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  • 1.
    Abdirahman, Khalid
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Förnberg, Sebastian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Styrsystem för solcellsladdade batterier2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of solar cells is continuously increasing in Sweden and the powergenerated by the solar cells is usually stored in lead acid batteries. These batterieshave a bad impact on the environment as much energy and environmentallyhazardous materials like lead and sulfuric acid are required to manufacture thesebatteries. Östersjökompaniet AB and many of its customers realize the importanceof sustainable thinking and were interested in knowing if it was possible tomaximize the lifetime of these batteries. During the course of the work, differentmethods of battery charging and discharging were analyzed that could affect thebatteries lifetime and how to take care of them to optimize them. A chargecontroller was used to optimize the charge of the battery. To calculate theremaining state of charge in the battery, the Extended voltmeter method was used.A prototype that was able to charge the batteries optimally, warn when the batterycapacity became too low, and a user-friendly application for battery monitoring wasdesigned. The calculated lifetime of a battery is not an exact science. According tostudies the lifetime of a battery can be doubled if it is c

  • 2.
    Abraham, Johannes
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Romano, Robin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Automatisk kvalitetssäkring av information för järnvägsanläggningar: Automatic quality assurance of information for railway infrastructure2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    With increased expectations for the expansion of the future railway, this entails an increased load on the current railway network. The result of the expansion can be an increasing number of cancellations and delays. By taking advantage of technological innovations such as digitalization and automation, the existing system and work  processes can be developed for more efficient management.   The Swedish Transport Administration sets requirements for Building Information Modeling (BIM) in procurements. The planning of signal installations within the railway takes place in Sweco using the CAD program Promis.e. From the program, lists containing the information of the objects (BIS-lists) can be retrieved. The  Swedish Transport Administration requires that the attributes must consist of a  certain format or have specific values. In this thesis project, methods for automatic quality assurance of infrastructure information and the implementation of the method for rail projects were examined. The investigated methods include the  calculation program Excel, the query programming language SQL and the process of ETL.  After analyzing the methods, the ETL process was chosen. The result was that a  program was created to automatically select the type of BIS list that would be  reviewed and to verify that the examined attributes contained allowed values. In  order to investigate whether the cost of the programs would benefit the company in addition to the quality assurance, an economic analysis was carried out. According to the calculations, the choice of method could also be justified from an economic  perspective.

  • 3. Abtahi, Farhad
    et al.
    Forsman, Mikael
    Diaz-Olivazrez, Jose A.
    KTH, School of Technology and Health (STH).
    Yang, Liyun
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Lu, Ke
    KTH, School of Technology and Health (STH).
    Eklund, Jörgen
    KTH, School of Technology and Health (STH).
    Lindecrantz, Kaj
    KTH, School of Technology and Health (STH).
    Seoane, Fernando
    Teriö, Heikki
    Mediavilla Martinez, Cesar
    Aso, Santiago
    Tiemann, Christian
    Big Data & Wearable Sensors Ensuring Safety and Health @Work2017In: GLOBAL HEALTH 2017, The Sixth International Conference on Global Health Challenges, 2017Conference paper (Refereed)
    Abstract [en]

    —Work-related injuries and disorders constitute a major burden and cost for employers, society in general and workers in particular. We@Work is a project that aims to develop an integrated solution for promoting and supporting a safe and healthy working life by combining wearable technologies, Big Data analytics, ergonomics, and information and communication technologies. The We@Work solution aims to support the worker and employer to ensure a healthy working life through pervasive monitoring for early warnings, prompt detection of capacity-loss and accurate risk assessments at workplace as well as self-management of a healthy working life. A multiservice platform will allow unobtrusive data collection at workplaces. Big Data analytics will provide real-time information useful to prevent work injuries and support healthy working life

  • 4.
    Ahluwalia, A.
    et al.
    Italy.
    De Maria, C.
    Italy.
    Lantada, A. D.
    Spain.
    Pietro, L. D.
    Italy.
    Ravizza, A.
    Italy.
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Madete, J.
    Kenya.
    Makobore, P. N.
    Uganda.
    Aabloo, A.
    Estonia.
    Kitsing, R.
    Estonia.
    Leivobits, A.
    Estonia.
    Towards open source medical devices current situation, inspiring advances and challenges2018In: BIODEVICES 2018 - 11th International Conference on Biomedical Electronics and Devices, Proceedings; Part of 11th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2018, SciTePress, 2018, p. 141-149Conference paper (Refereed)
    Abstract [en]

    Open Source Medical Devices may be part of the solution towards the democratization of medical technologies pursuing Universal Health Coverage as part of the Sustainable Development Goals for United Nations. Recent technological advances, especially in information and communication technologies, combined with innovative collaborative design methodologies and manufacturing techniques allow for the mass-personalization of biodevices and help to optimize the related development times and costs, while keeping safety in the foreground through the whole life cycle of medical products. These advantages can be further promoted by adequately fostering collaboration, communication, high value information exchange, and sustainable partnerships and by extending the employment of open source strategies. To this end, within the UBORA project, we are developing a framework for training the biomedical engineers of the future in open-source collaborative design strategies and for supporting the sharing of information and the assessment of safety and efficacy in novel biodevices. An essential part of this open-source collaborative framework is the UBORA e-infrastructure, which is presented in this study, together with some initial success cases. Main future challenges, connected with regulatory harmonization, with educational issues and with accessible and open design and manufacturing resources, among others, are also presented and discussed.

  • 5.
    Ahluwalia, Arti
    et al.
    Univ Pisa, Dept Ingn Informaz, Bioengn, Pisa, Italy..
    De Maria, Carmelo
    Univ Pisa, Dept Ingn Informaz, Bioengn, Pisa, Italy..
    Diaz Lantada, Andres
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Madete, June
    Univ Pisa, Res Ctr E Piaggio, Pisa, Italy.;Kenyatta Univ, Nairobi, Kenya..
    Makobore, Philippa Ngaju
    Uganda Ind Res Inst, Instrumentat Div, Kampala, Uganda..
    Ravizza, Alice
    Univ Pisa, Pisa, Italy..
    Di Pietro, Licia
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Munoz-Guijosa, Juan Manuel
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Tanarro, Enrique Chacon
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Torop, Janno
    Tartu Ulikool, Inst Technol, Tartu, Estonia..
    Biomedical Engineering Project Based Learning: Euro-African Design School Focused on Medical Devices2018In: International Journal of Engineering ,Science and Innovative Technology, ISSN 0949-149X, E-ISSN 2277-3754, Vol. 34, no 5, p. 1709-1722Article in journal (Refereed)
    Abstract [en]

    Biomedical engineering (BME) has the potential of transforming medical care towards universal healthcare by means of the democratization of medical technology. To this end, innovative holistic approaches and multidisciplinary teams, built upon the gathering of international talent, should be encouraged within the medical industry. However, these transformations can only be accomplished if BME education also continuously evolves and focuses on the internationalization of students, the promotion of collaborative design strategies and the orientation towards context relevant medical needs. In this study we describe an international teaching-learning experience, the "UBORA (Swahili for 'excellence') Design School". During an intensive week of training and collaboration 39 engineering students lived through the complete development process for creating innovative open-source medical devices following the CDIO ("conceivedesign-implement-operate") approach and using the UBORA e-infrastructure as a co-design platform. Our post-school survey and analyses showed that this integral teaching-learning experience helped to promote professional skills and could nurture the future generation of biomedical engineers, who could transform healthcare technology through collaborative design oriented to open source medical devices.

  • 6.
    Aldahan, Leith
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Kudoori, Ivan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Utvärdering av roterande borstlösfrekvensomformare tillspårledningar2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Track lines are used in subway stations to show the train locations and determine the speed of the train by chopping the frequency. The frequency of the track lines is obtained from a rotary frequency converter. In today's stations, rotary frequency converters with brushes are commonly used. These emit a great deal of heat in some relays and produce environmental problems in the form of carbon dust from the brushes. The existing systems have been used for over 30 years and obtaining spare parts and conducting maintenance on the systems can be difficult.

    This degree project examines the possibility of newer systems being built on a rotating brushless frequency converter, where the spare parts and servicing would be available for at least the next 25 years.

    The project surveys and compares different rotating brushless frequency converters from different suppliers to find an identical frequency converter to meet the requirements of the Traffic Administration.

    The result of this study has had a lot of focus on the problem area with the brushed frequency converter that produces harmful substances such as carbon dust and the heat in the relay room. Discussions with manufacturing companies of rotating brushless frequency converters have been made during this study where possible options were discussed for further development of the system in relay rooms. The result has also discussed the possibilities of using the new system of frequency converters with brushless motor and generator instead of the current brushed frequency converter available in the facility. The result has also shown that the rotating brushless frequency converter can convert the frequency to 75 Hz. The new system meets RAMS requirements of the Trafikförvaltning, and the system lasts for at least 25 years. This was a major requirement of the Trafikförvaltning, which was fulfilled during this study.

  • 7.
    Alfrijat, Christopher
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Eriksson, Rasmus
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Analys och utvärdering av LED-belysning i Stockholms tunnelbana2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Trafikförvaltningen, responsible for public transport in Stockholm, has started a project to replace existing luminaires in the subway of Stockholm to LED lights. This thesis could be a basis for an upcoming procurement.

    In this report, various models of LED lights technical specifications will be evaluated based on the environmental requirements in Stockholm’s subway, where the existing luminaires will be replaced. For this environment, there is no standard regarding LED lights today. With the help of literature studies and tests, a groundwork for a specification could be made. The tests were only made on a selection of LED lights and their technical specifications were presented. All luminaires passed the EMC (electromagnetic compatibility) tests that were made in order to determine any interference with Stockholm’s public transport (SL) radio communication system.

    Environmental aspects and economical aspects of the implementation of LED lights has been taken into consideration.

  • 8.
    Alkhatib, Husam
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Developing an Optimal Design for A Heart Container Operated Via Drone2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In the healthcare system when a patient is waiting for a donated heart, the choice of the transportation method is critical. Thus, the efficiency of this procedure relies on the traveling time, which could affect the ischemic time, which is the time that heart can be discharged outside the human body. For best patient outcome, the heart has to be transplanted within four hours from the donor to the recipient. By transporting the donated heart via Unmanned Aerial Vehicle (UAV, or drone), both the time and the cost required for the heart transportation will be minimized. This thesis intends to explore the specifications needed for the design and manufacture of a heart container and pick-up system for a drone, which will be able to transport a donated heart between hospitals.

