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  • 251.
    Larsson, Tore J
    et al.
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    m.fl, m.fl
    Allvarliga arbetsskador och långvarig sjukfrånvaro i Sverige 2002: Severe work-related injury and long-term absence from work in Sweden 20022002Report (Other academic)
  • 252.
    Larsson, Tore J
    et al.
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    m.fl, m.fl
    Allvarliga arbetsskador och långvarig sjukfrånvaro i Sverige 20062006Report (Other academic)
  • 253.
    Larsson, Tore J
    et al.
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Normark, M
    Oldertz, C
    Tezic, K
    Allvarliga arbetsskador och långvarig sjukfrånvaro 20092009Report (Other academic)
  • 254.
    Larsson, Tore J
    et al.
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Normark, M
    Oldertz, C
    Tezic, K
    Allvarliga arbetsskador och långvarig sjukfrånvaro 20102010Report (Other academic)
  • 255.
    Larsson, Tore J
    et al.
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Normark, M
    AFA Insurances Sweden.
    Oldertz, Cecilia
    AFA Insurances Sweden.
    Tezic, K
    AFA Insurances Sweden.
    Allvarliga arbetsskador och långvarig sjukfrånvaro 2011: Severe work-related injury and long-term absence from work in 2011 (In Swedish)2011Report (Other academic)
  • 256.
    Larsson, Tore J
    et al.
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Normark, M
    Paulsson, PA
    Åkerström, T
    Allvarliga arbetsskador och långvarig sjukfrånvaro 2013: Severe work-related injury and long-term absence from work in 2013, in Swedish2013Report (Other academic)
  • 257.
    Larsson, Tore J
    et al.
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Normark, M
    Weigelt, A
    Åkerström, T
    Allvarliga arbetsskador och långvarig sjukfrånvaro - 20122012Report (Other academic)
  • 258.
    Laya, Andrés
    et al.
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Markendahl, Jan
    KTH, School of Information and Communication Technology (ICT), Communication Systems, CoS, Radio Systems Laboratory (RS Lab).
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Network-Centric Business Models for Health, Social Care and Wellbeing Solutions in the Internet of ThingsManuscript (preprint) (Other academic)
    Abstract [en]

    In this multiple case study we analyze solutions based on connected devices in the context of health, social care and wellbeing. Based on the consideration that a solution is a combination of services and products, we build on the notion that business models can be studied at a firm- and a network-level. These two levels are used to motivate the reasons why solutions emerging at the intersection of the healthcare and the ICT industries benefit from collaboration among different actors. We conclude that the firm- and the network-level development of business models provide alignment in the business network and are useful to establish the relation that technological component have with overall solutions. Our findings suggest that some component bring novelty in the final offer with affecting the ongoing operation, while other component aim at improving the internal working processes, with minimal effects on the final offer to end users. We discuss the benefits of a network-level perspective for each case.

  • 259. Levin, Britta
    et al.
    Tribukait, Arne
    KTH, School of Technology and Health (STH), Environmental Physiology.
    Lemming, Dag
    Eiken, Ola
    KTH, School of Technology and Health (STH), Environmental Physiology.
    Utvärdering av utbildning i spatial desorientering; redovisning av frågeformulär2011Report (Other academic)
    Abstract [sv]

    En kombinerad grundutbildning i spatial desorientering (SD) och flygning med night vision goggles (NVG) ges av företaget AMST Systemtechnik GmbH i dess lokaler i Ranshofen i Österrike.Denna utbildning blev föremål för en ingående utvärdering i samband med att två grupper av svenska flygförare deltog under hösten 2010.Den del av utvärderingen som redovisas i denna rapport är baserad på deltagarnas egna åsikter och bygger på en metod som omfattar såväl öppna frågor som skattningsfrågor och även möjlighet att ange fria kommentarer.Eleverna uppgav att det är viktigt att genomföra både grundläggande och repeterande SD-utbildning.De värdesatte SD-teori generellt sett och efterfrågade ett mer omfattande och djupare teoretiskt paket än vad de hittills har erhållit.Eleverna ansåg också att utbildningen på AMST på ett effektivt sätt ger en ökad förståelse för illusioner, en ökad förmåga att känna igen en illusion och även att komma över en villa om den skulle inträffa.När det gäller night vision (NV) delen uppgav eleverna att utbildningen på ett effektivt sätt ger en ökad förståelse för problematiken runt flygning med night vision goggles (NVG), en ökad förmåga att känna igen NV-relaterade fenomen och en förberedelse för att kunna hantera flygning med NVG.Eleverna framhöll att kursen i större utsträckning borde ha koordinerats med avseende på tid och innehåll med annan redan genomgången utbildning eller sådan som är inplanerad längre fram.I de fall eleverna redan upplevt en del illusioner eller erfarit NV-fenomen etc. uppfattades utbildningen som ett bra komplement och en repetition.Eleverna ansåg att utbildningen på AMST delvis var ineffektiv och man hade förväntat sig både mer teori och tid i simulatorn.Ett stort antal elever i kombination med begränsad tillgång till simulatorutrustning ledde till en ansenlig väntetid mellan passen.Eleverna ansåg också att det finns möjlighet till förbättringar av den SD-utbildning som ges i stort och avgav ett antal olika förslag.

  • 260.
    Li, Xiaogai
    KTH, School of Technology and Health (STH), Neuronic Engineering.
    Finite Element and Neuroimaging Techniques toImprove Decision-Making in Clinical Neuroscience2012Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Our brain, perhaps the most sophisticated and mysterious part of the human body, to some extent, determines who we are. However, it’s a vulnerable organ. When subjected to an impact, such as a traffic accident or sport, it may lead to traumatic brain injury (TBI) which can have devastating effects for those who suffer the injury. Despite lots of efforts have been put into primary injury prevention, the number of TBIs is still on an unacceptable high level in a global perspective.

    Brain edema is a major neurological complication of moderate and severe TBI, which consists of an abnormal accumulation of fluid within the brain parenchyma. Clinically, local and minor edema may be treated conservatively only by observation, where the treatment of choice usually follows evidence-based practice. In the first study, the gravitational force is suggested to have a significant impact on the pressure of the edema zone in the brain tissue. Thus, the objective of the study was to investigate the significance of head position on edema at the posterior part of the brain using a Finite Element (FE) model. The model revealed that water content (WC) increment at the edema zone remained nearly identical for both supine and prone positions. However, the interstitial fluid pressure (IFP) inside the edema zone decreased around 15% by having the head in a prone position compared with a supine position. The decrease of IFP inside the edema zone by changing patient position from supine to prone has the potential to alleviate the damage to axonal fibers of the central nervous system. These observations suggest that considering the patient’s head position during intensive care and at rehabilitation should be of importance to the treatment of edematous regions in TBI patients.

