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  • 1.
    Abaid, Mohammed Abderhman
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Validation of a new iPhone application for measurements of wrist velocity during actual work tasks2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The breakthrough in mobile technology and the development of smartphones, supplied with sensing devices such as Inertial Measurement Units (IMUs), has made it possible to obtain accurate and reliable data on the angular velocity for different objects. The available technical sensors for wrist movements, such as electrogoniometers, are costly, time-consuming, and need a particular computer program to be analyzed. Therefore, there is a need to develop user-friendly risk assessment methods for wrist angular velocity measurements. This master thesis aimed to validate the accuracy of a newly developed iPhone application (App), "ErgoHandMeter," for wrist velocity in actual work tasks, by comparing the “ErgoHandMeter” to standard electrogoniometers. The project study was performed with four participants, two females and two males, from three jobs performing actual work tasks. The total angular velocity obtained by the mobile application was compared with the angular velocity data from the standard electrogoniometer. The total angular velocities obtained from the smartphone and the goniometer were computed at the 10th, 50th and 90th percentile for the four subjects. The 50th percentile of goniometer-flexion velocity (G-flex) was 7.4 ± 5.4°/s, for the goniometer-total (G-tot) 8.7 ± 6.5)°/s and for App 7.2 ± 4.9°/s. The correlation coefficient for the 50th percentile of goniometer-flexion (G-flex) parameter and smartphone application was 0.994. For the goniometer-total (G-tot) and the application, it was 0.993. In a Bland-Altman plot the mean difference between G-flex and App for the 50th percentile was -0.18 °/s and for G-tot and App was -1.54 °/s, i.e. the App was lower in average. The limit of the agreement between G-Flex and App, and G-tot and App stayed within two standard deviations. For G-Flex and App (mean+1.96SD) was 1.34 °/s, (mean-1.96SD) was -1.71 °/s, while for G-tot and App (mean+1.96SD) was 1.89 °/s, (mean-1.96SD) was -4.96 °/s, indicating an adequate agreement between the two methods. A limitation was that the included occupations were all relatively low velocity. However, in conclusion, the results indicate that the two methods agree adequately and can be used interchangeably.

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  • 2.
    Abbasiasl, Taher
    et al.
    Sabanci University.
    Niazi, Soroush
    Sabanci University.
    Sheibani Aghdam, Araz
    Sabanci University.
    Chen, Hongjian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Cebeci, Fevzi Cakmak
    Sabanci University.
    Ghorbani, Morteza
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging. 1 Sabanci University Nanote.
    Grishenkov, Dmitry
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Kosar, Ali
    Sabanci University.
    Effect of intensified cavitation using poly (vinyl alcohol) microbubbles on spray atomization characteristics in microscale2020In: AIP Advances, E-ISSN 2158-3226, Vol. 10, no 2Article in journal (Refereed)
    Abstract [en]

    In this study, cavitating flows inside a transparent cylindrical nozzle with an inner diameter of 0.9 mm were visualized, and the effect of cavitation on atomization characteristics of emerging sprays was investigated. Different patterns of cavitating flows inside the nozzle were visualized using a high-speed camera. In-house codes were developed to process the captured images to study the droplet size distribution and droplet velocity in different flow regimes. The results show that cavitating flows at the microscale have significant effects on atomization characteristics of the spray. Two working fluids, namely, water and poly(vinyl alcohol) microbubble (PVA MB) suspension, were employed. Accordingly, the injection pressures were detected as 690 kPa, 1035 kPa, and 1725 kPa for cavitation inception, supercavitation, and hydraulic flip flow regimes in the case of water, respectively. The corresponding pressures for the aforementioned patterns for PVA MB suspension were 590 kPa, 760 kPa, and 1070 kPa, respectively. At the microscale, as a result of a higher volume fraction of cavitation bubbles inside the nozzle, there is no large difference between the cavitation numbers corresponding to cavitating and hydraulic flip flows. Although the percentage of droplets with diameters smaller than 200 μm was roughly the same for both cases of water and PVA MB suspension, the Sauter mean diameter was considerably lower in the case of PVA MBs. Moreover, higher droplet velocities were achieved in the case of PVA MBs at lower injection pressures.

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  • 3.
    Abbasiasl, Taher
    et al.
    Sabanci Univ, Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey.;Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey..
    Sutova, Hande
    Sabanci Univ, Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey.;Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey..
    Niazi, Soroush
    Sabanci Univ, Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey.;Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey..
    Celebi, Gizem
    Sabanci Univ, Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey.;Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey..
    Karavelioglu, Zeynep
    Yildiz Tech Univ, Dept Bioengn, Istanbul, Turkey..
    Kirabali, Ufuk
    Yildiz Tech Univ, Dept Mechatron Engn, Istanbul, Turkey..
    Yilmaz, Abdurrahim
    Yildiz Tech Univ, Dept Mechatron Engn, Istanbul, Turkey..
    Uvet, Huseyin
    Yildiz Tech Univ, Dept Mechatron Engn, Istanbul, Turkey..
    Kutlu, Ozlem
    Sabanci Univ, Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey.;Sabanci Univ, Ctr Excellence Funct Surfaces & Interfaces Nanodi, TR-34956 Istanbul, Turkey..
    Ekici, Sinan
    Sabanci Univ, Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey..
    Ghorbani, Morteza
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging. Sabanci Univ, Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey.;Sabanci Univ, Ctr Excellence Funct Surfaces & Interfaces Nanodi, TR-34956 Istanbul, Turkey..
    Kosar, Ali
    Sabanci Univ, Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey.;Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey.;Sabanci Univ, Ctr Excellence Funct Surfaces & Interfaces Nanodi, TR-34956 Istanbul, Turkey..
    A Flexible Cystoscope Based on Hydrodynamic Cavitation for Tumor Tissue Ablation2022In: IEEE Transactions on Biomedical Engineering, ISSN 0018-9294, E-ISSN 1558-2531, Vol. 69, no 1, p. 513-524Article in journal (Refereed)
    Abstract [en]

    Objective: Hydrodynamic cavitation is characterized by the formation of bubbles inside a flow due to local reduction of pressure below the saturation vapor pressure. The resulting growth and violent collapse of bubbles lead to a huge amount of released energy. This energy can be implemented in different fields such as heat transfer enhancement, wastewater treatment and chemical reactions. In this study, a cystoscope based on small scale hydrodynamic cavitation was designed and fabricated to exploit the destructive energy of cavitation bubbles for treatment of tumor tissues. The developed device is equipped with a control system, which regulates the movement of the cystoscope in different directions. According to our experiments, the fabricated cystoscope was able to locate the target and expose cavitating flow to the target continuously and accurately. The designed cavitation probe embedded into the cystoscope caused a significant damage to prostate cancer and bladder cancer tissues within less than 15 minutes. The results of our experiments showed that the cavitation probe could be easily coupled with endoscopic devices because of its small diameter. We successfully integrated a biomedical camera, a suction tube, tendon cables, and the cavitation probe into a 6.7 mm diameter cystoscope, which could be controlled smoothly and accurately via a control system. The developed device is considered as a mechanical ablation therapy, can be a solid alternative for minimally invasive tissue ablation methods such as radiofrequency (RF) and laser ablation, and could have lower side effects compared to ultrasound therapy and cryoablation.

  • 4.
    Abd Alwaheb, Sofia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Implementering DevSecOps metodik vid systemutveckling för hälso och sjukvård2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    In healthcare, IT security is crucial for protecting both personal information and patient safety. Currently, the implementation of security measures and testing is done after software development, which can reduce efficiency, and pose a potential risk to patient privacy. This study examined the implementation of the DevSecOps methodology in healthcare, focusing on the development phase. By interviewing employees and using security tools such as SAST, code review, penetration testing, and DAST, benefits and challenges were identified. The challenges included a lack of security knowledge and difficulty integrating tools for free. Despite this, the results demonstrated the potential to enhance security, streamline operations, and save money by utilizing free tools and implementing security during the development phase. Training and hiring security-competent personnel were also emphasized as important for maintaining high security standards.

