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  • 1.
    Abtahi, Farhad
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Lindecrantz, Kaj
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Seoane, Fernando
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Aslamy, Benjamin
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Boujabir, Imaneh
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    An Affordable ECG and Respiration Monitoring System Based on Raspberry PI and ADAS1000: First Step towards Homecare Applications2015In: 16th Nordic-Baltic Conference on Biomedical Engineering: 16. NBC & 10. MTD 2014 joint conferences. October 14-16, 2014, Gothenburg, Sweden, Springer, 2015, p. 5-8Conference paper (Refereed)
    Abstract [en]

    Homecare is a potential solution for problems associated with an aging population. This may involve several physiological measurements, and hence a flexible but affordable measurement device is needed. In this work, we have designed an ADAS1000-based four-lead electrocardiogram (ECG) and respiration monitoring system. It has been implemented using Raspberry PI as a platform for homecare applications. ADuM chips based on iCoupler technology have been used to achieve electrical isolation as required by IEC 60601 and IEC 60950 for patient safety. The result proved the potential of Raspberry PI for the design of a compact, affordable, and medically safe measurement device. Further work involves developing a more flexible software for collecting measurements from different devices (measuring, e.g., blood pressure, weight, impedance spectroscopy, blood glucose) through Bluetooth or user input and integrating them into a cloud-based homecare system.

  • 2.
    Abtahi, Farhad
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Seoane, Fernando
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Lindecrantz, Kaj
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Electrical bioimpedance spectroscopy in time-variant systems: Is undersampling always a problem?2014In: Journal of Electrical Bioimpedance, E-ISSN 1891-5469, Vol. 5, no 1, p. 28-33Article in journal (Refereed)
    Abstract [en]

    During the last decades, Electrical Bioimpedance Spectroscopy (EBIS) has been applied mainly by using the frequency-sweep technique, across a range of many different applications. Traditionally, the tissue under study is considered to be time-invariant and dynamic changes of tissue activity are ignored by treating the changes as a noise source. A new trend in EBIS is simultaneous electrical stimulation with several frequencies, through the application of a multi-sine, rectangular or other waveform. This method can provide measurements fast enough to sample dynamic changes of different tissues, such as cardiac muscle. This high sampling rate comes at a price of reduction in SNR and the increase in complexity of devices. Although the frequency-sweep technique is often inadequate for monitoring the dynamic changes in a variant system, it can be used successfully in applications focused on the time-invariant or slowly-variant part of a system. However, in order to successfully use frequency-sweep EBIS for monitoring time-variant systems, it is paramount to consider the effects of aliasing and especially the folding of higher frequencies, on the desired frequency e.g. DC level. This paper discusses sub-Nyquist sampling of thoracic EBIS measurements and its application in the case of monitoring pulmonary oedema. It is concluded that by considering aliasing, and with proper implementation of smoothing filters, as well as by using random sampling, frequency-sweep EBIS can be used for assessing time-invariant or slowly-variant properties of time-variant biological systems, even in the presence of aliasing. In general, undersampling is not always a problem, but does always require proper consideration.

  • 3.
    Adolfsson, Lars
    Linköping University, Department of Clinical and Experimental Medicine, Division of Surgery, Orthopedics and Oncology. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Center for Surgery, Orthopaedics and Cancer Treatment, Department of Orthopaedics in Linköping.
    Post-traumatic stiff elbow2018In: EFORT open reviews, ISSN 2058-5241, Vol. 3, no 5, p. 210-216Article, review/survey (Refereed)
    Abstract [en]

    Post-traumatic and post-operative stiffness of the elbow joint is relatively common and may in pronounced cases markedly interfere with normal upper extremity function.Soft-tissue contractures and heterotopic bone formation are two major causes of limited movement.Extensive recent research has elucidated many of the pathways contributing to these conditions, but the exact mechanisms are still unknown.In the early phase of soft-tissue contractures conservative treatment may be valuable, but in longstanding cases operative treatment is often necessary.Several different options are available depending on the severity of the condition and the underlying offending structures. Surgical treatment may allow significant gains in movement but rarely complete restoration, and complications are not uncommon.The following presentation reviews the recent literature on pathomechanisms and treatment alternatives. Cite this article: EFORT Open Rev 2018;3 DOI: 10.1302/2058-5241.3.170062.

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  • 4.
    Ahlström, Christer
    et al.
    Linköping University, Department of Biomedical Engineering.
    Liljefeldt, Olle
    Hult, Peter
    Linköping University, Department of Biomedical Engineering.
    Ask, Per
    Linköping University, Department of Biomedical Engineering.
    Heart sound cancellation from lung sound recordings using recurrence time statistics and nonlinear prediction.2005In: Medicinteknikdagarna, 2005, Vol. 12, p. 812-815Conference paper (Other academic)
    Abstract [en]

    Heart sounds (HS) obscure the interpretation of lung sounds (LS). This letter presents a new method to detect and remove this undesired disturbance. The HS detection algorithm is based on a recurrence time statistic that is sensitive to changes in a reconstructed state space. Signal segments that are found to contain HS are removed, and the arising missing parts are replaced with predicted LS using a nonlinear prediction scheme. The prediction operates in the reconstructed state space and uses an iterated integrated nearest trajectory algorithm. The HS detection algorithm detects HS with an error rate of 4% false positives and 8% false negatives. The spectral difference between the reconstructed LS signal and an LS signal with removed HS was 0 34 0 25, 0 50 0 33, 0 46 0 35, and 0 94 0 64 dB/Hz in the frequency bands 20–40, 40–70, 70–150, and 150–300 Hz, respectively. The cross-correlation index was found to be 99.7%, indicating excellent similarity between actual LS and predicted LS. Listening tests performed by a skilled physician showed high-quality auditory results.

  • 5.
    Ahmed, Masud Omar
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Teststation för industriella UV-celler2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    GE Healthcare Bio-Sciences AB in Umeå produce a variety of chromatography systems. One of the main components in chromatography is the UV module, which measure the light absorption of different wavelengths in the liquid being pumped through a cell. Currently at the Umeå site two types of UV-cells are produced; lab cells and industrial cells. The current test station for the industrial UV-cells is outdated, in disrepair and no longer supported.  GE has developed a test station for the lab cells that evaluates UV and flow properties, the data is stored in GE’s own production database, Prodas.

