Epidemiological aspects of sarcoidosis : risk factors and long-term consequences

Sarcoidosis is a systemic inflammatory disease of unknown etiology in which granulomatous lesions form mostly in the lungs and the lymphatic system of patients. Although more than a century has passed since sarcoidosis was first described, our understanding of its etiology and clinical course is limited. That is because epidemiological studies on large and representative patient cohorts have been lacking. The scope of this thesis was to examine aspects of sarcoidosis epidemiology using a linkage of large, nationwide health and administrative databases from Sweden complemented by clinical data. Six individual studies are included in this thesis; the first two dealt with risk factors for sarcoidosis, namely familial and infectious disease, and the rest with long-term debilitating patient outcomes: mortality, infection, and heart failure. In Study I, a case-control-family study, we estimated familial relative risks and the heritability of sarcoidosis. We found that having first-degree relatives with sarcoidosis increased the risk of being diagnosed with the disease by more than threefold. 39% of the susceptibility to sarcoidosis in the Swedish population was estimated to be attributable to additive genetic effects; the rest was due to non-shared (among siblings) environmental factors. Study II was a case-control study in which we estimated relative risks of sarcoidosis associated with having a history of infectious disease diagnoses. We showed that infectious diseases (commonly upper respiratory and genitourinary) diagnosed before sarcoidosis diagnosis were associated with a small increased risk of sarcoidosis in the future, a relative risk that did not vary markedly by latency period between infectious disease ascertainment and sarcoidosis diagnosis. These small relative risks could be easily explained away in analyses designed to test the robustness of these associations in the presence of reverse causation bias. In Study III, a cohort study, we followed individuals with sarcoidosis and general population comparators for all-cause death. We showed that there was an overall 61% increased risk of death associated with sarcoidosis. Stratification by treatment status around the time of sarcoidosis diagnosis approximating disease severity revealed a 2.3-fold higher risk of all-cause mortality compared to the general population in those treated while no risk increase was observed for untreated patients with sarcoidosis. Similarly, in Study IV, we followed individuals for a first or recurrent serious (hospitalized) infections. We observed a 1.8-fold higher risk of serious infection in sarcoidosis compared to the general population, which was even higher during the first two years since diagnosis and in individuals who were treated with an immunosuppressant around sarcoidosis diagnosis likely due to more severe or progressive disease at the time. In Study V, a target trial emulation, we compared six-month risks of infectious disease in initiators of methotrexate compared to azathioprine, two second line treatments for sarcoidosis. Six months after treatment initiation, a 43% lower risk of infectious disease was observed in the methotrexate compared to the azathioprine group. Study VI was a cohort study in which we examined the relative risk of heart failure and its predictors in sarcoidosis. We found a 2.4-fold increased relative risk of heart failure associated with sarcoidosis that was higher during the first two years since sarcoidosis diagnosis and in individuals without a history of ischemic heart disease. Diabetes, atrial fibrillation, and other arrhythmias were the strongest clinical predictors of heart failure diagnosis in sarcoidosis. Overall, findings from studies on risk factors in this thesis suggest that familial disease and genetics are important in sarcoidosis, albeit a larger contribution to the etiology of sarcoidosis is likely due to environmental factors. Among environmental factors, clinically identifiable infectious diseases are unlikely to be strong risk factors for sarcoidosis diagnosis. Future molecular and epidemiological studies on environmental triggers of sarcoid inflammation and disease should consider the issue of reverse causality owing to long preclinical disease in some patients. Studies on long-term patient outcomes in this thesis showed that sarcoidosis is not a ‘benign’ disease. Therefore, our quest to identify effective interventions and groups of patients to target should continue. If applied early, these measures can help alleviate some of the risks related to infection and heart failure, and improve life expectancy, especially in patients with severe or chronic disease

Development and Application of an Analytical Framework for the Measurement of Customer Service Quality in the Banking Industry of Cyprus