    In TBI patients with diffuse brain edema, for most severe cases with refractory intracranial hypertension, decompressive craniotomy (DC) is performed as an ultimate therapy. However, a complete consensus on its effectiveness has not been achieved due to the high levels of severe disability and persistent vegetative state found in the patients treated with DC. DC allows expansion of the swollen brain outside the skull, thereby having the potential in reducing the Intracranial Pressure (ICP). However, the treatment causes stretching of the axons and may contribute to the unfavorable outcome of the patients. The second study aimed at quantifying the stretching and WC in the brain tissue due to the neurosurgical intervention to provide more insight into the effects upon such a treatment. A nonlinear registration method was used to quantify the strain. Our analysis showed a substantial increase of the strain level in the brain tissue close to the treated side of DC compared to before the treatment. Also, the WC was related to specific gravity (SG), which in turn was related to the Hounsfield unit (HU) value in the Computerized Tomography (CT) images by a photoelectric correction according to the chemical composition of the brain tissue. The overall WC of brain tissue presented a significant increase after the treatment compared to the condition seen before the treatment. It is suggested that a quantitative model, which characterizes the stretching and WC of the brain tissue both before as well as after DC, may clarify some of the potential problems with such a treatment.

    Diffusion Weighted (DW) Imaging technology provides a noninvasive way to extract axonal fiber tracts in the brain. The aim of the third study, as an extension to the second study was to assess and quantify the axonal deformation (i.e. stretching and shearing)at both the pre- and post-craniotomy periods in order to provide more insight into the mechanical effects on the axonal fibers due to DC.

    Subarachnoid injection of artificial cerebrospinal fluid (CSF) into the CSF system is widely used in neurological practice to gain information on CSF dynamics. Mathematical models are important for a better understanding of the underlying mechanisms. Despite the critical importance of the parameters for accurate modeling, there is a substantial variation in the poroelastic constants used in the literature due to the difficulties in determining material properties of brain tissue. In the fourth study, we developed a Finite Element (FE) model including the whole brain-CSF-skull system to study the CSF dynamics during constant-rate infusion. We investigated the capacity of the current model to predict the steady state of the mean ICP. For transient analysis, rather than accurately fit the infusion curve to the experimental data, we placed more emphasis on studying the influences of each of the poroelastic parameters due to the aforementioned inconsistency in the poroelastic constants for brain tissue. It was found that the value of the specific storage term S_epsilon is the dominant factor that influences the infusion curve, and the drained Young’s modulus E was identified as the dominant parameter second to S_epsilon. Based on the simulated infusion curves from the FE model, Artificial Neural Network (ANN) was used to find an optimized parameter set that best fit the experimental curve. The infusion curves from both the FE simulations and using ANN confirmed the limitation of linear poroelasticity in modeling the transient constant-rate infusion.

    To summarize, the work done in this thesis is to introduce FE Modeling and imaging technologiesincluding CT, DW imaging, and image registration method as a complementarytechnique for clinical diagnosis and treatment of TBI patients. Hopefully, the result mayto some extent improve the understanding of these clinical problems and improve theirmedical treatments.

  • 261. Lidayová, K.
    et al.
    Frimmel, H.
    Wang, Chunliang
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Image Processing and Visualization.
    Bengtsson, E.
    Smedby, Örjan
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Image Processing and Visualization.
    Skeleton-based fast, fully automated generation of vessel tree structure for clinical evaluation of blood vessel systems2017In: Skeletonization: Theory, Methods and Applications, Elsevier, 2017, 345-382 p.Chapter in book (Other academic)
    Abstract [en]

    This chapter focuses on skeleton detection for clinical evaluation of blood vessel systems. In clinical evaluation, there is a need for fast and accurate segmentation algorithms that can reliably provide vessel measurements and additional information for clinicians to decide the diagnosis.Since blood vessels have a characteristic tubular shape, their segmentation can be accelerated and facilitated by first identifying the rough vessel centerlines, which can be seen as a special case of an image skeleton extraction algorithm. A segmentation algorithm will finally use the resulting skeleton as a seed region during the segmentation. The proposed method takes an unprocessed 3D computed tomography angiography (CTA) scan as an input and generates a connected graph of centrally located arterial voxels. The method works in two levels, where large arteries are captured in the first level, and small arteries are added in the second one. Experimental results show that the method can achieve high overlap rate and acceptable detection rate accuracies. High computational efficiency of the method opens the possibility for an interactive clinical use.

  • 262.
    Liljemalm, Rickard
    KTH, School of Technology and Health (STH), Medical Engineering, Neuronic Engineering.
    Infrared Laser Stimulation of Cerebral Cortex Cells - Aspects of Heating and Cellular Responses2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The research of functional stimulation of neural tissue is of great interest within the field of clinical neuroscience to further develop new neural prosthetics. A technique which has gained increased interest during the last couple of years is the stimulation of nervous tissue using infrared laser light. Successful results have been reported, such as stimulation of cells in both the central nervous system, and in the peripheral nervous system, and even cardiomyocytes. So far, the details about the stimulation mechanism have been a question of debate as the mechanism is somewhat hard to explain. The mechanism is believed to have a photo-thermal origin, where the light from the laser is absorbed by water, thus increasing the temperature inside and around the target cell. Despite the mechanism questions, the technique holds several promising features compared to traditional electrical stimulation. Examples of advantages are that it is contact free, no penetration is needed, it has high spatial resolution and no toxic electrochemical byproducts are produced during stimulation. However, since the laser pulses locally increase the temperature of the tissue, there is a risk of heat induced damage. Therefore, the effect of increased temperatures must be investigated thoroughly. One method of examining the changes in temperature during stimulation is to model the heating.

    This thesis is based on the work from four papers with the main aim to investigate and describe the response of heating, caused by laser pulses, on central nervous system cells. In paper one, a model of the heating during pulsed laser stimulation is established and used to describe the dynamic temperature changes occurring during functional stimulation of cerebral cortex cells. The model was used in all four papers. Furthermore, single cell responses, as action potentials, as well as network responses, as activity inhibition, were observed. In paper two, the response of rat astrocytes exposed to laser induced hyperthermia was investigated. Cellular migration was observed and the migration limit was used to calculate the kinetic parameters for the cells, i.e., the reaction activation energy, Ea (321.4 kJmol-1), and the frequency factor, Ac (9.47 x 1048 s-1). Furthermore, a damage signal ratio (DSR) for calculating a threshold for cellular damage was defined, and calculated to six percent. In paper three, the response of hyperthermia to cerebral cortex cells was investigated, in the same way as in the second paper. Fluorescence staining of the metabolic activity was used to reveal the heat response, and by using the limit of the observed increased fluorescence the kinetic parameters, Ea (333.6 kJmol-1), and Ac (9.76 x 1050 s-1), were calculated. The DSR for the cells was calculated to five percent. In paper four, the behavior of action potentials triggered by laser stimulation was investigated. More specifically, the time delay from the start of a laser pulse to the detection of an action potential, delta-t, were investigated. Two different behaviors for the initial action potentials were observed: fast decreasing delta-t and slow decreasing delta-t. The results show the dynamic behavior of action potential responses to infrared light.

    The work of this thesis show the dynamic changes of the temperature during optical stimulation, using an infrared laser working at 1,550 nanometers. It also shows how the changes cause astrocytes to migrate for pulses several seconds long, and neurons to fire action potentials for pulses in the millisecond range. Furthermore, a damage signal ratio was defined and calculated for the cell systems.

