Recent advance in health and technology has made mobile apps a viable approach to delivering behavioral interventions in areas including physical activity encouragement, smoking cessation, substance abuse prevention, and mental health management. Due to the chronic nature of most of the disorders and heterogeneity among mobile users, delivery of the interventions needs to be sequential and tailored to individual needs. We operationalize the sequential decision making via a policy that takes a mobile user's past usage pattern and health status as input and outputs an app/intervention recommendation with the goal of optimizing the cumulative rewards of interest in an indefinite horizon setting. There is a plethora of reinforcement learning methods on the development of optimal policies in this case. However, the vast majority of the literature focuses on studying the convergence of the algorithms with infinite amount of data in computer science domain. Their performances in health applications with limited amount of data and high noise are yet to be explored. Technically the nature of sequential decision making results in an objective function that is non-smooth (not even a Lipschitz) and non-convex in the model parameters. This poses theoretical challenges to the characterization of the asymptotic properties of the optimizer of the objective function, as well as computational challenges for optimization. This problem is especially exacerbated with the presence of high dimensional data in mobile health applications. In this dissertation we propose a regularized greedy gradient Q-learning (RGGQ) method to tackle this estimation problem. The optimal policy is estimated via an algorithm which synthesizes the PGM and the GGQ algorithms in the presence of an L₁ regularization, and its asymptotic properties are established. The theoretical framework initiated in this work can be applied to tackle other non-smooth high dimensional problems in reinforcement learning.

La presente tesis propone el diseño de un sistema que trabaja con señales electro oculográficas para luego procesarlas e interpretarlas con la finalidad de que el usuario pueda realizar trabajos con el ordenador usando únicamente el músculo ocular. El problema que se resuelve tiene una inclinación técnico ingenieril, ya que busca subsanar las debilidades y cubrir los aspectos no tocados por el estado del arte presente, para finalmente diseñar un equipo electrónico que permita la interacción de un usuario con un computador bajo las necesidades de una persona con discapacidad en los miembros superiores. El dispositivo diseñado está compuesto por un circuito capaz de adquirir por medio de electrodos la señal EOG de una persona, procesarla y analizarla para conocer la forma de onda y posteriormente interpretarla y enviar un carácter de reconocimiento de forma de onda usando un bluetooth a una computadora con la que se debe aparear con anterioridad. Esta computadora constará de un software que se diseñó en la presente tesis el será capaz de interpretar los caracteres recibidos y realizar funciones de movimiento y pulsación de un mouse, además de escritura usando un teclado virtual. Para validar el dispositivo diseñado se hicieron pruebas con 16 personas, de las cuales 14 fueron personas sin discapacidad en los miembros superiores y 2 de ellas sí. No se trabajaron con pacientes de un centro de salud específico, se realizaron pruebas con personas contactadas por médicos y fisioterapeutas entre los cuales se encuentran algunos que trabajan para la UPC los cuales brindaron su incondicional apoyo para la validación y pruebas con los pacientes a su cargo. Los resultados obtenidos en las pruebas realizadas muestran que de un grupo de 16 personas la eficiencia en el reconocimiento de la forma de onda de un doble parpadeo es del 92.9%, del parpadeo – mirada arriba y parpadeo – mirada abajo 88.4% y del parpadeo prolongado 93%. El valor trazado como objetivo fue 80% a más, por lo que se logra cumplir con ello. / The present thesis proposes the design of a system that works with electro-occupational signals and then processes and interprets them so that the user can work with the computer using only the ocular muscle. The problem that is solved has a technical engineering inclination, since it seeks to correct the weaknesses and cover the aspects not touched by the present state of the art, to finally design an electronic equipment that allows the interaction of a user with a computer under the needs of a person with a disability in the upper limbs. The designed device is composed of a circuit capable of acquiring through electrodes the EOG signal of a person, processing and analyzing it to know the waveform and then interpret it and send a waveform recognition character using a bluetooth to a computer with which it must be paired in advance.  This computer will consist of software that was designed in the present thesis and will be able to interpret the received characters and perform functions of moving and pressing a mouse, as well as writing using a virtual keyboard. In order to validate the designed device, tests were made with 16 people, of which 14 were people without disabilities in the upper limbs and 2 of them were. We did not work with patients from a specific health centre, but tested with people contacted by doctors and physiotherapists, including some who work for the UPC, who provided their unconditional support for validation and testing with the patients in their care. The results obtained in the tests carried out show that out of a group of 16 people the efficiency in the recognition of the waveform of a double blink is 92.9%, of the blink - look up and blink - look down 88.4% and of the prolonged blink 93%. The target value was 80% to more, so it is achieved. / Tesis

