radiation therapy treatment. The aim was to determine risk categories and corresponding adaptive treatment management strategies to proactively manage these patients. Method/Results: 121 patients with virally mediated, node positive nasopharyngeal or oropharyngeal cancer who received radiotherapy treatment with curative intent between 2005 and 2010 were studied. Relevant patient demographics including age, gender, diagnosis, TNM stage, pre-treatment nodal size and dose delivered was recorded. Each patient’s treatment plan was reviewed to determine if another computed tomography (re-CT) scan was performed and at what time point (dose/fraction) this occurred. The justification for this re-CT was determined using four categories: tumour and/or nodal regression, weight loss, both or other. Patients who underwent a re-CT were further investigated to determine whether a new plan was calculated. If a re-plan was performed, the dosimetric effect was quantified by comparing dose volume histograms of planning target volumes and critical structures from the actual treatment delivered and the original treatment plan. Preliminary results demonstrated that 25/121 (20.7%) patients required a re-CT and that these re-CTs were performed between fractions 20 to 25 of treatment. The justification for these re-CTs consisted of a combination of tumour and/or nodal regression and weight loss. 16/25 (13.2%) patients had a replan calculated. 9 (7.4%) of these replans were implemented clinically due to the resultant dosimetric effect calculated. The data collected from this assessment was statistically analysed to identify the major determining factors for patients to undergo a re-CT and/or replan. Specific factors identified included nodal size and timing of the required intervention (i.e. how when a plan is to be adapted). This data was used to generate specific risk profiles that will form the basis of a biologically guided adaptive treatment management strategy for virally mediated head and neck cancer. Conclusion: Preliminary data indicates that virally mediated head and neck cancers respond significantly during radiation treatment (tumour and/or nodal regression and weight loss). Implications of this response are the potential underdosing or overdosing of tumour and/or surrounding critical structures. This could lead to sub-optimal patient outcomes and compromised quality of life. Consequently, the development of adaptive treatment strategies that improve organ sparing for this patient group is important to ensure delivery of the prescribed dose to the tumour volume whilst minimizing the dose received to surrounding critical structures. This could reduce side effects and improve overall patient quality of life. The risk profiles and associated adaptive treatment approaches developed in this study will be tested prospectively in the clinical setting in Phase 2 of this investigation.

Factors influencing caregiver : care receiver communication and its impact on the well-being of older care receivers

Examined communication between frail older people and their caregiving spouses (CGSs), and its relation to well-being in older care receivers. 53 community residing spousal dyads completed questionnaires about their well-being, relational satisfaction, and communication patterns. Conversations between the dyads were also videotaped and analyzed. The type of communication used by the CGSs was influenced by their sex, their earlier relationship with their spouse, and their level of well-being. CGSs who used an overly directive communication tone with their spouse were likely to be wives and CGSs who had a high degree of autonomy in their earlier relationship with their spouse. Low levels of life satisfaction and high affect balance in CGSs were associated with CGSs using a more patronizing tone. The well-being of care receivers was also related to their perceptions of their CGSs' communication. Care receivers who perceived their CGSs' communication as patronizing reported low levels of affect balance and high levels of conflict in the relationship. Findings suggest that certain characteristics of CGSs are related to the type of communication they use when conversing with their partner, although the relations are not always as expected.

