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  • 1.
    Aare, Magnus
    et al.
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Kleiven, Svein
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Evaluation of head response to ballistic helmet impacts, using FEM2003Conference paper (Refereed)
  • 2.
    Aare, Magnus
    et al.
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Kleiven, Svein
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Halldin, Peter
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Proposed global injury thresholds for oblique helmet impacts2003Conference paper (Refereed)
  • 3.
    Abtahi, Farhad
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems.
    Towards Heart Rate Variability Tools in P-Health: Pervasive, Preventive, Predictive and Personalized2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Heart rate variability (HRV) has received much attention lately. It has been shown that HRV can be used to monitor the autonomic nervous system and to detect autonomic dysfunction, especially vagal dysfunction. Reduced HRV is associated with several diseases and has also been suggested as a predictor of poor outcomes and sudden cardiac death. HRV is, however, not yet widely accepted as a clinical tool and is mostly used for research. Advances in neuroimmunity with an improved understanding of the link between the nervous and immune systems have opened a new potential arena for HRV applications. An example is when systemic inflammation and autoimmune disease are primarily caused by low vagal activity; it can be detected and prognosticated by reduced HRV. This thesis is the result of several technical development steps and exploratory research where HRV is applied as a prognostic diagnostic tool with preventive potential. The main objectives were 1) to develop an affordable tool for the effective analysis of HRV, 2) to study the correlation between HRV and pro-inflammatory markers and the potential degree of activity in the cholinergic anti-inflammatory pathway, and 3) to develop a biofeedback application intended for support of personal capability to increase the vagal activity as reflected in increased HRV. Written as a compilation thesis, the methodology and the results of each study are presented in each appended paper. In the thesis frame/summary chapter, a summary of each of the included papers is presented, grouped by topic and with their connections. The summary of the results shows that the developed tools may accurately register and properly analyse and potentially influence HRV through the designed biofeedback game. HRV can be used as a prognostic tool, not just in traditional healthcare with a focus on illness but also in wellness. By using these tools for the early detection of decreased HRV, prompt intervention may be possible, enabling the prevention of disease. Gamification and serious gaming is a potential platform to motivate people to follow a routine of exercise that might, through biofeedback, improve HRV and thereby health.

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    Thesis
  • 4. Abtahi, Farhad
    et al.
    Forsman, Mikael
    Diaz-Olivares, Jose A.
    KTH, School of Technology and Health (STH). KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    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

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  • 5.
    Abtahi, Farhad
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems. Karolinska Institutet, Sweden.
    Hilderman, Marie
    Bruchfeld, Annette
    Seoane, Fernando
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems. University of Borås, Sweden.
    Janerot-Sjöberg, Birgitta
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging. Karolinska Institutet, Sweden.
    Lindecrantz, Kaj
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems. Karolinska Institutet, Sweden.
    Pro-inflammatory Blood Markers and Heart Rate Variability in Apnoea as a Reflection of Basal Vagal ToneManuscript (preprint) (Other academic)
    Abstract [en]

    Pro-inflammatory cytokines play a crucial role in inflammatory response, which istightly regulated by the nervous system to avoid the damage caused by inflammation. There isevidence for a cholinergic anti-inflammatory pathway that includes afferent and efferent vagalnerves that sense the inflammation and stimulate the anti-inflammatory response. Non-functionalanti-inflammatory response might lead to excessive and chronic inflammation e.g., rheumatoidarthritis (RA), inflammatory bowel disease (IBD), and poor outcome. Heart rate variability(HRV) has been proposed as a potential tool to monitor the level of anti-inflammatory activitythrough the monitoring of vagal activity. In this paper, the association of pro-inflammatorymarkers with HRV indices is evaluated. We used a database called “Heart Biomarker Evaluationin Apnea Treatment (HeartBEAT)” that consists of 6±2 hours of Electrocardiogram (ECG)recordings during nocturnal sleep from 318 patients at baseline and 301of them at 3 monthsfollow-up. HRV indices are calculated from ECG recordings of 5-360 minutes. The results showa statistically significant correlation between heart rate (HR) and pro-inflammatory cytokines,independent of duration of ECG analysis. HRV indices e.g., standard deviation of all RRintervals (SDNN) show an inverse relation to the pro-inflammatory cytokines. Longer ECGrecordings show a higher potential to reflect the level of anti-inflammatory response. In light oftheories for the cholinergic anti-inflammatory pathway, a combination of HR and HRV as areflection of basal vagal activity might be a potential prognostic tool for interventional guidance.

  • 6.
    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.
    Löfgren, Nils
    Elimination of ECG Artefacts in Foetal EEG Using Ensemble Average Subtraction and Wavelet Denoising Methods: A Simulation2014In: XIII Mediterranean Conference on Medical and Biological Engineering and Computing 2013, Springer, 2014, p. 551-554Conference paper (Refereed)
    Abstract [en]

    Biological signals recorded from surface electrodes contain interference from other signals which are not desired and should be considered as noise. Heart activity is especially present in EEG and EMG recordings as a noise. In this work, two ECG elimination methods are implemented; ensemble average subtraction (EAS) and wavelet denoising methods. Comparison of these methods has been done by use of simulated signals achieved by adding ECG to neonates EEG. The result shows successful elimination of ECG artifacts by using both methods. In general EAS method which remove estimate of all ECG components from signal is more trustable but it is also harder for implementation due to sensitivity to noise. It is also concluded that EAS behaves like a high-pass filter while wavelet denoising method acts as low-pass filter and hence the choice of one method depends on application.

  • 7.
    Akay, Altug
    KTH, School of Technology and Health (STH), Health Systems Engineering, Systems Safety and Management.
    A Novel Method to Intelligently Mine Social Media to Assess Consumer Sentiment of Pharmaceutical Drugs2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    This thesis focuses on the development of novel data mining techniques that convert user interactions in social media networks into readable data that would benefit users, companies, and governments. The readable data can either warn of dangerous side effects of pharmaceutical drugs or improve intervention strategies. A weighted model enabled us to represent user activity in the network, that allowed us to reflect user sentiment of a pharmaceutical drug and/or service. The result is an accurate representation of user sentiment. This approach, when modified for specific diseases, drugs, and services, can enable rapid user feedback that can be converted into rapid responses from consumers to industry and government to withdraw possibly dangerous drugs and services from the market or improve said drugs and services.

    Our approach monitors social media networks in real-time, enabling government and industry to rapidly respond to consumer sentiment of pharmaceutical drugs and services.

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    fulltext
  • 8.
    Almstedt, Lisa
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Wahlin, Maja
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Digital goniometer: Ett mätverktyg för att effektivisera rehabilitering efter böjsenskada2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Between 2020 and 2021, 381 operations for flexor tendon injuries were registered in Sweden. The rehabilitation following surgery is long and requires continuous monitoring. Presently the monitoring is done through manual measurements of the patients flexing and extending capability of the fingers affected. The measurement is performed at a hand surgery department with a handheld goniometer, initially once a week. The hand surgery department at Södersjukhuset in Stockholm requested a digital tool that allows the patient to reliably measure the angles of the fingers bending and stretching capability at home instead of at the clinic. The objective of the project was therefore to create a measurement tool that measures these angles with a maximum error of 5 degrees. A measurement tool was developed where the measurement of angles takes place from an image taken by the user. The measurement tool is compatible with Android devices and can be implemented in an existing Android application. Tests showed that the measurement tool has a mean measurement error of 5 degrees or less for the proximal interphalangeal joint and the distal interphalangeal joint. In addition, the mean error was 7.3 degrees and 6.4 degrees for the metacarpophalangeal joint, bent and stretched respectively, and 10 degrees for total active motion.