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  • 5.
    Abdalla, Osman
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Design and implementation of a signaling system for a novel light-baseed bioprinter: Design och implementering av ett signalsystem för en ny ljusbaserad bioprinter2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    A 3D bioprinter employing light-based technology has been designed and constructed in an EU-funded research initiative known as BRIGHTER (Bioprinting by Light-Sheet Lithography). This initiative is a collaborative effort between institutions and companies and aims to develop a technique for efficient and accurate production of engineered tissue.

    Presently, the bioprinter’s function is limited to 2D printing, with the lack of 3D printing capabilities. 

    The problem addressed is the integration of two separate electronic systems within the bioprinter to control the laser beam’s trajectory for 3D printing. The goal of the project is to create functional software and simulation tools to control the hardware modules in a precise and synchronized manner, thereby enabling 3D printing.

    The outcome manifests as a software prototype, which successfully facilitates intercommunication between the two electronic subsystems within the bioprinter, thereby enabling further progress on the bioprinter with 3D printing available. Nevertheless, the prototype requires thorough testing to determine its optimal operational efficiency in terms of timing the movements for the various hardware modules.

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    Bioprinter
  • 6.
    Abdi Dahir, Najiib
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Dahir Ali, Ikran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Privacy preserving data access mechanism for health data2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Due to the rise of digitalization and the growing amount of data, ensuring the integrity and security of patient data has become increasingly vital within the healthcare industry, which has traditionally managed substantial quantities of sensitive patient and personal information. This bachelor's thesis focused on designing and implementing a secure data sharing infrastructure to protect the integrity and confidentiality of patient data. Synthetic data was used to enable access for researchers and students in regulated environments without compromising patient privacy. The project successfully achieved its goals by evaluating different privacy-preserving mechanisms and developing a machine learning-based application to demonstrate the functionality of the secure data sharing infrastructure. Despite some challenges, the chosen algorithms showed promising results in terms of privacy preservation and statistical similarity. Ultimately, the use of synthetic data can promote fair decision-making processes and contribute to secure data sharing practices in the healthcare industry.

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    Examensarbete
  • 7.
    Abdirahman, Khalid
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Förnberg, Sebastian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Styrsystem för solcellsladdade batterier2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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    Styrsystem för solcellsladdade batterier
  • 8.
    Abduljabar, Haya
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Hadi, Hanan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Sterilization of Medical Equipment in a Third World Country: A Minor Field Study in Linga Linga, Mozambique2020Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The non-profit organization Project Vita has recently built a maternity clinic in Linga Linga, where the medical instruments to be sterilized are boiled in water for an hour. The fuel needed to boil the water is wood, which is a scarce resource. This is why, according to the healthcare worker that was interviewed in Mozambique, it is desirable to have an electric-powered solution to sterilise the medical instruments.

    After research on the different sterilization techniques that exist, the conclusion was drawn that the safest way to sterilise is by the use of an autoclave. However, it would be difficult to implement and maintain an autoclave in Linga Linga. Therefore, it was proposed to build an autoclave using a pressure cooker. Through experimentation, different programs, times and pressures were tested to find out if a pressure cooker could sterilise a common object. It could be concluded that theoretically, it seems that the pressure cooker reached a temperature of over 121 degrees Celsius. However, the pressure could not be measured nor was a biological indicator, that could indicate if an autoclave or pressure cooker does sterile, used. 

    This project was to be done in Mozambique, but because of COVID-19, a travel ban was set in motion and universities and laboratories had limited access, thus limiting the project. As a result, it is still unclear if a pressure cooker can be used to sterilize medical instruments.

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  • 9.
    Abdulnoor, John
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Gawriyeh, Ramy
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    A study of methods to synchronize different sensors between two smartphones2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Obtaining data simultaneously from different sensors located on different mobile devices can be useful for applications such as sports and medicine. In order for the data from the different sensors to be combined for analysis, the mobile devices need to be time synchronized first. This paper presents an application that can be used to calculate the difference between the internal clocks of two android devices using a combination of the Cristian and Marzullo algorithms. Different methods to connect the devices over Wi-Fi as well as the internet are tested to determine the optimal method for clock synchronization. The paper also validates the synchronization by testing different sensors on two identical android smartphones. The results show that clock synchronization between two mobile devices can be achieved with a round-trip time of 2 milliseconds or less using Wi-Fi Direct. Validation of the synchronization shows that a delay of 7 milliseconds or less can be achieved between two sensors of the same type on two identical android smartphones. It also shows that the least achievable delay between sensors of different types is 16 milliseconds. The conclusion is that once two android smartphones’ clocks are synchronized, only data from sensors of the same type can be combined, with the exception of the camera sensor. Further testing with more robust equipment is needed in order to eliminate human error which could possibly yield more desirable results.

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  • 10.
    Abourraja, Mohamed Nezar
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Kringos, Nicole
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Meijer, Sebastiaan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Exploiting simulation model potential in investigating handling capacity of Ro-Ro terminals: The case study of Norvik seaport2022In: Simulation Modelling Practice and Theory, ISSN 1569-190X, Vol. 117, p. 102513-102513, article id 102513Article in journal (Refereed)
    Abstract [en]

    In this paper, the spotlight is directed towards studying the handling capacity of pure Ro-Ro terminals, especially the new terminal of Norvik port. To this end, a simulation model based on a distributed architecture is built to assess the handling capacity under different flow scenarios with a particular focus on the trailer flow and export-lorry flow the terminal can handle in terms of resource availability, trailer-dwell times and management rules. This helped to determine the number of resources required to evacuate smoothly the incoming flows and to identify where potential bottlenecks happen the most inside the terminal. The established model is verified then validated by experts to conduct properly the experiment study where the model is fed with empirical data provided by terminal authorities. This experiment showed that the terminal can handle flows of which trailers do not exceed 17% and the export fraction of lorries is at most 42%.

  • 11.
    Abourraja, Mohamed Nezar
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Kringos, Nicole
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges.
    Meijer, Sebastiaan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Proposal of a module-driven architecture for building simulation models devoted to container terminals: dilemmas in applying generic, flexible, and modular principles2023In: Simulation (San Diego, Calif.), ISSN 0037-5497, E-ISSN 1741-3133, Vol. 99, no 7, p. 703-727Article in journal (Refereed)
    Abstract [en]

    Container terminals are complex systems where containerized cargo undergoes a set of processing and handling operations to be delivered to their outgoing modes. A pool of decision support methods and simulation models has been developed to assist planners and managers in making decisions about daily operations. Nevertheless, most are designed for a particular terminal and not generic types. Indeed, a generic model serves as a conceptual factory to create specific models which greatly reduces the time and efforts of development; however, building such a model is no mean feat. To this aim, the paper on hand discusses the complexity of applying genericity, flexibility, and modularity in system modeling and proposes a generic architecture to build modular and flexible simulation models for container terminals. This architecture is split into a set of smaller, manageable, well-connected, and generic modules that facilitate the creation of highly parametrized specific models. An illustrative example of the architecture usage is presented in a case study, the new container terminal of Stockholm, and the resulting models were validated by subject matter experts. Finally, to prove its efficiency, a numerical study fed with real data is conducted to investigate the handling capacity of the studied system under different handling and flow scenarios. The obtained results show that the terminal handling capacity can be increased by around 50% if three to four more straddle carriers are added to the existing fleet.