This thesis explores various detailed improvements to semi-supervised learning (using labelled data to guide clustering or classification of unlabelled data) with fuzzy c-means clustering (a ‘soft’ clustering technique which allows data patterns to be assigned to multiple clusters using membership values), with the primary aim of creating a semi-supervised fuzzy clustering algorithm that shows good performance on real-world data. Hence, there are two main objectives in this work. The first objective is to explore novel technical improvements to semi-supervised Fuzzy c-means (ssFCM) that can address the problem of initialisation sensitivity and can improve results. The second objective is to apply the developed algorithm on real biomedical data, such as the Nottingham Tenovus Breast Cancer (NTBC) dataset, to create an automatic methodology for identifying stable subgroups which have been previously elicited semi-manually. Investigations were conducted into detailed improvements to the ss-FCM algorithm framework, including a range of distance metrics, initialisation and feature selection techniques and scaling parameter values. These methodologies were tested on different data sources to demonstrate their generalisation properties. Evaluation results between methodologies were compared to determine suitable techniques on various University of California, Irvine (UCI) benchmark datasets. Results were promising, suggesting that initialisation techniques, feature selection and scaling parameter adjustment can increase ssFCM performance. Based on these investigations, a novel ssFCM framework was developed, applied to the NTBC dataset, and various statistical and biological evaluations were conducted. This demonstrated highly significant improvement in agreement with previous classifications, with solutions that are biologically useful and clinically relevant in comparison with Sorias study [141]. On comparison with the latest NTBC study by Green et al. [63], similar clinical results have been observed, confirming stability of the subgroups. Two main contributions to knowledge have been made in this work. Firstly, the ssFCM framework has been improved through various technical refinements, which may be used together or separately. Secondly, the NTBC dataset has been successfully automatically clustered (in a single algorithm) into clinical sub-groups which had previously been elucidated semi-manually. While results are very promising, it is important to note that fully, detailed validation of the framework has only been carried out on the NTBC dataset, and so there is limit on the general conclusions that may be drawn. Future studies include applying the framework on other biomedical datasets and applying distance metric learning into ssFCM. In conclusion, an enhanced ssFCM framework has been proposed, and has been demonstrated to have highly significant improved accuracy on the NTBC dataset.

Medical technology is a field of work with connection to prevention, diagnosis, monitoring, treatment and care. The company Human care is a well-established company in Sweden with red rollators seen all over Sweden. The product family of Human care has four different units of mobility aid solutions. These are lifting devices, rollators, healthcare beds, and convertible chairs. In common they share the same brand, but they do not have any clear connection to each other when it comes to form, colour and texture. In this thesis a visual brand language is developed and created for the company. At the same time, it is implemented and developed on a lifting solution for patient mobility in the healthcare. To find a brand language which should be easier to implement on the products investigations into the brand and products has been done. By trying to find a common ground in the current products the step from creation to implementation of a guideline will be smaller. Further, research has been done in colour psychology, ergonomics, surface textures and forms. The result of this thesis is a guideline which the company can use as a base when developing new products. In this thesis, it has been implemented on a lifting device for patient transportation.

