Artificial opal photonic crystals and inverse opal structures - fundamentals and applications from optics to energy storage

Photonic crystals (PhCs) influence the propagation of light by their periodic variation in dielectric contrast or refractive index. This review outlines the attractive optical qualities inherent to most PhCs namely the presence of full or partial photonic band gaps and the possibilities they present towards the inhibition of spontaneous emission and the localization of light. Colloidal self-assembly of polymer or silica spheres is one of the most favoured and low cost methods for the formation of PhCs as artificial opals. The state of the art in growth methods currently used for colloidal self-assembly are discussed and the use of these structures for the formation of inverse opal architectures is then presented. Inverse opal structures with their porous and interconnected architecture span several technological arenas - optics and optoelectronics, energy storage, communications, sensor and biological applications. This review presents several of these applications and an accessible overview of the physics of photonic crystal optics that may be useful for opal and inverse opal researchers in general, with a particular emphasis on the recent use of these three-dimensional porous structures in electrochemical energy storage technology. Progress towards all-optical integrated circuits may lie with the concepts of the photonic crystal, but the unique optical and structural properties of these materials and the convergence of PhC and energy storage disciplines may facilitate further developments and non-destructive optical analysis capabilities for (electro)chemical processes that occur within a wide variety of materials in energy storage research.

Police accountability in Ireland: an analysis of the problems posed by the legal, constitutional and political dimensions and how they might be addressed

The concept of police accountability is not susceptible to a universal or concise definition. In the context of this thesis it is treated as embracing two fundamental components. First, it entails an arrangement whereby an individual, a minority and the whole community have the opportunity to participate meaningfully in the formulation of the principles and policies governing police operations. Second, it presupposes that those who have suffered as victims of unacceptable police behaviour should have an effective remedy. These ingredients, however, cannot operate in a vacuum. They must find an accommodation with the equally vital requirement that the burden of accountability should not be so demanding that the delivery of an effective police service is fatally impaired. While much of the current debate on police accountability in Britain and the USA revolves around the issue of where the balance should be struck in this accommodation, Ireland lacks the very foundation for such a debate as it suffers from a serious deficit in research and writing on police generally. This thesis aims to fill that gap by laying the foundations for an informed debate on police accountability and related aspects of police in Ireland. Broadly speaking the thesis contains three major interrelated components. The first is concerned with the concept of police in Ireland and the legal, constitutional and political context in which it operates. This reveals that although the Garda Siochana is established as a national force the legal prescriptions concerning its role and governance are very vague. Although a similar legislative format in Britain, and elsewhere, have been interpreted as conferring operational autonomy on the police it has not stopped successive Irish governments from exercising close control over the police. The second component analyses the structure and operation of the traditional police accountability mechanisms in Ireland; namely the law and the democratic process. It concludes that some basic aspects of the peculiar legal, constitutional and political structures of policing seriously undermine their capacity to deliver effective police accountability. In the case of the law, for example, the status of, and the broad discretion vested in, each individual member of the force ensure that the traditional legal actions cannot always provide redress where individuals or collective groups feel victimised. In the case of the democratic process the integration of the police into the excessively centralised system of executive government, coupled with the refusal of the Minister for Justice to accept responsibility for operational matters, project a barrier between the police and their accountability to the public. The third component details proposals on how the current structures of police accountability in Ireland can be strengthened without interfering with the fundamentals of the law, the democratic process or the legal and constitutional status of the police. The key elements in these proposals are the establishment of an independent administrative procedure for handling citizen complaints against the police and the establishment of a network of local police-community liaison councils throughout the country coupled with a centralised parliamentary committee on the police. While these proposals are analysed from the perspective of maximising the degree of police accountability to the public they also take into account the need to ensure that the police capacity to deliver an effective police service is not unduly impaired as a result.

Surfactant-mediated variation of band-edge emission in CdS nanocomposites

The optical-structural characteristics of the direct optical band-gap semiconducting series of surfactant template-mediated laminar (CdS)x(CdCl2)y(CnH2n+4N)z nanocomposites are reported. X-ray diffraction measurements of the nanocomposites exhibited interlaminar distances in the range 2.9-3.6 nm with observations of eighth order {0 0 l} diffraction planes indicative of a high degree of laminarity and crystallographic order. Diffuse reflectance measurements have determined that the profile of their emission spectrum is that of a direct band-gap with absorption edges in the range 2.11-2.40 eV, depending on the CdS mole fraction in the nanocomposite. Photoluminescence (PL) excitation and time-resolved PL spectroscopies give an estimate of the maximum relative absorbance of the nanocomposites at ∼420 nm while the minimum was observed at ∼560 nm. The main emission was observed at ∼700 nm with emission from doubly ionized sulphur vacancies observed at ∼615 nm at room temperature. The CdS-containing nanocomposite is thus a surfactant-mediated modular system with variable band-gap energy emission.