  • 263.
    Lind, Carl
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Assessment and design of industrial manual handling to reduce physical ergonomics hazards: – use and development of assessment tools2017Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Despite efforts of reducing harmful physical ergonomics exposures related to manual handling, the occurrence of heavy or repetitive manual handling, and non-neutral postures is high in many occupational sectors. To reduce these exposures, interventions and job design strategies can utilize risk assessment. A need was identified of an observation-based tool which supported occupational health and safety practitioners for assessments of risk factors related to manual handling.

    The aim of this thesis was to explore the use and important usability-related aspects of observation-based assessment tools among professional ergonomists, and to develop new research based assessment and screening tools, to present their scientific basis and to evaluate their reliability and usability. A web-based questionnaire was employed to gain knowledge on the use and usability aspects of risk assessment tools among ergonomists in Sweden. The assessment tools RAMP I and RAMP II were developed in an iterative process, including literature searches, expert group judgments, and with input from more than 80 practitioners. The reliability and usability evaluations included assessments and ratings by practitioners.

    The thesis points to a low use of several internationally spread assessment tools among Swedish ergonomists, and a relatively higher use of tools promoted by the Swedish Work Environment Authority. Several usability-related aspects were identified as important, such as being easy and quick to use, its ability to communicate and visualize the results, and its ability to facilitate improvement measures. The developed tools support assessment of a broad range of risk factors related to manual handling. The thesis supports that assessments with acceptable reliability can be achieved for the majority of items of the two developed tools. The thesis supports that the tools are usable in supporting risk assessments targeting risk factors related to industrial manual handling.

  • 264.
    Lind, Carl
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Forsman, Mikael
    Institute of Environmental Medicine, Karolinska Institutet, Stockholm, SWEDEN.
    Rose, Linda
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Development and evaluation of RAMP I: a practitioner tool for screening for musculoskeletal disorder risk factors in manual handlingManuscript (preprint) (Other academic)
    Abstract [en]

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

  • 265.
    Lind, Carl
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Forsman, Mikael
    Institute of Environmental Medicine, Karolinska Institutet, Stockholm, SWEDEN.
    Rose, Linda
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Development and evaluation of RAMP II: a practitioner’s tool for assessing musculoskeletal disorder risk factors in industrial manual handlingManuscript (preprint) (Other academic)
  • 266.
    Lindahl, Marcus
    et al.
    Uppsala Universitet.
    Ulfvengren, Pernilla
    KTH, School of Industrial Engineering and Management (ITM), Industrial Economics and Management (Dept.), Industrial Work Science.
    Guve, Bertil
    KTH, School of Technology and Health (STH), Centres, Centre for Technology in Medicine and Health, CTMH.
    Pineiro, Erik
    KTH, School of Technology and Health (STH), Centres, Centre for Technology in Medicine and Health, CTMH.
    Clinical Innovation Fellowship: an innovation / education initiative for medtech2010Conference paper (Other academic)
    Abstract [en]

    A new initiative of advanced multidisciplinary training in innovation, highly based on collaboration betweenstakeholders in health care, medical device industry and universities. Key areas of development are; overallprinciples of teaching innovation, accelerated problem based learning, the innovation process as educationand practice, needs in healthcare & medtech industry.This paper presents a Swedish initiative of advanced multidisciplinary training in innovation, which is highly based oncollaboration between stakeholders in health care, medical device industry and universities. The goal of this post-graduate education in clinic-centered innovation is to contribute to the development of a regional medical device cluster, toeducate the health care and medical device innovators and leaders for the future and to develop technical and organizational tools and solutions for the participating clinics.A few years ago some individuals at the Center for Technology, Medicine and Health, CTMH, got in contact with theStanford Biodesign Innovation program. Since the need for collaboration across boundaries and silos had been identified there was almost an instant initiative to try this model in Sweden. A dedicated effort to get funding and buildingresearch capacity started in parallel. A joint project for designing and developing a Swedish variation of the programwas set up.The paper presents examples of an existing innovation research education program at Stanford University and thenthe Swedish initiative that starts in the fall of 2010. Then issues and key areas of interest that have been identified indevelopment of the Swedish initiative are presented.These are; overall principles of teaching innovation, accelerated problem based learning, the innovation processas education and practive, and finally particular needs in Swedish health care and medical technology industry. Animportant difference between the programs at Stanford and Stockholm is the inclusion in the Swedish initiative of theorganizational issues faced by the clinics. These issues are exemplified with leadership and management theoriesidentifying health care as a technology intensive and safety critical socio-technical system. Finally these key areas of interest are then consolidated in designing the overall approach to the Swedish initiative and the curriculum in the fellowsspecialized training.The paper reports findings from an ongoing research project whose aim is to identify obstacles and success factorsfor initiating such an initiative within Swedish university and healthcare structures. The research project also aims toevaluate at least three cycles of the program.

  • 267.
    Lindahl, Martin
    KTH, School of Technology and Health (STH), Structural Biotechnology (Closed 20130701).
    tmRNA to the rescue: Structural motives for the salvage of stalled ribosomes2010In: RNA Biology, ISSN 1547-6286, Vol. 7, no 5, 577-581 p.Article in journal (Other academic)
    Abstract [en]

    During translation, mRNA molecules are incidentally damaged, leaving the ribosome unable to reach or recognize the stop codon and thus stalled with mRNA and a potentially harmful polypeptide product attached to tRNA in the ribosomal P-site. In bacteria, a process called trans-translation has evolved, where a protein-RNA complex (smpB-tmRNA) mimicks the role of aminoacyl charged tRNA in the ribosomal A-site. The ribosome then resumes protein synthesis guided by an mRNA-like portion of the tmRNA which ends with a stop codon and codes for a peptide sequence susceptible to proteolysis, thus allowing the bacteria to salvage stalled ribosomes and degrade ill-defined and potentially harmful protein products. In this article, we will recollect how structural studies have yielded a model for how the pre-translocation stages of trans-translation employing structural mimicry. We will also discuss possible models for

  • 268.
    Lindberg, Frida
    KTH, School of Technology and Health (STH), Medical Engineering.
    Ultrasonic Quantification of Skeletal Muscle Dynamics: Feasibility and Limitations2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Pain and disorders of the human skeletal muscles are one of the most common reasons for medical consultations in the western countries today and there is a great need to improve both the understanding and treatment of several different muscular conditions.

    Techniques describing the muscle function in vivo are often limited by either their invasiveness or lack of spatial resolution. Electromyography (EMG) is the most common approach to assess the skeletal muscle function in vivo, providing information on the neurological input. However, the spatial resolution is in general limited and there are difficulties reaching deep musculature without using invasive needles. Moreover, it does not provide any information about muscle structure or mechanical aspects.

    Quantitative ultrasound techniques have gained interest in the area of skeletal muscles and enables non-invasive and in-vivo insight to the intramuscular activity, through the mechanical response of the activation. However, these techniques are developed and evaluated for cardiovascular applications and there are important considerations to be made when applying these methods in the musculoskeletal field. 