    The aim of this work is to design a test station for industrial UV-cells to improve the quality of the cells. The primary goal is a test station that can measure pressure, flow and absorption. The secondary goal is to discover and if possible, implement solutions that will streamline and automate the test station.

    A prototype of a test station for industrial UV-cells based on that for lab cells has been developed. The solution consists of an adapter that links the light path from the monitor through the UV-cell to the detector. The test station can measure pressure, flow and absorption but can only perform absorption and leakage tests.  Automation and efficiency have been accomplished in the form of scripts used to conduct absorption and leakage tests. The test station requires further development before it can be used in the production line.

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  • 6.
    Al Kouatli, Hakim
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Nanotechnology and Functional Materials.
    Achmawi, Mohamed
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Nanotechnology and Functional Materials.
    Utvärdering av en befintlig plattform för neurofeedback med hjälp av open-source EEG2022Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Neurofeedback is a type of biofeedback in which subjects learn to use the activity of their own electrical brain waves to respond to a visual or auditory feedback from the activity of the brain. This is done by connecting electrodes to the body to get the brain's electrical activity in the form of encephalogram signals (EEG) which are then calculated and converted into useful feedback.The purpose of this work was to evaluate a neurofeedback platform via an OpenBCI open-source EEG technology that could lead to more accessible neurofeedback for society.This study was conducted with different methods where the focus was on testing and data analysis. The study has included a summary of theory used in neurofeedback, a comprehensive pilot study on an 8-channel open-source EEG neurofeedback platform and some of the ethical aspects behind the technology used and neurofeedback in Sweden. During the work, two different experts were interviewed: Gunilla Radu, founder and owner of Nordic Center of Neurofeedback AB and Jan Rutkowski, who is an engineer in medical engineering at the Uppsala Hospital.The tests with 8-channel EEG with an OpenBCI hardware and software show results from three subjects. The answers from a follow-up survey that subjects were allowed to answer are presented in the report. This was used as an evaluation of the tests performed. The aim of the tests was to give Biohackeri an opportunity to see the potential for a neurofeedback platform and to create a basis for further development of such a platform. The result indicates that a measurement of the brain activity at rest with the technology from OpenBCI shows a higher concentration level in the human body with open eyes compared to closed eyes. In addition, a higher level of relaxation is noticed when resting with eyes closed compared to eyes open. Answers from the survey show that what is important to the test subjects is, among other things, the convenience while testing the technology. In terms of requirements and rules that Neurofeedback therapists must meet, it turned out that in Sweden therapists do not need to have a specific background or education. There are ethical perspectives that Neurofeedback therapists may consider in implementing Neurofeedback Therapy.The conclusion of this project is that the tested 8-channel EEG equipment gives a result that agrees with the presented theory. Thus, a Neurofeedback platform could be built on the commercially available open-source technology, such as the technology from OpenBCI.

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    Utvärdering av en befintlig plattform för neurofeedback med hjälp av open-source EEG
  • 7.
    Alonso Orozco, Fabiola
    Linköping University, Department of Biomedical Engineering. Linköping University, The Institute of Technology.
    Finite Element Method Modelling and Simulations for Comparisonbetween Deep Brain Stimulation Electrodes2012Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Deep Brain Stimulation (DBS) is an invasive therapy that alleviates the symptoms of several neurological disorders by electrically stimulating specific regions of the brain, generally within the basal ganglia. Until now Medtronic DBS system is the only approved by the Food and Drug Administration, nevertheless European and Australian countries  have recently approved St. Jude DBS systems to treat Parkinson’s disease and related movement disorders.

         Traditionally, voltage-controlled stimulation (the type of systems provided by Medtronic) has been used and clinicians are familiar with its settings; however the knowledge about systems based in current-controlled stimulation (St. Jude systems) is rather scarce. One of the key factors for a successful therapy is the optimal selection of the electrical parameters for stimulation. Due to the critical zone where the surgery is performed, modeling and simulations of DBS systems have been extensively used to observe how the electric field is distributed in the brain tissue and ultimately to help the clinicians to select the best parameters.

         In this thesis two finite element models of the DBS systems mentioned above have been developed; five examinations were designed, based on the physical and electrical differences between the systems, to observe and quantitatively compare the electric field distribution.

        The aim of this thesis was to investigate the differences between two representative models of each company but moreover to contribute with information regarding current-controlled stimulation.

    The results obtained are expected to be useful for further investigations where the magnitude and distribution of the electric field generated by this type of electrodes are needed.

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    Finite Element Method Modelling and Simulations for Comparisonbetween Deep Brain Stimulation Electrodes
  • 8.
    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.

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  • 9.
    Andersson, David
    Linköping University, Department of Biomedical Engineering.
    Real-time ECG for objective stress level measurement2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Today’s endeavor of performance and accomplishment might bring more efficiency in many ways, but it has a price. Stress related diseases have increased in numbers the last decades and the field of stress is an exceptionally live issue. Linkura is a company which partly works towards identifying and decreasing stress. To be able to monitor and detect stress in people’s daily life, an ECG-device is used.

    This thesis is divided into two parts. The first part consisted of analyzing and comparing four different ECG based stress measures. These stress measures were RMSSD, Heart Rate, high frequency (HF) band and ratio between low and high frequency bands (LF/HF), last two based in frequency domain. These were taken from healthy test subjects for periods of relaxation where the stress level presumably would decrease. What could be seen for all measures was that they all showed a statistical significant decrease in stress level (p<0.05) during the relaxation period. LF/HF ratio was the one performing best and showed clearest decrease in stress.

    Biofeedback is a growing treatment, or rather, health monitoring, which purpose is to gain awareness of physiological functions to manipulate them at will. The second part of the thesis compared two ECG-related respiratory components, to find out which one would be most suited for biofeedback purpose to lower stress in the form of breathing exercises. The two respiratory components investigated were beat to beat heart rate and R-peak amplitude. For this part, a real-time application in the form of a mobile application was created and connected to the ECG-device. This enabled real-time measurement, which was crucial for the second part. Different time and frequency based algorithms were made to compare the two respiratory components. What could be seen was that the beat to beat heart rate signal was the respiratory component following breathing pattern the most.

