The diversity of network applications over the Internet has propelled researchers to rethink the strategies in the transport layer protocols. Current applications either use UDP without end-to-end congestion control mechanisms or, more commonly, use TCP. TCP continuously probes for bandwidth even at network steady state and thereby causes variation in the transmission rate and losses. This thesis proposes TCP Carson, a modification of the window-scaling approach of TCP Reno to suit long-lived flows using loss-events as indicators of congestion. We analyzed and evaluated TCP Carson using NS-2 over a wide range of test conditions. We show that TCP Carson reduces loss, improves throughput and reduces window-size variance. We believe that this adaptive approach will improve both network and application performance.

This portfolio presents a unique and significant body of research which together provides a substantial, original description and analysis of women’s engagement with weight management behaviours and services during pregnancy. This body of research examines this topic from multiple perspectives, concluding with a detailed interpretative study which sheds light on the deep-rooted determinants of women’s weight-related behaviours during pregnancy. All outputs are articles published in peer-reviewed scientific journals: Article one describes an evaluation of the acceptability of an individual, home-based perinatal weight management service, based on a qualitative examination of the experiences of obese women who used the service during pregnancy. The findings showed that women valued the support they received from the service, and highlighted home visits, personalised advice and regular weight monitoring as beneficial, while suggesting that more frequent appointments and practical support with target behaviours would enhance the service. Article two describes a qualitative study of the views and experiences of obese women who had declined or disengaged from the service evaluated in article one. The study identified the referral experience as key to women’s decisions to decline participation, highlighting the need for midwives and other health professionals to have detailed knowledge of the service and training on how to sensitively offer this additional support. Findings also demonstrated that some obese women lacked the confidence or capability to successfully change weight-related behaviours, even with support, leading them to disengage from the service. Article three compares and combines qualitative data obtained from two sets of midwives, each referring women to either a one to one, home-based weight management service, or a group, community-based weight management service, to explore how midwives approach the referral with obese and overweight women, and their views of women’s responses to being offered a referral. Findings highlighted the important role midwives play as gatekeepers to weight management services and raised questions regarding how midwives approach the referral process within the wider context of the maternal obesity issue. The findings also suggest that services might improve uptake through addressing pragmatic and motivational barriers, and through better communication with their referral agents. Article four describes analysis of qualitative data collected from women who declined a referral to a group, community-based weight management service during their pregnancy, specifically exploring their views on being referred to the service by their midwife. In contrast to the findings described in article two, women in this study reported finding the referral acceptable, and that they expected to receive information about such services from their midwife. The more positive response of these women could be attributed to a number of potential factors, including; an increase in women’s awareness of the risks of maternal obesity, an increase in midwives’ confidence and skill to raise the issue of weight in the time elapsed between the two studies, or a different approach to making the referral between the two services. Article five reports the findings of a qualitative study using Interpretive Phenomenological Analysis (IPA) which sought to explore in detail the lived experience of a first pregnancy and the process of making decisions about diet and physical activity during this time. The article aimed to further illuminate the multiple and significant barriers to adopting positive dietary and physical activity behaviours during pregnancy, and to challenge the commonly cited belief that ‘pregnancy is a good time for behaviour change’ by examining women’s experiences with specific reference to the model of ‘Teachable Moments’ (McBride, Emmons, & Lipkus 2003). While partially supporting the model, the results also indicated that women with healthy, uncomplicated conception and pregnancy experiences base their diet and physical activity choices primarily on automatic judgements, physical sensations and perceptions of what pregnant women are supposed to do, which in turn suggests limited opportunity for antenatal health professionals to intervene and subsequently influence behaviour. These accumulated findings suggest that there is much that can be done to increase obese women’s engagement with maternal weight management behaviours and services. Service providers and commissioners could draw on these findings to design services which better meet the needs of many obese women, such as receiving personalised support, at a time and location convenient for them, and providing regular weight monitoring. There are also implications for health professionals’ education and clinical practice, with findings indicating that midwives would benefit from further training and better information about the weight management services they are asked to refer to, in order to make referrals more evidence-based and increase their confidence to advocate for the service to women who might benefit. Finally, the work presented in this portfolio further informs our understanding of the psychosocial determinants of women’s weight-related behaviour during pregnancy. It suggests that researchers and practitioners should consider how to tackle the largely socially learned, sub-optimal behaviour patterns that are often established in early pregnancy and how to activate more reflective decision-making in relation to diet, physical activity and weight management. The portfolio also includes critical reflection on each of the outputs and the contribution of each unique study to the development of the author into an independent and expert researcher, and concludes with suggestions for future research.