    This thesis is based on the work from four papers with the main focus to investigate and describe some of these considerations in combination with the development of processing and analyzing methods that can be used to describe the physiological characteristics of active muscle tissue.

    In the first paper the accuracy of the Doppler based technique Tissue Velocity Imaging (TVI) was evaluated in a phantom study for very low tissue velocities and the effect of the pulse repetition frequency was considered. The second paper presents a biomechanical model to describe the TVI strain’s dependency on the muscle fiber pennation angle. In the third and fourth papers the intramuscular activity pattern was assessed through the regional tissue deformation by motion mode (M-mode) strain imaging. The activity patterns were analyzed during force regulation and for the effects of fatigue.

    The work of this thesis show promising results for the application of these methods on skeletal muscles and indicate high clinical potential where quantitative ultrasound may be a valuable tool to reach a more multifaceted and comprehensive insight in the musculoskeletal function. However, the methodological considerations are highly important for the optimized application and further evaluation and development of analyzing strategies are needed.

  • 269.
    Lindberg, Frida
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Hedlund, Mattias
    Inst. för Samhällsmedicin och Rehabilitering Sjukgymnastik, Umeå Univeristet.
    Öhberg, Fredrik
    Medicinsk Teknik - FoU, Umeå Univeristet.
    Holtermann, Andreas
    National Research Centre for the Working Environment , Köpenhamn.
    Grönlund, Christer
    Medicinsk Teknik - FoU, Umeå Univeristet.
    Biceps brachii activity pattern during repetitive elbow flexions using ultrasound strain: effect of fatigueManuscript (preprint) (Other academic)
  • 270.
    Lindberg, Frida
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Mårtensson, Mattias
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Aesthetic ultrasound devices: Current state of knowledge and suggested measurement set-up for characterization of exposure2013Report (Other academic)
    Abstract [en]

    This report concerns the ultrasound devices used for the aesthetic purposes of body contouring and fat reduction (ablation of adipose tissue). Such devices have recently become more frequent on the Swedish market. These ultrasound devices are currently not medically regulated in Sweden and little is known about their safety and potentially harmful exposure when using them.

    This report aims to provide relevant information about present guidelines and scientific results in the area, a survey of the Swedish market and also recommendations on how to characterize the ultrasound emitted by these devices. This information provides an important basis for possible future regulatory actions.

    All aesthetic ultrasound devices found on the Swedish market use low-frequency non-thermal ultrasound. These types of devices (with one exception) have not yet been studied in peer-reviewed publications and the technical specifications from the suppliers are often incomplete. Consequently, there is a need to evaluate the devices in order to gain adequate knowledge about possible risks associated with their use.

    Ultrasound exposure should be characterized by its frequency and acoustic pressure. It has not been fully investigated whether the mathematical equation for the mechanical index is valid for the low frequencies used by aesthetic ultrasound equipment on the Swedish market. In this report, two different hydrophone measurement set-ups for characterization of ultrasound exposure are proposed. The most common reason behind adverse events or exposure of non-target tissue regions is most likely handling errors by the operator. Hence, only characterization of the ultrasound field does not necessarily imply the safe use of aesthetic ultrasound devices.

    It is recommended that the Swedish Radiation Safety Authority and the Swedish Medical Products Agency discuss their respective future responsibility and how aesthetic ultrasound devices should be regulated.

  • 271. Lindholm, Peter
    et al.
    Boberg, Olle
    Frånberg, Oskar
    KTH, School of Technology and Health (STH), Environmental Physiology (Closed 20130701).
    Larsson, Åke
    Gullstrand, Lennart
    Intermittent oxygen inhalation increase maximal workload and maximal heart rate in elite athletes2013In: The FASEB Journal, ISSN 0892-6638, E-ISSN 1530-6860, Vol. 27Article in journal (Other academic)
  • 272.
    Lindskog, Pernilla
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Kan lean bli hållbart i svensk sjukvård?: Om betydelsen av delaktighet och tydlighet2014Licentiate thesis, comprehensive summary (Other academic)
    Abstract [en]

    Something is happening within healthcare. An increased pressure for change towards increased efficiency and effectiveness has made Swedish healthcare organizations focusing on organizational change strategies – where expressions such as continuous improvements and to do more with less are frequently used. Lean production (lean) is a commonly used organizational development strategy within Swedish healthcare. However, many organizations today fail when trying to implement lean as a means to change the organization.

    The purpose of this thesis is to increase the knowledge level about sustainable development work and working conditions within Swedish healthcare. Another purpose is to make this knowledge applicable to on-going development work of today.

    In this thesis, the approach has been interactive research, where a method triangulation has been used including a literature study, a qualitative study, and a quantitative study. The empirical data are from two Swedish hospitals.

    By using an interactive research approach, joint learning among the researcher and first-line management within Swedish psychiatric care has been reached. This joint learning concerns how to strengthen the sustainability of organizational development work within Swedish healthcare. Specifically, the findings show that participation, as a democratic principle and an important organizational development factor, needs to be promoted among first-line management in the development work. For the development work to be sustainable, all parties within the organization need to participate in the work.

    Finally, the findings show that clear organizational structures, i.e. objectives and responsibilities, correlate to participation in the organization. The prerequisites for sustainable development work within Swedish healthcare are believed to be strengthened due to the Scandinavian organizational tradition of participation.

  • 273.
    Lindskog, Pernilla
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Organizational Change through Interactive Research or a Consultant’s Intervention: Reflections about pros and cons2011Conference paper (Other academic)
    Abstract [en]

    This abstract is written at the start up of an interactive oriented research project. The author has previous experience as a consultant and is reflecting upon possible differences between being a consultant and being a researcher. In the paper, a reflection is made on possible differences when using an academic or a consultant approach in an organizational intervention.  The consultants are seen as the change agents, fully devoting themselves to the needs of the clients in performing an organizational intervention. The consultant’s role, as being a change agent, is sometimes compared to the role of an action researcher. However, the action researchers should not only satisfy the organizations but should also add critical knowledge to existing research. In interactive research, the emphasis is even larger on the importance of separating the role of a researcher from a developer in order to carefully consider issues of validity. As opposed to the action researcher’s role, an interactive researcher is expected to perform a joint analysis with the involved actors of the organization instead of taking responsibility of the change process. Even so, both interactive and action research can be seen as new production of knowledge in addition to traditional research. The question which is reflected upon is: If there is a difference between the role of a consultant and an action researcher in an organizational intervention, is there really a difference between interactive and action research? Aspects such as participation, learning and sustainability are considered. The empirical data is collected from the author’s involvement in two parallel research projects as an interactive researcher. One project is within the public sector and the other is within the public psychiatric care sector. Both involve change projects aimed towards the development of lean production.