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  • 10.
    Andersson, Simon
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Designing a fast and robust device for measuring and providing graphical visualization of the number of 60Co sources in a Leksell Gamma Knife®2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The Leksell Gamma Knife® (LGK) is a device for performing radiosurgery. The LGK contains approximately 200 radioactive sources whose beams intersect in a focal point in order to treat brain tumours. Quality assurance tools are used at Elekta to indirectly assess the number of sources in an LGK from the total amount of radiation. In order to increase patient safety, regulatory agencies have been asking for evidential proof of the number of sources in the LGK. This thesis' goal is to directly measure each source in the LGK and optimize the total detection time. To do this, a source detection system was developed with two parts, a radiation detection system and a moving gantry. Initial tests of the design were performed at Elekta and a final test was performed on an LGK at Karolinska Universitetssjukhuset. The results show that the proposed design has the possibility of detecting all sources in an LGK.

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    Simon_Andersson_Student_Thesis
  • 11.
    Angelopoulos, Angelos
    et al.
    -.
    Apostolakis, A.
    -.
    Aslanides, E.
    -.
    Backenstoss, Gerhard
    -.
    Bargassa, P.
    -.
    Bee, C P.
    -.
    Behnke, O.
    -.
    Benelli, A.
    -.
    Bertin, V.
    -.
    Blanc, F.
    -.
    Danielsson, Mats
    KTH, Superseded Departments (pre-2005), Physics.
    Physics at CPLEAR2003In: Physics Reports, Vol. 374, no 3, p. 165-270Article in journal (Refereed)
    Abstract [en]

    LEAR offered unique opportunities to study the symmetries which exist between matter and antimatter. At variance with other approaches at this facility, CPLEAR was an experiment devoted to the study of CP, T and CPT symmetries in the neutral-kaon system. A variety of measurements allowed us to determine with high precision the parameters which describe the time evolution of the neutral kaons and their antiparticles, including decay amplitudes, and the related symmetry properties. Limits concerning quantum-mechanical predictions (EPR, coherence of the wave function) or the equivalence principle of general relativity have been obtained. An account of the main features of the experiment and its performances is given here, together with the results achieved.

  • 12. Apostolakis, A
    et al.
    Aslanides, E.
    -.
    Backenstoss, G.
    -.
    Bargassa, P.
    -.
    Behnke, O.
    -.
    Benelli, A.
    -.
    Bertin, V.
    -.
    Blanc, F.
    -.
    Bloch, P.
    -.
    Carlson, P.
    KTH, School of Engineering Sciences (SCI).
    Danielsson, Mats
    KTH, Superseded Departments (pre-2005), Physics.
    A determination of the CP violation parameter η+- from the decay of strangeness-tagged neutral kaons1999In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 458, no 4, p. 545-552Article in journal (Refereed)
    Abstract [en]

    LEAR offered unique opportunities to study the symmetries which exist between matter and antimatter. At variance with other approaches at this facility, CPLEAR was an experiment devoted to the study of CP, T and CPT symmetries in the neutral-kaon system. A variety of measurements allowed us to determine with high precision the parameters which describe the time evolution of the neutral kaons and their antiparticles, including decay amplitudes, and the related symmetry properties. Limits concerning quantum-mechanical predictions (EPR, coherence of the wave function) or the equivalence principle of general relativity have been obtained. An account of the main features of the experiment and its performances is given here, together with the results achieved.

  • 13.
    Arnlund, Caroline
    Umeå University, Faculty of Science and Technology, Department of Applied Physics and Electronics.
    Utveckling av sensor för mätning av hjärtaktivitet2014Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Motion analysis is a necessary tool when it comes to evaluation, monitoring and diagnosis of all the diseases that affect the human musculoskeletal system. There are only a few clinical walking laboratories in Sweden, where the patients can receive a more detailed and objective evaluation of their walking patterns. The problem with these laboratories is that they are relatively expensive and resource-demanding.

    The department of research and development at NUS has initiated a research project where AnyMo, a mobile system for measuring of moving patterns, was produced. The aim of this thesis was to further develop the existing system to simultaneously measure the electrical activity of the heart (ECG).

    The parts that were constructed during this project was an ECG sensor and a Master Unit, coupled to an existing motion sensor (part of the AnyMo system). The information that was collected from these sensors was stored locally in a memory on the system’s Master Unit.

    The finished product was tested and evaluated on a stationary bike at different pace and heart rate.

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    Utveckling av sensor för mätning av hjärtaktivitet
  • 14.
    Attemalm, Nils
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Applied Mechanics.
    Påverkan av utloppsrörets längd i en automatiskt självtömmande hävert och komponenternas påverkan på tömningshastigheten2023Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    To facilitates tasks in modern healthcare, innovative solutions can be used and the product Sippi is an example of this. Sippi is a self-emptying siphon device used for monitoring a patient ́s urine production. This report examines one of the two main components of Sippi, known as the disposable unit. The unit consist of a siphon which is self-emptying without needing any mechanical assistance. The purpose of the report is to understand how some vital components of Sippi affect the emptying rate and determine the optimal length of the outlet tube. Theoretical calculations and experiential methods are used for the investigation. From the data and with help of software from Observe Medical, results could be generated in various forms, leading to several conclusions. The examined components, which were the bell and the filter had a negative effect on the emptying rate, resulting in a decreased rate when in use. Regarding the pressure drop, it was concluded that longer pipes generated greater pressure drop across the pipe. Additional studies are required to establish the ideal length of the outlet tube.

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  • 15.
    Augustine, Robin
    Uppsala University.
    A Preliminary Study on Skin Burn Degree Analysis Based on Coupling Effect between Burn Area and Micro Strip Ring Resonator2016Conference paper (Refereed)
  • 16. Augustine, Robin
    Chitosan Biopolymer for Microwave Tomography Applications2008Conference paper (Refereed)
  • 17. Augustine, Robin
    Complex dielectric permittivity measurements of human skin and biological solution in2-67GHz range2012Conference paper (Refereed)
  • 18.
    Augustine, Robin
    Uppsala University.
    COmplex Fracture Orthopedic RehabiliTation – COMFORT2016Conference paper (Refereed)
  • 19.
    Augustine, Robin
    Uppsala University.
    Experimental procedure for determination of the dielectric properties of biological samples in the 2-50 GHz range2014In: IEEE Journal of Translational Engineering in Health and Medicine, E-ISSN 2168-2372Article in journal (Refereed)
  • 20. Augustine, Robin
    Human skin permittivity models for the millimeter-wave range2011In: IET Electronics Letters, Vol. 47, p. 427-428Article in journal (Refereed)
    Abstract [en]