  • 9.
    Alsaeede, Mustafa
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Test and Evaluation of a Novel Passive Tool Used For Blood Dilution in Hematology Analyzers2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Executive Summary

    The Complete Blood Count (CBC) is considered one of the most commonly performed screening tests in medical diagnostics. The CBC is performed using a hematological analyzer, which counts the numbers and types of different cells within the blood. However, due to the high concentration of cells in the blood samples to be counted, the dilution process is considered an essential factor for obtaining accurate counting results. Below is an investigation for an invention of a unique method and device for blood sample dilution in hematology analyzers. As mentioned, before starting an analysis a hematology cell counter device must dilute a precise defined volume of a whole blood sample with a diluent reagent (in this study 20ml of a blood sample is diluted with 4,5ml of diluent reagent). This dilution process must be accurate and repeatable with a high precision to produce the target dilution ratio (here 1:200). Exclusive to almost all hematology analyzers today, shear values (SV) are used to obtain highly precise volumes. These SV components are however very costly and add a higher complexity to the systems. This thesis was therefore aimed as an experimental evaluation for a novel passive dilution tool called shearing block (SB), which could possibly then replace the SV and be used in the coming Haematology Analyzer Devices manufactured by Boule Medical AB. The SB has the advantages of being low cost, having a simple mechanism, being much more flexible for integration with any microfluidic system and also eliminates the need for complex control systems or equipment, thereby lowering the need for calibration and maintenance. If a SB could replace the SV with an equally precise accuracy on the 20ml blood volume it would be highly beneficial.

     

    The set hypothesis was that the dilution process via the SB, will only be affected by blood viscosity. Through changing the blood’s viscosity, via changing the hematocrit concentration (HCT) and blood sample temperature, this study aimed to conclude if this gave a significant effect on the blood sample dilution via the SB. This was achieved through two performed experiments both including the same control group (CG) along with a test group (TG). All tests were performed using the same blood sample, the same reference measuring device (Medonic M32) and experimental setup. The experimental setup included the control group, CG, (N=30) consisting of 20µl blood samples aspirated through an electronic pipette in room temperature condition being mixed with 4,5ml of diluent reagent that had been automatically dispensed by the Medonic M32 instrument. The 20µl blood together with the 4,5ml diluent resulted in the targeted 1:200 dilution ratio. The test group, TG, (where N=30 for each respective group) was diluted through the SB through a fully automated process for the targeted 1:200 dilution. All diluted blood samples were then analyzed on the Medonic M32 for all hematology parameters and the hemoglobin (HGB) parameter was used as an indicator to quantify the blood volume in the TG runs as compared to the CG reference runs. Two test groups (TG) were analyzed: the first investigating the effect of the HCT and the second of the sample temperature on the blood volume (before dilution) in the SB. The HCT concentration levels were tested at 15%, 27%, 33% and 58% with samples and test run and kept at a constant 25°C. The second test group investigated the effect of 15°C, 25°C, 35°C and 39°C on a blood sample with a constant HCT of 33%.

    The main aim of this experimental study was to validate the SB simulation. However, the experiments results, showed that the diluted blood volume via SB was strongly influenced by changes in hematocrit concentration and that the unwanted additional blood volume, was increasing directly proportionally with hematocrit concentration.  On the other hand, there seemed to be no apparent change in the blood volume on the SB diluted samples for the various temperature differences between 15-35°C. To conclude, the experiments results were not consistent with predictions of SB simulation model and there are two reasons that could explain that. Firstly, in the simulation the blood was approximated with a homogeneous fluid with a given viscosity. The second reason is the mismatch between the dilution process via the SB and the simulation (the simulation started with an idealized initial status, whereas the SB channel was prefilled by blood). This means that the simulation excluded any effect that may occur as a convection effect during blood flow inside the channel and whilst encountering diluent reagent. These two reasons explain why the results of the simulation was not consistent with that of the experiments, regarding the unwanted blood volume. Therefore, a new simulation is required. Recommendations for future actions: undoubtedly there are several optimizations that may increase the accuracy of the proposed SB design such as; removing the diluent's reservoir for eliminating the effect of bubbles, changing the geometrical angles or use a smaller diameter for the inlets and outlets of the microchannels to reduce the convection and diffusion effect, (which in turn would reduce the unwanted blood volume). Therefore, determining the best SB's microchannel structure to perform the dilution process with minimum unwanted blood volume remains a near future next step follow-up project.

  • 10.
    Alvarez, Victor
    et al.
    KTH.
    Halldin, Peter
    KTH.
    Kleiven, Svein
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    The Influence of Neck Muscle Tonus and Posture on Brain Tissue Strain in Pedestrian Head Impacts2014In: 58th SAE Stapp Car Crash Conference, STAPP 2014, Vol. 58Article in journal (Refereed)
    Abstract [en]

    Pedestrians are one of the least protected groups in urban traffic and frequently suffer fatal head injuries. An important boundary condition for the head is the cervical spine, and it has previously been demonstrated that neck muscle activation is important for head kinematics during inertial loading. It has also been shown in a recent numerical study that a tensed neck musculature also has some influence on head kinematics during a pedestrian impact situation. The aim of this study was to analyze the influence on head kinematics and injury metrics during the isolated time of head impact by comparing a pedestrian with relaxed neck and a pedestrian with increased tonus. The human body Finite Element model THUMS Version 1.4 was connected to head and neck models developed at KTH and used in pedestrian-to-vehicle impact simulations with a generalized hood, so that the head would impact a surface with an identical impact response in all simulations. In order to isolate the influence of muscle tonus, the model was activated shortly before head impact so the head would have the same initial position prior to impact among different tonus. A symmetric and asymmetric muscle activation scheme that used high level of activation was used in order to create two extremes to investigate. It was found that for the muscle tones used in this study, the influence on the strain in the brain was very minor, in general about 1-14% change. A relatively large increase was observed in a secondary peak in maximum strains in only one of the simulated cases. 

  • 11.
    Alvarez, Victor S
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Kleiven, Svein
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Effect of pediatric growth on cervical spine kinematics and deformations in automotive crashes2018In: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 71, p. 76-83, article id S0021-9290(18)30075-7Article in journal (Refereed)
    Abstract [en]

    Finite element (FE) models are a powerful tool that can be used to understand injury mechanisms and develop better safety systems. This study aims to extend the understanding of pediatric spine biomechanics, where there is a paucity of studies available. A newly developed and continuously scalable FE model was validated and scaled to 1.5-, 3-, 6-, 10-, 14- and 18-year-old using a non-linear scaling technique, accounting for local topological changes. The oldest and youngest ages were also scaled using homogeneous geometric scaling. To study the effect of pediatric spinal growth on head kinematics and intervertebral disc strain, the models were exerted to 3.5 g acceleration pulse at the T1 vertebra to simulate frontal, rear and side impacts. It was shown that the head rotation increases with age, but is over predicted when geometrically scaling down from 18- to 1.5-year-old and under predicted when geometrically scaling up from 1.5- to 18-year-old. The strain in the disc, however, showed a clear decrease with age in side impact and for the upper cervical spine in rear impact, indicating a higher susceptibility for neck injury at younger ages. In the frontal impact, no clear age dependence could be seen, suggesting a large contribution from changed facet joint angles, and lower levels of strain, suggesting a lower risk of injury. The results also highlight the benefit of rearward facing children in a seat limiting head lateral motion.

  • 12. Ambort, D.
    et al.
    Johansson, M.E.V.
    Gustafsson, J. K.
    Nilsson, Harriet
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Structural Biotechnology.
    Ermund, A.
    Johansson, B.R.
    Koeck, Philip J. B.
    KTH, School of Technology and Health (STH), Structural Biotechnology (Closed 20130701).
    Hebert, Hans
    KTH, School of Technology and Health (STH), Structural Biotechnology (Closed 20130701).
    Hansson, G.C.
    Calcium and pH-dependent packing and release of the gel-forming MUC2 mucin2012In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 109, no 15, p. 5645-5650Article in journal (Refereed)
    Abstract [en]

    MUC2, the major colonic mucin, forms large polymers by N-terminal trimerization and C-terminal dimerization. Although the assembly process for MUC2 is established, it is not known how MUC2 is packed in the regulated secretory granulae of the goblet cell. When the N-terminal VWD1-D2-D'D3 domains (MUC2-N) were expressed in a goblet-like cell line, the protein was stored together with full-length MUC2. By mimicking the pH and calcium conditions of the secretory pathway we analyzed purified MUC2-N by gel filtration, density gradient centrifugation, and transmission electron microscopy. At pH 7.4 the MUC2-N trimer eluted as a single peak by gel filtration. At pH 6.2 with Ca2+ it formed large aggregates that did not enter the gel filtration column but were made visible after density gradient centrifugation. Electron microscopy studies revealed that the aggregates were composed of rings also observed in secretory granulae of colon tissue sections. TheMUC2-N aggregates were dissolved by removing Ca2+ and raising pH. After release from goblet cells, the unfolded full-length MUC2 formed stratified layers. These findings suggest a model for mucin packing in the granulae and the mechanism for mucin release, unfolding, and expansion.

  • 13.
    Amiri, Fatemeh
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Nouiser, Sara
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Optisk metod för glukosmätning: En studie för framtida icke-invasiva blodglukosmätningar2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today there are currently living around 365 000 people with diabetes in Sweden. Measuring of blood sugar can be experienced as painful and difficult with blood glucose monitoring devices found in the market. Using lancets and test strip makes direct contact with blood which increases the risk of infection. To reduce these risks and difficulties a non-invasive method is required. This method can even provide an opportunity for healthy individuals to monitor their blood glucose and prevent the disease.This thesis presents the disease, sequelae and the problem around blood glucose monitoring. The work is based on an earlier study about optic measurement of glucose. By illumine a solution of saline and glucose, with infrared-light from a LED, absorption is carried out by the glucose. The amount of transmitted light is detected and processed by a photodetector which generates a current that is converted to a voltage and amplified. This report examines a modification of the circuit used in the previous study to establish a correlation between the glucose concentration and the output voltage by adding a transimpedance amplifier around the photodetector.The results corroborate that the modification with the transimpedance gives a better correlation between the measured output voltage and glucose concentration. The measurements were compiled and plotted to compare which circuit gave a better correlation between the measured output voltage and glucose concentration. The study showed that the modification with transimpedance amplifier gives a better correlation, though it is not enough for clinical use.