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    Digital goniometer: Ett mätverktyg för att effektivisera rehabilitering efter böjsenskada
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    Mätverktygets kod
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    Filmer som används i mätverktyget
  • 9.
    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: SAE Technical Papers, ISSN 0148-7191, 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. 

  • 10.
    Ander, Simon
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Valo, Wille
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Utveckling av en mobilapplikation för rehabilitering av böjsenskador2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Flexor tendons are tendons in the fingers that are connected to the muscles in the forearm. They heal slowly after an injury and can rupture again after the repair if the patient exercises too much or lifts too heavy. Insufficient exercise can cause the tendon to adhere to surrounding tissue, resulting in finger stiffness. Rehabilitation following a flexor tendon injury typically lasts for at least three months after surgery. Therefore, patients may find it challenging to maintain motivation and follow all instructions correctly throughout this period.

    The purpose of this project was to develop a mobile application that supports patients in their rehabilitation of a flexor tendon injury along with the implementation of a digital angle measuring tool. The application was developed for both iOS and Android devices using their official integrated development environments, Android Studio and Xcode. Some features that the application consists of are a calendar providing an overview of the training plan, the ability to evaluate sessions, the ability to create custom training programs and export training data. Additionally, the application contains information about the training content, contact details, and general advice for the patient.

    Before the application can be published, it needs to be tested on patients to gather feedback on user-friendliness and functionality. The desired features from the client and the goals for the project were achieved, apart from the meeting scheduling feature, which was deprioritized. The digital angle measuring tool was implemented for Android but not for iOS. 

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    bilaga
  • 11.
    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
  • 12.
    Angelopoulos, Angelos
    et al.
    -.
    Aslanides, E.
    -.
    Backenstoss, G.
    -.
    Bargassa, P.
    -.
    Behnke, O.
    -.
    Benelli, A.
    -.
    Bertin, V.
    -.
    Blanc, F.
    -.
    Bloch, P.
    -.
    Carlson, P.
    -.
    Danielsson, Mats
    KTH, Superseded Departments (pre-2005), Physics.
    K0⇋ K̄0 transitions monitored by strong interactions: a new determination of the K L–K S mass difference2001In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 503, no 1, p. 49-57Article in journal (Refereed)
    Abstract [en]

    The CPLEAR set-up (modified) has been used to determine the KL–KS mass difference by a method where neutral-kaon strangeness oscillations are monitored through kaon strong interactions, rather than semileptonic decays, thus requiring no assumptions on CPT invariance for the decay amplitudes. The result, Δm=(0.5343±0.0063stat±0.0025syst)×1010ℏ/s, provides a valuable input for CPT tests.

  • 13.
    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.

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  • 14.
    Ashok, Joshua David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    The use of and attitudes to voice amplification in higher education institutions2020Independent thesis Advanced level (degree of Master (One Year)), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Background: Voice is still the most important tool used by teachers, but voice is varied and subject to problems. Teachers who lecture for long hours or have taught for most of their professional lives, face issues such as voice discomfort, chronic voice disorders, occupational voice disorder, stress, physiological and psychological problems. Due to issues such as poor acoustics in the classroom and absence of any installed voice amplification system, teachers might be subject to increase their vocal load to reach all the students in the classroom.

    Purpose: The aim of this study is to study the fundamental frequency (fo) and the strength Leq[dB(C)] of the teacher’s voice, with and without voice amplification system. 

    Method: Students from the preparatory year of their studies at KTH (CBH), were asked if they would like to participate in this study that researches on the voice health of teacher. Two days of teaching sessions were recorded using a microphone attached to the teacher’s mouth and three other static microphones placed in different parts of the room. The voice amplification system used in the study, was the one that was already in use at some of the classrooms at KTH. The students and the participating teacher were given questionnaires, towards the end of the teaching session to voice their opinion on the teaching voice, with and without the voice amplification system. 

    Results: The results from the data collected from the recordings, have shown that the SPL increased between 0.6 dB(C) and 5 dB(C) when the voice amplification system was turned on. The fundamental frequency (fo) of the teacher’s voice reduced by 1.4% with the use of the voice amplifier. The response of the students was overwhelmingly in support of the voice amplification system used during the recordings. 60-62% of female respondents and 68-79% of male respondents felt that the voice amplification system increased the audibility in the classroom.

    Conclusion: Leq [dB(C)] values from the mics around the classroom showed a considerable increase and thus the amplification system provides a good acoustic condition for the teacher to communicate with his students and a significant improvement in student’s comprehension of the teacher’s voice and learning conditions. There was a decrease in the fo of the teacher’s voice with the amplification, which is good for the teacher’s vocal health and reduces voice disorders while improving the quality and audibility of teacher’s voice. Majority of the students felt that the amplification system was beneficial during the teaching sessions and would like to see more amplifiers installed in more classrooms.

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    Master Thesis
  • 15.
    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.

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    Askfors 2018
  • 16.
    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.

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  • 17.
    Barsoumi, Rabi
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Odowa, Mohammed
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Utvärdering av luftrenare som använder sig av centrifugalteknologi: På uppdrag av Airission i samarbete med Karolinska Universitetssjukhuset i Huddinge2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This report presents an evaluation of a centrifugal air purifier from the company Airission used in an infectious ward at Karolinska University Hospital. Airission's air purifier removes particles and aerosols using centrifugal technology, a relatively untested technology for air purification. The goal was to investigate and attempt to verify the functionality and performance of the air purifier and compare it to a conventional air purifier that uses traditional two-stage filters for air purification.To conduct the study, a bioaerosol measuring instrument was used to measure real-time particle levels in the room. The tests were performed under different operating conditions and time intervals with the air purifier turned on and off. Data collection and analysis included calculating the mean values, comparing the particle levels between different test cases, and calculating the standard deviation.The results showed that Airission's centrifugal air purifier effectively purifies air from particles and aerosols. The purification efficiency was comparable to a conventional air purifier. It was more effective than a conventional air purifier without the use of highefficiency air filters, commonly known as HEPA filters. A significant reduction in the number of particles in the air was observed while the air purifier was in operation. However, some complications arose during the application of the HEPA filter, which could have had a negative impact on both air purifiers.In summary, the analysis demonstrates that the applied centrifugal technology in Airission's air purifier works well. The comparison with the conventional air purifier shows certain advantages of an air purifier that uses centrifugal technology - in terms of both efficiency and quality.This report contributes to the knowledge of air purification solutions to improve air quality and reduce the spread of airborne diseases, especially in hospital environments. The results can be useful for further research and development of more effective air purifiers, which in turn provide better protection for patients and hospital staff exposed to airborne pathogens.