  • 274.
    Lindskog, Pernilla
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Reaching at Sustainable Development: Lean in the Public Sector2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The concept of sustainable development is commonly used worldwide. In the public sector, characterized by a rationalization focus, conclusions about the sustainability of lean production (lean), as a management concept for organizational change, are contradictory. This thesis aims to identify conditions promoting sustainable development in the public sector, in particular the healthcare sector, when implementing lean. Two qualitative and one quantitative case study were conducted using longitudinal data collection: focus group interviews, semi-structured interviews, analysis seminars, steering board meetings, and a questionnaire. The empirical data was collected from national lean programs in Sweden. The results describe that socio-technical principles may be used as indicators of sustainability as well as a guide in the implementation of lean in healthcare. Active ownership among stakeholders, a developmental view in the organization, stakeholder participation, organized joint innovative learning activities, role and goal clarity may be conditions influencing the sustainability of lean in the public sector. Furthermore, when supported by a favorable lean context, the results show that the lean tools value stream mapping, standardized work and 5S (housekeeping) may promote a sustainable implementation of lean in healthcare by the promotion of employees and managers’ working conditions and/or employee individual innovation. Visual follow-up boards may inhibit employees and managers’ job satisfaction, when not supported by job resources. Personnel stability, time for development, and information to be able to participate were in this context shown to be central job resources. In conclusion, conditions which may promote sustainable development in the public sector, when implementing lean are: stakeholder values of inclusive social well-being, an implementation process including stakeholder ownership and joint innovative learning, and a favorable lean context: balancing job resources and job demands. Lean tools may empower public healthcare employees to engage in development and counteract a poor implementation process and a poor lean context but only to a limited degree. The lean contexts studied were unfavorable, i.e., a weak implementation process and job resources not balancing the job demands. Hence, the lean implementations studied could not be considered sustainable.

  • 275.
    Lindskog, Pernilla
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Halvarsson, Agneta
    APeL FoU, Örebro, Sweden.
    Brännmark, Mikael
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Sustainable Development Work (Lean) in Swedish Healthcare: A longitudinal and quantitative study concerning effects of goal settings on participation2013Conference paper (Other academic)
  • 276.
    Lindskog, Pernilla
    et al.
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Vänje, Annika
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Brännmark, Mikael
    KTH, School of Technology and Health (STH), Health Systems Engineering, Ergonomics.
    Törnkvist, Åsa
    Uppsala University Hospital.
    Managerial Challenges in Creating Sustainable Development Work (Lean): An interactive case study from socio-technical perspectivesManuscript (preprint) (Other academic)
    Abstract [en]

    Purpose - At present, healthcare organizations are facing both quality and financial challenges. Consequently, organizations in this sector have started to introduce Lean inspired production concepts in order to become more efficient and effective. The implementation of Lean in healthcare is not unproblematic, especially not within psychiatry, the context of which differs greatly from other sectors where it is more usual to see Lean implemented. The aim of this article is to identify managerial preconditions for the implementation of a sustainable Lean organization at a psychiatry division in a Swedish university hospital.

    Design/methodology/approach – An interactive case study approach was chosen with the purpose of gaining deeper knowledge and understanding of the first-line managers’ role during implementation of Lean. Focus group interviews together with 24 first-line managers were conducted. In the analysis, a socio-technical perspective was used due to the characteristics of the psychiatry healthcare context but also from a sustainability perspective. The empirical data from the focus group interviews were also complemented with a semi-structured interview with a key actor.

    Findings – Development work is context dependent and so is the implementation of Lean. This particular case study points out that clarity of the organizational structures within the Lean work, i.e. objectives and roles, affects the level of participation and consequently the sustainability of the Lean implementation. The empirical findings also show that a managerial lack of power and authority make it difficult for first-line managers (the majority being nurses) to prioritize engagement and time spent in Lean work.

    Originality/value – At present there are few studies on the implementation of Lean within the psychiatry healthcare sector and in a socio-technical context. In this article a model is presented, visualizing managerial preconditions for sustainable Lean in the context presented.

  • 277.
    Liu, Xuejin
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Characterization and Energy Calibration of a Silicon-Strip Detector for Photon-Counting Spectral Computed Tomography2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Multibin photon-counting x-ray detectors are promising candidates to be applied in next generation computed tomography (CT), whereby energy information from a broad x-ray spectrum can be extracted and properly used for improving image quality and correspondingly reducing radiation dose. A silicon-strip detector has been developed for spectral CT, which operates in photon-counting mode and allows pulse-height discrimination with 8 adjustable energy bins.

    Critical characteristics, energy resolution and count-rate performance, of the detector are evaluated. An absolute energy resolution (E) from 1.5 keV to 1.9 keV with increasing x-ray energy from 40 keV to 120 keV is found. Pulse pileup degrades the energy resolution by 0.4 keV when increasing the input count rate from zero to 100 Mcps mm−2, while charge sharing shows negligible effect. A near linear relationship between the input and output count rates is observed up to 90 Mcps mm−2 in a clinical CT environment. In addition, no saturation effect appears for the maximally achieved photon flux of 485 Mphotons s−1 mm−2 with a count rate loss of 30%.

    The detector is energy calibrated in terms of gain and offset with the aid of monoenergetic x rays. The gain variation among channels is below 4%, whereas the variation of offsets is on the order of 1 keV. In order to do the energy calibration in a routinely available way, a method that makes use of the broad x-ray spectrum instead of using monoenergetic x rays is proposed. It is based on a regression analysis that adjusts a modelled spectrum of deposited energies to a measured pulse-height spectrum. Application of this method shows high potential to be applied in an existing CT scanner with an uncertainty of a calibrated threshold between 0.1 and 0.2 keV.

    The energy-calibration method is further used in the development of a spectral response model of the detector. This model is used to accurately bin-wise predict the response of each detector channel, which is validated by two application examples. First, the model is used in combination with the inhomogeneity compensation method to eliminate ring artefacts in CT images. Second, the spectral response model is used as the basis of the maximum likelihood approach for projection-based material decomposition. The reconstructed basis images show a good separation between the calcium-like material and the contrast agents, iodine and gadolinium. Additionally, the contrast agent concentrations are reconstructed with more than 94% accuracy.

  • 278. Ljungblad, C.
    et al.
    Granström, F.
    Dellve, Lotta
    KTH, School of Technology and Health (STH), Ergonomics.
    Åkerlind, I.
    Associations between workplace health promotion and employee health in 60 municipal social care organizations in Sweden 20082012In: European Journal of Public Health, ISSN 1101-1262, E-ISSN 1464-360X, Vol. 22, 28-29 p.Article in journal (Other academic)
  • 279.
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Accessibility to Home and Environment2013In: Towards Accessibility City: Seminar on collaboration between Sweden and Kuala Lumpur, 2013Conference paper (Other academic)
  • 280.
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    ACTION - ett anhörigstöd: Testat i Linköpings kommun under 2 år2009Report (Other academic)
    Abstract [sv]

    Behovet av ljus ökar med stigande ålder och bristande belysning kan vara en orsak till att särskilt äldre människor snubblar och faller med skador som följd. Linköpings kommun har genomfört en belysningsstudie bland dagens äldre i Linköping vars syfte varit att få kunskap om vilka behov av åtgärder kring belysning som finns hos de äldre. Studien har finansierats inom ramen för programmet Teknik för äldre som administreras av Hjälpmedelsinstitutet på uppdrag av Socialdepartementet.