  • 12.
    Abourraja, Mohamed Nezar
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Marzano, Luca
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Raghothama, Jayanth
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Boodaghian Asl, Arsineh
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Darwich, Adam S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Meijer, Sebastiaan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Lethvall, Sven
    Uppsala University Hospital,Uppsala,Sweden.
    Falk, Nina
    Uppsala University Hospital,Uppsala,Sweden.
    A Data-Driven Discrete Event Simulation Model to Improve Emergency Department Logistics2022In: Proceedings of the 2022 Winter Simulation Conference, Institute of Electrical and Electronics Engineers (IEEE) , 2022Conference paper (Refereed)
    Abstract [en]

    Demands for health care are becoming overwhelming for healthcare systems around the world regarding theavailability of resources, particularly, in emergency departments (EDs) that are continuously open and mustserve immediately any patient who comes in. Efficient management of EDs and their resources is requiredmore than ever. This could be achieved either by optimizing resource utilization or by the improvement ofhospital layout. This paper investigates, through data-driven simulation alternative designs of workflowsand layouts to operate the ED of the Uppsala University Hospital in Sweden. Results are analyzed tounderstand the requirements across the hospital for reduced waiting times in the ED. The main observationrevealed that introducing a new ward dedicated to patients having complex diagnoses with a capacity ofless than 20 beds leads to lower waiting times. Furthermore, the use of data-mining was of great help inreducing the efforts of building the simulation model.

  • 13.
    Abourraja, Mohamed Nezar
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Meijer, Sebastiaan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Boukachour, Jaouad
    Normandie University, UNIHAVRE, 76600 Le Havre, France.
    A model-driven design approach for Ro-Ro and container terminals: from requirements analysis down to simulation model implementation2021In: 20th International Conference on Modeling and Applied Simulation, MAS 2021, Cal-Tek Srl , 2021, p. 9-20Conference paper (Refereed)
    Abstract [en]

    Modeling, one of the main pillars of good scientific research, is a long-standing multidisciplinary activity to understand and analyze complex systems. In this paper, the focus is directed toward conceptual modeling of multi-terminal seaports specialized in handling and treatment of intermodal transport units (ITU). These systems are complex with highly dynamic and stochastic behaviors and actors, therefore, studying them as a coherent whole or just analyzing one part by taking into account the high degree of integration among the different aspects and actors linked by a flow of activities, information, and interactions is a bet lost in advance without a well-defined design process. Several design approaches and methodologies have been proposed over the years, but nonetheless, there is still no agreement on how to conduct modeling of complex systems because they are of different kinds. In this line, this paper proposes a top-down approach for container and Ro-Ro terminals largely inspired by the Unified Process Methodology and refined through several research projects that we have been involved in. It gives some recommendations and guidelines as well as a helpful way to successfully build modular and consistent simulation models. To prove its efficiency, it was applied to a case study and the resulting models were validated by the subject matter's experts.

  • 14.
    Abourraja, Mohamed Nezar
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics. Ecole Cent Casablanca, Casablanca, Morocco..
    Rouky, Naoufal
    Euro-Mediterranean University, Fez, Morocco.
    Kornevs, Maksims
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Meijer, Sebastiaan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Kringos, Nicole
    KTH, School of Architecture and the Built Environment (ABE), Civil and Architectural Engineering, Structural Engineering and Bridges. Euro Mediterranean Univ, Fes, Morocco..
    A simulation-based decision support framework devoted to Ro-Ro terminals: Design, implementation and evaluation2023In: Computers & industrial engineering, ISSN 0360-8352, E-ISSN 1879-0550, Vol. 180, p. 109248-, article id 109248Article in journal (Refereed)
    Abstract [en]

    As a type of intermodal terminal, pure Ro-Ro terminals are one of the most important logistic hubs in the supply chain for rolling freight stored in containerized and wheeled steel boxes. These large-scale systems are highly complex, with nonlinear and hard-to-predict behavior evolving in a stochastic environment. Consequently, making decisions about any problem thereof is no mean feat, particularly for terminal planners. To assist them in decision-making, a pool of relevant models and tools have been developed over the years in the literature. Nevertheless, models that are oriented toward specific objectives dominate, and generic ones are rare. This paper tries to fill this gap and proposes a generic framework to be used as a factory to create specific decision support models based on simulation for pure Ro-Ro terminals. This framework is formulated following two artifacts: (1) the known classification of key performance indicators combined with the typical functional and physical organization of pure Ro-Ro terminals; (2) the three main arteries of harbor systems, namely flows, decisions and operations. Then a scalable way of making decisions based on a flexible form of the cost function weighted according to a set of coefficients is integrated. These designed coefficients allow decision-makers a wide flexibly in choosing how the best solutions are determined. An application of this framework is illustrated through a real case study, where the weights are estimated using an expert-profiling based approach then pushed into the OptQuest optimizer to be calibrated before analyzing the results. These results are aggregated, then expressed as scores on a scale of 0 to 1. This is to help terminal planners to easily identify the worst and best planning scenarios as well as the relationships and compatibilities between the involved handling rules to suggest different alternatives for managing operations.

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

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

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    Examensarbete
  • 16. 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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  • 17.
    Abtahi, Farhad
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics. Karolinska Inst, Inst Environm Med, S-17165 Stockholm, Sweden..
    Lu, Ke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Diaz-Olivares, Jose A.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Forsman, Mikael
    Karolinska Inst, Inst Environm Med, S-17165 Stockholm, Sweden..
    Seoane, Fernando
    Karolinska Inst, Dept Clin Sci Intervent & Technol, Halsovagen 7, S-14157 Stockholm, Sweden.;Univ Boras, Swedish Sch Text, Allegatan 1, S-50190 Boras, Sweden.;Karolinska Univ Hosp, Dept Biomed Engn, S-17176 Solna, Sweden..
    Lindecrantz, Kaj
    Karolinska Inst, Inst Environm Med, S-17165 Stockholm, Sweden.;Univ Boras, Sci Pk,Allegatan 1, S-50190 Boras, Sweden..
    Wearable Sensors Enabling Personalized Occupational Healthcare2018In: INTELLIGENT ENVIRONMENTS 2018 / [ed] Chatzigiannakis, I Tobe, Y Novais, P Amft, O, IOS PRESS , 2018, p. 371-376Conference paper (Refereed)
    Abstract [en]

    This paper presents needs and potentials for wearable sensors in occupational healthcare. In addition, it presents ongoing European and Swedish projects for developing personalized, and pervasive wearable systems for assessing risks of developing musculoskeletal disorders and cardiovascular diseases at work. Occupational healthcare should benefit in preventing diseases and disorders by providing the right feedback at the right time to the right person. Collected data from workers can provide evidence supporting the ergonomic and industrial tasks of redesigning the working environment to reduce the risks.

  • 18.
    Abtahi, Jahan
    et al.
    Linköping Univ, Dept Oral & Maxillofacial Surg, Linköping, Sweden.;Linköping Univ, Dept Biomed & Clin Sci, Linköping, Sweden.;Linköping Univ, Ctr Med Image Sci & Visualizat CMIV, Linköping, Sweden..
    Klintström, Benjamin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Klintström, Eva
    Linköping Univ, Ctr Med Image Sci & Visualizat CMIV, Linköping, Sweden.;Linköping Univ, Dept Radiol, Linköping, Sweden.;Linköping Univ, Dept Hlth Med & Caring Sci, Linköping, Sweden..
    Ibandronate Reduces the Surface Bone Resorption of Mandibular Bone Grafts: A Randomized Trial With Internal Controls2021In: JBMR Plus, ISSN 2473-4039, Vol. 5, no 3, article id e10468Article in journal (Refereed)
    Abstract [en]

    Autologous bone grafts are considered the gold standard for reconstruction of the edentulous alveolar ridges. However, this procedure is associated with unpredictable bone loss caused by physiological bone resorption. Bisphosphonates are antiresorptive drugs that act specifically on osteoclasts, thereby maintaining bone density, volume, and strength. It was hypothesized that the resorption of bone grafts treated with an ibandronate solution would be less advanced than bone grafts treated with saline. Ten patients who underwent bilateral sagittal split osteotomy were included in a randomized double-blind trial with internal controls. Each patient received a bone graft treated with a solution of ibandronate on one side and a graft treated with saline (controls) contralaterally. Radiographs for the measurement of bone volume were obtained at 2 weeks and at 6 months after surgery. The primary endpoint was the difference in the change of bone volume between the control and the ibandronate bone grafts 6 months after surgery. All of the bone grafts healed without complications. One patient was excluded because of reoperation. In eight of the nine patients, the ibandronate bone grafts showed an increase in bone volume compared with baseline, with an average gain of 126 mm(3) (40% more than baseline) with a range of +27 to +218 mm(3). Only one ibandronate-treated graft had a decrease in bone volume (8%). In the controls, an average bone volume loss of -146 mm(3) (58% of baseline) with a range of -29 to -301 mm(3) was seen. In the maxillofacial field, the reconstructions of atrophic alveolar ridges, especially in the esthetical zones, are challenging. These results show that bone grafts locally treated with ibandronate solution increases the remaining bone volume. This might lead to new possibilities for the maxillofacial surgeons in the preservation of bone graft volumes and for dental implant installations.