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Title: The issue of unplanned stoppages caused by failure in medical technology equipment – A study within the hospital of Kalmar with a focus on manage-ment, security and quality Author: Anna Förster, Ambika Linder, Sandra Nyqvist Tutor: Thomas Karlsson Institution: Linnaeus School of Business and Economics - Linnaeus University Kalmar Date: 2011-01-14 Purpose: The purpose of this study was to examine unplanned stoppages caused by medical technology equipment failure in the healthcare operation within the hospital of Kalmar. Our study is based on a number of specifically selected incidents which show the consequences these disruptions cause in management, security and quality within the operation. Our intention was also to examine what role the medical technology department of the hospital plays in the care production operation during these unplanned stoppages. Method: Through a qualitative study we have generated material from a number of interviews with staff working in the hospital of Kalmar. These interviews have given us a deeper perspective of a number of cases that we have chosen to study more closely and which relate to unavailable medical technology equipment. The interviewed respondents have contributed with their knowledge about the current incidents. From a hermeneutical interpretive perspective we have based on knowledge received about the subject, connected the collected empirics with our theoretical frame of reference. Conclusion: We see that management is affected negatively in situations where medical technology equipment has been unavailable, because of an ineffective use of resources in terms of rooms, equipment and personnel. In the cases studied we consider patient security to be relatively good. Nevertheless, the quality within the hospital of Kalmar is affected negatively during these unplanned stoppages, due to service dissatisfaction among some of the patients. Finally we conclude that care staff show a good level of confidence in the medical technology department as a support function and that their availability is highly appreciated. Keywords: Medical technology equipment, unplanned stoppage, maintenance, management, security, quality

<p>A prototype of a haptic and virtual reality simulator has been developed for simulation of the bone milling and material removal process occurring in several operations, e.g. temporal bone surgery or dental milling. The milling phase of an operation is difficult, safety critical and very time consuming. Reduction of operation time by only a few percent would in the long run save society large expenses. In order to reduce operation time and to provide surgeons with an invaluable practicing environment, this licentiate thesis discusses the introduction of a simulator system to be used in both surgeon curriculum and in close connection to the actual operations.</p><p>The virtual reality and haptic feedback topics still constitute a young and unexplored area. It has only been active for about 10-15 years for medical applications. High risk training on real patients and the change from open surgery to endoscopic procedures have enforced the introduction of haptic and virtual reality simulators for training of surgeons. Increased computer power and the similarity to the successful aviation simulators also motivate to start using simulators for training of surgical skills.</p><p>The research focus has been twofold: 1) To develop a well working VR-system for realistic graphical representation of the skull itself including the changes resulting from milling, and 2) to find an efficient algorithm for haptic feedback to mimic the milling procedure using the volumetric Computer Tomography (CT) data of the skull. The developed haptic algorithm has been verified and tested in the simulator. The visualization of the milling process is rendered at a graphical frame rate of 30 Hz and the haptic rendering loop is updated at 1000 Hz. Test results show that the real-time demands are fulfilled. The visual and haptic implementations have been the two major steps to reach the over all goal with this research project.</p><p>A survey study is also included where the use of VR and haptic simulators in the surgical curriculum is investigated. The study starts with a historical perspective of the VR and haptic topics and is built up by answering different questions related to this topic and the implementation of simulators at the medical centres. The questions are of general concern for those developing surgical VR and haptic simulators.</p><p>Suggested future work includes modelling, development and validation of the haptic forces occurring in the milling process and, based on this, implementation in the simulator system. Also, further development of the simulator should be done in close cooperation with surgeons in order to get appropriate feedback for further improvements of the functionality and performance of the simulator.</p>