An examination of the role of the sports and exercise medicine specialist in Ireland- from epidemiology to treatment

The expansion of the specialty of sports and exercise medicine (SEM) is a relatively recent development in the medical community and the role of the SEM specialist continues to evolve and develop. The SEM specialist is ideally placed to care for all aspects of physical activity not only in athletes but also in the general population. As an advocate for physical activity the SEM specialist plays a broad role in advising safe effective sports and recreation participation; screening for disease related to sports participation; examining and contributing to the evidence behind treatment strategies and evaluating any potential negative impact of sports injury prevention measures. In this thesis I will demonstrate the breadth of the role the Sports and Exercise Medicine Specialist from epidemiology to in-depth examination of treatment strategies. In Chapter 2, I examined the epidemiology of sports and recreation related injury (SRI) in Ireland, an area that has previously been poorly studied. We report on 3,172 SRI (14% of total presentations) presentations to the ED over 6 months. Paediatric patients (4-16 yrs) were over represented comprising 39.9% of all SRI presentation compared to 16% of total ED presentations and 18% of the general population. These injuries were serious (32% fractures) and though 49% of injuries occurred during organised competition/practice, 41.5% occurred during recreation-most often at home. In Chapter 3, I examined risk factors associated with hand injury in hurling. The previous chapter highlighted the importance of a firm evidence base underpinning treatment strategies. When measures to improve welfare are introduced not only must potential benefits be measured, so too must potential unwanted adverse outcomes. In this study I examined a cohort of adult hurlers who had presented to the ED with a hurling related injury in order to highlight the variables associated with hand injury in this population. I found the athletes who wore a helmet were far more likely (OR 3.15 95% CI (1.51-6.56) p= 0.002) to suffer a hand injury than athletes who did not. Very few of those interviewed (4.9%) used hand protection compared to 65% who used helmet and faceguard. The introduction of the helmet and faceguard in hurling has undeniably decreased the incidence of head and face injury in hurling. However in tandem with this intervention several observational studies have demonstrated an increase in the occurrence of hurling related hand injuries. This study highlights the importance of being cognisant of unanticipated or unintended consequences when implementing a new treatment or intervention. In Chapter 4, I examined the role of population screening as applied to sport and exercise. This is a controversial area –cardiac screening in the exercising population has been the subject of much debate. Specifically I define the prevalence of exercise induced bronchoconstriction (EIB) using a specifically designed sports specific field-testing protocol. In this study I found almost a third (29%) of a full international professional rugby squad had confirmed asthma or EIB, as compared with 12-15% of the general population. Despite regular medical screening, 5 ‘new’ untreated cases (12%) were elicited by the challenge test and in the group already on treatment for asthma/EIB; over 50% still displayed EIB. In Chapter 5, I examined the evidence supporting current treatment options for iliotibial band friction syndrome (ITBFS). The practice of sports medicine has traditionally been ‘eminence based’ rather than ‘evidence based’. This may be problematic as some of these practices are based upon flawed principles- for example the treatment of iliotibial band friction syndrome (ITBFS). In this chapter, using cadaveric and biomechanical studies I expand upon the growing base of evidence clarifying the anatomy and biomechanics of the area-thereby re-examining the principles on which current treatments are based. The role of the SEM specialist is broad; we chose to examine specific examples of some of the roles that they execute. An understanding of the epidemiology of SRI presenting to the ED has implications for individual patients, sports governing bodies and health resource utilisation. Population screening is an important tool in health promotion and disease prevention in the general population. Screening in SEM may have similar less well-recognised benefits. The SEM specialist needs to be conversant in screening for medical conditions concerning physical activity. A comprehensive understanding of the pathophysiology of a disease is required for its diagnosis and treatment. Due to the ongoing evolution of SEM many treatments are eminence-based rather than evidence‐based practice. Continued re-examination of the fundamentals of current practice is essential. An awareness of potential unwanted side effects is essential prior to the introduction of any new treatment or intervention. The SEM specialist is ideally placed to advise sports governing bodies on these issues prior to and during their implementation.