  • 19.
    Adolfsson, Tobias
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Dellenby, Axel
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Pre-study of optical LED units for shunting signals2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Alstom wanted to investigate the possibility of adapting its light emitting diode (LED) technology for shunting signals in train traffic. The LED technology uses 50V, but Alstom wants to adapt it for 12V. The LED technology is energy efficient but needs to be adapted for existing signal interlocking by drawing a higher current. This meant that the possibility of reactive power compensation was investigated to obtain lower thermal dissipation in dwarf signal. The essay presents a couple of possible solutions. One of the solutions is to raise the voltage by using a booster converter to use the existing 50V LED unit. Capacitors were reviewed to be used in reactive power compensation to increase current supply. One of the solutions then became a capacitor bank. Simulations indicated that a booster converter and a capacitor bank can be used to adapt the circuit. However, some modifications must be made.

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  • 20.
    Adugna, Leykun
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Laic, Goran
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Kan projekt med öppen källkod användas delvis eller helt för at tuppfylla behoven för routing-applikationer?2020Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Companies are looking into the open source community in the hope of finding a better alternative software to replace their existing software suit. They are looking for software that has the necessary properties required to run their business and possibly help them avoid unnecessary costs and save time. This thesis has examined the needs of routing application for companies and presented a suggestion by using self-developed testbed. The testbed can be used by companies to decide the beneficial of implementing the desired routing application software. The routing application that gave the best result in this study is FRRouting (Free Range Routing).

    The solution proposed by the study has been proven to be effective through a pilot project where open source program has been successful by retaining the expected quality, functionality in a cost-effective way.

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  • 21.
    Aghdam, Araz Sheibani
    et al.
    Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey..
    Ghorbani, Morteza
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems. Sabanci Univ, Fac Engn & Nat Sci, Mechatron Engn Program, TR-34956 Istanbul, Turkey;Sabanci Univ, Ctr Excellence Funct Surfaces & Interfaces NanoDi, TR-34956 Istanbul, Turkey..
    Deprem, Gokberk
    Sabanci Univ, Fac Engn & Nat Sci, Mechatron Engn Program, TR-34956 Istanbul, Turkey..
    Cebeci, Fevzi Cakmak
    Sabanci Univ, Fac Engn & Nat Sci, TR-34956 Istanbul, Turkey.;Sabanci Univ, SUNUM Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey..
    Kosar, Ali
    Sabanci Univ, Fac Engn & Nat Sci, Mechatron Engn Program, TR-34956 Istanbul, Turkey.;Sabanci Univ, Ctr Excellence Funct Surfaces & Interfaces NanoDi, TR-34956 Istanbul, Turkey.;Sabanci Univ, SUNUM Nanotechnol Res & Applicat Ctr, TR-34956 Istanbul, Turkey..
    A New Method for Intense Cavitation Bubble Generation on Layer-by-Layer Assembled SLIPS2019In: Scientific Reports, E-ISSN 2045-2322, Vol. 9, article id 11600Article in journal (Refereed)
    Abstract [en]

    The importance of surface topology for the generation of cavitating flows in micro scale has been emphasized during the last decade. In this regard, the utilization of surface roughness elements is not only beneficial in promoting mass transportation mechanisms, but also in improving the surface characteristics by offering new interacting surface areas. Therefore, it is possible to increase the performance of microfluidic systems involving multiphase flows via modifying the surface. In this study, we aim to enhance generation and intensification of cavitating flows inside microfluidic devices by developing artificial roughness elements and trapping hydrophobic fluorinated lubricants. For this, we employed different microfluidic devices with various hydraulic diameters, while roughness structures with different lengths were formed on the side walls of microchannel configurations. The surface roughness of these devices was developed by assembling various sizes of silica nanoparticles using the layer-by-layer technique (D2). In addition, to compare the cavitating flow intensity with regular devices having plain surfaces (D1), highly fluorinated oil was trapped within the pores of the existing thin films in the configuration D2 via providing the Slippery Liquid-Infused Porous Surface (D3). The microfluidic devices housing the short microchannel and the extended channel were exposed to upstream pressures varying from 1 to 7.23 MPa. Cavitation inception and supercavitation condition occured at much lower upstream pressures for the configurations of D2 and D3. Interestingly, hydraulic flip, which rarely appears in the conventional conical nozzles at high pressures, was observed at moderate upstream pressures for the configuration D2 proving the air passage existence along one side of the channel wall.

  • 22.
    Ahlgren, Kajsa
    et al.
    Chalmers Univ Technol, Dept Phys, Div Nanobiophys, SE-41296 Gothenburg, Sweden..
    Olsson, Christoffer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Ermilova, Inna
    Chalmers Univ Technol, Dept Phys, Div Nanobiophys, SE-41296 Gothenburg, Sweden..
    Swenson, Jan
    Chalmers Univ Technol, Dept Phys, Div Nanobiophys, SE-41296 Gothenburg, Sweden..
    New insights into the protein stabilizing effects of trehalose by comparing with sucrose2023In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 25, no 32, p. 21215-21226Article in journal (Refereed)
    Abstract [en]

    Disaccharides are well known to be efficient stabilizers of proteins, for example in the case of lyophilization or cryopreservation. However, although all disaccharides seem to exhibit bioprotective and stabilizing properties, it is clear that trehalose is generally superior compared to other disaccharides. The aim of this study was to understand this by comparing how the structural and dynamical properties of aqueous trehalose and sucrose solutions influence the protein myoglobin (Mb). The structural studies were based on neutron and X-ray diffraction in combination with empirical potential structure refinement (EPSR) modeling, whereas the dynamical studies were based on quasielastic neutron scattering (QENS) and molecular dynamics (MD) simulations. The results show that the overall differences in the structure and dynamics of the two systems are small, but nevertheless there are some important differences which may explain the superior stabilizing effects of trehalose. It was found that in both systems the protein is preferentially hydrated by water, but that this effect is more pronounced for trehalose, i.e. trehalose forms less hydrogen bonds to the protein surface than sucrose. Furthermore, the rotational motion around dihedrals between the two glucose rings of trehalose is slower than in the case of the dihedrals between the glucose and fructose rings of sucrose. This leads to a less perturbed protein structure in the case of trehalose. The observations indicate that an aqueous environment closest to the protein molecules is beneficial for an efficient bioprotective solution.