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    Utvärdering av luftrenare som använder sig av centrifugalteknologi
  • 18.
    Belfrage, Sara
    KTH, School of Architecture and the Built Environment (ABE), Philosophy and History of Technology, Philosophy.
    Without informed consent2013In: Moral, Ethical, and Social Dilemmas in the Age of Technology: Theories and Practice, IGI Global, 2013, p. 291-305Chapter in book (Other academic)
    Abstract [en]

    The requirement of always obtaining participants' informed consent in research with human subjects cannot always be met, for a variety of reasons. This paper describes and categorises research situations where informed consent is unobtainable. Some of these kinds of situations, common in biomedicine and psychology, have been previously discussed, whereas others, for example, those more prevalent in infrastructure research, introduce new perspectives. The advancement of new technology may lead to an increase in research of these kinds. The paper also provides a review of methods intended to compensate for lack of consent, and their applicability and usefulness for the different categories of situations are discussed. The aim of this is to provide insights into one important aspect of the question of permitting research without informed consent, namely, how well that which informed consent is meant to safeguard can be achieved by other means.

  • 19.
    Bergström, Belinda
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Landström, Matilda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Automatiserad hantering av data för ökad användbarhet av ett mikro-CT-system2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    At CBH (The School of Engineering Sciences in Chemistry, Biotechnology and Health) a micro-CT has been developed, but the system has potential improvement regarding the usability. The purpose of this bachelor’s thesis was to improve the software by automatizing three aspects of manual data handling: Firstly to place the data in a folder with a name related to the obtained acquisition settings. Secondly to transfer files through SCP between the two computers connected to the micro-CT. Lastly to delete the copied data from the disk that initially saves the files.

    In order to automate the data transfer an SSH key pair with public key authentication was implemented between the two computers. To the existing software a script as well as a class controlling the three automation aspects were added. From the user interface, the class initially retrieves information about the acquisition settings to the folder name and when the acquisition is complete, the program code calls the script file that performs the SCP transfer. Afterwards a verification is made that no data was lost during the transfer, after which a deletion of the copied files is performed on the original disk. The new class improves the usability of the micro-CT and facilitates the handling of data after an acquisition.

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    Automatiserad hantering av data för ökad användbarhet av ett mikro-CT-system
  • 20.
    Bergström, Eva
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Event-based High Resolution X-ray Imaging using Compton Coincidence Detection2021Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Research on photon counting detectors (PCDs) is focused on semiconductor materials, and silicon is a strong candidate to use in PCDs for photon counting computer tomography (CT). In a silicon detector, a significant portion of the counts is due to Compton scattering events. Since only part of the incident photon energy is deposited in a Compton interaction, Compton interactions lead to a loss of spectral information. By using Compton coincidence detection, i.e., combining information from multiple Compton events caused by the same incident photon, it is possible to obtain more spectral information from Compton scattered photons, increasing the energy resolution of the detector. The goal of this thesis is to develop and evaluate a method for Compton coincidence detection for photon counting CT.

    In this thesis, a method for Compton coincidence detection based on Compton kinematics and a χ2 test is presented and compared to a previously developed method based on maximum likelihood estimation. The χ2 method utilised the connection between the energy before vs after a Compton interaction, and the scattering angle. The possible scattering angles due to deposited energy in each interaction were called the energy angles. The spatial angles between the interaction positions in the detector were calculated and compared to the energy angles through a χ2 test in order to find the correct order of interaction and the incident photon energy. The χ2 method correctly identified the interaction order of 85.8% of simulated interaction chains ending in photoelectric effect and 64.1% of simulated interaction chains containing only Compton interactions. The energy estimation was 100% correct for all chains ending in photoelectric effect, since all of the incident energy was deposited in the detector. For chains of only Comptoninteractions, the energy was estimated with an RMS error of 21.2 keV. Combining the results from chains ending in a photoelectric interaction and chains of only Comptoninteractions, the total RMS error of the energy estimation was 11.5 keV. 

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  • 21.
    Bergström, Eva
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Johansson, Ida
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Improved Spatial Resolution in Segmented Silicon Strip Detectors2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Semiconductor detectors are attracting interest for use in photon-counting spectral computed tomography. In order to obtain a high spatial resolution, it is of interest to find the photon interaction position. In this work we investigate if machine learning can be used to obtain a sub-pixel spatial resolution in a photon-counting silicon strip detector with pixels of 10 µm. Simulated charge distributions from events in one, three, and seven positions in each of three pixels were investigated using the MATLAB® Classification Learner application to determine the correct interaction position. Different machine learning models were trained and tested in order to maximize performance. With pulses originating from one and seven positions within each pixel, the model was able to find the originating pixel with an accuracy of 100% and 88.9% respectively. Further, the correct position within a pixel was found with an accuracy of 54.0% and 29.4% using three and seven positions per pixel respectively. These results show the possibility of improving the spatial resolution with machine learning.

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  • 22.
    Blom, Hans
    et al.
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Brismar, Hjalmar
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    STED microscopy: increased resolution for medical research?2014In: Journal of Internal Medicine, ISSN 0954-6820, E-ISSN 1365-2796, Vol. 276, no 6, p. 560-578Article, review/survey (Refereed)
    Abstract [en]

    Optical imaging is crucial for addressing fundamental problems in all areas of life science. With the use of confocal and two-photon fluorescence microscopy, complex dynamic structures and functions in a plethora of tissue and cell types have been visualized. However, the resolution of classical' optical imaging methods is poor due to the diffraction limit and does not allow resolution of the cellular microcosmos. On the other hand, the novel stimulated emission depletion (STED) microscopy technique, because of its targeted on/off-switching of fluorescence, is not hampered by a diffraction-limited resolution barrier. STED microscopy can therefore provide much sharper images, permitting nanoscale visualization by sequential imaging of individual-labelled biomolecules, which should allow previous findings to be reinvestigated and provide novel information. The aim of this review is to highlight promising developments in and applications of STED microscopy and their impact on unresolved issues in biomedical science.

  • 23.
    Boström, Caroline
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Messler, Olivia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Design and Evaluation of a 3D Printed Ionization Chamber2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Ionizing radiation is often used within medicine for diagnosis and treatments. Because ionizingradiation can be harmful to the body, it is important to know how it affects the tissue. Dosimetryis the study of how ionizing radiation deposits energy in a material. To measure how much ionizingradiation is deposited in the body, gas-filled detectors are often used. An ionization chamber isa type of gas-filled detector and exists in different shapes and sizes, depending on what kind ofmeasurements it is made for. Because ionization chambers are relatively expensive, it is often notpossible to buy one for each type of measurement that is to be done. This results in ionizationchambers being used for measurements they are not optimized for. This report evaluates thepossibility of 3D printing ionization chambers to make it easier to optimize them for specificmeasurements. The process included creating models of ionization chambers using CAD-software,slicing them and then 3D printing them. The 3D printed models were then brought to the SwedishRadiation Safety Authority for measurements. The ionization chambers were connected to highvoltage, and exposed to ionizing radiation in the form of high-intensity gamma-ray fields. Theoutput current of the ionization chamber was measured, which is proportional to the field intensity.The results were similar to those of a commercial ionization chamber. The conclusion is that it ispossible to 3D print ionization chambers. However, to get more accurate results, the design has tobe further optimized and more measurements need to be done.

