<p>This study is aimed to determine the electromyographic signals of the forearm, using Ag/AgCl electrodes. The four major muscles of forearm, which are providing the bioelectrical currents, have been displayed and analysed to determine the different activities. In order to record the signals, an EMG device has been developed and installed and a schematic has also been presented in this paper.</p>

<p>Arbetets syfte var att utreda reliabilitet och validitet för en blickregistreringsutrustning, JAZZ™, som finns på FOI i Linköping. Dessutom skulle utredningen klargöra huruvida utrustningen kan användas till att detektera mental arbetsbelastning. Tre olika studier gjordes på 17 försökspersoner. Endast sackader i horisontalled studerades, trots att utrustningen har ett flertal andra mätområden. Första studien utredde utrustningens reliabilitet och validitet, om JAZZ™ mätte det som avsågs (i det här fallet sackader i horisontalled) samt om mätningarna var konsekventa från ett försökstillfälle till ett annat. Den andra och tredje studien behandlade mental arbetsbelastning. Även subjektiva bedömningar togs med i utredningen då försökspersonerna fick svara på en enkät efter varje genomfört försök. Statistiska resultat visade bland annat signifikanta skillnader mellan de olika studierna och inga signifikanta skillnader mellan de inbördes försöken, vilket indikerar att JAZZ™-utrustningen är reliabel och valid. Tillsammans med de subjektiva bedömningarna kan det också påvisas att utrustningen kan detektera mental arbetsbelastning.</p>

Datorn är ett viktigt verktyg i vår vardag. För rörelsehindrade kan datorn vara en förutsättning för att kunna fungera i vardagen. Datorn har som tekniskt hjälpmedel gett funktionshindrade större möjligheter till meningsfulla aktiviteter, såsom att på egen hand skriva, läsa och kommunicera. Samtidigt är det inte alltid funktionshindrade klarar av att använda vanliga datorer utan behöver alternativa inmatnings- och styrenheter. Målet med denna licentiatavhandling har varit att utveckla tekniker som ska stödja personer med rörelsebegränsningar. Främst har arbetet varit att utveckla alternativa tekniker för att kunna manövrera en dator. Viktiga aspekter i arbetet har varit att göra hjälpmedlen användarvänliga, möjliga att individanpassa, och att ta tillvara de tänkta användarnas synpunkter kring behov och önskemål. Vidare har inmatningsenheten utvärderats av användare och även tillämpats som ett rehabiliteringsverktyg för en mindre patientgrupp med nackskador, så kallade pisksnärtskador. Utöver dessa vetenskapliga mål har produktionsaspekterna varit viktiga. För att säkerställa att enheten ska kunna bli en produkt måste den kunna produceras och säljas till ett rimligt pris och detta måste beaktas under hela utvecklingsprocessen. En alternativ datormus baserad på MEMS-gyroskop har utvecklats. Utvecklingen är gjord utifrån de krav de tilltänka användarna ställde på den alternativa datormusen och enheten är utprovad och förbättrad i en iterativ process mellan utvecklare och användare, så kallad användarcentrerad utvecklingsprocess. MEMS-gyron var den typ av rörelsesensor som bäst svarade mot de krav som ställdes på enheten. De användare som deltog vid ett längre fältprov var samtliga nöjda och ville behålla musen. För att underlätta processen att välja rätt typ av gyro och att kunna utvärdera deras stabilitet under olika omgivningsfaktorer, såsom temperatur och vibrationer, har en testrig för gyron utvecklats. Människors rörelsemönster skiljer sig från industriella tillämpningar och därför behövs en speciell testrigg. Testriggen roterar gyron och mäter sensorsignalen under olika betingelser. Flera gyron kan testas samtidigt och testdatat kan sparas och analyseras i efterhand. Ett interaktivt datorbaserat träningsprogram har utvecklats och utvärderats vid en pilotstudie tillsammans med den alternativa datormusen. Syftet var att låta nackskadade utföra huvudrörelser och få en feedback på att de tränar rätt. Resultatet pekar på att detta kan vara en lovande metod. / Computers are important tools. People with motion disabilities sometimes are dependent on a computer and used as a technical aid the computer has improved the possibilities to perform meaningfull tasks, as writing, reading and communicating. However, disabled often need an alternative input device to control a computer.   The aim with this licentiate theses has been to develope techniques to support persons with motion limitations. Focus has been to develope alternative techniqes to control a computer. Important aspects have been user-friendlieness, possiblilities to perform individual adaptions and incorporatation of specifications from the intended users. Further, the input device has been evaluated by users and applied as a rehabilitation tool for a smaller patient group of persons with whiplash associated disorders.   Further, production aspects are important. To make the unit into a product, it has to be possible to produce and sell to a reasonable price. This has to be considered during the whole development process.   An alternative computer mouse based on a MEMS gyroscope has been developed. The specifications made by the users has been used as a starting point in the development and the unit has been evaluated and improved in an iterative process, so called user centric development. MEMS-gyros were the type of motion sensors most corresponding to the demands. The users that participated in a longer field test were all satisfied and wanted to keep the mouse.   To improve the process to choose right kind of gyro and to be able to evaluate their stability depending on factors as temperature and vibration, a test-rigg for gyros has been developed. Human motion pattern differs from industrial applications and therefor a special test-rigg was needed. The testrigg rotates the gyros and measures the sensor signal. Several gyros can be tested simultaneously and data can be stored and analysed afterwards.   An interactive computerbased training program has been developed and evaluated in a pilot study together with the altrenative computer mouse. The aim has been to let people with neck injuries perform head motions and get feedback that they perform the right kind of training. The result is promising.

