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Beware the black box: investigating the sensitivity of FEA simulations to modelling factors in comparative biomechanics
No full textFinite element analysis (FEA) is a computational technique of growing popularity in the field of comparative biomechanics, and is an easily accessible platform for form-function analyses of biological structures. However, its rapid evolution in recent years from a novel approach to common practice demands some scrutiny in regards to the validity of results and the appropriateness of assumptions inherent in setting up simulations. Both validation and sensitivity analyses remain unexplored in many comparative analyses, and assumptions considered to be 'reasonable' are often assumed to have little influence on the results and their interpretation. Here we report an extensive sensitivity analysis where high resolution finite element (FE) models of mandibles from seven species of crocodile were analysed under loads typical for comparative analysis: biting, shaking, and twisting. Simulations explored the effect on both the absolute response and the interspecies pattern of results to variations in commonly used input parameters. Our sensitivity analysis focuses on assumptions relating to the selection of material properties (heterogeneous or homogeneous), scaling (standardising volume, surface area, or length), tooth position (front, mid, or back tooth engagement), and linear load case (type of loading for each feeding type). Our findings show that in a comparative context, FE models are far less sensitive to the selection of material property values and scaling to either volume or surface area than they are to those assumptions relating to the functional aspects of the simulation, such as tooth position and linear load case. Results show a complex interaction between simulation assumptions, depending on the combination of assumptions and the overall shape of each specimen. Keeping assumptions consistent between models in an analysis does not ensure that results can be generalised beyond the specific set of assumptions used. Logically, different comparative datasets would also be sensitive to identical simulation assumptions; hence, modelling assumptions should undergo rigorous selection. The accuracy of input data is paramount, and simulations should focus on taking biological context into account. Ideally, validation of simulations should be addressed; however, where validation is impossible or unfeasible, sensitivity analyses should be performed to identify which assumptions have the greatest influence upon the results
Using relationship-based procurement for the provision of infrastructure
No full textThe last two decades has seen the evolution of Relational Contracting methods, such as Public Private Partnerships (PPPs), as alternative procurement approaches to traditional methods of delivering public infrastructure. Competing demands for public sector investment for new infrastructure has prompted Australian governments to increasingly turn to the private sector to form partnerships in the finance, design, construction, ownership and operation of infrastructure assets. This has become a major challenge but the emergence of PPPs provides an alternate means for developing infrastructure using private sector expertise. There is considerable growth potential for PPPs given that the New South Wales Government has developed policies to expand the application of PPPs to include social infrastructure, such as healthcare and schools. A key argument for all levels of Government (Federal, State and Local) to procure projects using PPPs is that the process would deliver better overall value for all the stakeholders. The aim of this paper is to investigate current approaches to successful risk management of infrastructure using the Top Ryde mixed-use PPP project as a case study. Top Ryde was one of the first and largest PPPs in NSW where the main public sector entity was Local Government (i.e. Council) as opposed to State Government). This involves an analysis of project documentation and a semi-structured interview process with key project stakeholders from both the public and private sectors. The results of this research centres around an effective tri-partite contract agreement, innovative relationship management and a very successful risk management approach with a particular focus on legal, financial and community factors
Medical oncology patients: are they offered help and does it provide relief?
