Elaborazione di un modello di simulazione per una rete di trasporto multi-modale

Questo lavoro di tesi si prefigge l’obiettivo di simulare il trasporto di organi destinati a trapianto sul territorio nazionale italiano. Lo scopo della simulazione è mettere in luce le criticità e le eventuali soluzioni alternative in modo da raggiungere un duplice obiettivo: la certezza di portare a compimento il trasporto da un ospedale ad un altro entro i tempi clinici necessari affinché l’organo sia ancora utilizzabile e la riduzione dei costi del trasporto, che negli ultimi anni si sono rivelati elevati a causa del ricorso frequente a voli di Stato. Nella prima parte del lavoro viene delineato il problema e le necessità di ottimizzazione della rete, dopodiché si illustra il modello creato per simulare la situazione di as-is ed infine si espone il modello da utilizzare in futuro, dove si prevedono i tempi futuri di percorrenza. Per la modellazione della situazione attuale sono stati utilizzati due livelli di dettaglio diversi, uno che si basa sulla suddivisione dei trapianti in ingresso e uscita da una regione specifica e uno che approfondisce ulteriormente la rete modellando gli spostamenti di città in città. I modelli predittivi presentati sono due, uno che considera tempi predittivi deterministici e uno che considera tempi stocastici. Dopo ciascuna modellazione vengono esposti i risultati e le statistiche più significative; vengono infine messi in evidenza gli aspetti critici e gli sviluppi futuri della simulazione. Il software scelto per creare e simulare il trasporto degli organi sulla rete è Arena.

Continuity of care in older adults with multiple chronic conditions

Thesis (Ph.D.)--University of Washington, 2016-08

Nichtmedikamentöse Sekundärprävention der koronaren Herzkrankheit (KHK)