    The complex permittivity of the human skin has been measured in vivo in the 10 –60 GHz range using a recently developed coaxial slim probe. The results are compared with the literature data at millimetre waves, and a broad-band Cole-Cole model is proposed for several locations on the arm, namely at the palm, wrist, and forearm. This reported study provides relevant data required for studying interactions between emerging body-centric wireless millimetre-wave technologies and the human body

  • 21.
    Augustine, Robin
    Uppsala University.
    Microwave antenna for analysis of mineralization in cranial vaults2015Conference paper (Other academic)
  • 22.
    Augustine, Robin
    Uppsala University.
    Monitoring weight bearing in an ambulant setting: the SensiStep2016Conference paper (Refereed)
  • 23.
    Augustine, Robin
    Uppsala University.
    Phantom models for human hip and thigh2016Conference paper (Refereed)
  • 24. Augustine, Robin
    Polymeric ferrite-loaded antennas for on-body communications2009In: Microwave and Optical technology Letters, Vol. 51, no 11Article in journal (Refereed)
    Abstract [en]

    Wearable antennas are integral part of body area networks (BANs). Antenna design for BAN applications is a challenging task since the antennas have to be small, efficient, and must not be affected by the wearer's body. This makes isolation of antenna a matter of importance. Ferrites form an opaque media for microwave at the 2.4-GHz ISM band and hence it could be used for the isolation of antenna from surroundings. Thin polymeric ferrite sheets are used to reduce body influence in BAN perspective.

  • 25.
    Augustine, Robin
    Uppsala University.
    Transverse Electromagnetic cell for Biological cell exposure studies Sujith2016Conference paper (Refereed)
  • 26.
    Augustine, Robin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Kurup, Dhanesh G.
    Amrita Vishva Vidyapeetham Univ, Dept Elect & Commun, Bangalore, Karnataka, India.
    Raman, Sujith
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Lee, Dujin
    Gwangju Inst Sci & Technol, Dept Med Syst Engn, Gwangju, South Korea.
    Kim, K. Kangwook
    Gwangju Inst Sci & Technol, Sch Informat & Mechatron, Gwangju, South Korea.
    Rydberg, Anders
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Bone Mineral Density Analysis using Ultra Wideband Microwave Measurements2015Conference paper (Refereed)
    Abstract [en]

    A novel approach to analyze the bone mineral density (BMD) based on microwave reflectivity analysis is presented in this paper. The proposed method enables us to overcome the health risks associated with diagnostic techniques such as X-rays for repeated study of the rate of mineralization in the case of fractures or de-mineralization in the case of osteoporosis. In this paper, we demonstrate the application of Microwaves for continuous observation of skull healing process during post-cranial surgery period. The proposed technique can be a potential clinical model in future for extracting target characteristics such as bone deposition thickness and other cranial defects. Based on the conclusions of wideband measured data, we propose to design the Transceiver using ultra wideband (UWB) pulsed technology.

  • 27.
    Axelson, Mattias
    Linköping University, Department of Biomedical Engineering.
    A Physiological investigation of Rest in Commercial Long-Haul Truck Drivers2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The development of automated vehicles is something most vehicle manufacturers are working on these days. Different levels of automation allow the driver to perform other tasks while traveling than focus on the dynamic driving tasks. For professional drivers where there are strict laws for the amount of driving hours that is allowed without stopping and taking a break, resting while the vehicle is in an automated driving mode can increase the transport efficiency and the comfort of the driver.

    With data collected from 11 professional long-haul truck drivers in the ADAS&ME project, the goal of this thesis is to investigate if it is possible to obtain rest during autonomous driving (simulated with a confederate driver).

    Pre- and post-drive tests, KSS and SUS ratings, HRV features obtained from ECG data and blink features obtained from vertical EOG data was used in order to evaluate if rest could be obtained during simulated autonomous driving compared to normal driving.

    The results show that no clear trends or statistically significant differences can be seen while comparing simulated autonomous driving with normal driving. However one of the participants showed indications in KSS and SUS ratings together with the HRV features that rest was obtained during the simulated autonomous driving.

    The results indicate that it could be possible to obtain rest during autonomous driving, but a larger set of participants and a more demanding study setup is needed to verify the impact of autonomous driving as a substitute for regular rest breaks in terms of obtaining rest.

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    fulltext
  • 28.
    Bailey-Brændgaard, Miles
    et al.
    Jönköping University, School of Health and Welfare, HHJ. Prosthetics and Orthotics.
    Enevoldsen, Peter Wibe
    Jönköping University, School of Health and Welfare, HHJ. Prosthetics and Orthotics.
    Accuracy and Reliability of 3D Scanning Spatial Data when Capturing Limb Morphology for Use within Prosthetics and Orthotics: A Scoping Review2022Independent thesis Basic level (degree of Bachelor), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Background: Scanners are becoming widespread in Prosthetics and Orthotics, replacing plaster casting in the manufacture of some types of devices. P&O shape capture must be accurate and reliable, so the device is comfortable and reproducible between clinicians/sessions.

    Objectives: To map knowledge on measuring accuracy and reliability of spatial data produced from 3D scanners.

    Methods: The study design was a scoping review using the Preferred Reporting Items for Systematic reviews and Meta-Analyses extension for Scoping Reviews (PRISMA-ScR). Studies published in or after 2010 in English with a full-text available that analyse either the accuracy/validity or reliability of human 3D scanning data within a P&O context. Sources were obtained from Pubmed, CINAHL, Scopus, Cochrane Library, Web of Science, and AMed databases on 25th March.

    Results: The search identified 115 studies of which 9 were included (7 experimental [4 prosthetic, 3 orthotic], 1 systematic review, 1 literature review). 7 analysed both reliability and accuracy/validity and 2 analysed reliability. High heterogeneity amongst studies’ methods, techniques, and equipment.

    Conclusion: Methods, techniques, and equipment used to measure accuracy/validity and reliability varied greatly though more so in the measurement of accuracy/validity. Within the studies, researchers called for more research on standardisation of measurement methods and techniques.

