Researchers have been trying to find smart health solutions that will allow people to continuously monitor their health through applications connected to the internet. One possible solution involve using nano-machines to create body-centric networks. However, the biggest challenge using nano-machines are how they would communicate with the outside world. To investigate this, I have in this thesis developed a multi-layer channel model for human skin tissues and investigated how signals at the terahertz frequency band interact with skin biomaterial. The model is built upon analytical equations describing electromagnetic propagation in a dielectric medium were the electromagnetic properties of human tissue were collected from different sources. The model were implemented in a flexible matlab program able to simulate different numbers of layers from a library with either fixed or random depths. The human skin model used to gather results were chosen to consist of 4 layers of epidermis, dermis, blood and hypodermis, and the depth of the layers were chosen to vary between typical values for the human body. This Matlab based multi-layer channel model was validated by a similar model made in CST Studio Suite, both for a single layer as well as for a 2-layer scenario. Results from the Matlab program showed that the path loss is significantly affected by frequency and material. The expected path loss could therefore vary significantly, however for a human skin model with depths of 1.23, 3.76, 0.21 and 1.38 mm respectively, the path loss was approximately between 250-350 dB for frequencies of 0.5-1.5 THz at the end distance. Finally, numerical analysis were used on 10 data sets created from the multi-layer channel model in order to develop a simple interpolation equation able to describe path loss through the human skin with varying tissue layer depths. The equation had an average mean error of 4.08 \% and a maximum mean error of 6.61\% against 90 different random data sets.

During proton therapy both target volumes and healthy tissue, including organs at risk (OARs), receives radiation dose. Thus, radiotherapy is a trade-off between good target coverage and OAR sparing. For protons, most of the dose is deposited right before it is stopped, a phenomenon termed the Bragg peak. Beyond this point no dose will be deposited, which is an advantageous feature since it enables more OAR sparing. However, this feature also makes proton therapy sensitive to variations in patient position, uncertainties in dose calculation and geometry/anatomy changes. Geometrical margins are therefore added around the target volume to ensure proper coverage.  An evaluation of the margins and plan robustness for proton therapy of unilateral tonsil cancer was conducted in this study, where the endpoint was to further optimize the margins to account for the trade-off between target coverage and doses to OAR. Verification CTs were compared with the plan CT of seven patients using the software Elastix and MICE toolkit. Dose volume histograms (DVHs) were evaluated together with Hausdorff distances (HdD), target coverage and dose differences along the craniocaudal direction, and related to the patient vertebrae.  Tendencies for the need of larger margins caudally of the cervical vertebra C3 was concluded from the HdD and two patients were selected for replanning. Four new treatment plans were created for each patient in the treatment planning system Eclipse and the resulting proton dose distributions were evaluated in MICE toolkit. Two plans utilized a uniform uncertainty of 4 and 5 mm respectively, and two plans utilized a varying uncertainty around the CTV.  Since Eclipse only allows the user to evaluate and optimize a plan with uniform setup uncertainty, new structures for the CTV had to be created for the varying uncertainty before the optimization. Caudally of C3 added PTV margins of 2 and 3 mm were created. Thereafter these new structures were evaluated and optimized with a setup uncertainty of 3 mm.  The limited available data suggests that the treatment plans with varying margins shows favorable characteristics and may improve the treatment quality. Tendencies for improved balance between target coverage and OAR sparing could be seen for the plan with a PTV margin of 3 mm caudally of C3 and a setup uncertainty of 3 mm. However, more patients need to be included in the study before certain conclusions can be made.