Hintergrund: Die koronare Herzkrankheit (KHK) ist eine häufige und potenziell tödliche Erkrankung mit einer Lebenszeitprävalenz von über 20%. Allein in Deutschland wird die Zahl der durch die ischämische Herzerkrankung und des akuten Myokardinfarkts jährlich verursachten Todesfälle auf etwa 140.000 geschätzt. Ein Zusammenhang eng mit dem Lebensstil verbundener Risikofaktoren mit Auftreten und Prognose der KHK ist nachgewiesen. Durch Maßnahmen der nichtmedikamentösen Sekundärprävention wird versucht, diese Risikofaktoren positiv zu verändern sowie die KHK im Gegensatz zu palliativen interventionellen Therapiestrategien kausal zu behandeln. Zur Wirksamkeit der nichtmedikamentösen sekundärpräventiven Maßnahmen liegt eine ganze Reihe von Einzelstudien und -untersuchungen vor, eine systematische Analyse, die die Evidenz aller hauptsächlich angewandten Sekundärpräventionsstrategien zusammenfasst, fehlt unseres Wissens nach bislang jedoch. Auch eine Auswertung vorhandener Studien zur Kosten-Effektivität der Maßnahmen ist hierbei zu integieren. Fragestellung: Ziel dieses HTA-Berichts (HTA=Health Technology Assessment) ist die Erstellung einer umfassenden Übersicht der aktuellen Literatur zu nichtmedikamentösen Sekundärpräventionsmaßnahmen in der Behandlung der KHK, um diese Maßnahmen und deren Komponenten bezüglich ihrer medizinischen Wirksamkeit sowie Wirtschaftlichkeit zu beurteilen. Weiterhin sollen die ethischen, sozialen und rechtlichen Aspekte der nichtmedikamentösen Sekundärprävention und die Übertragbarkeit der Ergebnisse auf den deutschen Versorgungsalltag untersucht werden. Methodik: Relevante Publikationen werden über eine strukturierte und hochsensitive Datenbankrecherche sowie mittels Handrecherche identifiziert. Die Literaturrecherche wird in vier Einzelsuchen zu medizinischen, gesundheitsökonomischen, ethischen und juristischen Themen am 18.09.2008 durchgeführt und erstreckt sich über die vergangenen fünf Jahre. Die methodische Qualität der Publikationen wird von jeweils zwei unabhängigen Gutachtern unter Beachtung von Kriterien der evidenzbasierten Medizin (EbM) systematisch geprüft. Ergebnisse: Von insgesamt 9.074 Treffern erfüllen 43 medizinische Publikationen die Selektionskriterien, mit einem Nachbeobachtungszeitraum zwischen zwölf und 120 Monaten. Insgesamt ist die Studienqualität zufriedenstellend, allerdings berichtet nur ca. die Hälfte der Studien differenziert die Gesamtmortalität, während die übrigen Studien andere Outcomemaße verwenden. Die Wirksamkeit einzelner Sekundärpräventionsmaßnahmen stellt sich als sehr heterogen dar. Insgesamt kann langfristig eine Reduktion der kardialen sowie der Gesamtmortalität und der Häufigkeit kardialer Ereignisse sowie eine Erhöhung der Lebensqualität beobachtet werden. Vor allem für trainingsbasierte und multimodale Interventionen ist eine effektive Reduktion der Mortalität zu beobachten, während psychosoziale Interventionen besonders in Bezug auf eine Erhöhung der Lebensqualität effektiv zu sein scheinen. Für die ökonomischen Auswertungen werden 26 Publikationen identifiziert, die von ihrer Themenstellung und Studienart dem hier betrachteten Kontext zugeordnet werden können. Insgesamt kann festgestellt werden, dass sich die Studienlage zur multimodalen Rehabilitation sowohl bezüglich ihrer Menge als auch Qualität der Analysen besser darstellt, als dies für Evaluationen von Einzelmaßnahmen beobachtet werden kann. Die internationale Literatur bestätigt den multimodalen Ansätzen dabei zwar ein gutes Verhältnis von Kosten und Effektivität, untersucht jedoch nahezu ausschließlich ambulante oder häuslichbasierte Maßnahmen. Die Auswertung der Studien, die einzelne sich mit präventiven Maßnahmen in Hinblick auf ihre Kosten-Effektivität beschäftigen, ergibt lediglich positive Tendenzen für Interventionen der Raucherentwöhnung und des körperlichen Trainings. Im Hinblick auf psychosoziale Maßnahmen sowie auch die Ernährungsumstellung können aufgrund der unzureichenden Studienlage jedoch keine Aussagen über die Kosten-Effektivität getroffen werden. Insgesamt werden im Rahmen der Betrachtung sozialer Aspekte der nichtmedikamentösen Sekundärprävention elf Publikationen einbezogen. Die relativ neuen Studien bestätigen, dass Patienten mit niedrigem sozioökonomischen Status insgesamt schlechtere Ausgangsbedingungen und demnach einen spezifischen Bedarf an rehabilitativer Unterstützung haben. Gleichzeitig sind sich die Forscher jedoch uneinig, ob gerade diese Patientengruppe relativ häufiger oder seltener an den Rehabilitationsmaßnahmen teilnimmt. Bezüglich der Barrieren, die Patienten von der Teilnahme an den präventiven Maßnahmen abhalten, werden psychologische Faktoren, physische Einschränkungen aber auch gesellschaftliche und systemisch-orientierte Einflüsse genannt. Diskussion: Nichtmedikamentöse Sekundärpräventionsmaßnahmen sind sicher und in der Lage eine Reduktion der Mortalität sowie der Häufigkeit kardialer Ereignisse zu erzielen sowie die Lebensqualität zu erhöhen. Da nur wenige der methodisch verlässlichen Studien Teilnehmer über einen längeren Zeitraum von mindestens 60 Monaten nachverfolgen, müssen Aussagen über die Nachhaltigkeit als limitiert angesehen werden. Verlässliche Angaben in Bezug auf relevante Patientensubgruppen lassen sich nur sehr eingeschränkt machen ebenso wie im Hinblick auf die vergleichende Beurteilung verschiedener Maßnahmen der Sekundärprävention, da diese von eingeschlossenen Studien nur unzureichend erforscht wurden. Zukünftige methodisch verlässliche Studien sind notwendig, um diese Fragestellungen zu untersuchen und zu beantworten. Bezogen auf die Kosten-Effektivität nichtmedikamentöser sekundärpräventiver Maßnahmen kann aus den internationalen Studien eine insgesamt positive Aussage zusammengefasst werden. Einschränkungen dieser resultieren jedoch zum einen aus den Besonderheiten des deutschen Systems der stationären Rehabilitationsangebote, zum anderen aus den qualitativ mangelhaften Evaluationen der Einzelmaßnahmen. Studien mit dem Ziel der Bewertung der Kosten-Effektivität stationärer Rehabilitationsangebote sind ebenso erforderlich wie auch qualitativ hochwertige Untersuchungen einzeln erbrachter Präventionsmaßnahmen. Aus sozialer Perspektive sollte insbesondere untersucht werden, welche Patientengruppe aus welchen Gründen von einer Teilnahme an Rehabilitations- bzw. präventiven Maßnahmen absieht und wie diesen Argumenten begegnet werden könnte. Schlussfolgerung: Nichtmedikamentöse sekundärpräventive Maßnahmen sind in der Lage eine Reduktion der Mortalität und der Häufigkeit kardialer Ereignisse zu erzielen sowie die Lebensqualität zu erhöhen. Eine Stärkung des Stellenwerts nichtmedikamentöser Maßnahmen der Sekundärprävention erscheint vor diesem Hintergrund notwendig. Auch kann für einige Interventionen ein angemessenes Verhältnis von Effektivität und Kosten angenommen werden. Es besteht allerdings nach wie vor erheblicher Forschungsbedarf bezüglich der Wirksamkeitsbeurteilung nichtmedikamentöser Maßnahmen der Sekundärprävention in wichtigen Patientensubgruppen und der Effizienz zahlreicher angebotener Programme. Darüber hinaus ist weitere Forschung notwendig, um die Nachhaltigkeit der Maßnahmen und Gründe für die Nichtinanspruchnahme detailliert zu untersuchen. Vor allem gilt es jedoch den Versorgungsalltag in Deutschland, wie er sich für Ärzte, Patienten und weitere Akteure des Gesundheitswesens darstellt, zu untersuchen und den heutigen Stellenwert nichtmedikamentöser Maßnahmen aufzuzeigen.