    Ögat förändras under åldrandeprocessen och redan i 40-års åldern kan man märka hur synen blivit sämre än den var vid yngre år. En person i 40-års åldern behöver dubbelt så mycket ljus som en person i 20-års åldern för att kunna läsa eller skriva. För äldre kan också ljus i form av ljusterapi ha en mycket god effekt på sömn och välbefinnande. Frågan om belysning är därför starkt relaterad till ålder. Marknaden för belysning utvecklas idag i rask takt. Ny teknik att skapa ljus i form av lågenergilampor eller lysdioder (LED) bidrar till denna utveckling.

    Rapporten presenterar hur de intervjuades belysningsförhållanden ser ut idag och vilka problem eller önskemål de intervjuade upplever kring belysning i bostaden.

    Men belysningen i äldres hem har inte bara betydelse för deras egen hälsa och välmående. I takt med att allt fler får vård och omvårdnad i sina bostäder blir bostaden också en arbetsplats för dem som ger vården. Det blir en balansgång mellan att undvika att bostaden utrustas och upplevs som en vårdplats, och att ge dem som vårdar den äldre i bostaden goda arbetsvillkor.

    Resultatet av intervjuerna som gjordes både som strukturerade intervjuer och som djupintervjuer samt med okulär besiktning av bostäderna, visar att de intervjuade oftast har alldeles för svag belysning. Särskilt visar det sig i sådana utrymmen där risken för fallskador är störst. I hallen och i vardagsrummet är belysningen oftast mycket bristfällig. I hallen för att det inte finns så många möjligheter att installera ljus eftersom det traditionellt finns ett takuttag där det oftast sitter en plafond med alldeles för svag glödlampa. På väggarna finns oftast bara ett eluttag som används till spegelbelysning eller dekorativ belysning.

    Ett annat problem utgörs av svårigheterna att byta glödlampor i taket. De äldre vågar inte ställa sig på pallar eller stegar för att byta glödlampor, eftersom de ofta har problem med balansen. Likaså är sladdar på golvet ett återkommande problem.

  • 281.
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Digitala larmsystemets möjligheter och hinder2014In: Samverkan för Hälsa, Vård och Omsorg, 2014Conference paper (Other academic)
  • 282.
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Digitala lås2010Report (Other academic)
    Abstract [sv]

    Sammanfattning

    Användningen av elektroniska lås har på allvar börjat bli en fråga som fler och fler, både fastighets- och vårdföretag, tar upp. De risker som är förknippade med att hantera andras nycklar vill både vårdgivare och bostadsinnehavare minimera. Hjälpmedelsinstitutet har inom ramen för regeringsuppdraget Teknik för äldre finansierat denna test av elektroniska lås som genomförts i det lab som Centrum för Hälsa och Byggande (CHB) på KTH i Handen har satt upp. Syftet med testet har varit att se hur de elektroniska lås som finns på den svenska marknaden idag fungerar. Och hur de motsvarar krav som kan ställas inom äldreomsorg och vård i hemmet.

    I den här testen har fyra lås från olika tillverkare testats medan fem har identifierats. Det femte kommer att testas inom kort i CHBs lab där för övrigt planen är att alla nya elektroniska lås som kommer ut på marknaden fortlöpande testas och publiceras på CHBs hemsida (www.chb.kth.se).

    Resultaten visar att det finns i huvudsak två huvudkategorier av elektroniska lås, eller lås med digitala nycklar. Den ena innebär ett fast installerat lås som är anslutet till någon form av box i bostaden och som kan kommunicera med en central via Internet. Det är en lösning som också erbjuder en hel del tilläggstjänster som kan underlätta kvarboende för den som är äldre. Den andra lösningen är mobil i det avseendet att låset kan installeras och nedmonteras för att flyttas till en annan vårdkund mycket snabbt. Det är ett lås som inte själv är kopplat till Internet eller annat nätverk, utan kommunikationen med låset sker via den digitala nyckeln eller genom att man själv går till låset och hämtar information om det behövs.

    Det är viktigt att påpeka att Datainspektionen har beskrivit vilka krav som ställs på ett digitalt lås som används hos en boende. Bland annat måste den boende vara informerad om låset och loggar får inte sparas hur länge som helst.

    Endast en låstillverkare har idag redovisat att det finns möjlighet att ansluta deras lås till ett administrativt system som kan användas av vårdgivaren, men det finns en beredskap att ta fram det gränssnitt som är nödvändigt för att detta ska vara möjligt, hos de andra tillverkarna. Det krävs dock att det finns en efterfrågan av detta.

  • 283.
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB. KTH, School of Technology and Health (STH), Design, Work Environment, Safety and Health, DASH.
    Facilities Management and Health Care at Home2007Doctoral thesis, comprehensive summary (Other scientific)
    Abstract [en]

    The topic of this thesis is the new requirements that will be put upon the facilities management when the elderly are living longer in their own homes, in spite of illness, impairment and old age. For many reasons, especially demographic ones, this issue has come to the fore and since it has substantial political impact and considerably affects our living conditions, it will most certainly appear on the agenda of most Swedish housing companies in the near future.

    The growing number of inhabitants in need of care and rehabilitation is a current subject in many countries of the industrial world. More medical conditions can be treated, but often at an ever increasing cost. Care and housing are often interlinked and more interest is being paid to the possibility of offering care to elderly in their own homes.

    This development must lead to a discussion of the home as a hospital ward from time to time, and the demands it places on facilities management and security. So far the prospects of telecare services and "Smart homes" has been very little discussed in parallel, although in many aspects they share the same technological base.

    The principal interest of the housing companies is to find a role in accordance with their mainstream business, and at the same time co-operate with other municipal actors directly in charge of offering assistance and service. There has been only limited study and research into the complex interaction between technology, home-based social service and the housing company.

    The purpose here is to develop an understanding of the requirements placed on both the housing company and the CP when a tenant is to be subjected to minor and more extensive care at home, or suffers from an illness or an impairment which requires special equipment or technical adjustment in the home. A model to interpret this situation has been developed in this thesis.

  • 284.
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    IT i hemmet för vård och omsorg2006Report (Other academic)
    Abstract [sv]

    Människor lever allt längre och är aktiva upp i hög ålder. För kommunernas del sker en anpassning som betyder en omfördelning av resurser från ”unga” gamla till ”äldre” gamla. Färre får omsorg i särskilt boende och fler i det ordinära boendet i form av hemtjänst och annan avlastning. De äldre som ändå flyttar till särskilt boende är i så stort behov av omsorg att de inte längre kan bo kvar hemma.

    Utvecklingen inom vården gör att bostaden blir platsen för allt mer av vård och omsorg – exempelvis skickas människor hem allt tidigare efter operationer vilket betyder att eftervården förläggs till den egna bostaden. När bostaden blir så central för vård och omsorg finns det också anledning att undersöka hur fastighetsförvaltningen utvecklas för att se om dess utvecklingslinje möter vårdens eller kanske divergerar. En stor del av de äldre drabbas av kognitiva funktionsnedsättningar till följd av sjukdomar eller som en följd av åldrandet.