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  • 24.
    Brolin, Karin
    et al.
    Lightness By Design AB, Stadsgarden 10,11tr, S-11645 Stockholm, Sweden..
    Lanner, Daniel
    MIPS AB, Kemistvagen 1B, S-18379 Taby, Sweden..
    Halldin, Peter
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering. MIPS AB, Kemistvagen 1B, S-18379 Taby, Sweden.
    Work-related traumatic brain injury in the construction industry in Sweden and Germany2021In: Safety Science, ISSN 0925-7535, E-ISSN 1879-1042, Vol. 136, article id 105147Article in journal (Refereed)
    Abstract [en]

    Work-related traumatic brain injuries (wrTBIs) in the construction industry have been studied in North America but, to the best of our knowledge, not in Europe. This study analyzed sets of public data on head injuries occurring in the construction industry from the workers' compensation systems in Sweden and Germany, 2014 - 2018. The ratio of wrTBI varied from 11% to 61% of all head injuries, with higher ratios for more severe injuries. The average yearly incidence (per 100,000 FTE) of wrTBI resulting in more than four days absence from work was nine in Sweden and 117 in Germany, as compared to 22-212 in North American studies. A limitation of studies based on workers' compensation claims is that they underestimate the true burden of wrTBI. The most frequent events leading to wrTBI were falls, followed by loss of control, failure of material agents, and body movements without stress. Falls from a height caused 35% of all wrTBI with more than 14 days off work in Sweden and 57% of all new injury pensions granted in Germany. In North American studies, 52-78% of the wrTBI were caused by falls. This highlights the relevance of fall safety measures to reduce wrTBI in the construction industry, such as avoiding work at heights, use of safety nets, education, and etcetera. The energy absorption of safety helmets mainly protects the head excluding face of which 49-62% were wrTBI, indicating that helmet testing standards should evaluate protection against TBI as well as skull fractures.

  • 25.
    Broomé, Michael
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Frenckner, Björn
    Broman, Mikaeö
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Recirculation during veno-venous extra-corporeal membrane oxygenation: a simulation study2015In: International Journal of Artificial Organs, ISSN 0391-3988, E-ISSN 1724-6040, Vol. 38, no 1, p. 23-30Article in journal (Refereed)
    Abstract [en]

    PURPOSE:

    Veno-venous ECMO is indicated in reversible life-threatening respiratory failure without life-threatening circulatory failure. Recirculation of oxygenated blood in the ECMO circuit decreases efficiency of patient oxygen delivery but is difficult to measure. We seek to identify and quantify some of the factors responsible for recirculation in a simulation model and compare with clinical data.

    METHODS:

    A closed-loop real-time simulation model of the cardiovascular system has been developed. ECMO is simulated with a fixed flow pump 0 to 5 l/min with various cannulation sites - 1) right atrium to inferior vena cava, 2) inferior vena cava to right atrium, and 3) superior+inferior vena cava to right atrium. Simulations are compared to data from a retrospective cohort of 11 consecutive adult veno-venous ECMO patients in our department.

    RESULTS:

    Recirculation increases with increasing ECMO-flow, decreases with increasing cardiac output, and is highly dependent on choice of cannulation sites. A more peripheral drainage site decreases recirculation substantially.

    CONCLUSIONS:

    Simulations suggest that recirculation is a significant clinical problem in veno-venous ECMO in agreement with clinical data. Due to the difficulties in measuring recirculation and interpretation of the venous oxygen saturation in the ECMO drainage blood, flow settings and cannula positioning should rather be optimized with help of arterial oxygenation parameters. Simulation may be useful in quantification and understanding of recirculation in VV-ECMO.

  • 26. Brown, Shannon
    et al.
    Ortiz-Catalan, Max
    Petersson, Joel
    Rodby, Kristian
    Seoane, Fernando
    KTH, School of Technology and Health (STH), Medical Engineering, Computer and Electronic Engineering. University of Borås, Sweden.
    Intarsia-Sensorized Band and Textrodes for Real-Time Myoelectric Pattern Recognition2016In: Proceedings of the Annual International Conference of the IEEE Engineering in Medicine and Biology Society, EMBS / [ed] Patton, J Barbieri, R Ji, J Jabbari, E Dokos, S Mukkamala, R Guiraud, D Jovanov, E Dhaher, Y Panescu, D Vangils, M Wheeler, B Dhawan, AP, Institute of Electrical and Electronics Engineers (IEEE), 2016, p. 6074-6077, article id 7592114Conference paper (Refereed)
    Abstract [en]

    Surface Electromyography (sEMG) has applications in prosthetics, diagnostics and neuromuscular rehabilitation. Self-adhesive Ag/AgCl are the electrodes preferentially used to capture sEMG in short-term studies, however their long-term application is limited. In this study we designed and evaluated a fully integrated smart textile band with electrical connecting tracks knitted with intarsia techniques and knitted textile electrodes. Real-time myoelectric pattern recognition for motor volition and signal-to-noise ratio (SNR) were used to compare its sensing performance versus the conventional Ag-AgCl electrodes. After a comprehending measurement and performance comparison of the sEMG recordings, no significant differences were found between the textile and the Ag-AgCl electrodes in SNR and prediction accuracy obtained from pattern recognition classifiers.

  • 27.
    Brunskog, Rickard
    et al.
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging. Karolinska University Hospital, MedTechLabs, BioClinicum, Solna, Sweden.
    Persson, Mats
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging. Karolinska University Hospital, MedTechLabs, BioClinicum, Solna, Sweden.
    Jin, Zihui
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging.
    Danielsson, Mats
    KTH, School of Engineering Sciences (SCI), Physics, Physics of Medical Imaging. Karolinska University Hospital, MedTechLabs, BioClinicum, Solna, Sweden.
    First experimental evaluation of a high-resolution deep silicon photon-counting sensor2024In: Journal of Medical Imaging, ISSN 2329-4302, E-ISSN 2329-4310, Vol. 11, no 1, article id 013503Article in journal (Refereed)
    Abstract [en]

    Purpose: Current photon-counting computed tomography detectors are limited to a pixel size of around 0.3 to 0.5 mm due to excessive charge sharing degrading the dose efficiency and energy resolution as the pixels become smaller. In this work, we present measurements of a prototype photon-counting detector that leverages the charge sharing to reach a theoretical sub-pixel resolution in the order of 1 μm. The goal of the study is to validate our Monte-Carlo simulation using measurements, enabling further development. Approach: We measure the channel response at the MAX IV Lab, in the DanMAX beamline, with a 35 keV photon beam, and compare the measurements with a 2D Monte Carlo simulation combined with a charge transport model. Only a few channels on the prototype are connected to keep the number of wire bonds low. Results: The measurements agree generally well with the simulations with the beam close to the electrodes but diverge as the beam is moved further away. The induced charge cloud signals also seem to increase linearly as the beam is moved away from the electrodes. Conclusions: The agreement between measurements and simulations indicates that the Monte-Carlo simulation can accurately model the channel response of the detector with the photon interactions close to the electrodes, which indicates that the unconnected electrodes introduce unwanted effects that need to be further explored. With the same Monte-Carlo simulation previously indicating a resolution of around 1 μm with similar geometry, the results are promising that an ultra-high resolution detector is not far in the future.