Transformer les pratiques professionnelles vis-à-vis des personnes prestataires de l’aide sociale : développement participatif et évaluation d’une formation continue en cabinet dentaire

L’objectif de la présente thèse est de générer des connaissances sur les contributions possibles d’une formation continue à l’évolution des perspectives et pratiques des professionnels de la santé buccodentaire. Prônant une approche centrée sur le patient, la formation vise à sensibiliser les professionnels à la pauvreté et à encourager des pratiques qui se veulent inclusives et qui tiennent compte du contexte social des patients. L’évaluation de la formation s’inscrit dans le contexte d’une recherche-action participative de développement d’outils éducatifs et de transfert des connaissances sur la pauvreté. Cette recherche-action aspire à contribuer à la lutte contre les iniquités sociales de santé et d’accès aux soins au Québec; elle reflète une préoccupation pour une plus grande justice sociale ainsi qu’une prise de position pour une santé publique critique fondée sur une « science des solutions » (Potvin, 2013). Quatre articles scientifiques, ancrés dans une philosophie constructiviste et dans les concepts et principes de l’apprentissage transformationnel (Mezirow, 1991), constituent le cœur de cette thèse. Le premier article présente une revue critique de la littérature portant sur l’enseignement de l’approche de soins centrés sur le patient. Prenant appui sur le concept d’une « épistémologie partagée », des principes éducatifs porteurs d’une transformation de perspective à l’égard de la relation professionnel-patient ont été identifiés et analysés. Le deuxième article de thèse s’inscrit dans le cadre du développement participatif d’outils de formation sur la pauvreté et illustre le processus de co-construction d’un scénario de court-métrage social réaliste portant sur la pauvreté et l’accès aux soins. L’article décrit et apporte une réflexion, notamment sur la dimension de co-formation entre les différents acteurs des milieux académique, professionnel et citoyen qui ont constitué le collectif À l’écoute les uns des autres. Nous y découvrons la force du croisement des savoirs pour générer des prises de conscience sur soi et sur ses préjugés. Les outils développés par le collectif ont été intégrés à une formation continue axée sur la réflexion critique et l’apprentissage transformationnel, et conçue pour être livrée en cabinet dentaire privé. Les deux derniers articles de thèse présentent les résultats d’une étude de cas instrumentale évaluative centrée sur cette formation continue et visant donc à répondre à l’objectif premier de cette thèse. Le premier consiste en une analyse des transformations de perspectives et d’action au sein d’une équipe de 15 professionnels dentaires ayant participé à la formation continue sur une période de trois mois. L’article décrit, entre autres, une plus grande ouverture, chez certains participants, sur les causes structurelles de la pauvreté et une plus grande sensibilité au vécu au quotidien des personnes prestataires de l’aide sociale. L’article comprend également une exploration des effets paradoxaux dans l’apprentissage, notamment le renforcement, chez certains, de perceptions négatives à l’égard des personnes prestataires de l’aide sociale. Le quatrième article fait état de barrières idéologiques contraignant la transformation des pratiques professionnelles : 1) l’identification à l’idéologie du marché privé comme véhicule d’organisation des soins; 2) l’attachement au concept d’égalité dans les pratiques, au détriment de l’équité; 3) la prédominance du modèle biomédical, contraignant l’adoption de pratiques centrées sur la personne et 4) la catégorisation sociale des personnes prestataires de l’aide sociale. L’analyse des perceptions, mais aussi de l’expérience vécue de ces barrières démontre comment des facteurs systémiques et sociaux influent sur le rapport entre professionnel dentaire et personne prestataire de l’aide sociale. Les conséquences pour la recherche, l’éducation dentaire, le transfert des connaissances, ainsi que pour la régulation professionnelle et les politiques de santé buccodentaire, sont examinées à partir de cette perspective.