  • 14.
    Ammendrup, Katrin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Framework for Wireless Acquisition of Surface EMG and Real-Time Control2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Muscle driven devices are controlled or powered with muscle activation. These devices open up the possibility of offering patients with limited muscle function to automatically control assistive devices - for instance exoskeletons - with input from their own muscles. This solution would help a number of patient groups suffering from common conditions, such as spinal cord injuries, stroke and cerebral palsy.

    To use muscle activation as input it is necessary to have a way to communicate with the mus- cles. Electromyography (EMG) is a technology used to gain information about muscle function and activation. It is performed by measuring and analyzing electrical signals conducted by the muscles during activation. Activation and activation level can be seen from analyzed EMG signal. EMG signals are frequently measured and analyzed afterwards, however, to use it as a controlling an assistive devices, real time analysis is necessary. In this thesis real time acquisi- tion and analysis of EMG was performed. The measured signal was used as an input to control a simple MATLAB computer game.

    The EMG of a muscle of the forearm, Brachioradialis, was measured with Myon Aktos sys- tem. The measured signal was written to a server as soon as the measurements were acquired. MATLAB was used to connect to the server and performing the signal analysis. The analysis was kept simple in order to limit delay.

    The result showed that it was possible to acquire real time signal with this method. The delay was negligible, both for the testing and for the game play.

    Showing that it is possible to play a game with muscle activation supports the idea of a motor that can be controlled automatically with muscle input. Future work should focus on understanding movement intent with respect to EMG and on analyzing multiple signals from different muscles at the same time.

  • 15.
    Andersson, Julius
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Engström, David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    A study in how to inject steganographic data into videos in a sturdy and non-intrusive manner2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    It is desirable for companies to be able to hide data inside videos to be able to find the source of any unauthorised sharing of a video. The hidden data (the payload) should damage the original data (the cover) by an as small amount as possible while also making it hard to remove the payload without also severely damaging the cover. It was determined that the most appropriate place to hide data in a video was in the visual information, so the cover is an image. Two injection methods were developed and three methods for attacking the payload. One injection method changes the pixel values of an image directly to hide the payload and the other transforms the image to cosine waves that represented the image and it then changes those cosine waves to hide the payload. Attacks were developed to test how hard it was to remove the hidden data. The methods for attacking the payload where to add and remove a random value to each pixel, to set all bits of a certain importance to 1 or to compress the image with JPEG. The result of the study was that the method that changed the image directly was significantly faster than the method that transformed the image and it had a capacity for a larger payload. The injection methods protected the payload differently well against the various attacks so which method that was the best in that regard depends on the type of attack.

  • 16.
    Anette, Kniberg
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Nokto, David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    A Benchmark of Prevalent Feature Selection Algorithms on a Diverse Set of Classification Problems2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Feature selection is the process of automatically selecting important features from data. It is an essential part of machine learning, artificial intelligence, data mining, and modelling in general. There are many feature selection algorithms available and the appropriate choice can be difficult. The aim of this thesis was to compare feature selection algorithms in order to provide an experimental basis for which algorithm to choose. The first phase involved assessing which algorithms are most common in the scientific community, through a systematic literature study in the two largest reference databases: Scopus and Web of Science. The second phase involved constructing and implementing a benchmark pipeline to compare 31 algorithms’ performance on 50 data sets.The selected features were used to construct classification models and their predictive performances were compared, as well as the runtime of the selection process. The results show a small overall superiority of embedded type algorithms, especially types that involve Decision Trees. However, there is no algorithm that is significantly superior in every case. The pipeline and data from the experiments can be used by practitioners in determining which algorithms to apply to their respective problems.

  • 17.
    Anthony, Diana
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Creating an Individualized Predictive Model of PAO2 and PACO2 Changes During Voluntary Static Apnea for Sedentary Subjects2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The primary aim of this study was to fill a gap in the literature in understanding maximal BH in untrained, non-divers by generating a predictive numerical model for PAO2 and PACO2 throughout BH. There have been little to no previous attempts at explicitly characterizing the influence of impermanent personal or environmental factors on PAO2 or PACO2 at BH breakpoint. The metabolic human consumption of O2 and production of CO2 as measured through alveolar partial pressures was observed over time during a voluntary maximum breath-hold for 18 members of the general population. The coefficient of determination was used to determine accuracy of the model in fitting participants’ BH data from this experiment. The volume of the last inhalation pre-BH, time to subjective breakpoint, and breath-to-breath calculated respiratory exchange ratio (RER) were identified as the most influential combination of key variables that improved PAO2 model fit (from R2 = 0.8591 to R2 = 0.8840). Clustering methods coupled with two sample t-tests or ANOVA were then used to identify survey responses most correlated to inter-BH similarities. These were barometric pressure, age, height, weight, resting HR, smoker/ freediver/scuba experience, and weekly frequency of engaging in physical exercise. The model was validated on testing data from an experienced free-diver, from non-rebreathing trials of a sample of the participants, and from simulated dives of 5 participants from research in the Environmental Physiology Department of Karolinska in 1994 [1]. It has been suggested that the presented model can be a valuable tool in developing safer free diving practices. Furthermore, interesting trends in continuous HR, starting PACO2 values, and O2 consumption were observed and analyzed using statistical analysis. Findings were discussed with connection to the underlying physiological principles that might explain the results obtained.

  • 18.
    Arousell, Anna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Engdahl, Ylva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Can Surface Scanning Improve the Workflow of Elekta Linac Treatments?2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The aim of the project was to compare the workflow for an Elekta Linac with and without the surfacescanning system Catalyst and describe pros and cons with both workflows. The findings in the reportcan be used as decision support in development of Elekta products and workflow improvements.

    The method for the project was to do interviews, observations and time measurements at Södersjukhuset(not using Catalyst) and Sundsvalls sjukhus (using Catalyst). The workflows were graded in an as-sessment protocol covering time efficiency, comfort, noise, resources, reliability, cost, dosage and sideeffects. Different workflow scenarios were simulated in AnyLogic.

    The result of the project was that, according to our protocol, the workflow with Catalyst was ratedhigher than without it. The simulations in Anylogic showed that minimizing gaps in the treatment sched-ule generated the same number of patients treated per day, if the positioning could not be done faster.The simulations also showed that removing position verification with cone beam computer tomography(CBCT), an imaging system which is used in addition to the Catalyst system, would increase the numberof treated patients with approximately 33%.

    The conclusion was that there were no great differences in time efficiency between the workflows. How-ever, considering the higher reliability and comfort for the patient, optical surface scanning can improvethe positioning for Elekta Linac and is therefore worth implementing. Minimizing treatment gaps wouldnot improve the workflow. Removing the use of CBCT would increase the number of treated patientsper day.

  • 19.
    Askfors, Ylva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    Samverkan för innovation: En fallstudie av mötet mellan akademi, industri och sjukvård2018Doctoral thesis, monograph (Other academic)
    Abstract [sv]

    Samverkan kan leda till innovation, konkurrenskraftiga företag, förstklassig forskning samt välfungerande myndigheter och institutioner. I den politiska debatten idag finns en förväntan att Sverige ska upprätthålla sin konkurrenskraft och bemöta samhällets utmaningar genom innovation och att vägen till innovation går via samverkan. Avhandlingen bygger på en studie av ett samverkansprojekt vars syfte var att skapa innovation för att minska antalet vårdrelaterade infektioner i Sverige. Projektet som studerats ses som en transdisciplinär ansats med aktörer som representerade akademi, industri samt hälso- och sjukvård.

    Syftet med avhandlingen är att vidareutveckla kunskapen om interorganisatorisk samverkan för innovation. Detta görs genom ett tredelat bidrag, till teoribildningen kring samverkan för innovation som börjat växa fram, till den samverkande praktiken inom både privat och offentlig sektor samt till politiker och beslutsfattare som styr fördelning av statliga anslag till forskning och innovation.

    Fallstudien som ligger till grund för avhandlingen är baserad på en etnografiskt inspirerad studie. Empiriskt material samlades in och skapades tillsammans med aktörerna i projektet under drygt två års tid genom intervjuer och deltagande observation.

    Studien visar att interorganisatorisk samverkan består av flera dimensioner och kan förstås på flera nivåer. Interorganisatorisk samverkan innebär inte bara att det är olika organisationer som ska göra en gemensam ansträngning. Organisationerna består av olika människor med olika discipliner och professioner vilka bygger på olika utgångspunkter och sätt att se på världen. Samverkan kan ses som ett sätt att fylla mellanrummen mellan organisationer istället för att bygga broar över gränser. I de organisatoriska mellanrummen kan aktörer från olika organisationer, med olika discipliner och professioner mötas utan institutionaliserade roller, i en receptiv kontext där innovation kan skapas.

  • 20.
    Askfors, Ylva
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    Fornstedt, Helena
    Uppsala universitet.
    The clash of managerial and professional logics in public procurement: Implications for innovation in the health-care sector.2018In: Scandinavian Journal of Management, ISSN 0956-5221, E-ISSN 1873-3387, Vol. 34, no 1, p. 78-90Article in journal (Refereed)
    Abstract [en]

    This article addresses the enactment of public procurement and its influence on adoption and diffusion of innovation, using a case study of public procurement of a low-tech medical device innovation in Swedish healthcare. Based on interviews and documentation, the article illustrates the various perspectives of the different professions involved in the complex task of setting the requirement specification for the tender. The technology identities of the medical device (innovation) are constructed and negotiated by the actors: procurement administrators, health-care professionals and suppliers within the adoption space. Examining the enactment of the procurement process as part of the adoption space is a way to deepen our understanding of the social component within public procurement.