  • 23.
    Ahluwalia, A.
    et al.
    Italy.
    De Maria, C.
    Italy.
    Lantada, A. D.
    Spain.
    Pietro, L. D.
    Italy.
    Ravizza, A.
    Italy.
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Madete, J.
    Kenya.
    Makobore, P. N.
    Uganda.
    Aabloo, A.
    Estonia.
    Kitsing, R.
    Estonia.
    Leivobits, A.
    Estonia.
    Towards open source medical devices current situation, inspiring advances and challenges2018In: BIODEVICES 2018 - 11th International Conference on Biomedical Electronics and Devices, Proceedings; Part of 11th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2018, SciTePress, 2018, p. 141-149Conference paper (Refereed)
    Abstract [en]

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

  • 24.
    Ahluwalia, Arti
    et al.
    Univ Pisa, Dept Ingn Informaz, Bioengn, Pisa, Italy..
    De Maria, Carmelo
    Univ Pisa, Dept Ingn Informaz, Bioengn, Pisa, Italy..
    Diaz Lantada, Andres
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Madete, June
    Univ Pisa, Res Ctr E Piaggio, Pisa, Italy.;Kenyatta Univ, Nairobi, Kenya..
    Makobore, Philippa Ngaju
    Uganda Ind Res Inst, Instrumentat Div, Kampala, Uganda..
    Ravizza, Alice
    Univ Pisa, Pisa, Italy..
    Di Pietro, Licia
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Munoz-Guijosa, Juan Manuel
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Tanarro, Enrique Chacon
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Torop, Janno
    Tartu Ulikool, Inst Technol, Tartu, Estonia..
    Biomedical Engineering Project Based Learning: Euro-African Design School Focused on Medical Devices2018In: International Journal of Engineering Education, ISSN 0949-149X, Vol. 34, no 5, p. 1709-1722Article in journal (Refereed)
    Abstract [en]

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

  • 25. Ahmad, Amais
    et al.
    Pepin, Xavier
    Aarons, Leon
    Wang, Yuya
    Darwich, Adam S.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Wood, J. Matthew
    Tannergren, Christer
    Karlsson, Eva
    Patterson, Claire
    Thörn, Helena
    Ruston, Linette
    Mattinson, Alex
    Carlert, Sara
    Berg, Staffan
    Murphy, Donal
    Engman, Helena
    Laru, Johanna
    Barker, Ric
    Flanagan, Talia
    Abrahamsson, Bertil
    Budhdeo, Shanoo
    Franek, Frans
    Moir, Andrea
    Hanisch, Gunilla
    Pathak, Shriram M.
    Turner, David
    Jamei, Masoud
    Brown, Jonathan
    Good, David
    Vaidhyanathan, Shruthi
    Jackson, Claire
    Nicolas, Olivier
    Beilles, Stephane
    Nguefack, Jean-Flaubert
    Louit, Guillaume
    Henrion, Louis
    Ollier, Celine
    Boulu, Laurent
    Xu, Christine
    Heimbach, Tycho
    Xiojun, Ren
    Lin, Wen
    Nguyen-Trung, Anh-Thu
    Zhang, Jin
    He, Handan
    Wu, Fan
    Bolger, Michael B.
    Mullin, James M.
    van Osdol, Bill
    Szeto, Ke
    Korjamo, Timo
    Pappinen, Sari
    Tuunainen, Johanna
    Zhu, Wei
    Xia, Binfeng
    Daublain, Pierre
    Wong, Suet
    Manthena, Varma
    Modi, Sweta
    Schäfer, Kerstin Julia
    Schmid, Katrin
    Lloyd, Richard
    Patel, Aarti
    Tistaert, Christophe
    Bevernage, Jan
    Nguyen, Mai Anh
    Lindley, David
    Carr, Robert
    Rostami-Hodjegan, Amin
    IMI – Oral biopharmaceutics tools project – Evaluation of bottom-up PBPK prediction success part 4: Prediction accuracy and software comparisons with improved data and modelling strategies2020In: European journal of pharmaceutics and biopharmaceutics, ISSN 0939-6411, E-ISSN 1873-3441, Vol. 156, p. 50-63Article in journal (Refereed)
    Abstract [en]

    Oral drug absorption is a complex process depending on many factors, including the physicochemical properties of the drug, formulation characteristics and their interplay with gastrointestinal physiology and biology. Physiological-based pharmacokinetic (PBPK) models integrate all available information on gastro-intestinal system with drug and formulation data to predict oral drug absorption. The latter together with in vitro-in vivo extrapolation and other preclinical data on drug disposition can be used to predict plasma concentration-time profiles in silico. Despite recent successes of PBPK in many areas of drug development, an improvement in their utility for evaluating oral absorption is much needed. Current status of predictive performance, within the confinement of commonly available in vitro data on drugs and formulations alongside systems information, were tested using 3 PBPK software packages (GI-Sim (ver.4.1), Simcyp® Simulator (ver.15.0.86.0), and GastroPlusTM (ver.9.0.00xx)). This was part of the Innovative Medicines Initiative (IMI) Oral Biopharmaceutics Tools (OrBiTo) project.

    Fifty eight active pharmaceutical ingredients (APIs) were qualified from the OrBiTo database to be part of the investigation based on a priori set criteria on availability of minimum necessary information to allow modelling exercise. The set entailed over 200 human clinical studies with over 700 study arms. These were simulated using input parameters which had been harmonised by a panel of experts across different software packages prior to conduct of any simulation. Overall prediction performance and software packages comparison were evaluated based on performance indicators (Fold error (FE), Average fold error (AFE) and absolute average fold error (AAFE)) of pharmacokinetic (PK) parameters.

    On average, PK parameters (Area Under the Concentration-time curve (AUC0-tlast), Maximal concentration (Cmax), half-life (t1/2)) were predicted with AFE values between 1.11 and 1.97. Variability in FEs of these PK parameters was relatively high with AAFE values ranging from 2.08 to 2.74. Around half of the simulations were within the 2-fold error for AUC0-tlast and around 90% of the simulations were within 10-fold error for AUC0-tlast. Oral bioavailability (Foral) predictions, which were limited to 19 APIs having intravenous (i.v.) human data, showed AFE and AAFE of values 1.37 and 1.75 respectively. Across different APIs, AFE of AUC0-tlast predictions were between 0.22 and 22.76 with 70% of the APIs showing an AFE > 1. When compared across different formulations and routes of administration, AUC0-tlast for oral controlled release and i.v. administration were better predicted than that for oral immediate release formulations. Average predictive performance did not clearly differ between software packages but some APIs showed a high level of variability in predictive performance across different software packages. This variability could be related to several factors such as compound specific properties, the quality and availability of information, and errors in scaling from in vitro and preclinical in vivo data to human in vivo behaviour which will be explored further. Results were compared with previous similar exercise when the input data selection was carried by the modeller rather than a panel of experts on each in vitro test. Overall, average predictive performance was increased as reflected in smaller AAFE value of 2.8 as compared to AAFE value of 3.8 in case of previous exercise.

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  • 26.
    Ahmed, Mohamed
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Medical Imaging.
    Medical Image Segmentation using Attention-Based Deep Neural Networks2020Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the last few years, segmentation architectures based on deep learning achieved promising results. On the other hand, attention networks have been invented years back and used in different tasks but rarely used in medical applications. This thesis investigated four main attention mechanisms; Squeeze and Excitation, Dual Attention Network, Pyramid Attention Network, and Attention UNet to be used in medical image segmentation. Also, different hybrid architectures proposed by the author were tested. Methods were tested on a kidney tumor dataset and against UNet architecture as a baseline. One version of Squeeze and Excitation attention outperformed the baseline. Original Dual Attention Network and Pyramid Attention Network showed very poor performance, especially for the tumor class. Attention UNet architecture achieved close results to the baseline but not better. Two more hybrid architectures achieved better results than the baseline. The first is a modified version of Squeeze and Excitation attention. The second is a combination between Dual Attention Networks and UNet architecture. Proposed architectures outperformed the baseline by up to 3% in tumor Dice coefficient. The thesis also shows the difference between 2D architectures and their 3D counterparts. 3D architectures achieved more than 10% higher tumor Dice coefficient than 2D architectures.