The main objectives of this study are to demonstrate the significance of customer service quality in the banking sector of Cyprus in order to enable managers in banking organisations to identify the determinants of customer perceptions of service quality and ultimately to provide a method to measure the levels of service quality offered. Therefore, the objectives of this thesis are: • To evaluate the SERVQUAL model and assess whether it can be applied in the context of the Cypriot banking industry, and consequently establish a reliable and valid service quality measurement instrument for Cypriot banks, and • To identify the level of service from banks in Cyprus and detect ways to improve the service quality offered. This study evaluates SERVQUAL dimensions, and more specifically the perceptions side of the instrument, and modifies it through an extensive and in-depth analysis of the literature review published on the topic of service quality and through interviews with bank experts and quality specialists so as to assess its applicability to the banking industry in Cyprus. As a result of this analysis, a modified version of the perceptions’ side of SERVQUAL was constructed as a measurement scale of service quality in the banking sector of Cyprus. Data were collected through customer surveys conducted outside bank branches. Subsequently, the collected data were analysed through tools such as factor analysis, multiple regression analysis, and internal consistency measurement. This analysis helped to prove the validity and reliability of the modified instrument used to measure service quality and revealed the dimensional structure of the service quality construct in the Cypriot banking sector. The major findings of this study suggest a four-dimensional construct derived from 23 items in the questionnaire. These dimensions are employee proficiency, convenience, professionalism and assurance. All four factors are positive and significant predictors of service quality. This result is different from the SERVQUAL and the SERVPERF models as both indicate five dimensions composed of 22 items. The reliability and validity of the scale(s) in this study were fully supported. These results lead to several implications for both researchers and practitioners. For theorists, the results of this study can be used as foundations for further studies, for questionnaire scale development, to further support the use of a single scale and to raise the issue of the non-existence of the ‘tangibles’ dimension, which is not fully discussed in the literature and should be tested in future studies as well. For managers and practitioners this study offers much support for the importance of employees and for a continuous investment in service quality programmes. It also suggests incorporating service quality measurement into branch performance measurement. Finally, the results obtained in this study pose significant challenges to managers and support the idea that practitioners should have a comprehensive view of service quality in banking organizations to accurately measure customer perceptions of service quality

Cyprus and the Rule of Law

This article addresses two broad questions. First, whether the Turkish government, by its 1974 invasion and occupation of over a third of Cyprus using American-supplied arms, violated United States laws, bilateral agreements between Turkey and the United States under those laws, and any international charters, treaties and conventions. Second, whether the government of the United States, through the actions of Secretary of State Henry A. Kissinger, violated its own laws in connection with Turkey\u27s invasion and occupation of Cyprus. The last section of the article briefly discusses a future course of action

Πλοήγηση κινούμενου ρομπότ σε άγνωστο περιβάλλον προς ένα προκαθορισμένο στόχο

90 σ.Η παρούσα διπλωματική εργασία περιγράφει μια υλοποίηση ενός συστήματος αλληλεπίδρασης ανθρώπου υπολογιστή για ευφυή ρομπότ. Αποσκοπεί στο να προσφέρει την ικανότητα σε ένα κινούμενο ρομπότ εσωτερικού χώρου να κατανοήσει και να εκτελέσει οδηγίες πλοήγησης δοσμένες σε μια ψευδο-ανθρώπινη γλώσσα. Το ρομπότ τοποθετείται σε άγνωστο περιβάλλον εσωτερικού χώρου και του δίνονται οδηγίες όπως "Πήγαινε στο τρίτο γραφείο δεξιά". Για να επιτύχει το σκοπό του, το ρομπότ πρέπει να έχει τη δυνατότητα να φτιάξει ένα χάρτη του περιβάλλοντος και να προσδιορίσει τη θέση του μέσα σε αυτό. Για το σκοπό αυτό χρησιμοποιούνται τεχνικές Simultaneous Localisation And Mapping (SLAM). Δύο σημαντικές καινοτόμες προκλήσεις αντιμετωπίζονται. Αρχικά, η πλοήγηση προς ένα στόχο διαμέσου ενός άγνωστου χάρτη, και κατά δεύτερον, το πόσο χρήσιμος και ενημερωτικός είναι ο χάρτης. Ο κύριος στόχος των υφιστάμενων τεχνικών πλοήγησης είναι να οδηγήσουν το ρομπότ προς την άγνωστη περιοχή του χάρτη ώστε να ελαχιστοποιήσουν το περιβάλλον που δεν έχει επισκευθεί ακόμα. Αυτό δεν είναι αρκετό αν το ρομπότ πρέπει να κινηθεί προς ένα προκαθορισμένο στόχο. Για να επιτευχθεί αυτού του είδους η συμπεριφορά, έχει επανασχεδιαστεί μια υφιστάμενη τεχνική πλοήγησης. Επιπρόσθετα, το ρομπότ θα πρέπει να αναγνωρίσει τις οντότητες που υποδηλώνονται από τις οδηγίες που δίνει ο άνθρωπος. Για να επιτευχθεί αυτό, δημιουργείται ένας χάρτης οντοτήτων όπως πόρτα, καρέκλα, κιβώτιο κλπ. και δίνεται στο ρομπότ. Για να αναγνωριστούν αυτές οι οντότητες, θα μπορούσαν να χρησιμοποιηθούν τεχνικές αναγνώρισης προτύπων. Το αποτέλεσμα είναι ένας χάρτης αντικειμένων που μπορεί να χρησιμοποιηθεί όχι μόνο για πλοήγηση, αλλά και για καλύτερη απεικόνιση του χάρτη.This thesis project describes an implementation of a Human Computer Interaction (HCI) system for intelligent mobile robots. It aims to provide the ability to indoor mobile robots to understand and execute direction orders described in a pseudo-human language. The robot is positioned in an unknown indoor environment and it is given directions like ”Go to the third office on your right”. To achieve that, the robot should be able to create a map of its environment and localise itself in the map. Thus, Simultaneous Localisation And Mapping (SLAM) techniques are used. Two key novel challenges are confronted. Firstly, the navigation towards a target in a yet unknown map, and secondly, how informative and useful the map is. The main objective of existing navigation techniques, is to drive the robot towards the unknown area of the map in order to minimise the yet unseen environment. That is not enough if the robot must move towards a predefined target. In order to achieve this kind of behaviour, an existing navigation technique is augmented. Secondly, the robot should be able to recognise entities that signify the way-points given by the human. To cope with that, a map of entities like door, chair, box, etc. is created and provided to to the robot. To identify these entities, pattern recognition techniques may be employed. The result is a map of objects that can be used not only for navigation and path planning, but also for a better illustration of the actual map.Χαράλαμπος Μ. Ρωσσίδη