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    Miles and Peter Thesis
  • 29.
    Bakhtiari, Hossin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Torell, Cornelia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Teoretisk design av en multifunktionell diagnostisk enhet för mätning av vitalparametrar: Teoretisk framtagning av en lågkostnadsenhet för utvecklingsländer med fokus på Bangladesh2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [sv]

    På grund av det höga trycket på akutmottagningar räcker inte resurserna till och patienter får vänta länge på att få vård. Situationen är ännu värre i utvecklingsländer där det redan finns brist på resurser. För att handskas med detta problem behöver dagens akutmottagningar utvecklas och innovationer göras för att effektivisera användandet av resurser. Målet med detta arbete blev därför att utveckla en multifunktionell diagnostisk enhet som skulle kunna mäta flera vitalparametrar och som samtidigt var billig, kompakt, tidseffektiv och användarvänlig. För att uppnå målet analyserades vitalparametrarna kroppstemperatur, pulsfrekvens, andningsfrekvens, blodtryck och syremättnad samt deras mätmetoder. På grund av projektets begränsade resurser gjordes bedömningen att endast ett teoretiskt förslag på ett instrument som uppfyllde ovanstående krav skulle framställas.

    Analysen visade att endast pulsfrekvens, blodtryck och syremättnad kan mätas med samma instrument som fortfarande var billigt, kompakt, tidseffektivt och användarvänligt. Instrumentet som mäter dessa tre parametrar är en modifierad variant av en multivåglängds fotopletysmograf. För kroppstemperatur och andningsfrekvens föreslogs det att redan existerade billiga och användarvänliga metoder skulle användas, nämligen digital termometer respektive att observera patientens andning under en minut. Arbetet resulterade i att det togs fram figurer, flödesscheman och ett kretsschema för den multifunktionella diagnostiska enheten som skulle kunna användas för att bygga en prototyp. Därutöver evaluerades pulsoximeterns användarvänlighet då det föreslagna idén skulle vara av samma utseende som pulsoximeter. Det resulterande förslaget på diagnostisk enhet bedömdes vara till viss del anpassad för att kunna användas på akutmottagningar i Bangladesh och är anpassad för hur vården är uppbyggd där idag och dess rutiner. 

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  • 30.
    Behling, Rolf
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Astrophysics and Medical Imaging.
    Danielsson, Mats
    KTH, School of Engineering Sciences (SCI), Physics, Astrophysics and Medical Imaging.
    Particle based x-ray source2024Patent (Other (popular science, discussion, etc.))
  • 31.
    Bjällmark, Anna
    et al.
    Royal Institute of Technology, Stockholm, Sweden.
    Larsson, M
    Royal Institute of Technology, Stockholm, Sweden.
    Grishenkov, D
    Royal Institute of Technology, Stockholm, Sweden.
    Brodin, L-A
    Royal Institute of Technology, Stockholm, Sweden.
    Brismar, TB
    Karolinska University Hospital, Huddinge, Sweden.
    Paradossi, G
    Università di Roma Tor Vergata, Rome, Italy.
    Multifunctionalized microballoons for three modality contrast imaging: ultrasound, MRI and SPECT2012Conference paper (Other academic)
  • 32.
    Bleser, Gabriele
    et al.
    German Research Center for Artificial Intelligence (DFKI), Kaiserslautern, Germany.
    Steffen, Daniel
    German Research Center for Artificial Intelligence (DFKI), Kaiserslautern, Germany.
    Weber, Markus
    German Research Center for Artificial Intelligence (DFKI), Kaiserslautern, Germany.
    Hendeby, Gustaf
    Linköping University, The Institute of Technology. Linköping University, Department of Electrical Engineering, Automatic Control.
    Stricker, Didier
    German Research Center for Artificial Intelligence (DFKI), Kaiserslautern, Germany.
    Fradet, Laetitia
    Université de Technologie de Compiègne, France.
    Marin, Frédéric
    Université de Technologie de Compiègne, France.
    Ville, Nathalie
    CIC-IT Inserm 804, Rennes, France.
    Carré, Francois
    CIC-IT Inserm 804, Rennes, France.
    A personalized exercise trainer for the elderly2013In: Journal of Ambient Intelligence and Smart Environments, ISSN 1876-1364, E-ISSN 1876-1372, Vol. 5, no 6, p. 547-562Article in journal (Refereed)
    Abstract [en]

    Regular and moderate physical activity practice provides many physiological benefits. It reduces the risk of disease outcomes and is the basis for proper rehabilitation after a severe disease. Aerobic activity and strength exercises are strongly recommended in order to maintain autonomy with ageing. Balanced activity of both types is important, especially to the elderly population. Several methods have been proposed to monitor aerobic activities. However, no appropriate method is available for controlling more complex parameters of strength exercises. Within this context, the present article introduces a personalized, home-based strength exercise trainer designed for the elderly. The system guides a user at home through a personalized exercise program. Using a network of wearable sensors the user's motions are captured. These are evaluated by comparing them to prescribed exercises, taking both exercise load and technique into account. Moreover, the evaluation results are immediately translated into appropriate feedback to the user in order to assist the correct exercise execution. Besides the direct feedback, a major novelty of the system is its generic personalization by means of a supervised teach-in phase, where the program is performed once under supervision of a physical activity specialist. This teach-in phase allows the system to record and learn the correct execution of exercises for the individual user and to provide personalized monitoring. The user-driven design process, the system development and its underlying activity monitoring methodology are described. Moreover, technical evaluation results as well as results concerning the usability of the system for ageing people are presented. The latter has been assessed in a clinical study with thirty participants of 60 years or older, some of them showing usual diseases or functional limitations observed in elderly population.

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  • 33.
    Blusi, Madeleine
    et al.
    Umeå University, Faculty of Medicine, Department of Community Medicine and Rehabilitation. Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Nieves, Juan Carlos
    Umeå University, Faculty of Science and Technology, Department of Computing Science.
    Feasibility and Acceptability of Smart Augmented Reality Assisting Patients with Medication Pillbox Self-Management2019In: Studies in Health Technology and Informatics, ISSN 0926-9630, E-ISSN 1879-8365, Vol. 264, p. 521-525Article in journal (Refereed)
    Abstract [en]

    Complex prescribed medicine regimens require extensive self-management. Handling multiple pills can be confusing; using a pillbox organiser is a common strategy. A smart Medication Coach Intelligent Agent (MCIA) can support patients in handling medicine. The aim of this research was to evaluate the feasibility and acceptability of the MCIA. A prototype was tested with 15 participants, age 17-76, filled a pillbox according to prescription assisted by the MCIA implemented in a Microsoft HoloLens. A quantitative method using questionnaires was applied. Results showed that using the MCIA implemented in an AR-headset, to assist people with prescribed polypharmacy regimen in filling a pillbox, was feasible and acceptable. There was a difference related to age regarding people's willingness to use an AR-headset for medication self-management. People older than 65 felt less comfortable using the technology and were also more hesitant to use the technology than those under 65.