Child Health Care in Ireland

The Irish health care system is based on a complex and costly mix of private, statutory, and voluntary provisions. The majority of health care expenditure comes from the state, with a significant proportion of acute hospital care funded from private insurance, but there are relatively high out-of-pocket costs for most service users. There is free access to acute hospital care, but not for primary care, for all children. About 40% of the population have free access to primary care. Universal preventive public health services, including vaccination and immunization, newborn blood spot screening, and universal neonatal hearing screening are free. Major health challenges include poverty, obesity, drug and alcohol use, and mental health. The health care system has been dominated for the last 5 years by the impact of the current recession, which has led to very sharp cuts in health care expenditure. It is unclear if the necessary substantial reform of the system will happen. Government policy calls for a move toward a patient-centered, primary care-led system, but without very substantial transfers of resources and investment in Information and Communication Technology, this is unlikely to occur. The paper has been published as part of an overall report of Child Health in Europe: Diversity of Child Health Care in Europe: A Study of the European Paediatric Association/Union of National European Paediatric Societies and Associations http://www.jpeds.com/issue/S0022-3476(16)X0010-8 . (J Pediatr 2016;177S:S87-106).  

Carers in the welfare state : on informal care and support for carers in Sweden

  The general aim of this dissertation is to describe and analyse patterns of informal care and support for carers in Sweden. One specific aim is to study patterns of informal care from a broad population perspective in terms of types of care and types of carer. A typology of four different care categories based on what carers do revealed that women were much more likely than men to be involved at the ‘heavy end’ of caring, i.e. providing personal care in combination with a variety of other caring tasks. Men were more likely than women to provide some kind of practical help (Study I). Another aim is to investigate which support services are received by which types of informal caregiver. Relatively few informal caregivers in any care category were found to be receiving any kind of support from municipalities or voluntary organizations, for example training or financial assistance (Study II). The same study also examines which kinds of help care recipients receive in addition to that provided by informal carers. It appears that people in receipt of personal care from an informal caregiver quite often also receive help from the public care system, in this case mostly municipal services. However, the majority of those receiving personal, informal care did not receive any help from the public care system or from voluntary organizations or for-profit agencies (Study II). The empirical material in studies I and II comprises survey data from telephone interviews with a random sample of residents in the County of Stockholm aged between 18 and 84. In a number of countries there is a growing interest among social scientists and social policymakers in examining the types of support services that might be needed by people who provide informal care for older people and others. A further aim of the present dissertation is therefore to describe and analyse the carer support that is provided by municipalities and voluntary organizations in Sweden. The dissertation examines whether this support is aimed directly or indirectly at caregivers and discusses whether the Swedish government’s special financial investment in help for carers actually led to any changes in the support provided by municipalities and voluntary organisations. The main types of carer support offered by the municipalities were payment for care-giving, relief services and day care. The chief forms of carer support provided by the voluntary organizations were support groups, training groups, and a number of services aimed primarily at the elderly care recipients (Study III). Patterns of change in municipal carer support could be discerned fairly soon. The Swedish government’s special allocation to municipalities and voluntary organisations appears to have led to an increase in the number of municipalities providing direct support for carers, such as training, information material and professional caregiver consultants. On the other hand, only minor changes could be discerned in the pattern of carer support services provided by the voluntary organizations. This demonstrates stability and the relatively low impact that policy initiatives seem to have on voluntary organizations as providers (Study IV). In studies III and IV the empirical material consists of survey data from mail questionnaires sent to municipalities and voluntary organizations in the County of Stockholm. In the fields of social planning and social work there appears to be a need to clarify the aims of support services for informal carers. Should the support be direct or indirect? Should it be used to supplement or substitute caregivers? In this process of reappraisal it will be important to take the needs of both caregivers and care recipients into account when developing existing and new forms of support. How informal caregivers and care recipients interact with the care system as a whole is undeniably a fertile field for further research.