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  • 27.
    Ahmed, Redve
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Migration from Manual to Automatic Regression Testing: Best practices for Salesforce Test Automation2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The goal of this thesis is to explore the possibility on if it is possible to automate regression testing for a SaaS application with a serverless approach. The thesis covers the fundamentals of the software development lifecycle, cloud concepts, different types of testing frameworks, and SaaS applications. The report researches various testing tools that can be used in accordance with Polestar’s needs. The testing framework must run the existing tests and deliver the results of the tests. The system must be able to coexist with the testing strategy that is in place today. The result is a testing framework that can run a number of selected tests on the SaaS application Salesforce. The system was deployed with serverless docker containers through Amazon Web Services. The report also covers what a future implementation can look like and potential improvements. 

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    Migration from Manual to Automatic Regression Testing
  • 28.
    Akram, Muhammad
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Isocyanates formation from thermal degradation of polyurethane foam during welding of district heating pipes2023Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Polyurethane insulation foam, which is used as insulation on district heating steel and copper pipes, is made from polymerisation of polyol and diisocyanates monomers. Installation of new district heating pipes or replacement of old pipes involves masses of welding activities. Welding processes of pre-insulated district heating pipes can cause exposure of polyurethane insulation to high heat generated during the welding process. Temperatures of more than 150 °C can lead to thermal degradation of polyurethane insulation and isocyanates formation. Exposure of isocyanates to welders can cause allergy, irritation of eyes, nose, throat, skin, and lung problems, and isocyanate asthma. In this thesis project welding processes of varying nominal sizes of district heating pipes, varying welding method and consequential formation of isocyanates have been studied. This project has found that selection of welding method plays a key role in the formation of isocyanates. It was identified that although the oxy-fuel welding method is considered as easy method for welding, there is a generation of high heat. This since oxy-fuel welding warm up the district heating pipes to high temperatures, which lead to thermal exposure of polyurethane insulation and ultimate formation of hazardous isocyanates. Other aspect such as varying nominal sizes of the pipes and varying length of insulation-free ends effect the exposure of polyurethane insulation to high heat and eventual formation of isocyanates. This study found that small nominal sizes of district heating pipes DN20, DN25, DN32, DN50, DN65, DN80 of insulation-free ends from 20 to 22 cm, welded by oxy-fuel welding, have a low risk to generate critical high heat 150 °C. But if the length of the insulation-free ends is reduced to 16 cm it can lead to thermal degradation of polyurethane insulation and isocyanates formation. For air samples of isocyanates collected during welding of nominal pipe sizes DN100, DN150, DN200 having insulation-free ends 22-20 cm welded by oxy-fuel welding, the analysis showed notable types of monoisocyanates MIC, PHI, ICA and diisocyanates 4.4´-MDI. The concentration of the detected monoisocyanates ICA and diisocyanates 4.4´-MDI in some samples were higher than the acceptable short-term exposure limit STEL (μg / m3) determined by AFS 2018:1. The presence of large fractions of isocyanates in samples collected from surroundings of high-temperature-exposed polyurethane insulation showed high risks of isocyanates exposure to welders.

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  • 29.
    Al Khateeb, Ahmad
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Summaq, Abdulrazzaq
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Securing Data in a Cloud Environment: Access Control, Encryption, and Immutability2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The amount of data and the development of new technologies used by all society-critical organizations are increasing dramatically. In parallel, data breaches, cyber-attacks, and their devastating consequences are also on the rise, as well as the number of individuals and organizations that are potential targets for such attacks. This places higher demands on security in terms of protecting data against cyber-attacks and controlling access to data that authenticated users want to access. The paper focuses on studying concepts of secure data practices in a GitLab-based cloud environment. The objective is to give answers to questions such as how to ensure the guarantee of secure data and protect it from unauthorized access and changes. The work behind this thesis includes exploring techniques for access control, data encryption, and data immutability. The study is followed by an implementation project that includes fetching code from GitLab verifying user identity and access control, managing data access, and displaying the results. The results of the thesis demonstrate the effectiveness of the implemented security measures in protecting data and controlling access.

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    Examensarbetesrapport
  • 30.
    Alastair, Kerr
    et al.
    karolinska institutet.
    Wang, Zuoneng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Na, Wang
    karolinska institutet.
    Kwok, Kelvin
    karolinska institutet.
    Jalkanen, Jutta
    karolinska institutet.
    Ludzki, Alison
    karolinska institutet.
    Langin, Dominique
    Bergö, Martin
    karolinska institutet.
    Dahlman, Ingrid
    karolinska institutet.
    Mim, Carsten
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Structural Biotechnology.
    Arner, Peter
    karolinska institutet.
    Gao, Hui
    karolinska institutet.
    The long noncoding RNA ADIPINT is a gatekeeper of pyruvate carboxylasefunction regulating human fat cell metabolismManuscript (preprint) (Other academic)
    Abstract [en]

    The pleiotropic function of long noncoding RNAs (lncRNAs) is well recognized,but their direct role in governingmetabolic homeostasis is less understood. Herein,we describe a human adipocyte-specific lncRNA, ADIPINT, that regulatespyruvate carboxylase (PC) an enzyme pivotal to energy metabolism. With a novelapproach, Targeted RNA-protein identification using Orthogonal Organic PhaseSeparation (TROOPS) and validation with electron microscopy, we show thatADIPINT binds to PC. ADIPINT knockdown alters the interactome anddecreases the mitochondrial abundance and enzymatic activty of PC. Decreases inADIPINT or PC expression reduce adipocyte lipid synthesis, breakdown and lipidcontent. In human white adipose tissue, ADIPINT expression is increased inobesity, linked to fat cell size, adipose insulin resistance and PC activity. Thus, weidentify ADIPINT as a regulator of lipid metabolism in human white adipocytes,which at least in part is mediated through its interaction with PC.

  • 31. Al-Ayyad, M.
    et al.
    Al-Ghraibah, A.
    Alkhatib, Husam
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Transportation of donated hearts by drone in comparison to road-bound vehicles in Mexico city2019In: Open Biomedical Engineering Journal, E-ISSN 1874-1207, Vol. 13, no 1, p. 142-150Article in journal (Refereed)
    Abstract [en]

    Background: Organ transportation between hospitals has many challenges since the harvested organ needs to be transplanted to the recipient within an optimal time frame. It is important to transfer the organ from the donor to the recipient site quickly and professionally. Aim: The aim of this research is to investigate whether the transportation of donated hearts by drones is more efficient than transportation using roadbound vehicles. Methods: A simulation using MatLab software was performed to calculate the heart transportation time between three different hospitals in Mexico City by road-bound vehicles and by drones. This simulation was performed to demonstrate how congestion and traffic in Mexico City prevent healthy hearts from being transplanted to patients on time. The 24-hour period was divided into four 5-hour periods and these were chosen to be: Period 1 (22:00-03:00), Period 2 (04:00-09:00), Period 3 (10:00-15:00) and Period 4 (16:00-21:00). Results: The time it took to travel between the hospitals by car within each of the 5-hour periods was calculated. It was observed that, in period 2, a high volume of traffic was present causing road-bound vehicles to take a longer time to deliver hearts to hospitals. All hospitals were within reach of each other if the hearts were to be transported by drone and the delivery time by drone in all cases was less than 1.88 hours, which is the optimum time for the harvested heart to be transported without risk from the donor to the recipient. Conclusion: Using drones will increase the safety of transplants, reduce the heart transplantation waiting list and eventually, heart transplantation may be possible in different areas of the city at rush hour times. 