Thesis (D.Tech.: Clinical Technology)-Durban Institute of Technology, 2005 xxiv, 235 leaves ; ill. ; 30 cm / Fumonisin B1 (FB1) and ochratoxin A (OTA) represent examples of mycotoxins of greatest public health and agro-economic significance. They ex¬ert adverse effects on humans, animals and crops that result in illnesses and economic losses. Fumonisin B1 are cancer-promoting metabo¬lites of Fusarium proliferatum and F verticillioides, (formerly moniliforme), and are implicated in oesophageal cancer. Ochratoxins are metabolites of both Aspergillus and Penicillium species. These compounds are known for their nephrotoxic effects in all animal species and may promote tumours in humans. In man OTA exhibits unusual toxicokinetics, with a half-life in blood of 840 h (35 days) after oral ingestion. Although much is known regarding the toxicology of these toxins, little is known of the effects of these toxins on the immune system. The aim of this study was to determine and compare the immunomodulating effects of FB1 and OTA in human carcinoma. Initial experiments involved isolating lymphocytes and neutrophils from healthy volunteers. The isolated cells were exposed to either FB1 or OTA on a dose and time dependent level and LD50 of the toxins was determined. Thereafter, challenge tests were performed, whereby lymphocytes and neutrophils isolated from volunteers, oesophageal cancer patients and breast cancer patients were exposed to the LD50 dose of either FB1 or OTA for the appropriate time. The effect of the toxins was demonstrated by viability studies, light microscopy and electron microscopy. Cytokine receptors (CK, TNF and CSF) were evaluated by immuno-cytochemical methods and the levels of circulating cytokines (IL –1, IL-6, IL-8, IL-10 and TNF-) were determined using ELISA kits.

In this thesis, I examine the use of medical technology as the product of, among other things, value systems and individual and collective needs; technological use therefore is shown to be culturally influenced and subject to change according to historical and social context. / I describe and discuss the use of the Electronic Fetal Heart Rate Monitor (EFM)--a state of the art form of electronic information technology--in obstetrical care in a rural Canadian hospital and community. The central issue I examine is why this technology was obtained and repeatedly used despite local medical opinion and scientific evidence that it was ineffective as a tool to improve obstetrical outcome, and also had been shown to put pregnant women at considerable risk of unnecessary and potentially harmful interventions during birth. / I describe how EFM use appeared contradictory because medical understanding of EFM use was limited to what I define as "case centered" research; research limited to measuring the impact of the EFM on individual patient outcome. Case centered studies were not examinations either of the EFM itself, or of its associated technical regimens. Moreover, case centered studies were not used to relate the EFM to women's experiences during birth, hospital traditions, or community expectations. These latter relationships, which are ignored in case studies, form the focus of this research and explain why an EFM was used in this community.

Currently, the transplantation of islets of Langerhans is a viable means to maintain control of blood sugar levels and reduce the risk of hypoglycemia in defined populations with brittle type I diabetes mellitus or those requiring pancreatectomy. However, the process of islet isolation is highly variable and not all isolations result in islet numbers or quality suitable for transplantation. This thesis aimed to improve transplantation success through optimization and standardization of the isolation process and to identify pretransplant variables associated with early islet engraftment. A previously disregarded enzyme activity, tryptic-like activity (TLA), has been identified to influence pancreas digestion efficiency and islet isolation success in both the preclinical and clinical situations. For human pancreases, islet isolation success rates improved from 0% in the lowest TLA group to over 50% in the highest TLA groups without affecting islet quality. These findings should help standardize evaluation of enzymes for clinical islet isolation. A closed, automated, pump-made gradient system was compared to the open, manual method for islet separation. No differences were observed in expected gradient volumes, islet yields or total purities between the two methods. The pump-made gradient system successfully removed manual influences on density gradient production while fulfilling regulatory requirements for closed system processing. Islet quantification was evaluated with computer-assisted digital imaging analysis (DIA) and a semi-closed assessment system. By using the DIA system method, which measures islet purity and pellet volume instead of manual counting methods, variation in islet counts and purity reduced by almost half. By using a transplant outcome measurement of C-peptide adjusted by blood glucose and creatinine, we identified four pretransplant factors that affect early transplant outcome. Of the four factors, one was related to the organ transport time, one to function of the islets, and two to the transplanted tissue volume. When these four factors were put into a predictive model, it accounted for about 40% of the transplant outcome. The work contained in this thesis identifies and optimizes a number of critical elements related to islet isolation and transplantation protocols.