2016 Quarter 1 Managed Care Ombudsman Program Quarterly Report

he Managed Care Ombudsman Program provides various services including education and information regarding managed care plans, services, care and processes, advocacy and outreach on behalf of members, and appeals assistance and complaint resolution for members needing assistance with resolving issues with their managed care plan or navigating the managed care system. This report provides an update on the following items for the first programmatic quarter (April, May and June 2016): • 1st Quarter Overview • Systemic Trends • Community Partnerships and Outreach • Managed Care Ombudsman Program Administrative Update

The economic rationale for infection control in Australian hospitals

The objective of the present study was to predict the economic consequences of healthcare-acquired infections arising among admissions to Australian acute care hospitals. A quantitative algorithm informed by epidemiological and economic data was developed. All acute care hospitals in Australia were included in the study and the participants included all admissions to general medical and general surgical specialties. The main outcome measures were the numbers of cases of healthcare-acquired infection and bed days lost annually. It was estimated that there are 175 153 (95% credible interval 155 911 : 195 168) cases of healthcare-acquired infection among admissions to Australian hospitals annually, and the extra stay in hospital to treat symptoms accounts for 854 289 bed days (95% credible interval 645 091 : 1 096 244). If rates were reduced by 1%, then 150 158 bed days would be released for alternative uses. This would allow ~38 500 new admissions. Healthcare-acquired infections in patients cause bed blocks in Australian hospitals. The cost-effectiveness of hospital services might be improved by allocating more resources to infection control, releasing beds and allowing new admissions. There exists an opportunity to improve the efficiency of the Australian health care system.

Effects and feasibility of a multi-disciplinary orientation program for newly registered cancer patients : design of a randomised controlled trial

Background Diagnosis and treatment of cancer can contribute to psychological distress and anxiety amongst patients. Evidence indicates that information giving can be beneficial in reducing patient anxiety, so oncology specific information may have a major impact on this patient group. This study investigates the effects of an orientation program on levels of anxiety and self-efficacy amongst newly registered cancer patients who are about to undergo chemotherapy and/or radiation therapy in the cancer care centre of a large tertiary Australian hospital. Methods The concept of interventions for orienting new cancer patients needs revisiting due to the dynamic health care system. Historically, most orientation programs at this cancer centre were conducted by one nurse. A randomised controlled trial has been designed to test the effectiveness of an orientation program with bundled interventions; a face-to-face program which includes introduction to the hospital facilities, introduction to the multi-disciplinary team and an overview of treatment side effects and self care strategies. The aim is to orientate patients to the cancer centre and to meet the health care team. We hypothesize that patients who receive this orientation will experience lower levels of anxiety and distress, and a higher level of self-efficacy. Discussion An orientation program is a common health care service provided by cancer care centres for new cancer patients. Such programs aim to give information to patients at the beginning of their encounter at a cancer care centre. It is clear in the literature that interventions that aim to improve self-efficacy in patients may demonstrate potential improvement in health outcomes. Yet, evidence on the effects of orientation programs for cancer patients on self-efficacy remains scarce, particularly with respect to the use of multidisciplinary team members. This paper presents the design of a randomised controlled trial that will evaluate the effects and feasibility of a multidisciplinary orientation program for new cancer patients.