No full textContext: Identifying modifiable gaps in the symptom management pathway, as perceived by patients, is the first step to relieving patient suffering. Objectives: The objective is to describe the proportion of patients experiencing treatable cancer-related symptoms who reported: 1) A health care provider at the treatment center offered assistance for their symptom. ; 2) They accepted the assistance offered. ; 3) The assistance relieved suffering. Variation in symptom management among treatment centers also was examined. Methods: A survey was done with 528 medical oncology outpatients recruited from six treatment centers. Eight items explored management of prevalent, burdensome, and treatable cancer-related symptoms: pain, fatigue, other physical side effects, and emotional distress. Participants were asked about symptom management provided at the clinic from where they were recruited. Questions referred to the last occasion the patient experienced the symptom. Results Fewer patients were offered help to relieve fatigue (44%) and emotional distress (57%), than pain (90%) and other physical side effects (84%). In most cases, help was not offered as clinic staff were not aware of the patient's symptom. Although the vast majority of patients accepted the help that was offered, more patients accepted help for physical symptoms (pain, 97%; fatigue, 95%; and other side effects, 98%) than emotional symptoms (87%). When care was provided, most patients experienced at least a little relief from pain (99%), fatigue (94%), and emotional distress (96%). Symptom management did not vary significantly by treatment center (P = 0.073). Conclusion: Quality improvement initiatives must focus primarily on improving providers' awareness of their patients' symptoms and ensuring that patients are subsequently offered help
Aboriginal and Torres Strait Islander health: accuracy of patient self-report of screening for diabetes, high cholesterol and cervical cancer
No full textTo determine the accuracy and clinical utility of patient self-reported screening history. Aboriginal and Torres Strait Islander patients (=18 years; n=587) were interviewed on their screening history according to recommended time intervals; these were matched to pathology data. The proportion of patients meeting screening guidelines were 32%(95%CI 26%-39%) for diabetes, 43%(95%CI 38%-47%) for cholesterol and 4.1%(95%CI 2.2%-7.3%) for cervical cancer. When patients reported having had the test, their accuracy (PPV) was low: 38%(95%CI 30%-46%) for diabetes, 47%(95%CI 42%-52%) for cholesterol, 6.5%(95%CI 3.0%-12%) for cervical cancer. However, for the minority of patients who had been screened, positive recall (sensitivity) was high: 94%(95%CI 85%-98%) for diabetes, 83%(95%CI 77%-88%) for cholesterol, 90%(95%CI 55%-98%) for cervical cancer. The accuracy of patient recall was good for those who reported not having been screened (NPV): 90%(95%CI 77%-97%) for diabetes, 70%(95%CI 61%-78%) for cholesterol, 99%(95%CI 95%-100%) for cervical cancer.The results indicate that reliance on self-report for patients' screening history is inappropriate due to missed opportunities for health gain. However, patients who report not being tested are sufficiently accurate to ensure that ordering the test in this group will involve only a small percentage of unnecessary assays. GPs often rely on self-report as a fast and inexpensive way to determine whether a patient requires screening. New strategies are needed to identify patients at risk
Conformation of poly(ethylene oxide) dissolved in the solvate ionic liquid [Li(G4)]TFSI
No full textThe conformation of 38 kDa PEO in a solvate ionic liquid (SIL), lithium tetraglyme bis(trifluoromethanesulfonyl)amide ([Li(G4)]TFSI) from dilute to concentrated solution regimes has been determined by small angle neutron scattering and rheology. SANS analysis reveals that [Li(G4)]TFSI is better than a theta solvent (theta-good) for PEO. The variation of the radius of gyration (Rg) and viscosity as a function of polymer concentration allow the overlap concentrations, c* and c**, to be identified at 13 mg mL⁻¹ and 50 mg mL⁻¹, respectively, which are similar to values reported previously for conventional ionic liquids. Unlike water and conventional ionic liquids, [Li(G4)]TFSI cannot form hydrogen bonds with PEO. Thermal
gravimetric analysis indicates that the solvation of PEO by [Li(G4)]TFSI is a consequence of PEO forming coordinate bonds with the lithium by displacing the anion, but without displacing the glyme molecule
Dataset for "Clinical and pharmacological investigation of myotoxicity in Sri Lankan Russell's viper (Daboia russelii) envenoming"
No full textAll clinical and experimental data for the journal article "Clinical and pharmacological investigation of myotoxicity in Sri Lankan Russell's viper (Daboia russelii) envenoming
