Fuzzy logic for decision support in chronic care

Computerized clinical guidelines can provide significant benefits in terms of health outcomes and costs, however, their effective computer implementation presents significant problems. Vagueness and ambiguity inherent in natural language (textual) clinical guidelines makes them problematic for formulating automated alerts or advice. Fuzzy logic allows us to formalize the treatment of vagueness in a decision support architecture. In care plan on-line (CPOL), an intranet-based chronic disease care planning system for general practitioners (GPs) in use in South Australia, we formally treat fuzziness in interpretation of quantitative data, formulation of recommendations and unequal importance of clinical indicators. We use expert judgment on cases, as well as direct estimates by experts, to optimize aggregation operators and treat heterogeneous combinations of conjunction and disjunction that are present in the natural language decision rules formulated by specialist teams.r />r />r />

Communication network analysis of the enterprise grid systems

This paper addresses the problem of performance analysis based on communication modelling of largescale heterogeneous distributed systems with emphases on enterprise grid computing systems. The study of communication layers is important because the overall performance of a distributed system is often critically hinged on the effectiveness of this part. This model considers processor as well as network heterogeneity of target system. The model is validated through comprehensive simulation, which demonstrates that the proposed model exhibits a good degree of accuracy for various system sizes and under different working conditions. The proposed model is then used to investigate the performance analysis of typical systems.r />r />

Benchmarking ventricular arrhythmias in the mouse—revisiting the ‘Lambeth Conventions’ 20 years on

The isolated Langendorff-mode perfused heart has become a valuable experimental model, used extensively to examine cardiac function, pathophysiology and pharmacology. For the clinical cardiologist an ECG is often a simple practicality, however in experimental circumstances, particularly with ex vivo murine hearts it is not always possible to obtain an ECG due to experimental recording constraints. However, the mechanical record of ventricular contractile function can be highly informative in relation to electrical state. It is difficult though to achieve consistency in these evaluations of arrhythmia as a validated common reference framework is lacking. In 1988, a group of investigators developed the ‘Lambeth Conventions’—a standardised reference for the definition and classification of arrhythmias in animal experimental models of ischaemia, infarction and reperfusion in vivo. Now, two decades later it is timely to revisit the Lambeth Conventions, and to update the guidelines in the context of the marked increase in murine heart study in experimental cardiac pathophysiology. Here we describe an adjunct to the Lambeth Conventions for the reporting of ventricular arrhythmias post-ischaemia in ex vivo mouse hearts when ECG recordings are not employed. Of seven discrete and identifiable patterns of mechanical dysrhythmia observed in reperfusion, five could be classified using conventional ECG terminology: ventricular premature beat, bigeminy, trigeminy, ventricular tachycardia and ventricular fibrillation. Two additional rhythm variations detected from the pressure record are described (potentiated contraction and alternans).r />

Intrinsic resistance of female hearts to an ischemic insult is abrogated in primary cardiac hypertrophy

Important sex differences in cardiovascular disease outcomes exist, including conditions of hypertrophic cardiomyopathy and cardiac ischemia. Studies of sex differences in the extent to which load-independent (primary) hypertrophy modulates the response to ischemia-reperfusion (I/R) damage have not been characterized. We have previously described a model of primary genetic cardiac hypertrophy, the hypertrophic heart rat (HHR). In this study the sex differences in HHR cardiac function and responses to I/R [compared to control normal heart rat (NHR)] were investigated ex vivo. The ventricular weight index was markedly increased in HHR female (7.82 ± 0.49 vs. 4.80 ± 0.10 mg/g; P < 0.05) and male (5.76 ± 0.22 vs. 4.62 ± 0.07 mg/g; P < 0.05) hearts. Female hearts of both strains exhibited a reduced basal contractility compared with strain-matched males [maximum first derivative of pressure (dP/dtmax): NHR, 4,036 ± 171 vs. 4,258 ± 152 mmHg/s; and HHR, 3,974 ± 160 vs. 4,540 ± 259 mmHg/s; P < 0.05]. HHR hearts were more susceptible to I/R (I = 25 min, and R = 30 min) injury than NHR hearts (decreased functional recovery, and increased lactate dehydrogenase efflux). Female NHR hearts exhibited a significantly greater recovery (dP/dtmax) post-I/R relative to male NHR (95.0 ± 12.2% vs. 60.5 ± 9.4%), a resistance to postischemic dysfunction not evident in female HHR (29.0 ± 5.6% vs. 25.9 ± 6.3%). Ventricular fibrillation was suppressed, and expression levels of Akt and ERK1/2 were selectively elevated in female NHR hearts. Thus the occurrence of load-independent primary cardiac hypertrophy undermines the intrinsic resistance of female hearts to I/R insult, with the observed abrogation of endogenous cardioprotective signaling pathways consistent with a potential mechanistic role in this loss of protection.r />

Collapse of an avifauna : climate change appears to exacerbate habitat loss and degradation

