Integrable Quantum Field Theories, in the Bulk and with a Boundary

This thesis considers massive field theories in 1+1 dimensions known as affine Toda quantum field theories. We first consider the boundary sine-Gordon model, deriving a complete picture of the boundary bound state structure for general integrable boundary conditions, and then more general ATFTs in the bulk, discovering a "generalised bootstrap" equation which explicitly encodes the Lie algebra into the S-matrix. This last is related to a number of S-matrix identities, as well as a generalisation of the idea that the conserved charges of the theory form an eigenvector of the Cartan matrix.Comment: Ph.D. thesis, Durham, LaTeX, 112 pages, 6 eps figures, uses fancyheadings.st

Seventh time lucky-A case report of multiple radiofrequency ablations for right ventricular outflow tract tachycardia

Right ventricular outflow tachycardia initially refractory to radiofrequency ablation may be successfully treated after radiofrequency ablation at multiple sites. Repeated radiofrequency ablations as well as cooperation across borders with referral to an international center of excellence may be required in complicated casesPeer reviewe

Clinical Indications for Therapeutic Cardiac Devices

Both technology and clinical indications have changed since the first cardiac devices. Choosing the right therapy, or abstaining from it, is the key to good clinical management. Pacemakers effectively reduce symptoms of bradycardia, prevent syncope in patients with sick sinus syndrome, and reduce mortality in high-degree atrioventricular block. Cardiac resynchronization therapy improves symptoms and survival in heart failure patients with reduced ejection fraction and ventricular dyssynchrony. Implantable cardioverter defibrillators terminate life-threatening ventricular arrhythmias and are indicated for the prevention of sudden cardiac death, either as secondary prevention in survivors of ventricular fibrillation or ventricular tachycardia with hemodynamic compromise or as primary prevention due to heart failure with reduced ejection fraction or other miscellaneous diseases. More recently, leadless pacemakers and subcutaneous implantable cardioverter defibrillators have been developed as alternatives in specific conditions

Dynamics of Magma Mixing in Partially Crystallized Magma Chambers: Textural and Petrological Constraints from the Basal Complex of the Austurhorn Intrusion (SE Iceland)

The Tertiary Austurhorn intrusive complex in SE Iceland represents an exhumed magma chamber that has recorded an extensive history of magma mixing and mingling. The basal part of the intrusion consists predominantly of granophyres that have been intensively and repeatedly intruded by more mafic magma. This association of granophyres, basic and hybrid rocks at Austurhorn is referred to in the literature as a ‘net-veined' complex, but field relations suggest a much more complex emplacement history. Here we present petrological and physical constraints on the various processes that resulted in magma mixing and mingling and the formation of different generations of hybrid rocks at Austurhorn. The complexity of the mixing and mingling processes increases towards the inferred centre of the intrusion, where chaotic hybrid rocks dominate the exposed lithology. Complex cross-cutting relations between different hybrid generations strongly suggest multiple magma injection and reheating events in the basal part of the shallow magma chamber. Model calculations employing distribution coefficients based on rare earth element concentrations reveal that early stage hybrid magma generations formed by pure endmember mixing between felsic and mafic magma with about 10% mafic fraction in the hybrids. With repeated injections of mafic magma into the base of the magma chamber, the intruding magma interacted to a greater extent with pre-existing hybrids. This led to the formation of hybrid magma compositions that are shifted towards the mafic endmember over time, with up to 30% of the mafic fraction in the hybrids. These mixing processes are recorded in the zonation patterns of clinopyroxene and plagioclase phenocrysts; the latter have been divided into four main groups by cross-correlation analysis. Melt viscosity calculations were performed to constrain the possible conditions of magma mixing and the results indicate that the interaction of the contrasting magmas most probably occurred at temperatures of approximately 1000°C up to 1120°C. This suggests that the initiation of effective magma mixing requires local superheating of the felsic magmas, thereby confining the process to areas of localized, substantial mafic magma injectio

Ischemic Cardiomyopathy: Contemporary Clinical Management

Ischemic cardiomyopathy, disease of the heart muscle due to coronary artery disease, is the most common cardiomyopathy. It is often difficult to discern the etiology of heart failure, and often there are multiple underlying causes. Ischemic cardiomyopathy most often presents with a dilated morphology with wall motion defects and a history of previous myocardial infarction or confirmed coronary artery disease. Mechanisms of myocardial depression in ischemia are necrosis of myocardial cells resulting in irreversible loss of function or reversible damage, either short term through myocardial stunning or long term through hibernation. In ischemic cardiomyopathy, echocardiography may be extended with stress testing or other imaging modalities such as myocardial scintigraphy and cardiac magnetic resonance tomography. Coronary angiography is often considered a gold standard; however, other modalities such as positron emission tomography can be needed to detect small vessel disease. Cardiac revascularization, through percutaneous coronary intervention and coronary artery bypass grafting, both in acute coronary syndrome and in stable coronary artery disease, relieves symptoms and improves prognosis. Therapy should aspire to treat ischemia, arrhythmias in addition to heart failure management, which includes device therapy with cardiac resynchronization therapy, implantable cardioverter defibrillators, and mechanical support as bridging or destination therapy in end-stage disease

Cardiac Implantable Electronic Device-Related Infections

The use of cardiac devices, that is, pacemakers and implantable cardioverter defibrillators, has increased, and the incidence will likely continue to increase due to an aging population with associated risk factors. Unfortunately, this implies an increasing number of complications, including infections. Cardiac device-related infection is a dreaded complication causing both increased morbidity and mortality, and considerable costs. Because of the presence of a foreign body in subcutaneous tissue, vasculature, and the heart, patients with cardiac device systems are at increased risk of endocarditis due to microbial agents. In general, an infected device system should be removed in its entirety. The timing of reimplantation varies due to indication and severity of the infection. Furthermore, the explant procedure may be complicated and should be performed by an experienced team including facilities to handle life-threatening complications. The subcutaneous implantable cardioverter defibrillator or leadless pacemaker can serve as an option in selected cases. This chapter will describe clinical aspects of cardiac device-related infections

Synthesis of Universal Workplace Design in Assembly-A Case Study

To form an inclusive and sustainable society, workplace design that can be used by different individuals, regardless of sex, language, background, and body function variations is needed. Such workplaces can also give economic benefits to companies if they provide a more accessible, safer, more productive and error proofed working environment. This aim of this paper is to evaluate a universal design concept developed at a company aiming at providing an \u27easy job\u27-workplace design for manual industrial operations. The study investigated key factors from 8 interviews and compared it to theoretical constructs such as WHO\u27s ICIDH-2. A synthesis was formed that included the following factors: personal factors, environmental factors and outcomes of universal work. The study has resulted in new insights regarding universal workplace design and the vision is that the synthesis can be used by other production companies that want to increase the universal design in assembly work