  • 28.
    Buchmann, Sebastian
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Enrico, Alessandro
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Holzreuter, Muriel Alexandra
    Reid, Michael S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Fibre Technology.
    Zeglio, Erica
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Niklaus, Frank
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Stemme, Göran
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Herland, Anna
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Defined neuronal-astrocytic interactions enabled with a 3D printed platformManuscript (preprint) (Other academic)
  • 29.
    Buendia, Ruben
    et al.
    University of Borås, Sweden.
    bogonez-franco, Paco
    Technical University of Catalonia.
    Nescolarde, Lexa
    Technical University of Catalonia.
    Seoane, Fernando
    KTH, School of Technology and Health (STH), Medical sensors, signals and systems (MSSS).
    Influence of electrode mismatch on Cole parameter estimation from Total Right Side Electrical Bioimpedance Spectroscopy measurements2012In: Medical Engineering and Physics, ISSN 1350-4533, E-ISSN 1873-4030, Vol. 34, no 7, p. 1024-1028Article in journal (Refereed)
    Abstract [en]

    Applications based on measurements of Electrical Bioimpedance (EBI) spectroscopy analysis, like assessment of body composition, have proliferated in the past years. Currently Body Composition Assessment (BCA) based in Bioimpedance Spectroscopy (BIS) analysis relays on an accurate estimation of the Cole parameters R-0 and R-infinity. A recent study by Bogonez-Franco et al. has proposed electrode mismatch as source of remarkable artefacts in BIS measurements. Using Total Right Side BIS measurements from the aforementioned study, this work has focused on the influence of electrode mismatch on the estimation of R-0 and R-infinity using the Non-Linear Least Square curve fitting technique on the modulus of the impedance. The results show that electrode mismatch on the voltage sensing electrodes produces an overestimation of the impedance spectrum leading to a wrong estimation of the parameters R-0 and R-infinity, and consequently obtaining values around 4% larger that the values obtained from BIS without electrode mismatch. The specific key factors behind electrode mismatch or its influence on the analysis of single and spectroscopy measurements have not been investigated yet, no compensation or correction technique is available to overcome the deviation produced on the EBI measurement. Since textile-enabled EBI applications using dry textrodes, i.e. textile electrodes with dry skin-electrode interfaces and potentially large values of electrode polarization impedance are more prone to produce electrode mismatch, the lack of a correction or compensation technique might hinder the proliferation of textile-enabled EBI applications for personalized healthcare monitoring.

  • 30.
    Byström, Matilda
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Rödlund, Sandra
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Supporting CKD Patients on Home Hemodialysis with Digital Information and Communication2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The lack of digital and easily accessible information for home hemodialysis patients leads to a disinclination of using the provided manuals. This problem could potentially be solved with a user-friendly app, where all information and communication with the healthcare providers could take place. Hence, leading to them feeling better prepared to take charge of their own treatment. The purpose of this thesis is to provide a minimum viable product of a mobile application to facilitate treatment for home hemodialysis patients. The app was developed using the programming language SwiftUI. Information was collected from patients with home hemodialysis treatment through interviews conducted in their homes. 

    The mobile application enables patients to access the manual and failure identification codes through a search bar. It also provides digital checklists, dialysis protocol and symptom follow-up. The healthcare providers can then access the dialysis protocol and symptom follow-up through remote patient monitoring. A chat function allows patients to contact nurses. The mobile application fulfills the clients’ requests and with additional work it could be fully operational. 

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  • 31.
    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
  • 32. Capece, Sabrina
    et al.
    Chiessi, Ester
    Cavalli, Roberta
    Giustetto, Pierangela
    Grishenkov, Dmitry
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Paradossi, Gaio
    A general strategy for obtaining biodegradable polymer shelled microbubbles as theranostic devices2013In: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 49, no 51, p. 5763-5765Article in journal (Refereed)
    Abstract [en]

    Fabrication of multifunctional ultrasound contrast agents (UCAs) has been recently addressed by several research groups. A versatile strategy for the synthesis of UCA precursors in the form of biodegradable vesicles with a biocompatible crosslinked polymer shell is described. Upon ultrasound irradiation, acoustic droplet vaporization transforms such particles into microbubbles behaving as UCAs. This proof of concept entails the features of a potential theranostic microdevice.

  • 33. Cecchi, N. J.
    et al.
    Domel, A. G.
    Liu, Y.
    Rice, E.
    Lu, R.
    Zhan, X.
    Zhou, Z.
    Raymond, S. J.
    Sami, S.
    Singh, H.
    Rangel, I.
    Watson, L. P.
    Kleiven, Svein
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Zeineh, M.
    Camarillo, D. B.
    Grant, G.
    Identifying Factors Associated with Head Impact Kinematics and Brain Strain in High School American Football via Instrumented Mouthguards2021In: Annals of Biomedical Engineering, ISSN 0090-6964, E-ISSN 1573-9686, Vol. 49, no 10, p. 2814-2826Article in journal (Refereed)
    Abstract [en]

    Repeated head impact exposure and concussions are common in American football. Identifying the factors associated with high magnitude impacts aids in informing sport policy changes, improvements to protective equipment, and better understanding of the brain’s response to mechanical loading. Recently, the Stanford Instrumented Mouthguard (MiG2.0) has seen several improvements in its accuracy in measuring head kinematics and its ability to correctly differentiate between true head impact events and false positives. Using this device, the present study sought to identify factors (e.g., player position, helmet model, direction of head acceleration, etc.) that are associated with head impact kinematics and brain strain in high school American football athletes. 116 athletes were monitored over a total of 888 athlete exposures. 602 total impacts were captured and verified by the MiG2.0’s validated impact detection algorithm. Peak values of linear acceleration, angular velocity, and angular acceleration were obtained from the mouthguard kinematics. The kinematics were also entered into a previously developed finite element model of the human brain to compute the 95th percentile maximum principal strain. Overall, impacts were (mean ± SD) 34.0 ± 24.3 g for peak linear acceleration, 22.2 ± 15.4 rad/s for peak angular velocity, 2979.4 ± 3030.4 rad/s2 for peak angular acceleration, and 0.262 ± 0.241 for 95th percentile maximum principal strain. Statistical analyses revealed that impacts resulting in Forward head accelerations had higher magnitudes of peak kinematics and brain strain than Lateral or Rearward impacts and that athletes in skill positions sustained impacts of greater magnitude than athletes in line positions. 95th percentile maximum principal strain was significantly lower in the observed cohort of high school football athletes than previous reports of collegiate football athletes. No differences in impact magnitude were observed in athletes with or without previous concussion history, in athletes wearing different helmet models, or in junior varsity or varsity athletes. This study presents novel information on head acceleration events and their resulting brain strain in high school American football from our advanced, validated method of measuring head kinematics via instrumented mouthguard technology.