Photocopy of typescript. / Digitized by Kansas Correctional Industries

Otosclerosis is a common form of adult-onset hearing loss. It is a complex disease that most likely involves multiple genetic and environmental factors. We know that a genetic component for otosclerosis exists because of the overwhelming ethnic bias and the fact that nearly half of patients report a family history. Many family linkage studies and candidate gene association studies have been performed; however, disease-causing mutations remain elusive. The disease is caused by abnormal bone remodeling in the otic capsule, which normally undergoes very little remodeling after development and ossification. This is in stark contrast to the rest of the skeleton, which undergoes bone turn over at a rate of nearly 10% per year. How the otic capsule remains in such a static state is under investigation, but initial studies suggest that bone remodeling inhibitors produced by the inner ear are responsible. In patients with otosclerosis it is uncertain what events trigger this abnormal bone remodeling. To determine its cause, many environmental and genetic factors have been entertained. However, even with decades of research on the disease, we still know little about its etiology. My thesis work has aimed to identify molecular and genetic contributors to the disease. To do this, I have performed a global gene expression analysis of otosclerotic tissue to determine what genes are differentially expressed in the disease compared to control tissue. This study has identified a number of differentially expressed genes and pathways potentially involved in the disease. To compliment this work, I also performed a genome-wide association study, in collaboration with a group from Belgium. Together we identified an unexpected gene, RELN, as being associated with otosclerosis in six different European populations. This marks the first successful genome-wide association study for a hearing impairment. I have also identified rare variants in several candidate genes in the TGF-â superfamily in otosclerosis patients. Further analysis of these variants has identified a few that appear to alter protein function, giving us a glimpse of what they may be doing to cause disease. While we still cannot account for most of the heritability for otosclerosis, we have come a long way in identifying new candidates, in which future analysis will hopefully lead to a better understanding of the disease. In the long term, I hope this work will help provide better treatment options for patients with this disease.

University of Technology, Sydney. Faculty of Humanities and Social Sciences. / This study aims to increase understanding of the critical themes and features of suicide grief through an analysis of data drawn from the lived experience of those bereaved by suicide. The theoretical context for this study is developments in new theories of grief. Specifically, the study focused on suicide grief in the context of meaning making and the influence of suicide on the griever’s relational world. The study analysed data through the lenses of three relationship areas, the griever’s relationship with self, the griever’s ongoing relationship with the deceased, and the griever’s relationships with significant others outside and within a grief group. Using an interpretive, hermeneutic methodology to analyse participant conversations, three central organising themes were identified. The proposed tripartite working model of suicide grief to emerge outlines a process of adaptation, from engaging with meaning making issues regarding the intentional nature of suicide, to reconstruction of the death story, to repositioning the suicide and pain of the deceased’s life. The metaphors of "trying on the shoes", "walking in the shoes" and "taking off the shoes" are used to indicate the grief process in relation to each identified theme. The thesis argues that suicide grief themes provide a meaning making framework that assists integrative grief processes. Not all those bereaved by suicide will engage with these themes, and progression through themes is not a linear process. The study findings provide insight into meaning making and relational difficulties that increase vulnerability to complications in grief, suicidality and maladaptive relationship with the deceased. Study findings also reveal that shifts from maladaptive to adaptive relationship with the deceased are possible even when no rational meanings can be made. It is suggested that these issues are so prevalent in suicide grief as to be a normal part of active meaning making efforts to integrate grief. The working model may assist in identifying ongoing education, practice and research issues. Significantly, the predominance of relating with the deceased through reconstruction of the death story, and the relationship between this and increased suicidal ideation to emerge in this study requires further research to determine how and when these activities shift from effective meaning making strategies to become active suicidality.