  • 21.
    Astaraki, Mehdi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Wang, Chunliang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Buizza, G.
    Toma-Dasu, I.
    Lazzeroni, M.
    Smedby, Örjan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Early survival prediction in non-small cell lung cancer with PET/CT size aware longitudinal pattern2019In: Radiotherapy and Oncology, ISSN 0167-8140, E-ISSN 1879-0887, Vol. 133, p. S208-S209Article in journal (Refereed)
  • 22.
    Astaraki, Mehdi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging. Karolinska Inst, Dept Oncol Pathol, Karolinska Univ Sjukhuset, SE-17176 Stockholm, Sweden.
    Wang, Chunliang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Buizza, Giulia
    Politecn Milan, Dept Elect Informat & Bioengn, Piazza Leonardo da Vinci 42, I-20133 Milan, Italy..
    Toma-Dasu, Iuliana
    Karolinska Inst, Dept Oncol Pathol, Karolinska Univ Sjukhuset, SE-17176 Stockholm, Sweden.;Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden..
    Lazzeroni, Marta
    Karolinska Inst, Dept Oncol Pathol, Karolinska Univ Sjukhuset, SE-17176 Stockholm, Sweden.;Stockholm Univ, Dept Phys, SE-10691 Stockholm, Sweden..
    Smedby, Örjan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Early survival prediction in non-small cell lung cancer from PET/CT images using an intra-tumor partitioning method2019In: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 60, p. 58-65Article in journal (Refereed)
    Abstract [en]

    Purpose: To explore prognostic and predictive values of a novel quantitative feature set describing intra-tumor heterogeneity in patients with lung cancer treated with concurrent and sequential chemoradiotherapy. Methods: Longitudinal PET-CT images of 30 patients with non-small cell lung cancer were analysed. To describe tumor cell heterogeneity, the tumors were partitioned into one to ten concentric regions depending on their sizes, and, for each region, the change in average intensity between the two scans was calculated for PET and CT images separately to form the proposed feature set. To validate the prognostic value of the proposed method, radiomics analysis was performed and a combination of the proposed novel feature set and the classic radiomic features was evaluated. A feature selection algorithm was utilized to identify the optimal features, and a linear support vector machine was trained for the task of overall survival prediction in terms of area under the receiver operating characteristic curve (AUROC). Results: The proposed novel feature set was found to be prognostic and even outperformed the radiomics approach with a significant difference (AUROC(sALop) = 0.90 vs. AUROC(radiomic) = 0.71) when feature selection was not employed, whereas with feature selection, a combination of the novel feature set and radiomics led to the highest prognostic values. Conclusion: A novel feature set designed for capturing intra-tumor heterogeneity was introduced. Judging by their prognostic power, the proposed features have a promising potential for early survival prediction.

  • 23.
    Baban, Hanna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Grauning, Olivia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Using Fetal Myocardial Velocity Recordings to Evaluate an AI Platform to Predict High-risk Deliveries2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    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.

  • 24. Babapour, Maral
    et al.
    Rolfö, Linda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Policies in Activity-based Flexible Offices: ‘I am sloppy with clean-desking. We don’t really know the rules.’2018In: Ergonomics, ISSN 0014-0139, E-ISSN 1366-5847Article in journal (Refereed)
    Abstract [en]

    Activity-based Flexible Offices (A-FOs) are offices with unassigned desks that provide a variety of workspaces. This paper presents desk-sharing and speech rules identified in A-FOs in four Swedish organisations, the emergence of and compliance with these rules, and their consequences for work conditions. Data collection involved 105 semi-structured interviews, document analyses, and observations. The identified rules were: (1) to remove belongings, (2) temporal restrictions on using the same workstations, (3) temporal restrictions on using scarce zones, (4) restrictions on verbal interactions, and (5) restrictions on phone conversations. The cases with extensive user involvement in their planning process had explicit unambiguous rules. A better compliance with rules occurred when (i) the employees were well-prepared and had a unified understanding regarding how and why to follow the rules, (ii) the rules were explicitly communicated and were regarded as easy to follow, and (iii) following the rules facilitated work and improved work conditions.

  • 25.
    Beijner, David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics.
    Ökad lokal nytta av förnyelsebar energiproduktion med hybridkraftverk2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Renewable and environmentally friendly electricity production is a necessity for the relative positive value of the products and processes that consumes electricity. It is not enough that these products and processes in and of themselves are effective in their use of electricity if that electricity is produced with non- renewable means. The goal of this project is the creation of a simulation software that can simulate a hybrid powerplant composed of wind turbines and a hydro powerplant. The result of this project is a simulation software that is able is to approximate the size of a pumped-storage megawatts and the size of the reservoir needed. In addition, the software calculates the amount of wind turbines needed in combination with the hydro powerplant to achieve a desired decrease in non-renewable electricity.

  • 26.
    Bekius, Femke
    et al.
    Delft Univ Technol, Jaffalaan 5, NL-2628 BX Delft, Netherlands..
    Meijer, Sebastiaan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    de Bruijn, Hans
    Delft Univ Technol, Jaffalaan 5, NL-2628 BX Delft, Netherlands..
    Collaboration patterns in the Dutch railway sector: Using game concepts to compare different outcomes in a unique development case2018In: RESEARCH IN TRANSPORTATION ECONOMICS, Vol. 69, p. 360-368Article in journal (Refereed)
    Abstract [en]

    Decision-making on changes to large infrastructural systems is complex. It involves many actors, the system shows unpredictable behaviour and the environment in which decision-making takes place is dynamic. In a unique development case of the Dutch railway sector two decision-making processes regarding the same issue are performed in two consecutive years. Although, from a technical perspective, the elements of the processes are similar, the decisions in each year are different. In this paper, we use game concepts to explain the different outcomes. Other frequently adopted decision-based models that focus on the technical perspective do not distinguish between both processes. Game concepts are able to reveal the hidden actor and context dynamics of the process and provide action perspective. To identify the game concepts present in the decision-making process, we first consider whether these concepts are mentioned in interviews with decision-makers in our case. Thereafter, we interpret the processes using the identified game concepts. The fact that, in the second year, more external issues are discussed and pressure increased created room for another decision.

  • 27.
    Berezkin, Nikita
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Heidari, Ahmed
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Berika receptdata med innehållshanteringssystem2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The problem today is that people do not eat climate-smart food; this results in that the food will not suffice, and what we eat may harm the greenhouse effect. The problem is that people do not have the time or knowledge to cook climate-smart food. A solution is to use a Content Management System (CMS). A Content Management System processes selected type of data in a specific way which is then stored. This report will address the basics and the making of a CMS in a recommendation system for a user. The system will entail a more climate-smart food alternative to achieve the individual's personal needs. The result was that with the help of data from various sources, an ingredient of a recipe could add additional information such as nutritional value, allergies, and whether it is vegetarian. Tests such as performance tests on the execution time for the CMS, parsing accuracy, and matching product accuracy, a better result was achieved. Most of the ingredients in the recipe became enriched, which leads to more climate-smart food alternatives, which are better for the environment. The accuracy is the matching of ingredients in the recipe to the names of products in the business. The next step was to enrich the recipes using enriched ingredients.

  • 28.
    Berglund, Martina
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics. HELIX Competence Centre and Division of Logistics and Quality Management, Linköping University, Linköping, Sweden.
    Arman, Oscar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    From Safety I to Safety II: Applying an HTO Perspective on Supervisory Work Within Aviation2019In: 20th Congress of the International Ergonomics Association, IEA 2018, Springer, 2019, Vol. 821, p. 558-565Conference paper (Refereed)
    Abstract [en]

    In aviation, there is a strong focus on safety to prevent accidents. This paper deals with how supervisory authorities in aviation can apply a Safety II perspective. In particular, the aim is to analyze how the concept of HTO (Humans, Technology, Organization) is related to a possible shift from Safety I to Safety II within supervisory work within aviation. Data for this case study research was collected through semi-structured interviews with inspectors at the civil aviation authority in Sweden. The study showed that the important building stone of proactivity in Safety II could be promoted by the Safety Management System (SMS), the Safety Performance Indicator, and systems for reporting incidents and near-accidents. These systems constituted examples of Technology. Similarly, the Humans consisted of the inspectors, and the Organization included international and national regulations that the inspectors needed to follow during inspections. In the analysis, it was clear that an internal HTO-perspective could be taken. The study indicated that the shift towards Safety II should first be done within the supervisory authority by applying an internal HTO-perspective. This could later be developed to an external HTO-perspective also including the operator organizations.

  • 29.
    Björck, Linnea
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Petersen, Johan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Höjdmätare för fallskärmshoppning: Metoder för höjdmätning samt framtagning av algoritmer för vald metod2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In skydiving, in addition to a well-functioning parachute system, a good and precise altimeter is needed. Both which are crucial parts of equipment in order to be able to perform a safe jump. Through digitalization and the technological development, there are today interests of developing a digital altimeter with better precision and several functions There are a number of techniques for measuring altitude. Those that are included in this bachelor thesis are GPS, radar and barometers.

    The aim of the thesis was to develop a robust algorithm for measuring height, with the possibility of development. The thesis work would also include risk analysis of selected technology or techniques, as well as suggestions for suitable presentation techniques and system solutions in a larger perspective. The system solutions would be adapted for easy integration of new features. If time allowed it, a prototype would also be developed and tested.

    The method chosen was a digital altimeter because it was best suited for the goals set for the project. To calculate the height with the digital altimeter, the relationship between air pressure and height was used. The result of these calculations showed a sufficiently precise measurement value to be acceptable. Since the accuracy of the measurement value was acceptable, it was decided that no further corrections would be made. The work continued with developing a prototype and testing it. The result was a functioning prototype. Future development opportunities are available within presentation technology, chassis, further corrections of the formula for height measurement and more iterations of hardware.