    Personer med kognitiva funktionsnedsättningar har ofta svårigheter att minnas, orientera sig i tid och rum samt försämrad problemlösningsförmåga. Det kan leda till stora problem för brukaren och ställer stora krav på omgivningen. Samtidigt är strävan att klara sig själv en av de starkaste drivkrafterna för alla människor. Utformat och använt på rätt sätt kan tekniskt stöd vara ett bra komplement eller till och med möjliggöra ett självständigt boende för många personer som i dag är i behov av hjälp från utomstående[1].

    Minnesstöd och orienteringshjälpmedel är därför ett område där tekniken kan bidra på ett naturligt sätt utan att ersätta mänskliga kontakter. Istället kan det skapa självständighet och ökad självsäkerhet för den som drabbats av kognitiva problem. Andra områden där tekniken kan bidra är kring säkerhet och trygghet.

  • 285.
    Lundberg, Stefan
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Omsorg och vård i bostaden: krav på infrastruktur nu och i framtiden2008Report (Other academic)
    Abstract [sv]

    Det finns behov av att kunna bedöma vilka krav framtida omsorg och vård kan komma att ställa på bostadens infrastruktur. Intresseorganisationer som SABO och Fastighetsägareförbundet tillsammans med aktörer inom byggindustrin är just nu i full färd med att ta fram rekommendationer för hur de så kallade hemmanäten för bostäder bör se ut. Den här rapporten är ett bidrag till underlaget för det arbetet utifrån några samhällstjänster.

    Trender kring omsorg och vård i hemmet har här studerats i ett antal nationella rapporter och internationella artiklar. Resultatet visar att både omsorgsverksamheten och vården arbetar med att ta fram system som ska göra arbetet i mobila team smidigare och enklare. Det är främst administrativa system kring journaler och processer som man försöker göra tillgängliga både över ansvarsgränserna landsting – kommun, men även i mobila system som team kan ha med sig överallt. Bild- eller videoöverföring från en bostad till en centralt placerad expert för råd och anvisningar är ett sådant exempel i framkanten på utvecklingen. Likaså icke-invasiva mätsystem i kläder som underlättar för patientens egenvård är ett annat. Vården tenderar att utveckla system som är oberoende av bostadens både el- och telefonnät. Istället baseras de på mobiltelefoni och batterisäkerhet. Det som kommer att ställa krav på bostädernas infrastruktur är lokala nätverk med sensorer och signaler för att skapa varnings- och påminnelsesystem hos den som behöver ett minnesstöd till exempel. Det vill säga sådana system som omsorgen arbetar med för att förlänga och underlätta äldres kvarboende i den egna bostaden. Sådana nätverk kan mycket väl vara samutnyttjade med fastighetens eget behov av telemetrisystem för mätning av energiförbrukning och för att eventuellt erbjuda andra bekvämlighetstjänster till den boende. En annan typ av tjänst som troligen kommer att växa är kommunikation via bild. Det förekommer både inom vården och inom omsorg eller anhörigvård. Kravet på tillräcklig bandbredd på framtidens IPTV kommer därmed att vara stort.

  • 286.
    Lundberg, Stefan
    et al.
    KTH, School of Technology and Health (STH), Centres, Centre for Health and Building, CHB.
    Olofsson, Ann-Britt
    Linköpings kommun.
    Belysning i Bostaden2009Report (Other academic)
    Abstract [sv]

    Behovet av ljus ökar med stigande ålder och bristande belysning kan vara en orsak till att särskilt äldre människor snubblar och faller med skador som följd. Linköpings kommun har genomfört en belysningsstudie bland dagens äldre i Linköping vars syfte varit att få kunskap om vilka behov av åtgärder kring belysning som finns hos de äldre. Studien har finansierats inom ramen för programmet Teknik för äldre som administreras av Hjälpmedelsinstitutet på uppdrag av Socialdepartementet.

    Ögat förändras under åldrandeprocessen och redan i 40

    -års åldern kan man märka hur synen blivit sämre än den var vid yngre år. En person i 40-års åldern behöver dubbelt så mycket ljus som en person i 20-

    års åldern för att kunna läsa eller skriva. För äldre kan också ljus i form av ljusterapi ha en mycket god effekt på sömn och välbefinnande. Frågan om belysning är därför starkt relaterad till ålder. Marknaden för belysning utvecklas idag i rask takt. Ny teknik att skapa ljus i form av lågenergilampor eller lysdioder (LED) bidrar till denna utveckling.

    Rapporten presenterar hur de intervjuades belysningsförhållanden ser ut idag och vilka problem eller önskemål de intervjuade upplever kring belysning i bostaden.

    Men belysningen i äldres hem har inte bara betydelse för deras egen hälsa och välmående. I takt med att allt fler får vård och omvårdnad i sina bostäder blir bostaden också en arbetsplats för dem som ger vården. Det blir en balansgång mellan att undvika att bostaden utrustas och upplevs som en vårdplats, och att ge dem som vårdar den äldre i bostaden goda arbetsvillkor.

    Resultatet av intervjuerna som gjordes både som strukturerade intervjuer och som djupintervjuer samt med okulär besiktning av bostäderna, visar att de intervjuade oftast har alldeles för svag belysning. Särskilt visar det sig i sådana utrymmen där risken för fallskador är störst. I hallen och i vardagsrummet är belysningen oftast mycket bristfällig. I hallen för att det inte finns så många möjligheter att installera ljus eftersom det traditionellt finns ett takuttag där det oftast sitter en plafond med alldeles för svag glödlampa. På väggarna finns oftast bara ett eluttag som används till spegelbelysning eller dekorativ belysning.

    Ett annat problem utgörs av svårigheterna att byta glödlampor i taket. De äldre vågar inte ställa sig på pallar eller stegar för att byta glödlampor, eftersom de ofta har problem med balansen. Likaså är sladdar på golvet ett återkommande problem.

     

  • 287.
    Lundqvist, Joakim
    et al.
    Dept. of Molecular Biophysics, Lund University.
    Elmlund, Hans
    KTH, School of Technology and Health (STH), Structural Biotechnology.
    Kasperska, Dominika
    Division of Metabolic Diseases, Karolinska Institutet.
    Axelsson, Eva
    Dept. of Biochemistry, Lund University.
    Sirijovski, Nick
    Dept. of Biochemistry, Lund University.
    Hebert, Hans
    KTH, School of Technology and Health (STH), Structural Biotechnology.
    Willows, Robert
    Department of Chemistry and Biomolecular Sciences, Macquarie University.
    Hansson, Mats
    Dept. of Biochemistry, Lund University.
    Lindahl, Martin
    KTH, School of Technology and Health (STH), Structural Biotechnology.
    Al-Karadaghi, Salam
    Dept. of Molecular Biophysics, Lund University.
    Cryo-electron microscopy reveals an ATP-fueled and Integrin-I mediated conformational transition of the AAA+ activation complex in R. capsulatus Mg-chelataseManuscript (Other academic)
  • 288.
    Maksuti, Elira
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Imaging and modeling the cardiovascular system2016Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Understanding cardiac pumping function is crucial to guiding diagnosis, predicting outcomes of interventions, and designing medical devices that interact with the cardiovascular system.  Computer simulations of hemodynamics can show how the complex cardiovascular system is influenced by changes in single or multiple parameters and can be used to test clinical hypotheses. In addition, methods for the quantification of important markers such as elevated arterial stiffness would help reduce the morbidity and mortality related to cardiovascular disease.