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  • 34.
    Boltshauser, Rasmus
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Development of a Novel Device for Optimal Sample Blood Volume Collection from Patients with Sepsis2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    When performing sepsis diagnosis, the most important preanalytical variable is blood volume. Too little blood increases the risk for false negatives whereas overfilling causes increased risk for false positives. Even though this fact is known, there are case studies showing that in a majority of tests, the taken blood sample volume is not the recommended amount. As previously tried methods have been limited in their ability to tackle the problem this study aimed at creating a technical device to aid healthcare providers with blood volume sample collection. As a base, the double diamond approach by the Design Council was used. This design approach splits up the design process in four distinctly different phases (discover, define, develop, and deliver) all using their own methods to aid the creative process.

    After completing the discover and define phase it was determined that a non-contact capacitance liquid level sensor could operate as an ideal blood volume sample device. During the development and delivery phase prototypes were created and evaluated. The final results of this work could not give conclusive evidence concerning if a non-contact liquid level sensor could operate as an ideal blood volume collection device. The methodological approach used in this thesis can be used as inspiration for a designer to create a device for a similar or different purpose. Moreover, information from this thesis can also work as reference material to develop a device to perform ideal blood volume sample collection.

    Such a device would have the potential to be an essential part of the everyday workflow in sample collection from patients with sepsis worldwide and would aid in ensures effective and fast diagnostics.

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  • 35. Borg, Johan
    et al.
    Kwee, Hoc
    Fagerberg, Gunnar
    Biomechanical aspects on the IRV mobile headrest1994In: Proceedings of the RESNA ’94 Annual Conference / [ed] M Binion, Arlington, 1994, p. 271-273Conference paper (Refereed)
  • 36.
    Borghäll, David
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Lundström, Mathilda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Utveckling av handhållen prototyp för mätning av EKG och fingerpuls2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report represents a bachelor thesis at the Royal Institute of Technology, where the goal was to create a handheld prototype. The functions of the prototype were measuring pulse in a finger using the optical sensor TCRT1010 and electrocardiogram(ECG) with bipolar limb-lead. In this thesis, the focus was put on trying to develop a user-friendly and cost-effective prototype for use in developing countries, that can be found in Africa and Asia. The reason is because there's a lack of cheap and easy to use medical equipment in those areas.

    The work was performed by developing two circuits, given by our employer, that was designed on a circuitboard and constructed by a Swedish circuitboard constructor. All components were soldered on the circuitboard and was mounted in a box with socket and batteries. The finished prototype consists of a plastic box containing one circuitboard with the function to measure either the puls of a finger or ECG, which the user can choose between using a switch. The prototype is also equipped with a removable lid, two BNC plugs for connecting an oscilloskope, one for each ciruit, three sockets for the limb lead for the ECG and finally a 4-pole socket for the optical sensor. The signals acquired are not free of noise but contains the most important parameters of the two signals for guidance if further medical diagnostic is needed.

    The prototypes final cost was 1815,5 SEK, which was not considered achieving the goal for cost-efficiency, was still believed to be useful in developing countries because of its simpel design with removable lid and easily to change batteries. It's equipped with only one switch and the compact size makes it easy to handle. The signal processing is tested to give a clear signal which enables the health professionals to identify if further diagnostics are needed. Several improvements was identified for future work, such as to reduce the cost by buying cheaper components or buying the circuitboard in greater numbers, making a wireless connection to the measuring equipment or further reducing the noise.

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  • 37.
    Bornefalk, Hans
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Grönberg, Fredrik
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Calibration of an x-ray imaging system2022Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    Disclosed is a calibration phantom for an x-ray imaging system having an x-ray source and an x-ray detector. The calibration phantom includes a combination of geometric objects of at least three different types and/or compositions including: a first object located in the middle, including a first material; a plurality of second objects arranged around the periphery of the first object, at least a subset of the second objects including a second material different than the first material, wherein the first object is relatively larger than the second objects; a plurality of third objects arranged around the periphery of the first object and/or around the periphery of at least a subset of the second objects, at least a subset of the third objects including a third material different than the first material and the second material, wherein the third objects are relatively smaller than the second objects.

  • 38.
    Bornefalk, Hans
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Grönberg, Fredrik
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Danielsson, Mats
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Enhanced spectral x-ray imaging2021Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    An x-ray imaging apparatus includes an x-ray source and detector with multiple detector elements. The source and detector are on a support that rotates around a subject, enabling projections at different view angles. The apparatus operates the x-ray source in switched kVp mode for alternately applying different voltages, including lower and higher voltages, during rotation to enable lower-energy and higher-energy exposures over the projections, providing for lower-energy projections and higher-energy projections. The x-ray detector is a photon-counting multi-bin detector allocating photon counts to multiple energy bins, and the apparatus selects counts from at least a subset of the bins to provide corresponding photon count information for both lower- and higher-energy projections. The apparatus performs material basis decomposition for some of the lower-energy projections and higher-energy projections and/or for some combinations of at least one lower-energy projection and at least one higher-energy projection, based on the corresponding photon count information.

  • 39.
    Callerström, Emma
    KTH, School of Technology and Health (STH).
    Clinicians' demands on monitoring support in an Intensive Care Unit: A pilot study, at Capio S:t Görans Hospital2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Patients treated at intensive care units (ICUs) are failing in one or several organs and requireappropriate monitoring and treatment in order to maintain a meaningful life. Today clinicians inintensive care units (ICUs) manage a large amount of data generated from monitoring devices.The monitoring parameters can either be noted down manually on a monitoring sheet or, for some parameters, transferred automatically to storage. In both cases the information is stored withthe aim to support clinicians throughout the intensive care and be easily accessible. Patient datamanagement systems (PDMSs) facilitate ICUs to retrieve and integrate data. Before managinga new configuration of patient data system, it is required that the ICU makes careful analysis ofwhat data desired to be registered. This pilot study provides knowledge of how the monitoringis performed in an Intensive Care Unit in an emergency hospital in Stockholm.The aim of this thesis project was to collect data about what the clinicians require and whatequipment they use today for monitoring. Requirement elicitation is a technique to collectrequirements. Methods used to collect data were active observations and qualitative interviews.Patterns have been found about what the assistant nurses, nurses and physicians’ require of systems supporting the clinician’s with monitoring parameters. Assistant nurses would like tobe released from tasks of taking notes manually. They also question the need for atomized datacollection since they are present observing the patient bed-side. Nurses describe a demanding burden of care and no more activities increasing that burden of care is required. Physicians require support in order to see how an intervention leads to a certain result for individual patients.The results also show that there is information about decision support but no easy way to applythem, better than the ones used today. Clinicians state that there is a need to be able to evaluatethe clinical work with the help of monitoring parameters. The results provide knowledge about which areas the clinicians needs are not supported enough by the exciting tools.To conclude results show that depending on what profession and experience the clinicians have the demands on monitoring support di↵ers. Monitoring at the ICU is performed while observing individual patients, parameters from medical devices, results from medical tests and physical examinations. Information from all these sources is considered by the clinicians and is desired to be supported accordingly before clinicians commit to action resulting in certain treatment,diagnosis and/or care.