Arbetets syfte var att utreda reliabilitet och validitet för en blickregistreringsutrustning, JAZZ™, som finns på FOI i Linköping. Dessutom skulle utredningen klargöra huruvida utrustningen kan användas till att detektera mental arbetsbelastning. Tre olika studier gjordes på 17 försökspersoner. Endast sackader i horisontalled studerades, trots att utrustningen har ett flertal andra mätområden. Första studien utredde utrustningens reliabilitet och validitet, om JAZZ™ mätte det som avsågs (i det här fallet sackader i horisontalled) samt om mätningarna var konsekventa från ett försökstillfälle till ett annat. Den andra och tredje studien behandlade mental arbetsbelastning. Även subjektiva bedömningar togs med i utredningen då försökspersonerna fick svara på en enkät efter varje genomfört försök. Statistiska resultat visade bland annat signifikanta skillnader mellan de olika studierna och inga signifikanta skillnader mellan de inbördes försöken, vilket indikerar att JAZZ™-utrustningen är reliabel och valid. Tillsammans med de subjektiva bedömningarna kan det också påvisas att utrustningen kan detektera mental arbetsbelastning.

This study is aimed to determine the electromyographic signals of the forearm, using Ag/AgCl electrodes. The four major muscles of forearm, which are providing the bioelectrical currents, have been displayed and analysed to determine the different activities. In order to record the signals, an EMG device has been developed and installed and a schematic has also been presented in this paper.

The presence of hypoxia in tumors has been related to poor prognosis and low overall survival. In particular, cyclic hypoxia has been related to higher metastatic potential. Hence, it is important to study the mechanisms involved in the response of tumors when these experience cyclic hypoxia. In this work A-07-GFP human melanoma xenografts with dorsal window chambers were used as a model to study the effects of exposure to cyclic hypoxia on tumor growth and on the morphology and function of the tumor vascular networks. First-pass imaging of a fluorescent tracer was used to study the function of tumor vasculature, and tumor vascular morphology was assessed by producing vascular masks from high-resolution images. Vascular morphology was described by quantification of vascular length density, vascular area fraction, interstitial distance and vessel diameter. The function of the tumor vasculature was assessed by quantification of the blood supply times (BSTs). It was found that exposure to cyclic hypoxia resulted in higher vascular densities, a trend towards higher BST values and decreased growth rate in the tumors. The results could be associated with enhanced angiogenesis in the tumors that received the cyclic hypoxia treatment due to overexpression of pro-angiogenic genes regulated by HIF-1&#945;.

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A survey was conducted to answer two basic questions: 1) What are the medical bacteriology laboratories of Indiana using as criteria for identifying microorganisms? and 2) What is the basis for these criteria? The author developed a questionnaire used as the survey instrument. One hundred fifty questionnaires were mailed to medical laboratories throughout Indiana. Sixty percent of the laboratories responded. This study lists all responses and gives a description and/or evaluation of each procedure.In addition, the researcher discusses some of the factors influencing the type of procedures that are being used. Data collected by this research will be submitted to the biology department at Ball State University to help establish more concrete guidelines that can be used to update course content.