Objective: Since short-term weight loss is often achievable in overweight individuals but long-term weight maintenance is generally poor, this thesis examines the effect of the nature of support programmes and macronutrient composition on weight maintenance following weight loss. Research design and methods: A 2x2 multifactorial design was used to compare two support programmes and two diets differing in macronutrient composition on maintenance of weight loss over a 2-year period. Two hundred women who had recently lost at least 5% of initial body weight were randomised into one of two support programmes. One provided intensive expert, health professional support with regular circuit training classes. The other provided brief and frequent �weigh-ins� and support facilitated by a nurse. Participants were also randomised with regard to recommended diet composition. One eating plan was high in carbohydrate and dietary fibre, emphasising low glycemic index foods. The second eating plan was relatively high in monounsaturated fat and protein and had a low overall glycaemic load. At baseline, 1 and 2-years, weight, waist circumference and blood pressure were measured and body composition was estimated using bioelectrical impedance. Three-day weighed diet records were collected to estimate dietary intake. A fasting blood sample was used to measure glucose, insulin and lipids. Results: At 2-years weight was measured for 87% of participants. On average those randomised to the Expert Support Programme reduced weight by 2.5kg while those on the Nurse Support Programme reduced weight by 3.6kg (difference between support programmes, P=0.976). On the High Carbohydrate Diet average weight loss was 2.4kg compared with a loss of 3.8kg on the High Monounsaturated fat Diet (difference between diets, P=0.419). At follow-up, there were no signficant differences between the support programmes with regards to body composition, systolic and diastolic blood pressures, blood lipid levels, glucose, insulin, and predicted insulin sensitivity. From a health system perspective and relative to the Nurse Support Programme, the Expert Support Programme cost $NZ 928, 970 per QALY gained (or $9, 290 per person). At follow-up, there were no signficant differences between the dietary prescriptions with regard to body composition, systolic and diastolic blood pressures, triglycerides, HDL-cholesterol, glucose, insulin and predicted insulin sensitivity. However, total and LDL cholesterol were significantly lower on the High Carbohydrate Diet compared with the High Monounsaturated fat Diet (total cholesterol 0.2mmol/l, P=0.044, LDL cholesterol 0.2mmol/l, P=0.042). At follow-up those on the High Monounsaturated fat Diet reported significantly higher intakes of saturated fat (1.5%TE), total fat (5%TE), monounsaturated fat (2.4%), and a significantly lower intake of carbohydrate (-5%TE) than those on the High Carbohydrate Diet. Conclusion: A relatively inexpensive nurse led programme appears to be as effective as a more costly expert health professional led programme in achieving weight maintenance over a 2-year period. This inexpensive and successful weight maintenance programme offers a feasible option for implementation in primary health care in New Zealand. Similarly, both dietary approaches produced comparable beneficial effects in terms of weight loss maintenance. However the High Carbohydrate Diet was associated with lower levels of total and LDL cholesterol, possibly due to a lower intake of saturated fat.

<p>In this thesis an approach to CDO tranche valuation is described.</p><p>This approach allows to check market quotes for arbitrage opportunities,</p><p>to obtain expected portfolio losses from the market quotes</p><p>and to price CDO tranches with non-standard maturities and attachment/</p><p>detachment points. A significant advantage of this approach is</p><p>the possibility to avoid the necessity of construction of a correlation</p><p>structure between names in the reference basket. Standard approaches</p><p>to CDO valuation, based on copula functions are also considered.</p>

Thesis (Ph. D.)--Ohio State University, 2006. / Title from first page of PDF file. Includes bibliographical references (p. 126-136).

Virtualization technology has attracted considerable interest. It allows several virtual machines to run concurrently inside a physical host, which brings multiple advantages. One of the most useful features is called live migration, during which a virtual machine can be migrated over network with minimal disruption. So far, most existing migration algorithms are focused on transferring the runtime state over high-speed, low-delay network. They all require shared storage for file systems. However, this sharing sometimes becomes impossible because of performance loss. Thus, the whole system needs to be transferred during migration. In this thesis, we introduce a Virtual Machine Management System which contains a block-level solution. Combined with pre-copying the runtime state, we can migrate an entire virtual machine over low-bandwidth, high-delay network with minimum service downtime. We show that this is sufficient even for interactive workloads. We also provide snapshots and full backup for the virtual machine.

Thesis (M. Soc. Sc.)--University of Hong Kong, 2004.