  • 30.
    Boltshauser, Rasmus
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Zheng, Jimmy
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Automatisering av skjuvvågselastografidata för kärldiagnostisk applikation.2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Sammanfattning

     

    Hjärt- och kärlsjukdommar är den ledande dödsorsaken i världen. En av det vanligaste hjärt- och kärlsjukdomarna är åderförkalkning. Sjukdomen kännetecknas av förhårdning samt plackansamling i kärl och bidrar till stroke och hjärtinfarkt. Information om kärlväggens styvhet kan spela en viktig roll vid diagnostiseringen av bland annat åderförkalkning. Skjuvvågselastografi (SWE) är en noninvasiv ultraljudsbaserad metod som idag används för att mäta elasticitet och styvhet av större mjuka vävnader som lever- och bröstvävnad. Dock används inte metoden inom kärlapplikationer, då få genomgående studier har utförts på SWE för kärl. Målet med projektet är att automatisera kvantifieringen av skjuvvågshastigheten för SWE och undersöka hur automatiseringens förmåga och begränsningar beror av automatiseringsinställningar. Med verktyg erhållna från CBH (skolan för kemi, bioteknologi och hälsa) skapades ett MATLAB-program med denna förmåga. Programmet applicerades på två fantommodeller. Automatiseringsinställningarna påverkade automatiseringen av dessa modeller olika, vilket innebar att generella optimala inställningar inte kunde finnas. Optimala inställningar beror på vad automatiseringen skall undersöka.

     

  • 31.
    Borglund, Dan
    et al.
    KTH, School of Industrial Engineering and Management (ITM), Learning.
    Carlsson, Ulf
    KTH, School of Engineering Sciences (SCI).
    Colarieti-Tosti, Massimiliano
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Edström, Simon
    Havtun, Hans
    KTH, School of Industrial Engineering and Management (ITM), Energy Technology, Applied Thermodynamics and Refrigeration.
    Henriksson, Ann-Sofie
    KTH, School of Industrial Engineering and Management (ITM), Learning.
    Hjelm, Niclas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Basic Science.
    Naimi-Akbar, Ida
    KTH, School of Education and Communication in Engineering Science (ECE), Learning, Learning in Engineering Sciences.
    Collaborative Course Evaluation and Development at KTH: Progress, Lessons Learned and Way Forward2017In: 6th USIU Conference, 2017, article id 68Conference paper (Refereed)
  • 32.
    Brusini, Irene
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Carneiro, Miguel
    Univ Porto, Ctr Invest Biodiversidade & Recursos Genet CIBIO, InBIO, P-4485661 Vairao, Portugal.;Univ Porto, Dept Biol, Fac Ciencias, P-4169007 Porto, Portugal..
    Wang, Chunliang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Rubin, Carl-Johan
    Uppsala Univ, Sci Life Lab Uppsala, Dept Med Biochem & Microbiol, S-75236 Uppsala, Sweden..
    Ring, Henrik
    Uppsala Univ, Dept Neurosci, S-75236 Uppsala, Sweden..
    Afonso, Sandra
    Univ Porto, Ctr Invest Biodiversidade & Recursos Genet CIBIO, InBIO, P-4485661 Vairao, Portugal..
    Blanco-Aguiar, Jose A.
    Univ Porto, Ctr Invest Biodiversidade & Recursos Genet CIBIO, InBIO, P-4485661 Vairao, Portugal.;CSIC, Inst Invest Recursos Cineget IREC, Ciudad Real 13005, Spain.;UCLM, CSIC, Ciudad Real 13005, Spain..
    Ferrand, Nuno
    Univ Porto, Ctr Invest Biodiversidade & Recursos Genet CIBIO, InBIO, P-4485661 Vairao, Portugal.;Univ Porto, Dept Biol, Fac Ciencias, P-4169007 Porto, Portugal.;Univ Johannesburg, Dept Zool, ZA-2006 Auckland Pk, South Africa..
    Rafati, Nima
    Uppsala Univ, Sci Life Lab Uppsala, Dept Med Biochem & Microbiol, S-75236 Uppsala, Sweden..
    Villafuerte, Rafael
    CSIC, IESA, Cordoba 14004, Spain..
    Smedby, Örjan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Damberg, Peter
    Karolinska Univ Hosp, Karolinska Expt Res & Imaging Ctr, S-17176 Solna, Sweden..
    Hallbook, Finn
    Uppsala Univ, Dept Neurosci, S-75236 Uppsala, Sweden..
    Fredrikson, Mats
    Uppsala Univ, Dept Psychol, S-75236 Uppsala, Sweden.;Karolinska Inst, Dept Clin Neurosci, S-17177 Stockholm, Sweden..
    Andersson, Leif
    Uppsala Univ, Sci Life Lab Uppsala, Dept Med Biochem & Microbiol, S-75236 Uppsala, Sweden.;Texas A&M Univ, Coll Vet Med & Biomed Sci, Dept Vet Integrat Biosci, College Stn, TX 77843 USA.;Swedish Univ Agr Sci, Dept Anim Breeding & Genet, S-75007 Uppsala, Sweden..
    Changes in brain architecture are consistent with altered fear processing in domestic rabbits2018In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 115, no 28, p. 7380-7385Article in journal (Refereed)
    Abstract [en]

    The most characteristic feature of domestic animals is their change in behavior associated with selection for tameness. Here we show, using high-resolution brain magnetic resonance imaging in wild and domestic rabbits, that domestication reduced amygdala volume and enlarged medial prefrontal cortex volume, supporting that areas driving fear have lost volume while areas modulating negative affect have gained volume during domestication. In contrast to the localized gray matter alterations, white matter anisotropy was reduced in the corona radiata, corpus callosum, and the subcortical white matter. This suggests a compromised white matter structural integrity in projection and association fibers affecting both afferent and efferent neural flow, consistent with reduced neural processing. We propose that compared with their wild ancestors, domestic rabbits are less fearful and have an attenuated flight response because of these changes in brain architecture.

  • 33.
    Buizza, Giulia
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems. Politecnico di Milano, CartCasLab, Department of Electronics Information and Bioengineering, piazza Leonardo Da Vinci 42, Milan 20133, Italy.
    Toma-Dasu, I.
    Lazzeroni, M.
    Paganelli, C.
    Riboldi, M.
    Chang, Yongjun
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Smedby, Örjan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Wang, Chunliang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Early tumor response prediction for lung cancer patients using novel longitudinal pattern features from sequential PET/CT image scans2018In: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 54, p. 21-29Article in journal (Refereed)
    Abstract [en]

    Purpose: A new set of quantitative features that capture intensity changes in PET/CT images over time and space is proposed for assessing the tumor response early during chemoradiotherapy. The hypothesis whether the new features, combined with machine learning, improve outcome prediction is tested. Methods: The proposed method is based on dividing the tumor volume into successive zones depending on the distance to the tumor border. Mean intensity changes are computed within each zone, for CT and PET scans separately, and used as image features for tumor response assessment. Doing so, tumors are described by accounting for temporal and spatial changes at the same time. Using linear support vector machines, the new features were tested on 30 non-small cell lung cancer patients who underwent sequential or concurrent chemoradiotherapy. Prediction of 2-years overall survival was based on two PET-CT scans, acquired before the start and during the first 3 weeks of treatment. The predictive power of the newly proposed longitudinal pattern features was compared to that of previously proposed radiomics features and radiobiological parameters. Results: The highest areas under the receiver operating characteristic curves were 0.98 and 0.93 for patients treated with sequential and concurrent chemoradiotherapy, respectively. Results showed an overall comparable performance with respect to radiomics features and radiobiological parameters. Conclusions: A novel set of quantitative image features, based on underlying tumor physiology, was computed from PET/CT scans and successfully employed to distinguish between early responders and non-responders to chemoradiotherapy. 

  • 34.
    Buizza, Giulia
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems. Politecn Milan, CartCasLab, Dept Elect Informat & Bioengn, Piazza Leonardo Da Vinci 42, I-20133 Milan, Italy..
    Toma-Dasu, Iuliana
    Karolinska Univ Sjukhuset, Karolinska Inst, Dept Oncol Pathol, Med Radiat Phys, S-17176 Solna, Sweden..
    Lazzeroni, Marta
    Karolinska Univ Sjukhuset, Karolinska Inst, Dept Oncol Pathol, Med Radiat Phys, S-17176 Solna, Sweden..
    Paganelli, Chiara
    Politecn Milan, CartCasLab, Dept Elect Informat & Bioengn, Piazza Leonardo Da Vinci 42, I-20133 Milan, Italy..
    Riboldi, Marco
    Politecn Milan, CartCasLab, Dept Elect Informat & Bioengn, Piazza Leonardo Da Vinci 42, I-20133 Milan, Italy.;Ludwig Maximilians Univ Munchen, Fac Phys, Coloumbwall 1, D-5748 Garching, Germany..
    Chang, Yong Jun
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Smedby, Örjan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Wang, Chunliang
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Early tumor response prediction for lung cancer patients using novel longitudinal pattern features from sequential PET/CT image scans2018In: Physica medica (Testo stampato), ISSN 1120-1797, E-ISSN 1724-191X, Vol. 54, p. 21-29Article in journal (Refereed)
    Abstract [en]

    Purpose: A new set of quantitative features that capture intensity changes in PET/CT images over time and space is proposed for assessing the tumor response early during chemoradiotherapy. The hypothesis whether the new features, combined with machine learning, improve outcome prediction is tested. Methods: The proposed method is based on dividing the tumor volume into successive zones depending on the distance to the tumor border. Mean intensity changes are computed within each zone, for CT and PET scans separately, and used as image features for tumor response assessment. Doing so, tumors are described by accounting for temporal and spatial changes at the same time. Using linear support vector machines, the new features were tested on 30 non-small cell lung cancer patients who underwent sequential or concurrent chemoradiotherapy. Prediction of 2-years overall survival was based on two PET-CT scans, acquired before the start and during the first 3 weeks of treatment. The predictive power of the newly proposed longitudinal pattern features was compared to that of previously proposed radiomics features and radiobiological parameters. Results: The highest areas under the receiver operating characteristic curves were 0.98 and 0.93 for patients treated with sequential and concurrent chemoradiotherapy, respectively. Results showed an overall comparable performance with respect to radiomics features and radiobiological parameters. Conclusions: A novel set of quantitative image features, based on underlying tumor physiology, was computed from PET/CT scans and successfully employed to distinguish between early responders and non-responders to chemoradiotherapy.

  • 35.
    Bylerius, Patrik
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Positionering av tågvagn med hjälp av ett Kalmanfilter2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Positioning of railcars is an important part of the railway industry. In Sweden there are 1000 of trains on the railway which leads to a security risk if a railcar is lost.