  • 32.
    Albaaj, Hussein
    et al.
    Department of Global Public Health, Karolinska Institutet, Solna, Sweden.
    Attergrim, Jonatan
    Department of Global Public Health, Karolinska Institutet, Solna, Sweden; Perioperative Medicine and Intensive Care, Karolinska University Hospital, Solna, Sweden.
    Strömmer, Lovisa
    Division of Surgery, Department of Clinical Science, Intervention and Technology (CLINTEC), Karolinska Institutet, Stockholm, Sweden.
    Brattström, Olof
    Perioperative Medicine and Intensive Care, Karolinska University Hospital, Solna, Sweden; Department of Physiology and Pharmacology, Karolinska Institutet, Stockholm, Sweden.
    Jacobsson, Martin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Wihlke, Gunilla
    Trauma and Reparative Medicine, Karolinska University Hospital, Solna, Sweden.
    Västerbo, Liselott
    Trauma and Reparative Medicine, Karolinska University Hospital, Solna, Sweden.
    Joneborg, Elias
    Department of Global Public Health, Karolinska Institutet, Solna, Sweden.
    Gerdin Wärnberg, Martin
    Department of Global Public Health, Karolinska Institutet, Solna, Sweden; Perioperative Medicine and Intensive Care, Karolinska University Hospital, Solna, Sweden.
    Patient and process factors associated with opportunities for improvement in trauma care: a registry-based study2023In: Scandinavian Journal of Trauma, Resuscitation and Emergency Medicine, E-ISSN 1757-7241, E-ISSN 1757-7241, Vol. 31, no 1, article id 87Article in journal (Refereed)
    Abstract [en]

    Background Trauma is one of the leading causes of morbidity and mortality worldwide. Morbidity and mortality review of selected patient cases is used to improve the quality of trauma care by identifying opportunities for improvement (OFI). The aim of this study was to assess how patient and process factors are associated with OFI in trauma care.

    Methods We conducted a registry-based study using all patients between 2017 and 2021 from the Karolinska University Hospital who had been reviewed regarding the presence of OFI as defined by a morbidity and mortality conference. We used bi- and multivariable logistic regression to assess the associations between the following patient and process factors and OFI: age, sex, respiratory rate, systolic blood pressure, Glasgow Coma Scale (GCS), Injury Severity Score (ISS), survival at 30 days, highest hospital care level, arrival on working hours, arrival on weekends, intubation status and time to first computed tomography (CT).

    Results OFI was identified in 300 (5.8%) out of 5182 patients. Age, missing Glasgow Coma Scale, time to first CT, highest hospital care level and ISS were statistically significantly associated with OFI.

    Conclusion Several patient and process factors were found to be associated with OFI, indicating that patients with moderate to severe trauma and those with delays to first CT are at the highest odds of OFI.

  • 33.
    Albaloua, Mark
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Kizilkaya, Kenan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Användning av högnivåspråket Swift i webbläsaren och i Android: En studie på möjligheterna att återanvända högnivåspråket Swift utanför iOS i andra plattformar som webbläsare och Android2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The purpose of this work was to study the possibilities of using the high-level language Swift outside of iOS in the browser and on Android. This is to reduce the amount of code written thus reducing development time to create applications for iOS, browser, and Android. To find suitable tools to solve the problem, a study on previous works and methods has been made. The results of the study led to the use of the framework Tokamak together with WebAssembly to reuse Swift in the browser and the tool SwiftKotlin to reuse Swift on Android.

    An application using the Model-View-ViewModel (MVVM) design pattern was created with the intention of testing reusability. The results showed that Tokamak with WebAssembly made it possible to use all the code from the original iOS application except platform-specific functions such as local saving and network calls. SwiftKotlin made it possible to reuse the model class with some small adjustments while the viewmodel and view classes must be manually written. 

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  • 34.
    Alberico, Gennaro
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Development of an intervention framework for design, implementation and adoption of occupational exoskeletons2022Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    During the last few years, wearable technologies or body-worn assistive devices have become very popular within the occupational field. Among them, there are the so-called exoskeletons which have shown a promising potential in several areas ranging from medical care, military to, particularly during the last five years, industrial applications. In this sense, exoskeleton could represent a novel technical solution, with the potential to tackle the perennial problem of work-related musculoskeletal disorders. However, within the industrial field, there are still issues to be addressed such as exoskeletons’ long-term effects and adaptation to multiple tasks. This should be done through multiyear and extensive studies in real-life scenarios, to avoid that any issues pertaining to the individual, group or organizational level, could be overlooked.

    This thesis aimed to investigate factors that can promote or hinder the implementation of exoskeletons from a ‘‘whole system approach’’. To achieve this, first, a literature review was conducted in order to provide an overview of key findings from ongoing research about industrial exoskeletons. These key findings, which included current trends and knowledge gaps, formed the theoretical basis of this study. This was used in the development of an interview guide, which was used in semi-structured interviews. Thus, through qualitative interviewing, the key findings from the theoretical basis were further investigated. Moreover, once the data was gathered, the interviews were analyzed in depth and a content analysis of the interviews was systematically carried out, in order to find emerging “themes”. Furthermore, these ‘‘themes’’ were used to investigate underlying norms, contextual factors and challenges that exoskeletons may pose. Finally, the main ‘‘themes’’ and the key findings from the theoretical basis, were integrated into an intervention framework, the development of which was the secondary aim of this study. The new framework was designed aiming to guide policy makers, management, and personnel in planning, designing, and implementing ergonomic interventions through exoskeletons.

    The results of this study showed that safety, comfort, and fit are major factors in driving the adoption and acceptance of occupational exoskeletons. At the center of this suggested trifecta, there is productivity. However, when productivity is prioritized over the safety and the well-being of the workers, an “ergonomic pitfall” could be the consequence. It means the risk to add new constraints and challenges in the work environment, instead of reducing the physical workload and the muscle fatigue of the worker. Further, in terms of adoption barriers, the interviewees, in line with research in the field, stressed the importance to give enough time to the employees to familiarize themselves with the exoskeleton technology. In addition, since exoskeletons are introduced from the management side, it is key to effectively communicate the value proposition of exoskeletons, namely to protect worker’s health status rather than enable them to work at a higher pace or to handle heavier loads. In addition, based on the results of this study, practitioners should consider engaging in more inclusive dialogues with academia and policymakers to overcome the fragmentation of the exoskeletons’ market. Only by working in close collaboration with these stakeholders, and making full use of their experience and expertise, it can be possible in the near future to develop exoskeletons which are both aligned with workers’ and society needs, as well as with companies’ demands.

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  • 35.
    Aldahan, Leith
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Kudoori, Ivan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Utvärdering av roterande borstlösfrekvensomformare tillspårledningar2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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

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    Utvärdering av roterande borstlös fre-kvensomformare till spårledningar
  • 36.
    Alfrijat, Christopher
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Eriksson, Rasmus
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Analys och utvärdering av LED-belysning i Stockholms tunnelbana2019Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

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

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

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

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  • 37.
    Ali, Umar
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Sulaiman, Rabi
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Using UX design principles for comprehensive data visualisation2023Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Workplace safety, particularly in manual handling tasks, is a critical concern that hasbeen increasingly addressed using advanced risk assessment tools. However, pre-senting the complex results of these assessments in an easily digestible format re-mains a challenge. This thesis focused on designing and developing a user-friendlyweb application to visualise risk assessment data effectively. Grounded in a robusttheoretical framework that combines user experience principles, and data visualisa-tion techniques. The study employed an iterative, user-centric design process to de-velop the web application. Multiple visualisation methods, such as pie charts for vis-ualising risk distribution, bar chart, and line chart for time-based analysis, were eval-uated for their effectiveness through usability testing. The application's primary con-tribution lies in its efficient data visualisation techniques, aimed at simplifying com-plex datasets into actionable insights. This work lays the groundwork enabling futuredevelopment by pinpointing areas for improvement like enhanced interactivity andaccessibility.

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  • 38.
    Alkass, Jakob
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    UX spelar roll: Förbättra prestanda hos webbsida för förbättrad användarupplevelse av webbapplikation.2022Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The company Telia has a web application that is under development and will serve as an internal portal for clients of the company. They experience a lack of performance in the frontend part of the application in the form of long loading times. They therefore want to explore possibilities for optimizing the performance of their web application in hope of improving the user experience. The goal was to investigate possibilities for the application of different optimization techniques that can improve parts of the performance with close connection to the user experience.