Factors related to previous tuberculosis treatment of patients with multidrug-resistant tuberculosis in Bangladesh
No full textObjective: Previous tuberculosis (TB) treatment status is an established risk factor for multidrug-resistant TB (MDR-TB). This study explores which factors related to previous TB treatment may lead to the development of multidrug resistant in Bangladesh. Design: We previously conducted a large case–control study to identify risk factors for developing MDR-TB in Bangladesh. Patients who had a history of previous TB treatment, either MDR-TB or non-MDR-TB, were interviewed about their previous treatment episode. This study restricts analysis to the strata of patients who have been previously treated for TB. Information was collected through face-to-face interviews and record reviews. Unadjusted and multivariable logistic regression was used for data analysis. Setting: Central-level, district-level and subdistrict-level hospitals in rural and urban Bangladesh. Results: The strata of previously treated patients include a total of 293 patients (245 current MDR-TB; 48 non-MDR-TB). Overall, 54% of patients received previous TB treatment more than once, and all of these patients were multidrug resistant. Patients with MDR-TB were more likely to have experienced the following factors: incomplete treatment (OR 4.3; 95% CI 1.7 to 10.6), adverse reactions due to TB treatment (OR 8.2; 95% CI 3.2 to 20.7), hospitalisation for symptoms associated with TB (OR 16.9; CI 1.8 to 156.2), DOTS (directly observed treatment, short-course) centre as treatment unit (OR 6.4; CI 1.8 to 22.8), supervised treatment (OR 3.8; CI 1.6 to 9.5); time-to-treatment centre (OR 0.984; CI 0.974 to 0.993). Conclusions: Incomplete treatment, hospitalisation for TB treatment and adverse reaction are the factors related to previous TB treatment of patients with MDR-TB. Although the presence of supervised treatment (DOT), less time-to-treatment centres and being treated in DOTS centres were relatively higher among the patients with MDR-TB compared with patients without MDR-TB, these findings include information of their most recent TB treatment episode only. Most (64.5%) of the patients with MDR-TB had received TB treatment more than once
WaveWatch, an ambient information system displaying real-time web traffic data
No full textThe WaveWatch display was developed through an iterative design process, with a number of prototypes being developed before the deployment and evaluation of the final design. Overall it was found that creating an Ambient Information System that utilises 3D graphics and an ocean wave metaphor was technically feasibility. However, building the display was a complicated and lengthy process taking around 200 man-hours. This process was complicated by a number of design challenges including the creation of an aesthetically pleasing scene, the time for each scene to render, the creation of a real-time dynamic looping ocean animation and the limitations of current video playback technology. Despite these technical difficulties it was possible to combine existing technologies to create the novel Ambient Information System known as WaveWatch. An instrumental case study was performed, where the WaveWatch display was deployed in a real life office environment for a period of two weeks. After this two-week evaluation period, participants who worked in the area were given the chance to complete a questionnaire related to the utility and perceived ease of use of the display. The key finding from this instrumental case study was that the majority of respondents found the novel wave metaphor for peripheral information visualisation to be a useful tool for generating interest in the underlying data source, where the metaphor itself was perceived to be both intuitive and easy to understand
Dual time-frequency domain system identification
No full textIn this paper we obtain the maximum likelihood estimate of the parameters of discrete-time linear models by using a dual time–frequency domain approach. We propose a formulation that considers a (reduced-rank) linear transformation of the available data. Such a transformation may correspond to different options: selection of time-domain data, transformation to the frequency domain, or selection of frequency-domain data obtained from time-domain samples. We use the proposed approach to identify multivariate systems represented in state–space form by using the Expectation–Maximisation algorithm. We illustrate the benefits of the approach via numerical examples
The impact of group singing on health-related quality of life in Parkinson’s disease: a qualitative study