    This project examined if it were possible to position a railcar in real time using Kalman filter on a raspberry pi with the variable’s latitude and longitude. The project also examined if the Kalman filter could replace an GPS were there was no coverage in that area.

    A prototype was produced and evaluated with a Kalman filter programmed and implemented on it together with a GPS-module. Simulations of several values was made to secure the values that the algorithm did show.

    The prototype shows that the method in this project is within the error margin that the railway demands for a safe system. The results show a deviation of the position that was sought after with the Kalman filter. The coordinates for latitude had a difference of 0,9 m compared to the Kalman filter that was programmed. Longitude also had a difference but with 0,001 m compared to the values that the GPS-module generated.

  • 36.
    Carl, Lind
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Forsman, Mikael
    Institute of Environmental Medicine, Karolinska Institutet, Stockholm, SWEDEN.
    Rose, Linda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Development and evaluation of RAMP I – apractitioner’s tool for screening of musculoskeletaldisorder risk factors in manual handling2019In: International Journal of Occupational Safety and Ergonomics (JOSE), Vol. 25, no 2, p. 165-180, article id 10.1080/10803548.2017.1364458Article in journal (Refereed)
    Abstract [en]

    RAMP I is a screening tool developed to support practitioners in screening for work-related musculoskeletal disorder riskfactors related to manual handling. RAMP I, which is part of the RAMP tool, is based on research-based studies combinedwith expert group judgments. More than 80 practitioners participated in the development of RAMP I. The tool consistsof dichotomous assessment items grouped into seven categories. Acceptable reliability was found for a majority of theassessment items for 15 practitioners who were given 1 h of training. The usability evaluation points to RAMP I beingusable for screening for musculoskeletal disorder risk factors, i.e., usable for assessing risks, being usable as a decision base,having clear results and that the time needed for an assessment is acceptable. It is concluded that RAMP I is a usable toolfor practitioners.

  • 37.
    Chahine, Sandy
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Chowdhury, Selma
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    RTOS med 1.5K RAM?2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Internet of Things (IoT) is becoming more common in today's society. More and more everyday devices are connected to the wireless network. This requires costeffective computing power, which means that it can be beneficial to investigate the microcontroller and how they would cope with this task. These can be seen as smaller compact computers which despite their size offer a lot of performance. This study aims to inform if any existing operating system can work together with the microcontroller PIC18F452 and how many processes that can run in parallel given the MCU's limited memory. A survey and an experiment were conducted to answer these questions.

    Different choice of methods was investigated and discussed to determine which method would generate the best results. A survey and an experiment were conducted to answer these questions. The experiments required a special development environment to be installed and the generic FreeRTOS distribution was ported to both the correct processor and the experimental card. The porting succeeded and experiments showed that the research question could be answered with a yes. You can run a real-time operating system on an MCU with only 1,5 kB RAM memory.

    During the work, the project also found that Amazon built its IoT on FreeRTOS. However, they had invested in a more powerful MCU. The effort would thus emphasize it as a more future-proof approach.

  • 38.
    Chang, Fangyuan
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Technology in Health Care.
    Östlund, Britt
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Technology in Health Care.
    Perspectives of older adults and informal caregivers on information visualization for smart home monitoring systems: A critical review2019In: 20th Congress of the International Ergonomics Association, IEA 2018, Springer, 2019, Vol. 822, p. 681-690Conference paper (Refereed)
    Abstract [en]

    Although health monitoring systems in smart homes have been revealed as a significant tool to help people ageing in place, the density of data poses a challenge on the information visualization. This review aims to make contributions to find gaps in the field of information visualization regarding smart home monitoring for older people. Three kinds of information needs of older adults and their informal caregivers regarding smart home monitoring are categorized, including physical needs, emotional needs and cognitive needs. The research studies reflect that these needs are mainly used to discuss ideas of, design approaches for, the information visualization from ten aspects in the visceral level, behavioral level and reflective level. Results show that there is still a big gap existing in enabling older people and their informal caregivers to better understand smart home monitoring information. Some existing design recommendations can be improved while at the same time, some needs have not been manifested through information visualization. A wider understanding of older adults, informal caregivers and home living environment in all aspects are necessary.

  • 39.
    Chen, Hongjian
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Evangelou, Dimitris
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Grishenkov, Dmitry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging. Karolinska Institutet (KI), CLINTEC – Division of Medical Imaging and Technology.
    Sequence design for ultrasound imaging of polyvinyl alcohol microbubbles2019Conference paper (Refereed)
    Abstract [en]

    Nonlinear behavior of the ultrasound contrast agent (UCA) offers a unique feature to be distinguished from the surrounding tissue. In a recent years several methods were developed to enhance the nonlinear response of UCA. Crucial for efficient differentiation of the nonlinear response of UCA from the surrounding tissue is to design the contrast pulse sequence specific to the unique nonlinear properties that the particular UCA is offering.

    In the previous study, the nonlinear response from a novel polyvinyl alcohol (PVA) microbubbles (MB), in ultra-harmonic region was investigated over a pressure range from 50 kPa to 300 kPa. In this study, five contrast pulse sequences and reference B-mode sequence were designed to visualize PVA MB. The performance of those sequences were evaluated and compared.

  • 40.
    Chen, Hongjian
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Larsson, David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Janerot-Sjöberg, Birgitta
    Colarieti-Tosti, Massimiliano
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Grishenkov, Dmitry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Polymer Microbubbles as Dual Modal Contrast Agent for Ultrasound and Computed Tomography2018Conference paper (Refereed)
    Abstract [en]

    The hybrid imaging combines the anatomical information with the functional or metabolic information using different conventional single imaging modalities improving the overall diagnosis outcome of the clinical examination. Since the introduction of the first hybrid imaging device PET-CT in 1998 different combinations of hybrid imaging were developed such as PET-MRI, SPECT-CT.

    However, lack of multimodal contrast agent specifically aimed for hybrid imaging limits the diagnostic outcome of these novel techniques. Initial attempts in fabrication of hybrid contrast agents were made by combining previously existing single modal contrast agents into one. In this study, polyvinyl alcohol (PVA) microbubbles (MB) and gold nanoparticles - which by themselves are already established contrast agents used in preclinical studies for ultrasound and CT, respectively - were chosen as parent contrast agents to fabricate the dual modal Contrast Agent for UltraSound and CT (CACTUS).

    Method

    The fabrication of MBs was adapted from Cavalieri et al.[1]. PVA powder (Sigma Aldrich, MO USA) was dissolved in the water at 80°C. The aqueous PVA-chains were cleaved by sodium metaperiodate (NaIO4, purity>99.0%, Sigma Aldrich, MO USA). Vigorous stirring force was applied to the resulting telechelic aldehydic PVA-chains for 2 hours to crosslink the telechelic aldehydic PVA-chains and form the PVA-coated MBs at the water-air interface.

    CACTUS MBs were synthesized in a similar fashion to the above, but adding gold nanoparticles (diameter 1.9nm, Nanoprobes, NY, USA) during formation of the MBs.

    The size distributions of MBs and CACATUS MBs were determined using an optical microscope (ECLIPSE Ci-S, Nikon, Tokyo, Japan) and a Neubauer counting chamber (Brand GmbH, Wertheim, Germany).

    The acoustic attenuation coefficients of the MBs suspension were acquired at peak negative pressure (PNP) from 10 - 300 kPa. Three MBs suspension samples with concentrations of (sample A),  (sample B) and  ml-1 (sample C) were prepared and loaded in a 1 cm thick two-cavity chamber. A flat single crystal ultrasound transducer with central frequency 3.5MHz was used to generate the ultrasound beam. The amplitude of received echoes through samples and water were compared at the fundamental frequency, as well as the 2nd and 3rd harmonic for each value of the concentration used.

    The mass attenuation of water, suspension of gold nanoparticles with concentration 160mg/L, plain MBs, and CACTUS MBs, was measured by quantum FX-CT micro-CT (PerkinElmer Inc, MA, USA). The micro-CT was operated at a current of 200mA with exposure time of 120s and varied voltage 50kV, 70kV and 90kV. Each 3D image has a size of 512*512*512 pixels or 75.8*75.8*75.8 mm. Contrast to noise ratios (CNR) between water and all samples were calculated following Eq. 1.Where S(x,y,z) and W(x,y,z) are the mass attenuation of the sample and water per voxel, respectively. ns(x,y,z) and nw(x,y,z) are the noise function with zero mean of sample and water respectively. Ms and Mw are the mean mass attenuation acquired for the sample and water in the volume of interest. The σs2 and σw2 are the variance of the mass attenuation read out of the sample and water in the volume of interested.

    In addition to the gas-core MBs for the CT tests, liquid-core gold loaded capsules were synthesized in two steps. In the first step, PVA shelled liquid-core capsules were obtained by exposing MBs to 66% v/v ethanol solution. In the second step, the resulting liquid-core capsules were mixed with high concentration gold nanoparticles suspension and homogenized by a shaker (MS 3 basic, IKA, Königswinter Germany) at 500rpm for 1 hour for goal loading. The resulting gold loaded capsules were washed with Milli-Q water using centrifuge (Galaxy 5D digital microcentrifuge, VWR, USA) at a speed of 1000 g for 5 min.

    Results and discussion

    The mean diameter of MBs is 3.6±1.1 μm. The mean diameter of CACTUS MBs is 3.2±0.7 μm. The size distribution of the gold loaded capsules was not investigated separately, but rather assumed identical to the plain MBs. The number and the volume distribution of MBs and CACTUS MBs are shown in figure 1. The results demonstrate that most of the CACTUS MBs and MBs have a diameter from 1 to 6 μm. Therefore, they are able pass through the capillaries and will resonate within typical clinical diagnostic ultrasound frequency below 15 MHz.