  • 34.
    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.

  • 35.
    Chowdhury, Mishu
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Yara, Kani
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Utveckling av en mobilapplikation för schemaläggning: För sjuksköterskor och undersköterskor på närakuter2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Scheduling can be a time-consuming process; however, this can be facilitated by utilizing digital systems. In several local emergency wards in Stockholm, the scheduling of nurses and assistant nurses is still performed on paper, which results in administrative complications. The purpose of this bachelor thesis was to develop an Android mobile application that can replace the current scheduling system. The aim was to create an application that handles personnel scheduling and supports communication between the personnel.

    Using Android Studio an Android mobile application was developed that allows users to create scheduler and personnel accounts. Users with a scheduler account can create work shifts, select personnel for and remove personnel from the shift. Users with a personnel account can sign up for work shifts and receive a list of their upcoming shifts. The application provides the user with a weekly schedule which displays the created shifts and the personnel selected for the shifts. By using the application, users can communicate with each other through a chat function.

    The developed application, which meets the client's requirements, was tested and the feedback from the testing was positive. The application is still in the development stages and requires the addition of several functions to make it more customizable for the users. Future work involves developing an iOS-version and adjusting the application to utilize it in several local emergency wards. After these adjustments, the application can be distributed in Google Play and App Store.

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  • 36.
    Cloots, Rudy J.H.
    et al.
    Eindhoven University of Technology, Department of Mechanical Engineering.
    van Dommelen, J.A.W.
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Kleiven, Svein
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Geers, Marc
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Multi-scale mechanics of traumatic brain injury: predicting axonal strains from head loads2013In: Biomechanics and Modeling in Mechanobiology, ISSN 1617-7959, E-ISSN 1617-7940, Vol. 12, no 1, p. 137-150Article in journal (Refereed)
    Abstract [en]

    The length scales involved in the development of diffuse axonal injury typically range from the head level (i.e., mechanical loading) to the cellular level. The parts of the brain that are vulnerable to this type of injury are mainly the brainstem and the corpus callosum, which are regions with highly anisotropically oriented axons. Within these parts, discrete axonal injuries occur mainly where the axons have to deviate from their main course due to the presence of an inclusion. The aim of this study is to predict axonal strains as a result of a mechanical load at the macroscopic head level. For this, a multi-scale finite element approach is adopted, in which a macro-level head model and a micro-level critical volume element are coupled. The results show that the axonal strains cannot be trivially correlated to the tissue strain without taking into account the axonal orientations, which indicates that the heterogeneities at the cellular level play an important role in brain injury and reliable predictions thereof. In addition to the multi-scale approach, it is shown that a novel anisotropic equivalent strain measure can be used to assess these micro-scale effects from head-level simulations only.

  • 37.
    Cloots, Rudy J.H.
    et al.
    Eindhoven University of Technology, Department of Mechanical Engineering.
    van Dommelen, JAW
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Kleiven, Svein
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Geers, Marc
    Eindhoven University of Technology, Department of Mechanical Engineering.
    Traumatic Brain Injury at Multiple Length Scales: Relating Diffuse Axonal Injury to Discrete Axonal Impairment2010In: 2010 INTERNATIONAL IRCOBI CONFERENCE ON THE BIOMECHANICS OF INJURY PROCEEDINGS, 2010, p. 119-130Conference paper (Refereed)
  • 38.
    Courteille, Olivier
    et al.
    Department of Clinical Neuroscience, Karolinska Institutet, Stockholm, Sweden.
    Fahlstedt, Madelen
    KTH, School of Technology and Health (STH), Medical Engineering, Neuronic Engineering.
    Ho, Johnson
    KTH, School of Technology and Health (STH), Medical Engineering, Neuronic Engineering.
    Hedman, Leif
    Department of Psychology, Umeå University, Umeå, Sweden.
    Fors, Uno
    Department of Computer and Systems Sciences, Stockholm University, Stockholm, Sweden.
    von Holst, Hans
    KTH, School of Technology and Health (STH), Medical Engineering, Neuronic Engineering.
    Felländer-Tsai, Li
    Department of Clinical Science, Intervention and Technology, Division of Orthopaedics and Biotechnology, Karolin-ska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    Möller, Hans
    Department of Clinical Science, Intervention and Technology, Division of Orthopaedics and Biotechnology, Karolin-ska Institutet, Karolinska University Hospital, Huddinge, Stockholm, Sweden.
    Learning through a virtual patient vs. recorded lecture: a comparison of knowledge retention in a trauma case2018In: International Journal of Medical Education, E-ISSN 2042-6372, Vol. 9, p. 86-92Article in journal (Refereed)
    Abstract [en]

    Objectives: To compare medical students' and residents' knowledge retention of assessment, diagnosis and treatment procedures, as well as a learning experience, of patients with spinal trauma after training with either a Virtual Patient case or a video-recorded traditional lecture. Methods: A total of 170 volunteers (85 medical students and 85 residents in orthopedic surgery) were randomly allocated (stratified for student/resident and gender) to either a video-recorded standard lecture or a Virtual Patient-based training session where they interactively assessed a clinical case portraying a motorcycle accident. The knowledge retention was assessed by a test immediately following the educational intervention and repeated after a minimum of 2 months. Participants' learning experiences were evaluated with exit questionnaires. A repeated-measures analysis of variance was applied on knowledge scores. A total of 81% (n = 138) of the participants completed both tests. Results: There was a small but significant decline in first and second test results for both groups (F-(1,F-135) = 18.154, p = 0.00). However, no significant differences in short-term and long-term knowledge retention were observed between the two teaching methods. The Virtual Patient group reported higher learning experience levels in engagement, stimulation, general perception, and expectations. Conclusions: Participants' levels engagement were reported in favor of the VP format. Similar knowledge retention was achieved through either a Virtual Patient or a recorded lecture.

  • 39.
    Cuba-Gyllensten, Illapha
    et al.
    KTH, School of Technology and Health (STH). Philips Research Europe, High Tech. Campus 34, 5656AE, Eindhoven, Netherlands; ACTLab., Signal Processing Systems, TU Eindhoven, 5600MB Eindhoven, Netherlands.
    Abtahi, Farhad
    Philips Research Europe, High Tech. Campus 34, 5656AE, Eindhoven, Netherlands.
    Bonomi, Alberto Giovanni.
    KTH, School of Technology and Health (STH).
    Lindecrantz, Kaj
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems. University of Borås, Sweden.
    Seoane, Fernando
    KTH, School of Technology and Health (STH), Medical Engineering, Medical sensors, signals and systems. Karolinska Institute, Sweden.
    Amft, O.
    ACTLab., Signal Processing Systems, TU Eindhoven, 5600MB Eindhoven, Netherlands.
    Removing respiratory artefacts from transthoracic bioimpedance spectroscopy measurements2013In: XV International Conference on Electrical Bio-Impedance (ICEBI) & XIV Conference on Electrical Impedance Tomography (EIT), Institute of Physics Publishing (IOPP), 2013, Vol. 434, no 1Conference paper (Refereed)
    Abstract [en]

    Transthoracic impedance spectroscopy (TIS) measurements from wearable textile electrodes provide a tool to remotely and non-invasively monitor patient health. However, breathing and cardiac processes inevitably affect TIS measurements, since they are sensitive to changes in geometry and air or fluid volumes in the thorax. This study aimed at investigating the effect of respiration on Cole parameters extracted from TIS measurements and developing a method to suppress artifacts. TIS data were collected from 10 participants at 16 frequencies (range: 10 kHz - 1 MHz) using a textile electrode system (Philips Technologie Gmbh). Simultaneously, breathing volumes and frequency were logged using an electronic spirometer augmented with data from a breathing belt. The effect of respiration on TIS measurements was studied at paced (10 and 16 bpm) deep and shallow breathing. These measurements were repeated for each subject in three different postures (lying down, reclining and sitting). Cole parameter estimation was improved by assessing the tidal expiration point thus removing breathing artifacts. This leads to lower intra-subject variability between sessions and a need for less measurements points to accurately assess the spectra. Future work should explore algorithmic artifacts compensation models using breathing and posture or patient contextual information to improve ambulatory transthoracic impedance measurements.