The margins in elite swimming are minimal. One hundredth of a second can be the difference between success and failure. To get the margins on your side, science and technical innovations are playing an increasingly important role in elite sport. Lactate measurement is a tool that is used to measure the lactate threshold, also known as the lactic acid threshold. The lactic acid threshold is then used to plan your workouts and to become aware of your limits. The project group have done market research that has shown that lactate measurements are rarely done in elite swimming because it´s time consuming and expensive. Lactate measurement in swimming is done by taking a blood sample in the ear and by analyzing the blood with a lactate measuring device. The process requires expensive disposable materials and takes between 10-60 seconds each time. This makes it impossible for a swim coach to make measurements on more than two swimmers at a time. The purpose of the project has been to simplify this process. The goal of the project has been to collect measurement data for muscle activity and lactate through experimental studies and analyzes with EMG sensors. Data that can be used for future algorithm development. The goal has also been to develop prototypes for both the product and for an application, this will be a starting point for the development of the final product. The result, Lactatel, is a concept that measures the lactate level of a swimmer in real time in order to optimize training. The concept consists of two sensors that are placed on the back and measure muscle activity. It also consists of an application where the values are displayed. Lactatel is a cheaper alternative in the long run compared to current products and is easier to use for both swimmers and swim coaches. Lactatel does not require any handling of blood and displays lactate values in real time just like a heart rate monitor shows your pulse. The product is capable of measuring lactate on an unlimited number of swimmers simultaneously. Lactatel is a future tool for elite swimmers and will help them reach their full potential and get the margins on their side. / Marginalerna i simning på elitnivå är minimala. En hundradel kan vara skillnaden mellan vinst och förlust. För att få hundradelarna på sin sida används vetenskap och tekniska hjälpmedel allt mer inom elitidrott. Laktatmätning är ett exempel på ett sådant hjälpmedel. Det används för att mäta laktattröskeln, även kallad mjölksyratröskeln. Mjölksyratröskeln används sedan för att planera träning och för att bli medveten om sina begränsningar. Projektgruppen har gjort marknadsundersökningar som visat att laktatmätningar sällan görs inom elitsimning på grund av att det är tidskrävande, dyrt och omständligt. Laktatmätning i simning går till genom att ett blodprov tas i örat och att blodet sedan analyseras i en laktatmätare. Processen kräver dyra engångsmaterial och tar mellan 10–60 sekunder vilket medför att en simtränare inte kan göra mätningar på mer än två simmare i taget. Syftet med projektet har varit att underlätta denna process. Målet med projektet har varit att genom experimentella undersökningar och analyser med EMG-sensorer ta fram mätdata för muskelaktivering och laktat som kan användas för framtida algoritmutveckling. Målet har även varit att utveckla prototyper på både en produkt och tillhörande applikation som ska vara en startpunkt för framtagning av den slutgiltiga produkten. Resultatet, Lactatel, är ett koncept som mäter laktatvärdet hos en simmare i realtid för att kunna optimera och skräddarsy personlig träning. Konceptet består av två sensorer som placeras på ryggen och mäter muskelaktivitet samt en applikation där värdena visas. Lactatel är ett billigare alternativ i längden än nuvarande produkter och är enklare att använda för både simmare och simtränare. Lactatel kräver ingen blodhantering och visar laktatvärdet i realtid likt en pulsklocka visar puls. Produkten klarar av att mäta laktatvärdet på ett obegränsat antal simmare samtidigt. Lactatel är framtidens hjälpmedel för elitsimmare och hjälper dem att nå sin fulla potential och få marginalerna på sin sida.

This is a master thesis project written at the School of Technology and Health within KTH, Flemingsberg. It consisted of making improvements in an existing application for tablets used for training HRV biofeedback that was developed as part of an earlier master thesis within the same school. The software involves the user in paced breathing according to an established method. The method with HRV biofeedback visualises and trains HRV while the user performs paced breathing. This means that the user maximises the variations of time between heart beats which may have potential to reduce stress and sustain health. To improve the software developed earlier at KTH a new graphical user interface was implemented in form of a simple game. In addition further aspects of the program were improved. Furthermore, this thesis tried to find evidence for the optimal frequency and duration of HRV biofeedback training for healthy individuals. For this purpose a literature review was performed, showing a lack of evidence for the effectiveness of HRV biofeedback training in healthy individuals. Therefore a study protocol was developed that can be used in future studies aimed at finding the optimal dosage of HRV biofeedback. / Det här är en rapport från ett examensarbete på masternivå utfört på KTH, Skolan för teknik och hälsa i Flemingsberg. Arbetet handlar om att vidareutveckla en mobil applikation för surfplattor som utvecklats i ett tidigare masterprojekt. Programmet engagerar användaren i andning efter en specifik metod. Metoden med HRV biofeedback bygger på att visualisera och träna upp HRV medan man andas. Detta innebär att maximera de varierande tidsintervallen mellan hjärtats slag vilket har potential att fungera som en behandlingsmetod för att reducera stress och bibehålla god hälsa. Genom att programmera i Java och implementera en ny spelvy i det existerande programmet har applikationen förbättrats. Även andra aspekter av programmet har förbättrats. Arbetet har också inneburit att hitta svar på frågor om optimal dosering och frekvens för träning med HRV biofeedback för att detta ska kunna ge långsiktiga effekter på HRV. En litteraturstudie utfördes för att finna svar på dessa frågor. Det saknas dock studier som påvisar positiva långvariga effekter på hjärtats variabilitet hos friska personer. Därför har ett testprotokoll föreslagits vilket kan vara en grund för att i framtiden göra en studie för att vidare utforska dessa frågor.