Patients with idiopathic normal pressure hydrocephalus (INPH) have a disturbance in the cerebrospinal fluid (CSF) system. The treatment is neurosurgical – a shunt is placed in the CSF system. The infusion test is used to assess CSF system dynamics and to aid in the selection of patients that will benefit from shunt surgery. The infusion test can be divided into three parts: a mathematical model, an infusion protocol and a parameter estimation method. A non-linear differential equation is used to mathematically describe the CSF system, where two important parameters are the outflow conductance (Cout) and the Pressure Volume Index (PVI). These are used both for clinical and research purposes. The analysis methods for the non-linear CSF system have limited the infusion protocols of presently used infusion investigations. They come with disadvantages such as long investigation time, no estimation of PVI and no measure of the reliability of the estimates. The aim of this dissertation was to develop and evaluate novel methods for infusion protocols, mathematical modelling and parameter estimation methods for assessment of CSF system dynamics. The infusion protocols and parameter estimation methods in current use, constant pressure infusion (CPI), constant infusion and bolus infusion, were investigated. The estimates of Cout were compared, both on an experimental set-up and on 20 INPH patients. The results showed that the bolus method produced a significantly higher Cout than the other methods. The study suggested a method with continuous infusion for estimating Cout and emphasized that standardization of Cout measurement is necessary. The non-linear model of the CSF system was further developed. The ability to model physiological variations that affect the CSF system was incorporated into the model and it was transformed into a linear time-invariant system. This enabled the use of methods developed for identification of such systems. The underlying model for CSF absorption was discussed and the effect of baseline resting pressure (Pr) in the analysis on the estimation of Cout was explored using two different analyses, with and without Pr. A novel infusion protocol with an oscillating pressure pattern was introduced. This protocol was theoretically better suited for the CSF system characteristics. Three new parameter estimation methods were developed. The adaptive observer was developed from the original non-linear model of the CSF system and estimated Cout in real time. The prediction error method (PEM) and the robust simulation error (RSE) method were based on the transformed linear system, and they estimated both Cout and PVI with confidence intervals in real time. Both the oscillating pressure pattern and the reference CPI protocol were performed on an experimental set-up of the CSF system and on 47 hydrocephalus patients. The parameter estimation methods were applied to the data, and the RSE method produced estimates of Cout that were in good agreement with the reference method and allowed for an individualized and considerably reduced investigation time. In summary, current methods have been investigated and a novel approach for assessment of CSF system dynamics has been presented. The Oscillating Pressure Infusion method, which includes a new infusion protocol, a further developed mathematical model and new parameter estimation methods has resulted in an improved way to perform infusion investigations and should be used when assessing CSF system dynamics. The advantages of the new approach are the pressure-regulated infusion protocol, simultaneous estimation of Cout and PVI and estimates of reliability that allow for an individualized investigation time.

In this thesis we examine several extensions to the dynamic linear model framework, outlined by Harrison and Stevens (1976), in order to adapt these models for use in the on-line analysis of medical time series that arise from routine clinical settings. The situation with which we are most concerned is that where we are monitoring individual patients and wish to detect abrupt changes in the patient's condition as soon as possible. A detailed background to the study and application of dynamic linear models is given, and other techniques for time series monitoring are also discussed when appropriate. We present a selection of specific models that we feel may prove to be of practical use in the modelling and monitoring of medical time series, and we illustrate how these models may be utilized in order to distinguish between a variety of alternative changepoint-types. The sensitivity of these models to the specification of prior information is examined in detail. The medical background to the time series examined requires the development of models and techniques enabling us to analyze generally unequally-spaced time series. We test the performance of the resulting models and techniques using simulated data. We then attempt to build a framework for bivariate time series modelling, allowing, once more, for the possibility of unequally spaced data. In particular, we suggest mechanisms whereby causality and feedback may be introduced into such models. Finally, we report on several applications of this methodology to actual medical time series arising in various contexts including kidney and bone-marrow transplantation and foetal heart monitoring.