No full textScope: Idiopathic Parkinson’s disease (PD) is a chronic, progressively disabling neurological disorder, comprising both motor symptoms (MS) and non-motor symptoms (NMS). People with PD have reduced health-related quality of life (HRQoL; Karlsen, Tandberg, Årsland, & Larsen, 2000; Simpson, Lekwuwa, & Crawford, 2014). To date there is no cure for PD. The primary goal of treatment is to restore or maintain HRQoL through assessment and intervention, while simultaneously managing MS (Fung, 2015). PD predominately affects older adults. Deloitte Access Economics (2015) confirms that in Australia PD is the most common major movement disorder and the second highest prevalence neurodegenerative condition (after Alzheimer’s disease). The estimated prevalence is approximately 70,000 (one in every 340 people) with an economic cost to the country of over $9.9 billion. In 2014, there were 11,900 new cases of PD diagnosed; this rate is expected to grow by 4% per annum over the next 20 years, compared to the general population growth rate of 1%, due to the aging population. Purpose: Group singing is a non-pharmacological, low cost, community-based activity that has been found to improve HRQoL (Clift & Hancox, 2010; Judd & Pooley, 2013) across a variety of populations: mental health (Tavormina, Tavormina, & Nemoianni, 2014), cancer (Gale, Enright, Reagon, Lewis & Deursen, 2012) and neurological conditions including Alzheimer’s disease (Simons-Stern, Budson & Ally, 2010), dementia (Osman, Tischler & Schneider, 2014) and stroke (Tamplin, Baker, Jones, Way, & Lee, 2013; Tomaino, 2012). The aim of this study was to explore the effects of group singing on HRQoL for people diagnosed with PD.
Methodology: Eleven participants (mean age 70.6 years) with a formal diagnosis of PD were recruited from an existing community singing group specifically created for people with PD, their carers and family members. Participants presented with mild to moderate severity of MS and disability (Hoehn and Yahr stage (frequency): level I (6), level II (3) and level III (2)) and moderate to very severe NMS burden (NMSB; (frequency): moderate (4), severe (5) and very severe (2)) and low to significantly impacted HRQoL (Parkinson Disease Questionnaire-39 scores ranged from 6.93 to 43.59). Interpretive Phenomenological Analysis (IPA; Smith, 1996), a qualitative methodology well established in the field of health psychology (Brocki & Wearden, 2006), informed the data collection and analysis. To ensure research rigour, the recommendations of the Consolidated Criteria for Reporting Qualitative Studies (COREQ; Tong, Sainsbury & Craig, 2007) were incorporated into the research design. Participants’ perceptions of the effect of group singing on their HRQoL were captured in a semi-structured interview designed for this research. Results: All participants reported improved wellbeing since attending the choir and a desire to recommend the singing group to others with PD. The results of the IPA analysis revealed six themes that characterised the effects of group singing: physical, mood, cognitive functioning, social connectedness, ‘flow-on’ effects, and sense-of-self. All participants reported positive effects across at least four of these themes. Three participants reported a negative effect in at least one theme (physical, mood or sense-of-self). The most common sub-themes reported by participants were related to social connectedness, with all participants reporting camaraderie and new friendships as important aspects of attending the choir. Other sub-themes, identified by the majority of participants, included improved voice quality, raised energy levels, PD-specific choir, enhanced mood, increased self-confidence and greater control over day-to-day activities. Three factors were identified as important in the success of the choir: the Choir Maestro, PD-carer support group, and a PD-specific choir. General conclusions and implications: This study is unique for the following reasons. It is the only study to use a qualitative methodology to examine group singing and HRQoL in participants regularly attending a choir specifically established for people with PD, their carers and family members. It is the only study to report on the cognitive benefits of group singing in a PD specific choir, and the only study to report the duration of the effects across the domains of physical (body and voice), mood and cognitive functioning. Furthermore, this research has revealed both positive and negative effects of group singing, whereas previous studies have not reported on the latter in a PD specific choir. Participants reported multiple benefits from engagement in group singing that counteracted many of the negative effects of PD, suggesting that group singing has the ability to ‘give back’ some of what PD ‘takes away’