    For this thesis, previous research was examined in the field of user experience related to digital products. Research of similar work such as appropriate performance measures and optimization techniques was also conducted. To test, analyse and evaluate the optimization techniques, automatic tests were created that stored measurement data on selected performance metrics. Measurement data from the tests was then analysed in order to suggest further development for Telia’s web application. An analysis of the measurement data showed an overall improvement in Telia’s web application performance for the two examined performance metrics by 33% and 35%respectively. 

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  • 39.
    Alkhatib, Husam
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Developing an Optimal Design for A Heart Container Operated Via Drone2019Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

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

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  • 40.
    Alkhatib, Najla
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    A Simulation Game Approach for Improving Access to Specialized Healthcare Services in Sweden2024Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    In Sweden, where a decentralized healthcare system is applied, all patients are registered at a primary healthcare center. To access most of the publicly funded specialized care clinics, patients need to be referred by a general physician at the primary healthcare center. However, long waiting times and queues to access specialized care clinics in Sweden, has been a serious problem and concern for decades. Addressing this issue is important for improving patients’ transition to specialized care and the functionality of the Swedish healthcare system. The aim of this thesis is to explore the Swedish healthcare system to analyze the transition of patients to specialized care clinics and identify the reasons for long waiting times and queues. This was done by analyzing the Swedish healthcare system and develop a serious game prototype which models the process of access to specialized care within the Swedish healthcare system. The prototype was used to understand the delay that happens in patients’ transition and access process to specialized care services.  A system analysis including a literature review is conducted to gain an understanding of the Swedish healthcare system and gather data to be used in the designed prototype. The outcome of the system analysis is a visual representation of the Swedish healthcare system including laws and stakeholders. A game frame is developed from the system analysis. Maps, tables, and a flow-diagram are developed to visualize patients’ access to specialized care. All of this was used to design the game prototype. The final prototype is developed through an iterative process, where several prototypes are designed and tested through game sessions with experts. The prototypes are evaluated after each game session. Finally, learning and findings gained from the prototypes design and the game sessions are documented. This includes reasons for long waiting times for a first visit at a specialized care clinic such as the structure of the Swedish healthcare system, mainly that the PHC is the foundation of the system. Staff shortages, and the need for a referral to access most of the specialized clinics are also discussed and stated along with other reasons. 

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  • 41.
    Almosawi, Talib
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Karanta, George
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    ZigBee-based climate measurement system for thermal comfort in traffic busses2021Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis describes the work process two (WP2) of a project led by the traffic administration in Stockholm to achieve the passengers' thermal comfort in traffic buses. 

    The purpose of this thesis is to design and implement a measurement system comprised in eight measurement position in a bus. Each position is able to transmit data using a wireless communication protocol, with a central unit collecting all the transmitted data taking into consideration the accuracy of the measurements and filtering out the incorrect data.

    In order to accomplish this, a literature study is conducted investigating different measurement methods for different parameters, different communication protocols were analysed as well to determine an appropriate communication protocol suitable for climate measurement in a bus environment with passengers present on board. 

    The output of the HVAC system is also required to help the traffic administration demonstrate the results of adjusting the temperature in the bus to reach the thermal comfort and how it led to saving energy.

    The system incorporates ZigBee , ESP32 microcontroller in the sender positions and a Raspberry pi operating as a central unit to collect data and store it in a file system providing an accurate data that will help the traffic administration achieve their goals.

    Unfortunately, there were some diffculties accessing CAN system data to provide the output of the HVAC system.

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    ZigBee-based climate measurement system for thermal comfort in traffic busses
  • 42.
    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
    Download (zip)
    Filmer som används i mätverktyget
  • 43.
    Al-Robaye, Ali
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Svenska laddningsinfrastrukturen: Studie om hur den svenska laddningsinfrastrukturen måste utvecklas för att kunna tillgodose en fortsatt omställning av fossildrivna fordon till elektriska.2024Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The entire world is confronting new challenges as a result of climate change. To mitigate human impact on the climate, the European Union and Sweden, as an EU member state, have decided to phase out the use of fossil fuels. The transition from fossil-fueled vehicles to electric ones has commenced, but Sweden is currently far from achieving a complete transition. The prerequisite for a complete transition is the establishment of a functional charging infrastructure capable of handling the increasing demand for charging. This report examines the current state of the Swedish charging infrastructure, highlights the factors hindering further development, and concludes by outlining the necessary steps for the Swedish charging infrastructure to facilitate transitions of 50-, 75-, and 100-percent from fossil-fueled to electric vehicles. Based on this analysis, it is evident that investments in public and home charging are critical factors at all levels of transition. Transparency and collaboration are currently lacking but are essential elements that must be in place for a successful and complete transition.

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  • 44.
    Alsaeede, Mustafa
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Test and Evaluation of a Novel Passive Tool Used For Blood Dilution in Hematology Analyzers2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Executive Summary

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

     

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

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

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    Thesis Report/ Mustafa Alsaeede
  • 45.
    Altuni, Bestun
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Aman Ali, Jasin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Segmentering av medicinska bilder med inspiration från en quantum walk algoritm2023Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Currently, quantum walk is being explored as a potential method for analyzing medical images. Taking inspiration from Grady's random walk algorithm for image processing, we have developed an approach that leverages the quantum mechanical advantages inherent in quantum walk to detect and segment medical images. Furthermore, the segmented images have been evaluated in terms of clinical relevance. Theoretically, quantum walk algorithms have the potential to offer a more efficient method for medical image analysis compared to traditional methods of image segmentation, such as classical random walk, which do not rely on quantum mechanics. Within this field, there is significant potential for development, and it is of utmost importance to continue exploring and refining these methods. However, it should be noted that there is a long way to go before this becomes something that can be applied in a clinical environment.

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  • 46.
    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. 

  • 47.
    Alvarez, Victor S
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Kleiven, Svein
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Effect of pediatric growth on cervical spine kinematics and deformations in automotive crashes2018In: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 71, p. 76-83, article id S0021-9290(18)30075-7Article in journal (Refereed)
    Abstract [en]

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

  • 48.
    Al-Wendawi, Kamal
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Faradj, Dyar
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Smartare resursfördelning med hjälp av djup maskininlärning2020Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    AbstractThis thesis has been carried out on behalf of Stanley Security Sverige AB. The company Stanley provides a product to calculate the number of people in a queue. The product detects the number of people in a queue with the help of a surveillance camera and deep machine learning. They find that the existing solution does not perform well enough to be deployed and does not detect with high accuracy. In this work, various known object recognition models have been examined and compared, as well as examination of previous work and tests in the field.The result was a reconfigured model prototype that only detected faces in comparison to known models You Only Look Once V3 (YOLOV3) and Single Shot MultiBox Detector (SSD) that detect the entire human body, in addition to other objects. The proposed model performed significantly better than the known models and had higher accuracy. The results indicate that the proposed model prototype can be deployed in real time and be used by Stanely's customers to efficiently allocate resources within their companies.Keywordsmachine learning, image analysis, Python, Darknet, neural network, deep learning, YOLOV3, Single Shot MultiBox Detector.

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    fulltext
  • 49.
    Alyoussef, Elyas
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Kategorisering på uppfattningar om digitala hot på webbapplikationer: Med en studie som visar de ekonomiska konsekvenserna av cyberattacker2022Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This thesis presents a categorization of conceptions about digital threats on web applications with a study showing the economic consequences of cyber-attacks. The aim of this thesis is to contribute to a scientific article, which can be valuable to the public, as well as for future work and employment.

    Constant comparison method was used to analyse aggregate perceptions. The results reveal several exciting findings for theory and practice, where perceptions of the cyber world were presented in order to understand more how others see cybersecurity today. It also shows significant variations among the participants' perceptions. This shows that information security, even if it is gradually developed, has a long way to go until it becomes an unbroken part of the business. 

    This study can also serve as a guide for the different perceptions of cyber-attacks as it provides an overview of the most relevant cyber-attacks today. This thesis was supplemented with a study that highlights the economic consequences of cyberattacks. In addition to this, the cyber-attack on Coop during the summer of 2021 was also studied. 

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

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

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