  • 40.
    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.

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  • 41. Deck, C.
    et al.
    Bourdet, N.
    Halldin, Peter
    KTH, School of Technology and Health (STH), Medical Engineering, Neuronic Engineering.
    DeBruyne, G.
    Willinger, R.
    Protection capability of bicycle helmets under oblique impact assessed with two separate brain FE models2017In: Conference proceedings International Research Council on the Biomechanics of Injury, IRCOBI, International Research Council on the Biomechanics of Injury , 2017, p. 190-200Conference paper (Refereed)
    Abstract [en]

    The present study proposes a bicycle helmet evaluation under oblique impact based on a coupled experimental versus numerical test method using two separate brain FE models. For each of the 17 helmet types three oblique impacts have been conducted and the 6D headform acceleration curves have been considered as the initial conditions of the brain injury risk assessment based on the FE simulation. The study gives a new insight into helmet protection capability under oblique loading and shows that adequate protection is offered by most of the helmets when impacts leading to rotation around X and Y are concerned. However when impact leads to rotation around Z axis the protection is critical for nearly all helmets. The study considers two separate brain FE models for the assessment of brain injury risk and thus permits a comparative analysis of brain FE modeling. When impact induces rotation around X and Y axis the computed results are comparable. However when rotation around Z axis are concerned significant differences are observed which demonstrate that further efforts are needed in the domain of model based brain injury criteria harmonization. 

  • 42.
    Dizdarevic, Sven
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Hämäläinen, Anton
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Developing a simulation model for decision making in a further digitized Swedish healthcare system2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Owing to computer simulations, healthcare managers-and decision makers are more capable than ever to understand and evaluate the consequences of their decisions. In 2016, the Swedish government put forward ”Vision eHealth 2025”, emphasizing the importance of digitization within the healthcare system. This thesis aimed at studying the current demands regarding eHealth in Sweden, and what simulation architecture is capable of accurately simulating a digitized Swedish healthcare system. An extensive literature study was conducted, followed by an implementation phase, and finally a validation procedure. It was first concluded that the following three areas of eHealth applications would greatly benefit Swedish healthcare: a fully integrated journal system, systems for care consultations over the internet, and systems for tele-monitoring of chronics and the elderly. The fidelity of a provided first version of a simulation architecture was then examined, and potential areas for improvement were identified. The implementation phase subsequently included changes to the following aspects of the provided simulation platform: level of generality, the patient agent class (pHome), healthcare resources, illness dynamics & levels of care, workflow chart logic, optimization criteria, user-interface, and output variables. The validation procedure consisted of four interviews with professionals knowledgeable about the Swedish healthcare system, for which the developed simulation architecture was demonstrated. It was concluded that, while the level of detail required for a simulation platform to accurately model the consequences of decision making in a digitized Swedish healthcare system is not known, the developed simulation platform is currently not satisfactory. Above all, it lacks specificity in the output variables.

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  • 43.
    Dånmark, Staffan
    et al.
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Gladnikoff, Micha
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Frisk, Thomas
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Zelenina, Marina
    KTH, School of Engineering Sciences (SCI), Applied Physics, Cell Physics.
    Mustafa, Kamal
    Russom, Aman
    KTH, School of Engineering Sciences (SCI), Applied Physics.
    Finne-Wistrand, Anna
    KTH, School of Chemical Science and Engineering (CHE), Fibre and Polymer Technology, Polymer Technology.
    Development of a novel microfluidic device for long-term in situ monitoring of live cells in 3-dimensional matrices2012In: Biomedical microdevices (Print), ISSN 1387-2176, E-ISSN 1572-8781, Vol. 14, no 5, p. 885-893Article in journal (Refereed)
    Abstract [en]

    Using the latest innovations in microfabrication technology, 3-dimensional microfluidic cell culture systems have been developed as an attractive alternative to traditional 2-dimensional culturing systems as a model for long-term microscale cell-based research. Most microfluidic systems are based on the embedding of cells in hydrogels. However, physiologically realistic conditions based on hydrogels are difficult to obtain and the systems are often too complicated. We have developed a microfluidic cell culture device that incorporates a biodegradable rigid 3D polymer scaffold using standard soft lithography methods. The device permits repeated high-resolution fluorescent imaging of live cell populations within the matrix over a 4 week period. It was also possible to track cell development at the same spatial location throughout this time. In addition, human primary periodontal ligament cells were induced to produce quantifiable calcium deposits within the system. This simple and versatile device should be readily applicable for cell-based studies that require long-term culture and high-resolution bioimaging.

  • 44.
    Eiderbäck, Jesper
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Jahnke, Felix
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    A New Approach for Positioning Human Body Models Utilising the 3D-Graphics Program Blender2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A finite element human body model (FE HBM) is a detailed virtual model of the human body that, for example, is used for simulating traffic accidents. A problem with HBMs is that there is no simple way to position the HBMs in non-standard positions. As different postures during an impact will affect the body in different ways it is vital to have the ability to position the HBMs. In this project it was investigated if it is possible to position a HBM from THUMS, by first positioning only the skin and skeleton, as control points, in the 3D-graphics program Blender. Thereafter a radial basis function interpolation is utilised to morph the rest of the HBM into the new position. The results indicate that in theory, it is possible to position a HBM using a 3D-graphics software. However, the method developed in this project resulted in a disfigurement of the morphed model. The disfigurement is possibly due to the change in distance between the skin and skeleton when positioning those body parts in Blender. 

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  • 45.
    Eivinsson, Tova
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Saleh, Mariam
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Googles röstgränssnitts lämplighet för användning i en röstbaserad medicinteknisk tjänst2022Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In this project, the Google Speech API has been evaluated based on the purpose of creating a program that will identify a person based on their voice. This project is done together with a company called Call Knut whose goal is to design a service based on AI technology that will call the elderly. Since the service is aimed at the elderly, Call Knut wants a program that can identify the elderly based on their voice. 