Innovative approaches to intervention for problem drinking

Purpose of review: To critique the recent literature on telephone, correspondence-based, and computerized interventions for alcohol problems, which enhance or substitute for practitioner-delivered treatments. Recent findings: There is an unmet need for screening, assessment and intervention for alcohol problems, in part because of the difficulty in accessing such treatment within the current health care system. Research on the efficacy of correspondence or electronic (for example Internet-based) interventions is beginning to emerge. In the period 2003–2004 we identified nine acceptability or feasibility studies of these approaches and seven efficacy trials covering a wide range of settings. These modes of intervention are acceptable to patients and the public, and with careful planning, can be implemented in a variety of settings. Treatment trials demonstrate the efficacy of these interventions in reducing hazardous drinking by university students, in delaying initiation of heavy drinking in children and adolescents, and, intriguingly, in addressing insomnia among recovering alcoholics. Summary: There is strong support among potential users for alcohol interventions that employ telephone assistance, written correspondence, and the Internet. These new technologies offer the prospect of increasing the reach of interventions for problem drinking and being cost- effective alternatives or supplements to face-to-face health service delivery.

The experience of China-educated nurses working in Australia : a symbolic interactionist perspective

Transnational nurse migration is a growing phenomenon. However, relatively little is known about the experiences of immigrant nurses and particularly about non-English speaking background nurses who work in more economically developed countries. Informed by a symbolic interactionist framework, this research explored the experience of China-educated nurses working in the Australian health care system. Using a modified constructivist grounded theory method, the main source of data were 46 face to face in-depth interviews with 28 China-educated nurses in two major cities in Australia. The key findings of this research are fourfold. First, the core category developed in this study is reconciling different realities, which inserts a theoretical understanding beyond the concepts of acculturation, assimilation, and integration. Second, in contrast to the dominant discourse which reduces the experience of immigrant nurses to language and culture, this research concludes that it was not just about language and nor was it simply about culture. Third, rather than focus on the negative aspects of difference as in the immigration literature and in the practice of nursing, this research points to the importance of recognising the social value of difference. Finally, the prevailing view that the experience of immigrant nurses is largely negative belies its complexities. This research concludes that it is naïve to define the experience as either good or bad. Rather, ambivalence was the essential feature of the experience and a more appropriate theoretical concept. This research produced a theoretical understanding of the experience of China-educated nurses working in Australia. The findings may not only inform Chinese nurses who wish to immigrate but also contribute to the implementation of more effective support services for immigrant nurses in Australian health care organisations.

