Fouling of waste heat recovery : numerical and experimental results

Numerical results are presented to investigate the performance of a partly-filled porous heat exchanger for waste heat recovery units. A parametric study was conducted to investigate the effects of inlet velocity and porous block height on the pressure drop of the heat exchanger. The focus of this work is on modelling the interface of a porous and non-porous region. As such, numerical simulation of the problem is conducted along with hot-wire measurements to better understand the physics of the problem. Results from the two sources are then compared to existing theoretical predictions available in the literature which are unable to predict the existence of two separation regions before and after the porous block. More interestingly, a non-uniform interface velocity was observed along the streamwise direction based on both numerical and experimental data.

Statistical methods for electromyography data and associated problems

This thesis proposes three novel models which extend the statistical methodology for motor unit number estimation, a clinical neurology technique. Motor unit number estimation is important in the treatment of degenerative muscular diseases and, potentially, spinal injury. Additionally, a recent and untested statistic to enable statistical model choice is found to be a practical alternative for larger datasets. The existing methods for dose finding in dual-agent clinical trials are found to be suitable only for designs of modest dimensions. The model choice case-study is the first of its kind containing interesting results using so-called unit information prior distributions.

Adaptive finite element analysis of elliptic problems based on bubble-type local mesh generation

A new mesh adaptivity algorithm that combines a posteriori error estimation with bubble-type local mesh generation (BLMG) strategy for elliptic differential equations is proposed. The size function used in the BLMG is defined on each vertex during the adaptive process based on the obtained error estimator. In order to avoid the excessive coarsening and refining in each iterative step, two factor thresholds are introduced in the size function. The advantages of the BLMG-based adaptive finite element method, compared with other known methods, are given as follows: the refining and coarsening are obtained fluently in the same framework; the local a posteriori error estimation is easy to implement through the adjacency list of the BLMG method; at all levels of refinement, the updated triangles remain very well shaped, even if the mesh size at any particular refinement level varies by several orders of magnitude. Several numerical examples with singularities for the elliptic problems, where the explicit error estimators are used, verify the efficiency of the algorithm. The analysis for the parameters introduced in the size function shows that the algorithm has good flexibility.

Translocation of bats as a conservation strategy : previous attempts and potential problems

Translocation is an increasingly popular conservation tool from which a wide range of taxa have benefited. However, to our knowledge, bats have not been translocated successfully. Bats differ behaviourally, morphologically and physiologically from the taxa for which translocation the- ory has been developed, so existing guidelines may not be directly transferable. We review previous translocations of bats and discuss characteristics of bats that may require special consideration dur- ing translocation. Their vagility and homing ability, coloniality, roost requirements, potential ability to transmit diseases, susceptibility to anthropomorphic impacts, and cryptic nature have implications for establishing populations, effects of these populations on the release site, and ability to monitor translocation success following release. We hope that our discussion of potential problems will be able to supplement the existing, more generic guidelines to provide a starting point for the planning of bat translocations.

Fruit-feeding behaviour and use of olfactory cues by the fruit bat Rousettus leschenaulti: an experimental study

This paper describes the feeding behaviour ofRousettus leschenaulti Desmarest, 1820 on lychees, the preferred cultivated food of this bat in captive conditions. We found that feeding comprised 25–30% of the total activity of these animals in a flight cage and that feeding durations were not significantly different between two sexes. To evaluate the role of odor and vision in foraging behaviour, we provided animals with artificial lychees, real lychees and artificial lychees soaked in the juice of real lychees and we recorded the number of feeding approaches to the different “fruit” types. The results indicated that bats approached real fruit significantly more than artificial fruit, and that the number of approaches to the soaked artificial fruit was also significantly higher than to the unsoaked artificial fruit. There were no significant differences between sexes in approach rates to any “fruit” type. We discuss the role of different sensory cues in the foraging behaviour of these bats and emphasize that the olfactory cue is important in detecting food resources and discriminating between different kinds of food items.

Stefan problems for melting nanoscaled particles

Under certain conditions, the mathematical models governing the melting of nano-sized particles predict unphysical results, which suggests these models are incomplete. This thesis studies the addition of different physical effects to these models, using analytic and numerical techniques to obtain realistic and meaningful results. In particular, the mathematical "blow-up" of solutions to ill-posed Stefan problems is examined, and the regularisation of this blow-up via kinetic undercooling. Other effects such as surface tension, density change and size-dependent latent heat of fusion are also analysed.