Aim. We characterized changes in reporting rates and abundances of bird species over a period of severe rainfall deficiency and increasing average temperatures. We also measured flowering in eucalypts, which support large numbers of nectarivores characteristic of the region.r />r />Location.  A 30,000-km2 region of northern Victoria, Australia, consisting of limited amounts of remnant native woodlands embedded in largely agricultural landscapes.r />r />Methods. There were three sets of monitoring studies, pitched at regional  (survey programmes in 1995–97, 2004–05 and 2006–08), landscape (2002–03 and 2006–07) and site (1997–2008 continuously) scales. Bird survey techniques used a standard 2-ha, 20-min count method. We used Bayesian analyses of reporting rates to document statistically changes in the avifauna through time at each spatial scale.r />r />Results. Bird populations in the largest remnants of native vegetation (up to 40,000 ha), some of which have been declared as national parks in the past decade, experienced similar declines to those in heavily cleared andscapes. All categories of birds (guilds based on foraging substrate, diet, nest site; relative mobility; geographical distributions) were affected similarly. We detected virtually no bird breeding in the latest survey periods. Eucalypt flowering has declined significantly over the past 12 years of drought.r />r />Main conclusions. Declines in the largest woodland remnants commensurate with those in cleared landscapes suggest that reserve systems may not be relied upon to sustain species under climate change. We attribute population declines to low breeding success due to reduced food. Resilience of bird populations in this woodland system might be increased by active management to enhance habitat quality in existing vegetation and restoration of woodland in the more fertile parts of landscapes.

Advice for international students on assessment practices in Australia

This guide provides a brief overview of the practices of assessment of learning in Australian universities. The information, suggestions and advice that follow will be especially useful if you are an international student who has little or no experience of the Australian university system. It will also be useful if you have had experience of assessment methods that are very different from Australian university practices, either at high school or university in another country.r />

Assessing group work

When effective group management processes are employed, clear assessment guidelines developed and communicated and valid and fair grading processes employed, the likelihood of positive learning outcomes and student satisfaction with group activities is significantly increased. Alternatively, if students cannot see the objective of group work, are unsure of what is expected of them, or believe the assessment methods are invalid or simply unfair, the educational benefits are reduced and tensions can emerge. The conditions under which group work is conducted are crucial to its success:r />r />Group work, under proper conditions, encourages peer learning and peer support and many studies validate the efficacy of peer learning. Under less than ideal conditions, group work can become the vehicle for acrimony, conflict and freeloading. It may also impose a host of unexpected stresses on, for example, students with overcrowded schedules living long distances from the University.r />(University of Wollongong assessment policy, 2002).r />r />The educational benefits of students working cooperatively in groups are well recognised. Among other things,r />• studying collaboratively has been shown to directly enhance learning;r />• employers value the teamwork and other generic skills that group work may help develop; andr />• group activities may help academic staff to effectively utilise their own time.r />r />The design of assessment is central to capturing the benefits of group work and avoiding its pitfalls. Assessment defines the character and quality of group work. In fact, the way in which students approach group work is largely determined by the way in which they are to be assessed.r />r />To maximise student learning in group activities, this section offers advice on how academic staff can:r />• establish explicit guidelines for group work to ensure that learning objectives are met and to ensure that they are transparent and equitable; andr />• manage the planning, development and implementation of processes and procedures for learning through group work and group assessment.r />

Advice on assessing large classes

After a decade of rapid expansion in Australian higher education, student numbers have grown considerably in many courses and subjects, especially at the undergraduate level.r />Larger class sizes pose significant teaching challenges, not least in the assessment of student learning. Perhaps most troubling, large classes may limit the amount of feedback provided to students.r />In response to the pressures and challenges of assessing larger groups of students, academic staff are responding through:r />• greater attention to the communication of clear assessment criteria to students;r />• the development and use of marking guides to be used by teaching and assessing teams;r />• the increasing use of various forms of exemplars to guide student efforts — as well as to guide marking and grading — including the modelling of discipline-based thinking, writing and performance; andr />• the continuous refinement and dissemination of assessment policy and practice in relation to large student groups.r />The issue of workload is central in any decisions about assessment of large classes for it is a serious one for students and staff alike. Staff teaching large student groups invariably undertake an informal, qualitative weighing-up of the efficiency of assessment tasks vis-&agrave;-vis their educational effectiveness.r />There is little doubt that establishing an effective assessment program — developing criteria, guides, exemplars and models; discussing and refining them and communicating them to students and other staff — will have an initial negative impact on workload for staff with coordinating responsibilities.r />However, this preparatory work is likely to lead to three gains. The first is a reduction in the time required for marking due to a higher quality of student submission. The second is a resolution of some of the potential issues likely when many staff are involved in marking and grading, through a streamlining of marking and grading practices. Finally, the availability of clear, transparent criteria and examples of work will contribute positively to the overall quality of teaching and learning.r />

Minimising plagiarism

Universities throughout the world have become concerned with the question of how to minimise and respond appropriately to student plagiarism and other forms of cheating. Australian universities are highly active in educating students about plagiarism and in detecting breaches of their academic expectations. The advice and resources provided here are designed to assist these efforts.r />