Analysis of cardiac and epileptic signals using higher order spectra

The theory of nonlinear dyamic systems provides some new methods to handle complex systems. Chaos theory offers new concepts, algorithms and methods for processing, enhancing and analyzing the measured signals. In recent years, researchers are applying the concepts from this theory to bio-signal analysis. In this work, the complex dynamics of the bio-signals such as electrocardiogram (ECG) and electroencephalogram (EEG) are analyzed using the tools of nonlinear systems theory. In the modern industrialized countries every year several hundred thousands of people die due to sudden cardiac death. The Electrocardiogram (ECG) is an important biosignal representing the sum total of millions of cardiac cell depolarization potentials. It contains important insight into the state of health and nature of the disease afflicting the heart. Heart rate variability (HRV) refers to the regulation of the sinoatrial node, the natural pacemaker of the heart by the sympathetic and parasympathetic branches of the autonomic nervous system. Heart rate variability analysis is an important tool to observe the heart's ability to respond to normal regulatory impulses that affect its rhythm. A computerbased intelligent system for analysis of cardiac states is very useful in diagnostics and disease management. Like many bio-signals, HRV signals are non-linear in nature. Higher order spectral analysis (HOS) is known to be a good tool for the analysis of non-linear systems and provides good noise immunity. In this work, we studied the HOS of the HRV signals of normal heartbeat and four classes of arrhythmia. This thesis presents some general characteristics for each of these classes of HRV signals in the bispectrum and bicoherence plots. Several features were extracted from the HOS and subjected an Analysis of Variance (ANOVA) test. The results are very promising for cardiac arrhythmia classification with a number of features yielding a p-value < 0.02 in the ANOVA test. An automated intelligent system for the identification of cardiac health is very useful in healthcare technology. In this work, seven features were extracted from the heart rate signals using HOS and fed to a support vector machine (SVM) for classification. The performance evaluation protocol in this thesis uses 330 subjects consisting of five different kinds of cardiac disease conditions. The classifier achieved a sensitivity of 90% and a specificity of 89%. This system is ready to run on larger data sets. In EEG analysis, the search for hidden information for identification of seizures has a long history. Epilepsy is a pathological condition characterized by spontaneous and unforeseeable occurrence of seizures, during which the perception or behavior of patients is disturbed. An automatic early detection of the seizure onsets would help the patients and observers to take appropriate precautions. Various methods have been proposed to predict the onset of seizures based on EEG recordings. The use of nonlinear features motivated by the higher order spectra (HOS) has been reported to be a promising approach to differentiate between normal, background (pre-ictal) and epileptic EEG signals. In this work, these features are used to train both a Gaussian mixture model (GMM) classifier and a Support Vector Machine (SVM) classifier. Results show that the classifiers were able to achieve 93.11% and 92.67% classification accuracy, respectively, with selected HOS based features. About 2 hours of EEG recordings from 10 patients were used in this study. This thesis introduces unique bispectrum and bicoherence plots for various cardiac conditions and for normal, background and epileptic EEG signals. These plots reveal distinct patterns. The patterns are useful for visual interpretation by those without a deep understanding of spectral analysis such as medical practitioners. It includes original contributions in extracting features from HRV and EEG signals using HOS and entropy, in analyzing the statistical properties of such features on real data and in automated classification using these features with GMM and SVM classifiers.

Glycosaminoglycan and growth factor mediated murine calvarial cell proliferation

Understanding the complex mechanisms underlying bone remodeling is crucial to the development of novel therapeutics. Glycosaminoglycans (GAGs) localised to the extracellular matrix (ECM) of bone are thought to play a key role in mediating aspects of bone development. The influence of isolated GAGs was studied by utilising in vitro murine calvarial monolayer and organ culture model systems. Addition of GAG preparations extracted from the cell surface of human osteoblasts at high concentrations (5 microg/ml) resulted in decreased proliferation of cells and decreased suture width and number of bone lining cells in calvarial sections. When we investigated potential interactions between the growth factors fibroblast growth factor-2 (FGF2), bone morphogenic protein-2 (BMP2) and transforming growth factor-beta1 (TGFbeta1) and the isolated cell surface GAGs, differences between the two model systems emerged. The cell culture system demonstrated a potentiating role for the isolated GAGs in the inhibition of FGF2 and TGFbeta1 actions. In contrast, the organ culture system demonstrated an enhanced stimulation of TFGbeta1 effects. These results emphasise the role of the ECM in mediating the interactions between GAGs and growth factors during bone development and suggest the GAG preparations contain potent inhibitory or stimulatory components able to mediate growth factor activity.

Exploring health behaviour determinants of ageing Australians with chronic diseases