Aim: The primary aim of this study was to investigate BICOM Optima with the treatment concept Bicom-Prevent and explore if it can affect physical aspects and wellbeing for participants in this study.   Method:  The study had four participants aged between 25 to 35 years. The study had two test sessions that were accomplished at the University Hospital in Uppsala. First, the study began with a test session, then a treatment period of five weeks with BICOM bioresonance was conducted in the participants' home. The study was finalized with another test session. To get background data of the participants, they all completed different questionnaires about activities, stress and sleeping habits at the first test opportunity. The same form was answered again at the final test opportunity, after the treatment with BICOM Optima. BICOM is a Class 2 medical device based on bioresonance technology.    Results: All of the participants reduced their blood pressure between the two test occasions, and three participants decreased their maximal oxygen uptake capacity. One of the participants suffered an injury during the second test occasion and was not able to finish the test. A second participant was sick when the second test session was, and therefore could not perform the test. As the number of participants was low, the result is greatly affected by the injuries and diseases that existed among the participants during the study. Due to this, no clear correlation between treatment with BICOM bioresonance and an increase in maximal oxygen uptake could be seen.   The results from the stress impact of the participants at the first and the second test session are very similar. No major difference could be identified, and therefore it is difficult to determine whether BICOM had any effects according to this during the treatment period of five weeks. What could be seen was that all participants received a lower blood pressure at the final test.    Conclusion: The conclusion made during the study was that to be able to demonstrate whether BICOM bioresonance have an impact on physical aspects and well-being for the participants a longer treatment period and more comprehensive studies is required.   Key Words: Bicom Optima, Heart rate variability, sleep, stress, case study, bioresonance.

Cancer is a tough disease and in some cases is difficult to treat, which leads to too many people dying. Of the cancer diagnoses made each year, 3.2 million of these are primary and secondary liver cancer. The world needs to be able to reduce these tragic outcomes and to be able to remove a liver tumor in a more patient-centered way. Today, resection of the liver is performed through an open operation, which entails a long and more painful recovery process for the patient compared to a keyhole surgery. The reason keyhole surgery is not used in these operations today is because the surgeon lacks sufficient visualization, which makes it difficult to navigate and remove the tumor with high precision.  Navari Surgical AB is therefore developing a solution that makes it possible to apply keyhole operations for liver cancer by increasing the visualization with Augmented Reality. For the technology to work, a single-use device must be attached to the liver surface and it then acts as a navigation marker in their overall solution. The mission has been to examine and develop a fastener for the single-use device that attaches to the liver and can be removed without damaging the surface. The fastener must also be able to maintain the same position throughout the operation, withstand the moist environment inside the abdomen and comply with the Medical Device Regulations. After research and several tests, the project was able to result in a working fastener, which is a specific hydrogel. Due to the fact that the hydrogel does not adhere to plastic, it will be attached to the single-use device with medical epoxy and a layer of carbon fiber film. Together, these components make up a complete and functioning product, called Navmark. Applying keyhole surgery for liver cancer with Navmark and Navari's technology has several advantages. First, together they increase the surgeon's visualization and localization of the tumor, which in turn increases the precision of the operation. Undergoing keyhole surgery, instead of open surgery, also results in fewer complications and shorter recovery time for the patient. By applying Navmark and Navari's technology, it will in the future be possible to carry out keyhole surgery for liver cancer in a minimally invasive and more patient-centered way, which in turn will be able to save lives.