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    Clinicains' demands on monitoring support in an ICU
  • 40. Carbonne Dit Leychert Garenne, Louis
    et al.
    Grönberg, Fredrik
    KTH, School of Engineering Sciences (SCI), Physics, Astrophysics and Medical Imaging.
    Fredenberg, Erik
    KTH, School of Engineering Sciences (SCI), Physics.
    Spectral pileup correction for photon-counting x-ray detectors2021Patent (Other (popular science, discussion, etc.))
  • 41.
    Cederström, Björn
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Refractive lens for x-rays, contains sawtooth shaped grooves for x-rays to pass through as they enter one end of lens and exit opposite end2001Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The lens contains sawtooth-shaped grooves (103, 104) located between the two ends of the lens in at least two surfaces. A refractive device for x-rays comprises a low Z-material part (101) with one end (105) for receiving x-rays from an x-ray source, and an opposite end (106) for these x-rays to exit from. The device also includes a number of essentially sawtooth-shaped grooves located between the two ends in at least two surfaces. The grooves are arranged so that x-rays entering the device will have to pass through them as they travel between the two ends of the device, after which they are focused to a refraction point. Independent claims are also included for (a) a lens containing this refractive device, (b) an x-ray system for two-dimensional focusing of x-rays and including at least two of these lenses, each x-ray beam intersecting the two lenses one after the other, and at least one lens being rotated about an optical axis relative to the other lens, (c) a method for two-dimensional focusing using these lenses, (d) a method for obtaining a bimodal energy distribution from an x-ray source using this lens, (e) a method for making a refractive x-ray lens with a sawtooth profile by engraving the profiles in a substrate, processing an original piece and using the original to press grooves into a suitable material.

  • 42.
    Cederström, Björn
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Refractive X-ray arrangement2003Patent (Other (popular science, discussion, etc.))
    Abstract [en]

    The present invention refers to a refractive arrangement for X-rays, and specially to a lens comprising: a member of low-Z material, said member of low-Z material having a first end adapted to receive x-rays emitted from an x-ray source and a second end from which emerge said x-rays received at said first end. It further comprises a plurality of substantially saw-tooth formed grooves disposed between said first and second ends, said plurality of grooves oriented such that said x-rays which are received at said first end, pass through said member of low-Z material and said plurality of grooves, and emerge from said second end, are refracted to a focal point.

  • 43.
    Cederström, Björn
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Streubuehr, Ursula
    Comparison of photon-counting to storage phosphor plate mammography using contrast-detail phantom analysis2007In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 580, no 2, p. 1101-1104Article in journal (Refereed)
    Abstract [en]

    Two digital mammography systems, one based on scanning photon counting silicon detectors and the other on storage phosphor plates (CR), have been compared in terms of image quality and dose. Sets of images of a contrast-detail phantom (CDMAM3.4) were acquired for each system and dose level. The images were evaluated in the disc diameter range 0.16-1 mm using a computer program (CDcom) and the results were fitted to a psychometric curve for each disc diameter. The contrast-detail curve was summarized into one single figure of merit, the image quality index, and the dose efficiency was calculated. The errors of the calculated parameters were assessed using statistical analysis. It was found that the scanning photon-counting system can achieve the same image quality as the storage phosphor plate (CR) system at 30-38% of the average glandular dose.

  • 44.
    Cederwall, Bo
    KTH, School of Engineering Sciences (SCI), Physics, Nuclear Physics.
    Development of a multimodality sensor for spectral photon counting CT, standard CT and PET2011In: Nuclear Instruments and Methods in Physics Research Section A: Accelerators, Spectrometers, Detectors and Associated Equipment, ISSN 0168-9002, E-ISSN 1872-9576, Vol. 648, no Suppl 1, p. S72-S74Article in journal (Refereed)
    Abstract [en]

    A prototype sensor module for multimodality medical imaging applications requiring awide intensity range has been developed. It consists of a silicon photomultiplier (SiPM)-scintillator sensor connected to a 100 kHz bandwidth current amplifier integrated with afour stage energy discriminator and a charge sensitive preamplifier. The electronics design allows for simultaneous read out of current level and discriminatory information of single photon energy or, optionally, high-resolution energy information via the charge preamplifier. This single-channel device is a proof-of-principle system designed primarily for combined spectral photon counting computed tomography (CT)/standard CT or combined with positron emission tomography (PET).

  • 45.
    Cherian, Dennis
    et al.
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Lienemann, Samuel
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Abrahamsson, Tobias
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Kim, Nara
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Berggren, Magnus
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Simon, Daniel
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Tybrandt, Klas
    Linköping University, Department of Science and Technology, Laboratory of Organic Electronics. Linköping University, Faculty of Science & Engineering.
    Soft iontronic delivery devices based on an intrinsically stretchable ion selective membrane2021In: Flexible and Printed Electronics, ISSN 2058-8585, Vol. 6, no 4, article id 044004Article in journal (Refereed)
    Abstract [en]

    Implantable electronically controlled drug delivery devices can provide precision therapeutic treatments by highly spatiotemporally controlled delivery. Iontronic delivery devices rely on the movement of ions rather than liquid, and can therefore achieve electronically controlled precision delivery in a compact setting without disturbing the microenvironment within the tissue with fluid flow. For maximum precision, the delivery device needs to be closely integrated into the tissue, which is challenging due to the mechanical mismatch between the soft tissue and the harder devices. Here we address this challenge by developing a soft and stretchable iontronic delivery device. By formulating an ink based on an in-house synthesized hyperbranched polyelectrolyte, water dispersed polyurethane, and a thickening agent, a viscous ink is developed for stencil patterning of soft ion exchange membranes (IEMs). We use this ink for developing soft and stretchable delivery devices, which are characterized both in the relaxed and stretched state. We find that their functionality is preserved up to 100% strain, with small variations in resistance due to the strain. Finally, we develop a skin patch to demonstrate the outstanding conformability of the developed device. The presented technology is attractive for future soft implantable delivery devices, and the stretchable IEMs may also find applications within wearable energy devices.