Background: Chronic disease presents overwhelming challenges to elderly patients, their families, health care providers and the health care system. The aim of this study was to explore a theoretical model for effective management of chronic diseases, especially type 2 diabetes mellitus and/or cardiovascular disease. The assumed theoretical model considered the connections between physical function, mental health, social support and health behaviours. The study effort was to improve the quality of life for people with chronic diseases, especially type 2 diabetes and/or cardiovascular disease and to reduce health costs. Methods: A cross-sectional post questionnaire survey was conducted in early 2009 from a randomised sample of Australians aged 50 to 80 years. A total of 732 subjects were eligible for analysis. Firstly, factors influencing respondents‘ quality of life were investigated through bivariate and multivariate regression analysis. Secondly, the Theory of Planned Behaviour (TPB) model for regular physical activity, healthy eating and medication adherence behaviours was tested for all relevant respondents using regression analysis. Thirdly, TPB variable differences between respondents who have diabetes and/or cardiovascular disease and those without these diseases were compared. Finally, the TPB model for three behaviours including regular physical activity, healthy eating and medication adherence were tested in respondents with diabetes and/or cardiovascular diseases using Structure Equation Modelling (SEM). Results: This was the first study combining the three behaviours using a TPB model, while testing the influence of extra variables on the TPB model in one study. The results of this study provided evidence that the ageing process was a cumulative effect of biological change, socio-economic environment and lifelong behaviours. Health behaviours, especially physical activity and healthy eating were important modifiable factors influencing respondents‘ quality of life. Since over 80% of the respondents had at least one chronic disease, it was important to consider supporting older people‘s chronic disease self-management skills such as healthy diet, regular physical activity and medication adherence to improve their quality of life. Direct measurement of the TPB model was helpful in understanding respondents‘ intention and behaviour toward physical activity, healthy eating and medication adherence. In respondents with diabetes and/or cardiovascular disease, the TPB model predicted different proportions of intention toward three different health behaviours with 39% intending to engage in physical activity, 49% intending to engage in healthy eating and 47% intending to comply with medication adherence. Perceived behavioural control, which was proven to be the same as self-efficacy in measurement in this study, played an important role in predicting intention towards the three health behaviours. Also social norms played a slightly more important role than attitude for physical activity and medication adherence, while attitude and social norms had similar effects on healthy eating in respondents with diabetes and/or cardiovascular disease. Both perceived behavioural control and intention directly predicted recent actual behaviours. Physical activity was more a volitional control behaviour than healthy eating and medication adherence. Step by step goal setting and motivation was more important for physical activity, while accessibility, resources and other social environmental factors were necessary for improving healthy eating and medication adherence. The extra variables of age, waist circumference, health related quality of life and depression indirectly influenced intention towards the three behaviours mainly mediated through attitude and perceived behavioural control. Depression was a serious health problem that reduced the three health behaviours‘ motivation, mediated through decreased self-efficacy and negative attitude. This research provided evidence that self-efficacy is similar to perceived behavioural control in the TPB model and intention is a proximal goal toward a particular behaviour. Combining four sources of information in the self-efficacy model with the TPB model would improve chronic disease patients‘ self management behaviour and reach an improved long-term treatment outcome. Conclusion: Health intervention programs that target chronic disease management should focus on patients‘ self-efficacy. A holistic approach which is patient-centred and involves a multidisciplinary collaboration strategy would be effective. Supporting the socio-economic environment and the mental/ emotional environment for older people needs to be considered within an integrated health care system.

Predictive factors of contact lens case contamination

PURPOSE: To examine the relationship between contact lens (CL) case contamination and various potential predictive factors. METHODS: 74 subjects were fitted with lotrafilcon B (CIBA Vision) CLs on a daily wear basis for 1 month. Subjects were randomly assigned one of two polyhexamethylene biguanide (PHMB) preserved disinfecting solutions with the corresponding regular lens case. Clinical evaluations were conducted at lens delivery and after 1 month, when cases were collected for microbial culture. A CL care non-compliance score was determined through administration of a questionnaire and the volume of solution used was calculated for each subject. Data was examined using backward stepwise binary logistic regression. RESULTS: 68% of cases were contaminated. 35% were moderately or heavily contaminated and 36% contained gram-negative bacteria. Case contamination was significantly associated with subjective dryness symptoms (OR 4.22, CI 1.37–13.01) (P<0.05). There was no association between contamination and subject age, ethnicity, gender, average wearing time, amount of solution used, non-compliance score, CL power and subjective redness (P>0.05). The effect of lens care system on case contamination approached significance (P=0.07). Failure to rinse the case with disinfecting solution following CL insertion (OR 2.51, CI 0.52–12.09) and not air drying the case (OR 2.31, CI 0.39–13.35) were positively correlated with contamination; however, did not reach statistical significance. CONCLUSIONS: Our results suggest that case contamination may influence subjective comfort. It is difficult to predict the development of case contamination from a variety of clinical factors. The efficacy of CL solutions, bacterial resistance to disinfection and biofilm formation are likely to play a role. Further evaluation of these factors will improve our understanding of the development of case contamination and its clinical impact.