Development of fourth-grade students’ understanding of experimental and theoretical probability

Students explored variation and expectation in a probability activity at the end of the first year of a 3-year longitudinal study across grades 4-6. The activity involved experiments in tossing coins both manually and with simulation using the graphing software, TinkerPlots. Initial responses indicated that the students were aware of uncertainty, although an understanding of chance concepts appeared limited. Predicting outcomes of 10 tosses reflected an intuitive notion of equiprobability, with little awareness of variation. Understanding the relationship between experimental and theoretical probability did not emerge until multiple outcomes and representations were generated with the software.

The influence of injury cause, contact-sport participation, and personal knowledge on expectation of outcome from mild traumatic brain injury

Objective: This study investigated the influence of injury cause, contact-sport participation, and prior knowledge of mild traumatic brain injury (mTBI) on injury beliefs and chronic symptom expectations of mTBI. Method: A total of 185 non-contact-sport players (non-CSPs) and 59 contact-sport players (CSPs) with no history of mTBI were randomly allocated to one of two conditions in which they read either a vignette depicting a sport-related mTBI (mTBIsport) or a motor-vehicle-accident-related mTBI (mTBIMVA). The vignettes were otherwise standardized to convey the same injury parameters (e.g., duration of loss of consciousness). After reading a vignette, participants reported their injury beliefs (i.e., perceptions of injury undesirability, chronicity, and consequences) and their expectations of chronic postconcussion syndrome (PCS) and posttraumatic stress disorder (PTSD) symptoms. Results: Non-CSPs held significantly more negative beliefs and expected greater PTSD symptomatology and greater PCS affective symptomatology from an mTBIMVA vignette thann mTBIsport vignette, but this difference was not found for CSPs. Unlike CSPs, non-CSPs who personally knew someone who had sustained an mTBI expected significantly less PCS symptomatology than those who did not. Despite these different results for non-CSPs and CSPs, overall, contact-sport participation did not significantly affect injury beliefs and symptom expectations from an mTBIsport. Conclusions: Expectations of persistent problems after an mTBI are influenced by factors such as injury cause even when injury parameters are held constant. Personal knowledge of mTBI, but not contact sport participation, may account for some variability in mTBI beliefs and expectations. These factors require consideration when assessing mTBI outcome.

Experimental Study of crack propagation in carbon steel using acoustic emission

Acoustic emission technique has become a significant and powerful structural health monitoring tool for structures. Researches to date have been done on crack location, fatigue crack propagation in materials and severity assessment of failure using acoustic emission technique. Determining severity of failure in steel structures using acoustic emission technique is still a challenge to accurately determine the relationship between the severity of crack propagation and acoustic emission activities. In this study three point bending test on low carbon steel samples along with acoustic emission technique have been used to determine crack propagation and severity. A notch is introduced at the tension face of the loading point to the samples to initiate the crack. The results show that the percentage of load drop of the steel specimen has a reciprocal relationship with the crack opening i.e. crack opening zones are influenced by the loading rate. In post yielding region, common acoustic emission signal parameters such as, signal strength, energy and amplitudes are found to be higher than those at pre-yielding and at yielding.

Do we need a law to help people try experimental drugs?

People with life-threatening or incurable diseases may be willing to try experimental drugs and unproven treatments, but they face the risk of exploitation. Is the law the best avenue to ensure that they are protected while medical innovation is encouraged? Protection of vulnerable people is a thread running through many laws, in Australia and elsewhere. In medical law, for instance, children and people with impaired decision-making capacity warrant special attention. But what of the ordinary person diagnosed with a life-threatening disease? Such people are vulnerable to harm and potential exploitation when they seek access to innovative, experimental or unproven treatments that depart from the existing range of accepted medicine.

A generalised deficit can account for problems in facial emotion recognition in schizophrenia

Neuroimaging research has shown localised brain activation to different facial expressions. This, along with the finding that schizophrenia patients perform poorly in their recognition of negative emotions, has raised the suggestion that patients display an emotion specific impairment. We propose that this asymmetry in performance reflects task difficulty gradations, rather than aberrant processing in neural pathways subserving recognition of specific emotions. A neural network model is presented, which classifies facial expressions on the basis of measurements derived from human faces. After training, the network showed an accuracy pattern closely resembling that of healthy subjects. Lesioning of the network led to an overall decrease in the network’s discriminant capacity, with the greatest accuracy decrease to fear, disgust and anger stimuli. This implies that the differential pattern of impairment in schizophrenia patients can be explained without having to postulate impairment of specific processing modules for negative emotion recognition.