Introduction Alarms have always been an agent of notification, but it can also be distressing and annoying. As much as the sounds of alarm effects the patient’s care and their well-being, it also impacts on the well-being of the healthcare workers which often goes unnoticed as the priority is on the patient-care. Purpose The purpose of the thesis was to investigate the problems of the alarms fatigue and how the improvisations can be done technically and in the point of management and technical organization. Methods The study was conducted through interviews to healthcare staffs and the management of the departments. Four participants from two different hospitals participated in the interview session. Result and Analysis The results obtained from the interviews are analysed with the literature reviews that have been studied and the outcome from the interview tallies on the findings from the literature studies. Additional measures have been implemented based on observation and feedback among the healthcare workers. Conclusion The interview feedback supports the studies of the literature reviews and the measures that have been practiced and implemented to improve the workflow and fatigue issues based on the feedback of the hospital interviews have shown improvements in some departments. The outcome can be presented as a suggestion on future improvements, with better access to newer technology on making working efficiency better. / Introduktion Alarm används i varnande syfte, men kan upplevas som irriterande och störande. Så mycket som det kan upplevas som störande för patienterna, så är det personalens välbefinnande som avgör hur alarmen hanteras eller om de passeras obemärkt. Syfte Syftet med detta projekt är att undersöka problematiken med alarmutmattning och hur detta hanteras tekniskt utifrån personal- och ledningsnivå. Metod Studien genomfördes genom intervjuer med vårdpersonal och förvaltningen av avdelningarna. Fyra deltagare från två olika sjukhus deltog i intervjusessionen. Resultat och Analys  Resultaten som erhållits från intervjuerna analyseras med litteraturöversikter som har studerats och resultatet från intervjun berättar om resultaten från litteraturstudierna. Ytterligare åtgärder har genomförts baserat på observationer och feedback hos sjukvårdsarbetarna. Slutsats Intervjuåterkopplingen stöder studierna av litteraturgranskningarna och de åtgärder som har praktiserats och genomförts för att förbättra arbetsflödet och trötthetsfrågorna baserade på feedback från sjukhusintervjuerna har visat förbättringar i vissa avdelningar. Resultatet kan presenteras som ett förslag på framtida förbättringar, med bättre tillgång till nyare teknik för att göra arbetseffektiviteten bättre.

The abdominal aorta is the largest blood vessel in the abdomen and the main supplier of blood to the lower body. An abdominal aortic aneurysm (AAA) is an unnatural enlargement of the abdominal aorta, which is a serious condition with a high risk of mortality. If the aneurysm exceeds a certain diameter or growth rate, surgical interventions are justified. Use of a diameter-based criterion has been proven to be inaccurate though since some smaller aneurysms can rupture whilst some larger aneurysms remain quiescent. A biomechanical rupture risk assessment (BRRA) that utilizes the finite element method can be used to evaluate the risk of aneurysm rupture. The BRRA calculates the stresses in the aneurysm based upon CT scans and patients blood pressure. Comparing the stresses with the strength of wall in the aneurysm makes it possible to evaluate the risk of rupture. If the stress exceeds the strength, the aneurysm will rupture. To calculate the strength of the vessel wall, a strength equation is used. The strength equation consists of risk factors such as family history, gender, intra luminal pressure and aneurysm diameter. To individualize the assessment further it would be possible to identify and use other risk factors. Rupture risk factors were searched for through two spate literature searches. To identify the risk factors the search utilized keywords such as “rupture risk factors” and “abdominal aortic aneurysm” together with “peak wall stress” or “wall stress”. The search also used a state of the art article from previous research, which contained a list of risk factors that could be searched for. For a factor to be used in this study they had to be global risk factors. Instead of increasing the risk of rupture in a localised point in the aneurysm, a global factor affects the aneurysm uniformly throughout its entirety. The search focused on statistical trials that evaluate the factors impact on wall stress or wall strength. An AAA wall strength equation was constructed based on the rupture risk factors that were identified. This equation was translated into the Finite element analysis program (FEAP) to evaluate its behaviour. A statistical analysis was performed in Matlab using data from the program A4CLINICS developed by VASCOPS gMBh. Using 41 patients along with known patient characteristics and CT scans Biomechanical rupture risk assessment (BRRA) was conducted using the new strength equation. The assessment resulted in a new peak wall rupture index (PWRI). The resulting data was separated into two groups based upon their volume growth rate, one fast growing and one slow growing group. This separation was done for both the VASCOPS strength equation and the new one. Pearson correlation testing was used to test the correlation between both strength equations and volume growth or diameter growth. To evaluate the sensitivity of the strength equation, receiver operating characteristics (ROC) curves were also used. The PWRI in fast and slow groups were not different (p-values of 0.1257 for VASCOPS and 0.0679 for the new equation). The Pearson correlation coefficients showed a higher correlation between new PWRI and volume growth compared to diameter growth. The new PWRI had a higher sensitivity for predicting the volume growth compared to the diameter growth. Initial volume and diameter had the highest sensitivity of all predictors. The new PWRI could be used to predict volume growth. Volume growth is a potential predictor of aneurysm rupture, which indicates the new PWRI can be used in the BRRA. But to achieve results with statistical significance, new simulations using larger population must be performed and the strength equation must be revised.