Particle Swarm Optimization—An Adaptation for the Control of Robotic Swarms

Particle Swarm Optimization (PSO) is a numerical optimization technique based on the motion of virtual particles within a multidimensional space. The particles explore the space in an attempt to find minima or maxima to the optimization problem. The motion of the particles is linked, and the overall behavior of the particle swarm is controlled by several parameters. PSO has been proposed as a control strategy for physical swarms of robots that are localizing a source; the robots are analogous to the virtual particles. However, previous attempts to achieve this have shown that there are inherent problems. This paper addresses these problems by introducing a modified version of PSO, as well as introducing new guidelines for parameter selection. The proposed algorithm links the parameters to the velocity and acceleration of each robot, and demonstrates obstacle avoidance. Simulation results from both MATLAB and Gazebo show close agreement and demonstrate that the proposed algorithm is capable of effective control of a robotic swarm and obstacle avoidance

The dynamics of interacting multi-pulses in the one-dimensional quintic complex Ginzburg-Landau equation

We formulate an effective numerical scheme that can readily, and accurately, calculate the dynamics of weakly interacting multi-pulse solutions of the quintic complex Ginzburg-Landau equation (QCGLE) in one space dimension. The scheme is based on a global centre-manifold reduction where one considers the solution of the QCGLE as the composition of individual pulses plus a remainder function, which is orthogonal to the adjoint eigenfunctions of the linearised operator about a single pulse. This centre-manifold projection overcomes the difficulties of other, more orthodox, numerical schemes, by yielding a fast-slow system describing 'slow' ordinary differential equations for the locations and phases of the individual pulses, and a 'fast' partial differential equation for the remainder function. With small parameter $\epsilon=e^{-\lambda_r d}$ where $\lambda_r$ is a constant and $d>0$ is the pulse separation distance, we write the fast-slow system in terms of first-order and second-order correction terms only, a formulation which is solved more efficiently than the full system. This fast-slow system is integrated numerically using adaptive time-stepping. Results are presented here for two- and three-pulse interactions. For the two-pulse problem, cells of periodic behaviour, separated by an infinite set of heteroclinic orbits, are shown to 'split' under perturbation creating complex spiral behaviour. For the case of three pulse interaction a range of dynamics, including chaotic pulse interaction, are found. While results are presented for pulse interaction in the QCGLE, the numerical scheme can also be applied to a wider class of parabolic PDEs.Comment: 33 page

Cost Optimization of Ice Distribution

Two questions regarding minimizing fuel costs while delivering ice along a pre-set route are tackled. The first question is when demand exceeds the load of a single truck, so that a second truck of ice has to be taken to some point of the route for the driver/salesman to continue with that for the rest of the route: Is it better: 1) for the first truck to deliver starting from the costumer nearest to the base, or 2) for the first truck to start the delivery from the last costumer (the most distant from the base)? We show that the second strategy was better for the particular data looked at, and we have the basis of an algorithm for deciding which strategy is the better for a given delivery schedule. The second question concerns how best to modify a regular sales route when an extra delivery has to be made. Again, the basis for an algorithm to decide how to minimize fuel costs is derived