The effectiveness of psychosocial interventions for cognitive dysfunction in cancer patients who have received chemotherapy : a systematic review

Background: Chemotherapy-related cognitive dysfunction (CRCD) refers to problems with memory,attention span, or concentration, experienced by patients with cancer who have had chemotherapy. CRCD can have a significant negative effect on a patient’s quality of life. The exact cause of CRCD is unknown but is presumed to be multifactorial. Objective: To conduct a systematic review of the effectiveness of psychosocial interventions designed to treat CRCD. Methods: Participants of interest to the review were over 18 years of age, diagnosed with cancer, and receiving chemotherapy or had received chemotherapy in the past. Interventions of interest were methods to improve cognitive function. Included study designs were randomized controlled trials, quasi-experimental trials, and quantitative observational studies. The primary outcome of interest was level of cognitive function. A three-step search strategy was utilized to identify studies published from 1985 to 2011 from a wide range of databases. Joanna Briggs Institute systematic review methods were used but findings were analyzed using the Cochrane Collaboration Review Manager 5.1 program.Weightedmean differences with 95% confidence intervals were calculated from the continuous data. Results: Searching identified 3,109 potentially relevant articles and 120 full-text articles were retrieved. Two further papers were sourced from reference lists of retrieved articles. From 122 papers, six were suitable for critical appraisal and six were included in the analysis. Meta-analysis was conducted on two cognitive behavioral therapy (CBT) trials for the outcome of inability to concentrate. Significant effect was seen for one CBT intervention at 20 weeks (p = .004). Significant effect from CBT on quality of life was seen at 6-month follow-up (p < .05). Conclusions: Despite some evidence of an effect, there is insufficient evidence at this stage to strongly recommend any of the interventions to assist in decreasing the effects of CRCD, except in terms of improving quality of life.

Developing and evaluating interventions that are applicable and relevant to inpatients and those who care for them; a multiphase, pragmatic action research approach

Background Randomised controlled trials may be of limited use to evaluate the multidisciplinary and multimodal interventions required to effectively treat complex patients in routine clinical practice; pragmatic action research approaches may provide a suitable alternative. Methods A multiphase, pragmatic, action research based approach was developed to identify and overcome barriers to nutritional care in patients admitted to a metropolitan hospital hip-fracture unit. Results Four sequential action research cycles built upon baseline data including 614 acute hip-fracture inpatients and 30 purposefully sampled clinicians. Reports from Phase I identified barriers to nutrition screening and assessment. Phase II reported post-fracture protein-energy intakes and intake barriers. Phase III built on earlier results; an explanatory mixed-methods study expanded and explored additional barriers and facilitators to nutritional care. Subsequent changes to routine clinical practice were developed and implemented by the treating team between Phase III and IV. These were implemented as a new multidisciplinary, multimodal nutritional model of care. A quasi-experimental controlled, ‘before-and-after’ study was then used to compare the new model of care with an individualised nutritional care model. Engagement of the multidisciplinary team in a multiphase, pragmatic action research intervention doubled energy and protein intakes, tripled return home discharge rates, and effected a 75% reduction in nutritional deterioration during admission in a reflective cohort of hip-fracture inpatients. Conclusions This approach allowed research to be conducted as part of routine clinical practice, captured a more representative patient cohort than previously reported studies, and facilitated exploration of barriers and engagement of the multidisciplinary healthcare workers to identify and implement practical solutions. This study demonstrates substantially different findings to those previously reported, and is the first to demonstrate that multidisciplinary, multimodal nutrition care reduces intake barriers, delivers a higher proportional increase in protein and energy intake compared with baseline than other published intervention studies, and improves patient outcomes when compared with individualised nutrition care. The findings are considered highly relevant to clinical practice and have high translation validity. The authors strongly encourage the development of similar study designs to investigate complex health problems in elderly, multi-morbid patient populations as a way to evaluate and change clinical practice.

Behavioral consistency, the homology assumption, and the problems of induction

The ultimate goal of profiling is to identify the major behavioral and personality characteristics to narrow the suspect pool. Inferences about offender characteristics can be accomplished deductively, based on the analysis of discrete offender behaviors established within a particular case. They can also be accomplished inductively, involving prediction based on abstract offender averages from group data (these methods and the logic on which they are based is detailed extensively in Chapters 2 and 4). As discussed, these two approaches are by no means equal.