    Pressure dependent acoustic attenuation coefficients of the sample A, B, and C are shown in figure 2. The results show that attenuation coefficients of sample A and B at the fundamental frequency stay constant and slightly increase at the second harmonic at the PNP below 100kPa, indicating a linear oscillation of MBs. As the PNP reaches 200kPa, the attenuation coefficient of sample A at fundamental frequency decreases while at 2nd and 3rd harmonics increases, indicating that the energy of the echo shifts from the fundamental frequency to the 2nd and 3rd harmonics. As the PNP goes higher to 300kPa, the attenuation coefficient of sample A at the fundamental frequency, 2nd, and 3rd harmonics decreases, suggesting that the energy shifts to an even higher harmonic. At the same time, the attenuation coefficient of sample B stays constant at fundamental frequency, decreases at 2nd harmonics, and increases at the 3rd harmonic, suggesting the energy starts to shift to the 3rd harmonic. The attenuation coefficient of sample C at fundamental frequency, 2nd and 3rd harmonics keep constant and low due to low sample concentration. The test reveals the energy shifting of the echo to the higher harmonics at PNP higher than 100 kPa, indicating the nonlinear oscillation of MBs at PNP higher than 100 kPa. Moreover, the concentration of the MBs seems to influence the energy shifting: the higher the concentration the earlier the shift to the higher harmonics occurs, in the range of the concentration consider in this study.

    The pilot results of the micro-CT tests are presented in Table 1. The reference, gold nanoparticles solution, has the highest CNR per voxel at all CT operating voltages. The CNR per voxel of CACTUS MBs suspensions is below 0.1, virtually equaling the MBs at all operating voltages, suggesting that no gold or very little gold were loaded into the shell of the CACTUS MBs. The gold loaded capsules suspension has higher CNR per voxel than the capsule supernatant (the surrounding environment of capsules) and the MBs suspension, implying that the gold nanoparticles were loaded into the capsules. However, it is not clear whether the gold nanoparticles were loaded in the core of the MBs or in the MBs shell. The expected sharp increase of CNR per voxel at the k-edge of gold did not appear. We believe that is because even at our highest operating voltage of 90kV, the percentage of the photons with energy higher than 80.7 keV is still low. Introduction of a high-pass metal filter could increase the percentage of high energy photon. On the other hand, the metal filter will reduce the total number of the photons which would increase the noise of the images. Since same current was applied on every CT test, less X-ray photons reached the sensors when the CT was operated at low voltage. Therefore, it might be worth performing additional calibration tests to adjust the operating currents to make sure that the numbers of the photons that reach the sensor at every operating voltage are the same.

    Conclusion

    In this study, the CACTUS MBs and gold loaded capsules were fabricated as potential candidates for dual modal contrast agent. The characterization revealed that gold loaded capsule is a promising initial step. Nevertheless, the method to convert back liquid-core capsules to gas-core MBs needs to be established.

    [1] Cavalieri, F., El Hamassi, A., Chiessi, E., Paradossi, G., Villa, R., & Zaffaroni, N. (2006). Tethering functional ligands onto shell of ultrasound active polymeric microbubbles. Biomacromolecules, 7(2), 604-611.

  • 41.
    Chosrat, Ismail
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Joakim, Rödin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    GDPR i praktiken2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Med den nya dataskyddsförordningen (GDPR) i EU ställs det högre krav på hantering avpersonuppgifter och för första gången riskerar företag sanktioner om de inte hanterar personuppgifterkorrekt, vilket medför att alla organisationer måste ta ställning till hur personuppgifterskall hanteras inom organisationen. Inom IT-sektorn måste en analys utföras omvilka data som kommer att påverkas med införandet av GDPR och hur data ska hanteras inuvarande IT-system. Studien har genomförts hos företaget Primona som är placerade iStockholm där de utvecklar lösningar inom inköp och elektronisk handel.Den nya dataskyddsförordningen och relaterade arbeten har studerats tillsammans medintervjuer som utfördes på olika företag för att framställa ett lösningsförslag. Lösningsförslagethar sedan använts i ett implementeringstest i Primonas system för att visa att detfungerar. Studien innehåller även en ekonomisk analys för att fastställa betydelsen av attimplementeringen hanteras och prioriteras.Lösningsförslaget som studien tog fram har gett bevisad effekt i systemet och kan medrelativ lite resurser återanvändas för att säkerställa att en organisation vidtar tillräckligaåtgärder vid införande av GDPR.

  • 42.
    Dahlqvist, Camilla
    et al.
    Lund Univ, Dept Lab Med, Div Occupat & Environm Med, SE-22185 Lund, Sweden..
    Nordander, Catarina
    Lund Univ, Dept Lab Med, Div Occupat & Environm Med, SE-22185 Lund, Sweden..
    Forsman, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Enquist, Henrik
    Lund Univ, Dept Lab Med, Div Occupat & Environm Med, SE-22185 Lund, Sweden..
    Self-recordings of upper arm elevation during cleaning - comparison between analyses using a simplified reference posture and a standard reference posture2018In: BMC Musculoskeletal Disorders, ISSN 1471-2474, E-ISSN 1471-2474, Vol. 19, article id 402Article in journal (Refereed)
    Abstract [en]

    Background To reduce ergonomic risk factors in terms of awkward and constrained postures and high velocities, it is important to perform adequate risk assessments. Technical methods provide objective measures of physical workload. These methods have so far mainly been used by researchers. However, if written instructions how to apply the sensors and how to adopt the reference posture are provided, together with triaxial accelerometers, it may be possible for employees to record their own physical workload. The exposure in terms of e.g. upper arm elevations could then easily be assessed for all workers in a workplace. The main aims of this study were: 1) to compare analyses for self-recording of upper arm elevation during work using a simplified reference posture versus using a standard reference posture, and 2) to compare the two reference postures.MethodsTwenty-eight cleaners attached an accelerometer to their dominant upper arm and adopted a simplified reference according to a written instruction. They were thereafter instructed by a researcher to adopt a standard reference. Upper arm elevations were recorded for 2 or 3 days. Each recording was analysed twice; relative to the simplified reference posture and relative to the standard reference posture. The group means of the differences in recorded upper arm elevations between simplified and standard reference analyses were assessed using Wilcoxon signed ranks test. Furthermore, we calculated the group mean of the differences between the simplified reference posture and the standard reference posture.ResultsFor arm elevation during work (50(th) percentile), the group mean of the differences between the two analyses was 0.2 degrees (range-7 - 10 degrees). The group mean of the differences between the two references was 9 degrees (range 1-21 degrees). The subjects were able to follow the instructions in the protocol and performed self-recording of upper arm elevation and velocity.ConclusionsThe small difference between the two analyses indicates that recordings performed by employees themselves are comparable, on a group level, with those performed by researchers. Self-recordings in combination with action levels would provide employers with a method for risk assessment as a solid basis for prevention of work-related musculoskeletal disorders.

  • 43.
    Dahn, Marcus Anthony
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Weldegiorgish, Hiruy Michael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Utveckling av en interaktiv miljö för inlärning av nya sjukhuslokaler2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    Målet med detta projekt var att simulera den nya byggnaden på Södersjukhuset, ”Operation Pre/Post” för våningsplan 2 och 4. Detta skulle göras på ett sådant sätt att personalen som använde simuleringen kunde lära sig att lokalisera sig i sjukhusavdelningen innan de flyttade dit. För att göra detta möjligt har spelmotorn Unity3D använts, samt ritningar på den nya byggnaden. För att ta reda på om användare av det framtagna spelet verkligen lärde sig att orientera sig i den nya byggnaden, gjordes ett test på Södersjukhusets personal. Detta visade att det är fullt möjligt att få en inlärning av den nya sjukhusbyggnaden med hjälp av det framtagna spelet. Efter en total inlärningstid på cirka 25 minuter, visade läkarna som använt simuleringen en minskning i orienteringstid på 31,6 % i medelvärde. Från början var tanken att simulera båda våningar, men på grund av tidsbrist lyckades bara ett våningsplan skapas. Av denna anledning uppnåddes inte målet helt, vilket innebär att det finns utrymme för framtida arbete inom projektet.

  • 44.
    Danielsson, Jakob
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Oldenburg, Dag
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Analys av tekniska möjligheter för tredjepartsaktörer att integrera med banker2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Banks internet activity have opened new possibilities for third party actors within the fintechindustry who can now create innovative economy and payment solutions by directlyinteracting with bank accounts. A problem for the fintech companies is that there is noavailable information about what technologies are available for them to use to get access tothe banks services and which technology is the most advantageous for their purpose.In this work, the four biggest swedish banks Nordea, Handelsbanken, SEB and Swedbankhave been examined to find out what options third party actors have to integrate with thebanks services. The examination showed that fintech companies will be able to or are able touse one of the three techniques SFTP, REST or web automation. A test environment for thethree technologies was developed to simulate real use cases for fintech companies. CPU-,RAM- and network usage as well as total operating time was measured for the threetechnologies. For sending information REST was the more effective technology when it cameto lower data volumes while SFTP was the most efficient with bigger data volumes. RESTwas the most efficient for retrieving information, no matter the data volume. Web automationwas the least efficient compared to both the other technologies.

  • 45.
    Danko, Charlott
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Hägglund, Stina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Utveckling av en applikation för rullstolsflödet på Karolinska Universitetssjukhuset i Solna2018Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    I dagens samhälle har spårbarhet av medicintekniska hjälpmedel fått en allt viktigare innebörd inom sjukvården. En anledning till det är att de flesta hjälpmedel klassas som medicintekniska produkter vilka enligt Socialstyrelsens föreskrifter måste kunna spåras. Därför märks många hjälpmedel med streckkoder eller liknande markörer. På Karolinska Universitetssjukhuset i Solna önskar man förbättra spårbarheten av rullstolar och få en bättre översikt över vilka som är utlånade och förskrivna.

    En metod för att lösa detta problem är genom att digitalisera flödesprocessen för rullstolar. I det här arbetet har ett digitalt program utvecklats för att ersätta ett antal steg i flödesprocessen som i nuläget hanteras manuellt med penna och papper. Genom att digitalisera delar av processen och se över möjligheter att implementera scanners kan informationen kvalitetssäkras och arbetet effektiviseras. Resultatet visar att ett sådant program som det som utvecklades skulle vara gynnsamt för sjukhuset och skulle bidra till en bättre kontroll över rullstolsflödet. I och med arbetet har en god grund lagts för att digitalisera hanteringen av hjälpmedel och utveckla processerna.