    An application was created using the Google Speech API to transcribe and distinguish two voices in an audio file. Then audio files were collected from different people in a wide age range and audio files were combined. The combined audio files were then analyzed to verify whether the Google Cloud interface is optimal for the purpose. In 29.2 % of the combined audio files Google Speech API managed to both distinguish two voices and transcribe what they said. In total, Google Speech API failed with 70.8 % of the entries. 

    Our conclusion was that Google's voice interface is not suitable to use to develop Call Knut’s planned service where voice recognition must work with high precision. Further development work is recommended to focus on testing other programs or voice interfaces. 

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  • 46.
    Ekelund, Emil
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Fogelberg Skoglösa, David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Geant4 Simulations of Hadron Therapy and Refinement of User Interface2019Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Radiotherapy is one of the most used methods for treating cancer and the most common way to execute such treatments is to irradiate tumors with high energy photons. This can damage healthy tissue along the irradiation line. By using hadron therapy and instead irradiate the tumor with charged particles (protons or Carbon 12 ions), the energy can be concentrated to a more specific place in the body. However, the method is not well studied and the tools available for simulating hadron therapy can be hard to use.

    When simulating hadron therapy and other nuclear interactions a large amount of calculations need to be executed. Monte Carlo methods is a numerical method to solve equations based on repeated number sampling and is used in the simulation program Geant4. Hadron therapy was simulated with Geant4 and the data was analyzed with the data analysis framework ROOT. New macros and analysis scripts were created with the intention to help new Geant4 users. The aim to make Geant4 easier to use was partially met. The implementation of code for the low energy region of Carbon 12 projectiles was unsuccessful.

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  • 47.
    El Borgi, Mouna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Norman, Mårten
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Estimation of Velocities in Ice Hockey Collisions2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Concussions occur frequently as a result of tackles in ice hockey. Analysis of video material may provide an understanding of the relationship between the kinematics of collisions and the risk for injury. In this thesis, two video analysis methods were used to estimate the impact velocities of 22 ice hockey tackles that resulted in concussions. The Point tracking method uses tracking of user-defined object points on the players and ice to estimate the velocities. It was used in an earlier thesis. A deep learning-based method was implemented in this thesis. It uses a pre-trained deep learning model to detect the players in each frame of the video. Both methods were validated in this thesis using soccer videos containing accelerometer data from the players. The mean error was 25.6 % for the Point tracking method and 43.1 % for the Deep learning method. The difference was not significant. Both methods calculate the player velocity as a mean from a given number of video frames before impact. The choice of the number of frames did not significantly affect the difference in estimated velocities between the Point tracking method and the Deep learning method. The Point tracking method succeeded in estimating velocities in 17 cases. The mean velocities for the attacking and injured players were 10.5 m/s and 9.3 m/s, respectively. The Deep learning method succeeded in 9 cases, and the mean velocities were 9.7 m/s and 9.5 m/s. The velocities are higher than what has been found in earlier research, suggesting that both methods may be biased towards estimating too high velocities. More investigation needs to be done to evaluate the methods’ performance, possibly by comparing with accelerometer data from ice hockey.

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  • 48.
    Elksne, Anna
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Zidan, Dima
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Placering av patienter på akutmottagningen på Södersjukhuset: Utveckling av en webbapplikation2021Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The triage nurses that are responsible for the placement of patients at Södersjukhuset’s emergency department in Stockholm, Sweden, use the digital medical record system TakeCare. TakeCare is a renowned record system that has been used in Region Stockholm since 2013. However, the nurses using the system experience some difficulty, especially when it comes to the user interface when placing new patients. The current system lacks a clear overview of the emergency departments' many modules and healthcare teams, which makes it difficult to make decisions regarding the placement of incoming patients. The nurses are therefore forced to go through each module one by one to see the current strain in each team. A prototype for a decision-supporting web application with a clear overview of each module could potentially be integrated into the current medical record system and thus facilitate an easier placement process. A web application was made in this study and can eventually be used by the health care staff after further development. This report proves that there is potential for improvement for the current system and that a decision-making tool would improve the flow in the ED. 

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  • 49.
    Enrico, Alessandro
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Bright Lights: Innovative Micro- and Nano-Patterning for Sensing and Tissue Engineering2022Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Light is the primary source of energy on our planet and has been a significant driver in the evolution of human society and technology. Light finds applications in two-dimensional (2D) photolithography and three-dimensional (3D) printing, where a pattern is transferred to a material of interest by ultraviolet (UV) light exposure, and in laser scribing and cutting, where high power lasers are used to pattern the surface of objects or cut through the bulk of the material of interest. However, conventional light-based processing has three main constraints: a) the wavelength of visible light limits resolution, b) only materials that absorb the wavelength in use can be efficiently processed, and c) intense laser light burns its target, degrading the material surrounding the exposed areas and further limiting material compatibility. Overcoming these limitations is the core of this thesis.

    The first part of this thesis describes three different patterning methods enabled by intelligent design and non-linear light-matter interaction. The first work reports the use of light at 365 nm to generate sub-20 nm wide nanowires (NWs) exploiting crack lithography, exceeding the possible resolution given by diffraction limit by 10-fold. The second work describes how the non-linear interaction of femtosecond laser pulses with otherwise transparent glass enables nanostructuring of borosilicate coverslips. Positively charging the nanostructured glass surfaces grants a “attract and destroy” bactericidal functionality and maintains the transparency of the substrate, creating a microscopy compatible platform to study bacteria-surface interactions and providing strategies to fight antibiotic-resistant bacteria. The third and fourth works show how femtosecond lasers can directly pattern carbon nanotube films and 2D materials (graphene, molybdenum disulfide, and platinum diselenide) without damaging the substrate or the material surrounding the exposed area. Non-linear interaction with high-energy laser pulses allows sub-300 nm resolution, circumventing the limit given by light diffraction in the linear regime. The combination of high resolution, femtosecond exposure, and ultrafast scanning speed provides a valid alternative to resist-based photolithography while eliminating the related contamination issues for these sensitive materials.

    The second part of this thesis describes two different 3D micromachining approaches enabled by high-intensity laser light. The fifth work presents a collagen patterning method based on laser-induced cavitation, called cavitation molding. This method represents a new biomanufacturing mode that is neither additive nor subtractive. In this study, cavitation molding enables the generation of a micro vascularized cancer-on-chip model, consisting of an in-vivo-like spheroidal mass of cancer cells surrounded by artificial blood vessels. In the sixth and final work, we used two-photon polymerization to generate 3D platforms in a biocompatible resin. This platform enables the study of the physiology of neurons and their interaction with astrocyte cells. The low autofluorescence of the printed resins allows optical readout of the neuronal activity by calcium imaging.

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  • 50.
    Enrico, Alessandro
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Voulgaris, Dimitrios
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Östmans, Rebecca
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Sundaravadivel, Naveen
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Moutaux, Lucille
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Cordier, Aurélie
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Niklaus, Frank
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Herland, Anna
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    Stemme, Göran
    KTH, School of Electrical Engineering and Computer Science (EECS), Intelligent systems, Micro and Nanosystems.
    3D Microvascularized Tissue Models by Laser-Based Cavitation Molding of Collagen2022In: Advanced Materials, ISSN 0935-9648, E-ISSN 1521-4095, Vol. 34, no 11Article in journal (Refereed)
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