In radiotherapy the main goal is to kill cancer cells, prevent them from growing and reproducing, while healthy tissue is spared. One technique to treat cancer is to use external radiotherapy where a linear accelerator (linac) is used to generate a high energy radiation photon beam. An MRI-linac is a combined magnetic resonance imaging (MRI) and linac and is used to perform adaptive radiotherapy. However, in order to perform treatments on the MRI-linac commissioning measurements must be performed to acquire all radiation beam data, verify its accuracy, and enter all these data into a com- puterized treatment planning system (TPS). To acquire the radiation beam data absorbed dose, output factors, percentage depth dose (PDD) curves and cross- and inplane profiles are measured. This was done together with a gamma analysis by Elekta in connection with the installation of the Elekta Unity MRI-linac at the Uppsala University Hospital in the year 2019. In this project these commissioning measurements and gamma analysis have been recreated and compared with the expected dose distributions calculated in the TPS Monaco. In addition to this a comparison with the result from Elekta has been done. With a water phantom, PTW BEAMSCAN MR, and three different detectors, PTW Semiflex 3D, PTW microDiamond and Farmer chamber PTW30013, PDDs and profiles have been acquired at different field sizes at gantry angles 0° and 270°. The absorbed dose was measured under reference conditions, depth 10 cm and field size 10x10 cm2, to be 0.8656 cGy/MU and 1.1666 cGy/MU at gantry angle 0° and 270°, respectively. This yielded a difference between Elekta’s result of 0.02% and -0.24% for 0° and 270°, respectively. The output factors were measured at 0° and 270° and differed with Elekta’s result in a range from -2.45% to 0.04%. From these values the PDDs and profiles were created and compared with the calculated result from Monaco.

Diagnosing abnormal fetal cardiac function using ultrasound is a complicated procedure which makes it difficult to obtain high quality results from ultrasound examinations that are performed shortly before delivery. Color tissue Doppler imaging (cTDI) is the echocardiographic technique that has been used to obtain the data for this project. Subtle changes in the fetal cardiac function caused by a variety of complications can possibly be detected using cTDI. Fetuses suffering from these complications are often involved in high-risk deliveries. Combining the data obtained from cTDI with Artificial Intelligence (AI) may improve precision and accuracy when it comes to diagnosing pathological conditions involving fetal cardiac function before delivery. AI uses machines to perform and execute tasks that are characteristic of human intelligence. AI can be achieved by using deep learning. Deep learning uses algorithms called artificial neural networks that are inspired by the biological structure and function of the human brain. The neural networks classify information in a similar manner to the human brain. A platform that uses deep learning can make statements or predictions based on the data fed to it. The AI platform Peltarion uses deep learning to perform tasks. The aim of this project was to use Peltarion to evaluate the possibility of predicting high-risk deliveries with abnormal perinatal outcome by using data obtained by cTDI velocity recordings of the fetal heart. The data included myocardial velocity recordings from 107 pregnancies, out of the 107 pregnancies 82 of the babies were born healthy while 25 babies had an adverse perinatal outcome. The data was uploaded in the platform and three models were built and trained in order to evaluate the performance of the platform using the data. The parameters that have been used to determine the results are loss, accuracy and precision. The results showed that the accuracy parameter was measured to be 0.8 in all cases which means that the model correctly predicts if a fetal heart is healthy or likely to have an adverse outcome 80% of the time. The precision parameter was measured to be around 0.4 which means out of all the times the model predicted a fetal heart to have an adverse outcome, only 40% truly had an adverse outcome. It was concluded that a substantially larger amount of evenly distributed data is required to appropriately evaluate the possibility of using fetal myocardial velocity recordings as data for the AI platform Peltarion to predict high-risk deliveries.