Asset health prediction using the explicit hazard model

The ability to estimate the asset reliability and the probability of failure is critical to reducing maintenance costs, operation downtime, and safety hazards. Predicting the survival time and the probability of failure in future time is an indispensable requirement in prognostics and asset health management. In traditional reliability models, the lifetime of an asset is estimated using failure event data, alone; however, statistically sufficient failure event data are often difficult to attain in real-life situations due to poor data management, effective preventive maintenance, and the small population of identical assets in use. Condition indicators and operating environment indicators are two types of covariate data that are normally obtained in addition to failure event and suspended data. These data contain significant information about the state and health of an asset. Condition indicators reflect the level of degradation of assets while operating environment indicators accelerate or decelerate the lifetime of assets. When these data are available, an alternative approach to the traditional reliability analysis is the modelling of condition indicators and operating environment indicators and their failure-generating mechanisms using a covariate-based hazard model. The literature review indicates that a number of covariate-based hazard models have been developed. All of these existing covariate-based hazard models were developed based on the principle theory of the Proportional Hazard Model (PHM). However, most of these models have not attracted much attention in the field of machinery prognostics. Moreover, due to the prominence of PHM, attempts at developing alternative models, to some extent, have been stifled, although a number of alternative models to PHM have been suggested. The existing covariate-based hazard models neglect to fully utilise three types of asset health information (including failure event data (i.e. observed and/or suspended), condition data, and operating environment data) into a model to have more effective hazard and reliability predictions. In addition, current research shows that condition indicators and operating environment indicators have different characteristics and they are non-homogeneous covariate data. Condition indicators act as response variables (or dependent variables) whereas operating environment indicators act as explanatory variables (or independent variables). However, these non-homogenous covariate data were modelled in the same way for hazard prediction in the existing covariate-based hazard models. The related and yet more imperative question is how both of these indicators should be effectively modelled and integrated into the covariate-based hazard model. This work presents a new approach for addressing the aforementioned challenges. The new covariate-based hazard model, which termed as Explicit Hazard Model (EHM), explicitly and effectively incorporates all three available asset health information into the modelling of hazard and reliability predictions and also drives the relationship between actual asset health and condition measurements as well as operating environment measurements. The theoretical development of the model and its parameter estimation method are demonstrated in this work. EHM assumes that the baseline hazard is a function of the both time and condition indicators. Condition indicators provide information about the health condition of an asset; therefore they update and reform the baseline hazard of EHM according to the health state of asset at given time t. Some examples of condition indicators are the vibration of rotating machinery, the level of metal particles in engine oil analysis, and wear in a component, to name but a few. Operating environment indicators in this model are failure accelerators and/or decelerators that are included in the covariate function of EHM and may increase or decrease the value of the hazard from the baseline hazard. These indicators caused by the environment in which an asset operates, and that have not been explicitly identified by the condition indicators (e.g. Loads, environmental stresses, and other dynamically changing environment factors). While the effects of operating environment indicators could be nought in EHM; condition indicators could emerge because these indicators are observed and measured as long as an asset is operational and survived. EHM has several advantages over the existing covariate-based hazard models. One is this model utilises three different sources of asset health data (i.e. population characteristics, condition indicators, and operating environment indicators) to effectively predict hazard and reliability. Another is that EHM explicitly investigates the relationship between condition and operating environment indicators associated with the hazard of an asset. Furthermore, the proportionality assumption, which most of the covariate-based hazard models suffer from it, does not exist in EHM. According to the sample size of failure/suspension times, EHM is extended into two forms: semi-parametric and non-parametric. The semi-parametric EHM assumes a specified lifetime distribution (i.e. Weibull distribution) in the form of the baseline hazard. However, for more industry applications, due to sparse failure event data of assets, the analysis of such data often involves complex distributional shapes about which little is known. Therefore, to avoid the restrictive assumption of the semi-parametric EHM about assuming a specified lifetime distribution for failure event histories, the non-parametric EHM, which is a distribution free model, has been developed. The development of EHM into two forms is another merit of the model. A case study was conducted using laboratory experiment data to validate the practicality of the both semi-parametric and non-parametric EHMs. The performance of the newly-developed models is appraised using the comparison amongst the estimated results of these models and the other existing covariate-based hazard models. The comparison results demonstrated that both the semi-parametric and non-parametric EHMs outperform the existing covariate-based hazard models. Future research directions regarding to the new parameter estimation method in the case of time-dependent effects of covariates and missing data, application of EHM in both repairable and non-repairable systems using field data, and a decision support model in which linked to the estimated reliability results, are also identified.

Factors that influence Chinese TEFL academics' research capacity building : an institutional case study

Research capacity building has become a prominent theme in higher education institutions across the world. To build research capacity, it is necessary to identify areas of challenges academics face within the academia. This case study focuses on Chinese teaching English as a foreign language (TEFL) academics with the purpose of identifying factors that influence their research capacity building. Six TEFL academics from a Chinese national university were interviewed and institutional research documents were analysed. Findings showed that obstacles and difficulties in conducting research were more related to departmental factors than individual characteristics. The institution was keen on developing a research culture, and encouraged research and publications. Departmental support for research was improving, but it seems that it was more generic than tailored to individual needs. The findings of this study provide implications for research administrators in further supporting TEFL academics’ research capacity building.

Understanding the participatory library through a grounded theory study

Lankes and Silverstein (2006) introduced the “participatory library” and suggested that the nature and form of the library should be explored. In the last several years, some attempts have been made in order to develop contemporary library models that are often known as Library 2.0. However, little research has been based on empirical data and such models have had a strong focus on technical aspects but less focus on participation. The research presented in this paper fills this gap. A grounded theory approach was adopted for this study. Six librarians were involved in in-depth individual interviews. As a preliminary result, five main factors of the participatory library emerged including technological, human, educational, social-economic, and environmental. Five factors influencing the participation in libraries were also identified: finance, technology, education, awareness, and policy. The study’s findings provide a fresh perspective on contemporary library and create a basis for further studies on this area.

Mutual enlightenment : augmenting human factors research in surgical robotics

This discussion has outlined a theoretical and pragmatic framework to demonstrate that future research involving the analysis of human performance in surgical should encourage the use of phenomenology to enhance the knowledge base of this area of study. Merging experiential (first-person) and experimental (third-person) methods may possibly help improve research designs and analyses in the investigation of robotics in surgical performance. By relying solely on third-person techniques, the current methodology and interpretation used to analyze human performance in surgical robotics is limited. Recent advances in cognitive science and psychology have also recognized this limitation and have now begun to shift to neurophenomenology. Finally, discussion on recent robotics research presented here demonstrates the potential phenomenology holds for augmenting the methodological and analysis techniques currently used by researchers of human performance in surgical robotics.