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  • 46. Clemente, Francesco
    et al.
    D'Alonzo, Marco
    Controzzi, Marco
    Edin, Benoni B.
    Umeå University, Faculty of Medicine, Department of Integrative Medical Biology (IMB), Physiology.
    Cipriani, Christian
    Non-Invasive, Temporally Discrete Feedback of Object Contact and Release Improves Grasp Control of Closed-Loop Myoelectric Transradial Prostheses2016In: IEEE transactions on neural systems and rehabilitation engineering, ISSN 1534-4320, E-ISSN 1558-0210, Vol. 24, no 12, p. 1314-1322Article in journal (Refereed)
    Abstract [en]

    Human grasping and manipulation control critically depends on tactile feedback. Without this feedback, the ability for fine control of a prosthesis is limited in upper limb amputees. Although various approaches have been investigated in the past, at present there is no commercially available device able to restore tactile feedback in upper limb amputees. Based on the Discrete Event-driven Sensory feedback Control (DESC) policy we present a device able to deliver short-lasting vibrotactile feedback to transradial amputees using commercially available myoelectric hands. The device (DESC-glove) comprises sensorized thimbles to be placed on the prosthesis digits, a battery-powered electronic board, and vibrating units embedded in an arm-cuff being transiently activated when the prosthesis makes and breaks contact with objects. The consequences of using the DESC-glove were evaluated in a longitudinal study. Five transradial amputees were equipped with the device for onemonth at home. Through a simple test proposed here for the first time-the virtual eggs test-we demonstrate the effectiveness of the device for prosthetic control in daily life conditions. In the future the device could be easily exploited as an add-on to complement myoelectric prostheses or even embedded in prosthetic sockets to enhance their control by upper limb amputees.

  • 47.
    Cruz, Javier
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Materials Science and Engineering, Microsystems Technology.
    Microfluidics for High-Pressure Inertial Focusing: Focusing, Separation and Concentration of Micro and Sub-micron Particles2020Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The birth of microsystems set the ground for technologies never imagined before, for it is not only the small size what characterizes the miniaturized systems, but unique phenomena arise in the micro scale. This thesis relates to one such unique phenomenon, inertial focusing, a phenomenon that occurs in microfluidic systems if very special conditions are met and that allows for fine manipulation of particles in fluid samples. This ability is key in a bigger picture: the analysis of complex fluids, where rare particles of interest may be present in very few numbers amongst a myriad of others, making the task difficult – if not impossible. A system exploiting inertial focusing allows, for instance, to focus, separate, isolate and concentrate such rare particles of interest, and even to transfer them to another fluid, thereby enabling/facilitating their detection and analysis. Examples of rare particles of interest in complex fluids are circulating tumor cells in blood, that give away the presence of cancer, extracellular vesicles also in blood, that contain biomarkers with physiological and pathological information about the patient, or bacteria in natural water, where the species present and their numbers are to be monitored for safety reasons and/or biological studies. This thesis covers the state of art physical principles behind the phenomenon and extends the understanding both in theory and applications. Specifically, the technology is extended to allow for manipulation of sub-micron particles, a range of interest as it comprises bacteria, viruses and organelles of eukaryotic cells. This was possible by an analysis of the balance of forces in play and by the integration of inertial focusing in high-pressure systems (up to 200 bar). In a second block, a very special line of inertial focusing is introduced and developed; inertial focusing in High Aspect Ratio Curved (HARC) microfluidics. These systems, engineered to rearrange the force field responsible for the particle manipulation, not only achieve excellent performances for focusing and concentration of particles, but also extreme resolution in their separation (mathematically unlimited; demonstrated experimentally for differences in size down to 80 nm). Perhaps more important than the performance, the systems are stable, intuitive and simpler to design, attributes that we hope will make the technology and its outstanding benefits more accessible to the community. With its remarkable performance, it would not come as a surprise if, in the near future, inertial focusing makes a strong impact on how analyses are performed nowadays and opens up for possibilities beyond the current state of the art.

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  • 48.
    Cubo, Rubén
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Systems and Control. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Automatic control.
    Mathematical modeling for optimization of Deep Brain Stimulation2016Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Deep Brain Stimulation (DBS) consists of sending mild electric stimuli to the brain via a chronically implanted lead. The therapy is used to alleviate the symptoms of different neurological diseases, such as Parkinson's Disease. However, its underlying biological mechanism is currently unknown. DBS patients undergo a lengthy trial-and-error procedure in order to tune the stimuli so that the treatment achieves maximal therapeutic benefits while limiting side effects that are often present with large stimulation values.

    The present licentiate thesis deals with mathematical modeling for DBS, extending it towards optimization. Mathematical modeling is motivated by the difficulty of obtaining in vivo measurements from the brain, especially in humans. It is expected to facilitate the optimization of the stimuli delivered to the brain and be instrumental in evaluating the performance of novel lead designs. Both topics are discussed in this thesis.

    First, an analysis of numerical accuracy is presented in order to verify the DBS models utilized in this study. Then a performance comparison between a state-of-the-art lead and a novel field-steering lead using clinical settings is provided. Afterwards, optimization schemes using intersection of volumes and electric field control are described, together with some simplification tools, in order to speed up the computations involved in the modeling.

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  • 49.
    Cubo, Rubén
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Systems and Control. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Automatic control.
    Medvedev, Alexander
    Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Division of Systems and Control. Uppsala University, Disciplinary Domain of Science and Technology, Mathematics and Computer Science, Department of Information Technology, Automatic control.
    Accuracy of the Finite Element Method in Deep Brain Stimulation Modelling2014In: Proc. International Conference on Control Applications: CCA 2014, Piscataway, NJ: IEEE , 2014, p. 1479-1484Conference paper (Refereed)
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