  • 46.
    De Maria, Carmelo
    et al.
    Univ Pisa, Res Ctr E Piaggio, Largo Lucio Lazzarino 1, I-56122 Pisa, Italy.;Univ Pisa, Dept Ingn Informaz, Pisa, Italy..
    Di Pietro, Licia
    Univ Pisa, Res Ctr E Piaggio, Largo Lucio Lazzarino 1, I-56122 Pisa, Italy..
    Lantada, Andres Diaz
    Univ Politecn Madrid, Mech Engn Dept, Madrid, Spain..
    Madete, June
    Kenyatta Univ, Dept Elect & Elect Engn, Nairobi, Kenya..
    Makobore, Philippa Ngaju
    Ugandan Ind Res Inst, Kampala, Uganda..
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Ravizza, Alice
    BioInd Pk Silvano Fumero, Turin, Italy..
    Torop, Janno
    Univ Tartu, Inst Technol, Tartu, Estonia..
    Ahluwalia, Arti
    Univ Pisa, Res Ctr E Piaggio, Largo Lucio Lazzarino 1, I-56122 Pisa, Italy.;Univ Pisa, Dept Ingn Informaz, Pisa, Italy..
    Safe innovation: On medical device legislation in Europe and Africa2018In: Health Policy and Technology, ISSN 2211-8837, E-ISSN 2211-8845, Vol. 7, no 2, p. 156-165Article in journal (Refereed)
    Abstract [en]

    Objectives: The principal motivation for regulating medical devices is to protect patients and users. Complying with regulations may result in an increase in development, manufacturing and service costs for medical companies and ultimately for healthcare providers and patients, limiting the access to adequate medical equipment. On the other hand, poor regulatory control has resulted in the use of substandard devices. This study aims at comparing the certification route that manufactures have to respect for marketing a medical device in some African Countries and in European Union. Methods: We examined and compared the current and future regulations on medical devices in the European Union and in some countries in Africa. Contextually we proposed future approaches to open design strategies supported by emerging technologies as a means to enhance economically sustainable healthcare system driven by innovation. Results: African medical device regulations have an affinity to European directives, despite the fact that the latter are particularly strict. Several states have also implemented or harmonized directives to medical device regulation, or have expressed interest in establishing them in their legislation. Open Source Medical Devices hold a great promise to reduce costs but do need a high level of supervision, to control their quality and to guarantee their respect for safety standards. Conclusion: Harmonization across the two continents could be leveraged to optimize the costs of device manufacture and sale. Regulated open design strategies can enhance economically sustainable innovation. (C) 2018 Fellowship of Postgraduate Medicine.

  • 47. Debevec, T.
    et al.
    Ganse, B.
    Mittag, U.
    Eiken, Ola
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Environmental Physiology. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Centres, Swedish Aerospace Physiology Centre, SAPC.
    Mekjavic, I. B.
    Rittweger, J.
    Hypoxia aggravates inactivity-Related muscle wasting2018In: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 9, no May, article id 494Article in journal (Refereed)
    Abstract [en]

    Poor musculoskeletal state is commonly observed in numerous clinical populations such as chronic obstructive pulmonary disease (COPD) and heart failure patients. It, however, remains unresolved whether systemic hypoxemia, typically associated with such clinical conditions, directly contributes to muscle deterioration. We aimed to experimentally elucidate the effects of systemic environmental hypoxia upon inactivity-related muscle wasting. For this purpose, fourteen healthy, male participants underwent three 21-day long interventions in a randomized, cross-over designed manner: (i) bed rest in normoxia (NBR; PiO2 = 133.1 ± 0.3 mmHg), (ii) bed rest in normobaric hypoxia (HBR; PiO2 = 90.0 ± 0.4 mmHg) and ambulatory confinement in normobaric hypoxia (HAmb; PiO2 = 90.0 ± 0.4 mmHg). Peripheral quantitative computed tomography and vastus lateralis muscle biopsies were performed before and after the interventions to obtain thigh and calf muscle cross-sectional areas and muscle fiber phenotype changes, respectively. A significant reduction of thigh muscle size following NBR (-6.9%, SE 0.8%; P < 0.001) was further aggravated following HBR (-9.7%, SE 1.2%; P = 0.027). Bed rest-induced muscle wasting in the calf was, by contrast, not exacerbated by hypoxic conditions (P = 0.47). Reductions in both thigh (-2.7%, SE 1.1%, P = 0.017) and calf (-3.3%, SE 0.7%, P < 0.001) muscle size were noted following HAmb. A significant and comparable increase in type 2× fiber percentage of the vastus lateralis muscle was noted following both bed rest interventions (NBR = +3.1%, SE 2.6%, HBR = +3.9%, SE 2.7%, P < 0.05). Collectively, these data indicate that hypoxia can exacerbate inactivity-related muscle wasting in healthy active participants and moreover suggest that the combination of both, hypoxemia and lack of activity, as seen in COPD patients, might be particularly harmful for muscle tissue.

  • 48. Dellve, Lotta
    et al.
    Andréasson, Jörgen
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Jutengren, G.
    Hermansson, J.
    How can support resources support sustainable leadership in healthcare?2018In: Article in journal (Refereed)
  • 49.
    Dillon-Murphy, Desmond
    et al.
    Kings Coll London, Sch Biomed Engn & Imaging Sci, London, England..
    Marlevi, David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Ruijsink, Bram
    Kings Coll London, Sch Biomed Engn & Imaging Sci, London, England..
    Qureshi, Ahmed
    Kings Coll London, Sch Biomed Engn & Imaging Sci, London, England..
    Chubb, Henry
    Stanford Univ, Dept Cardiothorac Surg, Palo Alto, CA 94304 USA..
    Kerfoot, Eric
    Kings Coll London, Sch Biomed Engn & Imaging Sci, London, England..
    O'Neill, Mark
    Kings Coll London, Sch Biomed Engn & Imaging Sci, London, England..
    Nordsleffen, David
    Kings Coll London, Sch Biomed Engn & Imaging Sci, London, England..
    Aslanidi, Oleg
    Kings Coll London, Sch Biomed Engn & Imaging Sci, London, England..
    de Vecchi, Adelaide
    Kings Coll London, Sch Biomed Engn & Imaging Sci, London, England..
    Modeling Left Atrial Flow, Energy, Blood Heating Distribution in Response to Catheter Ablation Therapy2018In: Frontiers in Physiology, ISSN 1664-042X, E-ISSN 1664-042X, Vol. 9, article id 1757Article in journal (Refereed)
    Abstract [en]

    Introduction: Atrial fibrillation (AF) is a widespread cardiac arrhythmia that commonly affects the left atrium (LA), causing it to quiver instead of contracting effectively. This behavior is triggered by abnormal electrical impulses at a specific site in the atrial wall. Catheter ablation (CA) treatment consists of isolating this driver site by burning the surrounding tissue to restore sinus rhythm (SR). However, evidence suggests that CA can concur to the formation of blood clots by promoting coagulation near the heat source and in regions with low flow velocity and blood stagnation. Methods: A patient-specific modeling workflow was created and applied to simulate thermal-fluid dynamics in two patients pre- and post-CA. Each model was personalized based on pre- and post-CA imaging datasets. The wall motion and anatomy were derived from SSFP Cine MRI data, while the trans-valvular flow was based on Doppler ultrasound data. The temperature distribution in the blood was modeled using a modified Pennes bioheat equation implemented in a finite-element based Navier-Stokes solver. Blood particles were also classified based on their residence time in the LA using a particle-tracking algorithm. Results: SR simulations showed multiple short-lived vortices with an average blood velocity of 0.2-0.22 m/s. In contrast, AF patients presented a slower vortex and stagnant flow in the LA appendage, with the average blood velocity reduced to 0.08-0.14 m/s. Restoration of SR also increased the blood kinetic energy and the viscous dissipation due to the presence of multiple vortices. Particle tracking showed a dramatic decrease in the percentage of blood remaining in the LA for longer than one cycle after CA (65.9 vs. 43.3% in patient A and 62.2 vs. 54.8% in patient B). Maximum temperatures of 76 degrees and 58 degrees C were observed when CA was performed near the appendage and in a pulmonary vein, respectively. Conclusion: This computational study presents novel models to elucidate relations between catheter temperature, patient-specific atrial anatomy and blood velocity, and predict how they change from SR to AF. The models can quantify blood flow in critical regions, including residence times and temperature distribution for different catheter positions, providing a basis for quantifying stroke risks.

  • 50.
    Domkin, Dmitry
    et al.
    Univ Gavle, Fac Hlth & Occupat Studies, Dept Occupat & Publ Hlth Sci, Ctr Musculoskeletal Res, S-80176 Gavle, Sweden..
    Forsman, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Richter, Hans O.
    Univ Gavle, Fac Hlth & Occupat Studies, Dept Occupat & Publ Hlth Sci, Ctr Musculoskeletal Res, S-80176 Gavle, Sweden..
    Effect of ciliary-muscle contraction force on trapezius muscle activity during computer mouse work2019In: European Journal of Applied Physiology, ISSN 1439-6319, E-ISSN 1439-6327, Vol. 119, no 2, p. 389-397Article in journal (Refereed)
    Abstract [en]

    The present study aimed to identify whether or not an increase in ciliary-muscle contraction force, when the eye-lens is adjusted for viewing at a near distance, results in an increase in trapezius muscle activity, while performing a natural work task. Twelve participants, ranging in age from 21 to 32years, performed a computer-mouse work task during free gaze conditions. A moving visual target was tracked with a computer mouse on a screen placed at two different distances from the eyes, 25cm and 50cm. Tracking performance, eye accommodation, and bilateral trapezius muscle activity were measured continuously. Ciliary-muscle contraction force was computed according to a formula which takes into account the age-dependent, non-linear relationship between the contraction force of the ciliary muscle and the produced level of eye accommodation. Generalized estimating equations analyses were performed. On the dominant hand side and for the nearest screen distance, there was a significant effect of ciliary-muscle contraction force on the trapezius muscle activity (p<0.001). No other effects were significant (p>0.05). The results support the hypothesis that high visual demands, during computer mouse work, increase ciliary muscle contraction force and contribute to a raise of the sustained level of trapezius muscle activity. The current study specifically clarifies the validity of the relationship between ciliary-muscle contraction force and trapezius muscle activity and demonstrates that this relationship is not due to a general personality trait. We conclude that a high level of ciliary muscle contraction force can contribute to a development of musculoskeletal complaints in the neck-shoulder area.

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