    The general aim of this thesis work was to improve understanding of cardiovascular physiology and develop new methods for assisting clinicians during diagnosis and follow-up of treatment in cardiovascular disease. Both computer simulations and medical imaging were used to reach this goal.

    In the first study, a cardiac model based on piston-like motions of the atrioventricular plane was developed. In the second study, the presence of the anatomical basis needed to generate hydraulic forces during diastole was assessed in heathy volunteers. In the third study, a previously validated lumped-parameter model was used to quantify the contribution of arterial and cardiac changes to blood pressure during aging. In the fourth study, in-house software that measures arterial stiffness by ultrasound shear wave elastography (SWE) was developed and validated against mechanical testing.

    The studies showed that longitudinal movements of the atrioventricular plane can well explain cardiac pumping and that the macroscopic geometry of the heart enables the generation of hydraulic forces that aid ventricular filling. Additionally, simulations showed that structural changes in both the heart and the arterial system contribute to the progression of blood pressure with age. Finally, the SWE technique was validated to accurately measure stiffness in arterial phantoms.

  • 289.
    Maksuti, Elira
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Carlsson, Marcus
    Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden..
    Arheden, Håkan
    Lund University, Skane University Hospital, Department of Clinical Sciences Lund, Clinical Physiology, Lund, Sweden..
    Kovács, Sándor J.
    Department of Internal Medicine, Cardiovascular Division, Washington University School of Medicine, St. Louis, Missouri, USA..
    Broomé, Michael
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Ugander, Martin
    Department of Clinical Physiology, Karolinska Institutet, and Karolinska University Hospital, Stockholm, Sweden..
    Hydraulic forces contribute to left ventricular diastolic filling2016Manuscript (preprint) (Other academic)
    Abstract [en]

    Myocardial active relaxation and restoring forces are known determinants of left ventricular (LV) diastolic function. We hypothesize the existence of an additional mechanism involved in LV filling, namely, a hydraulic force contributing to the longitudinal motion of the atrioventricular (AV) plane. A prerequisite for the presence of a net hydraulic force during diastole is that the atrial short-axis area (ASA) is smaller than the ventricular short-axis area (VSA). We aimed (a) to illustrate this mechanism in an analogous physical model, (b) to measure the ASA and VSA throughout the cardiac cycle in healthy volunteers using cardiovascular magnetic resonance imaging, and (c) to calculate the magnitude of the hydraulic force. The physical model illustrated that the anatomical difference between ASA and VSA provides the basis for generating a hydraulic force during diastole. In volunteers, VSA was greater than ASA during 75-100% of diastole. The hydraulic force was the same order of magnitude as the peak driving force of LV (1-3N vs 5-10N). Hydraulic forces are a consequence of left heart anatomy and aid LV diastolic filling. These findings suggest that the relationship between ASA and VSA, and the resulting hydraulic forces, should be considered when characterizing diastolic function and dysfunction. 

  • 290.
    Maksuti, Elira
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Johnson, Jonas
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Bjällmark, Anna
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Broomé, Michael
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging. Karolinska Institutet Department of Physiology and Pharmacology.
    Physical modeling of the heart with the atrioventricular plane as a piston unit2013Conference paper (Other academic)
    Abstract [en]

    Cardiac models do not often take the atrioventricular (AV) interactioninto account, even though medicalimaging and clinical studies have shown that the heart pumps with minorouter volume changes throughout the cardiac cycle and with backand forthlongitudinal movements in the AVregion. We present a novel cardiac model based on physical modeling of the heart withthe AV-plane asa piston unit. Model simulationsgeneratedrealistic outputsforpressures and flows as well asAV-piston velocity, emphasizing the relevance of myocardial longitudinal movements in cardiac function

  • 291.
    Manouras, Aristomenis
    KTH, School of Technology and Health (STH), Medical Engineering.
    Tissue Doppler in Spectral and Color ModeMethodological ConsiderationsNon-invasive Estimation of Left Ventricular Filling Pressures using the E/Em index2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Aims: Tissue Doppler (TD) in spectral mode (spectral TD) and color TD are the two modalities available today in tissue velocity echocardiography (TVE). Measurements of left ventricular (LV) myocardial velocities and displacement may yield different results depending on the employed sonographic modality and the subjective adjustments during data analysis. The ratio of transmitral early diastolic velocity (E) to early diastolic myocardial velocity (Em) has been suggested as a non-invasive estimate of LV filling pressures. The present studies aimed to evaluate the compatibility between the two TD modalities and the effect of temporal filtering and offline gain on velocity and displacement measurements obtained using these two methods. The validity of E/Em in identifying elevated LV filling pressures after acute reductions in hemodynamic LV loading was assessed.

    Methods and Results: In 57 patients, longitudinal myocardial velocity profiles were acquired from the basal LV segments, using spectral and color TD. Peak systolic (Sm) and early diastolic (Em) myocardial velocities and the myocardial displacement during the ejection phase were measured offline. Spectral TD measurements were performed using three different gain settings (0%-, 50%- 100% offline gain). Color TD analysis were performed before and after the application of temporal filtering at 30, 50 and 70 ms filter width. The E/Em ratio was calculated at the different settings. The correlation between spectral- and color TD measurements was good. Changes in offline gain and filter width resulted in significant alterations on spectral and color TD derived measurements, respectively. Sm and Em were significantly higher (p < 0.001) whereas the E/Em was significantly lower (p < 0.001) for measurements performed with spectral TD compared to color TD and the discrepancy among the measurements increased at increasing filter width and gain level. In Study II the results of spectral- and color TD derived displacement were compared to anatomic M-mode. Spectral TD at different gain settings significantly overestimated M-mode derived displacement measurements, whereas the concordance between color TD and M-mode was considerably better.

    In Study III, LV longitudinal systolic myocardial velocities and displacement during ejection period were quantified at the basal septal and lateral wall in 24 healthy individuals using spectral TD, color TD and M-mode. Mean spectral TD systolic velocity and displacement values were obtained from the outer and inner borders of the spectral velocity signal. The estimated mean spectral TD systolic myocardial velocities were highly concordant with corresponding color TD measurements (mean difference 0.1 ± 0.6 cm/s, septal wall; 0.1 ± 1.0 cm/s, lateral wall). Similarly, myocardial displacement obtained by integration over time of mean spectral TD velocities was in good agreement with color TD (mean difference 0.2 ± 0.7 mm, septal wall; 0.02 ± 0.86 mm, lateral wall) as well as with the corresponding M-mode measurements.

    In Study IV, simultaneous LV catheterization and echocardiographic examination was performed in 68 consecutive patients referred for coronary angiography. Doppler signals of the transmitral flow and spectral TD signals at the level of mitral annulus were obtained and the E/Em was then calculated. All examinations were repeated after nitroglycerin (NTG) infusion. At baseline, the predictive ability of E/Em in identifying elevated LVDP was modest at best (area under curve [AUC] ± SE = 0.71 ± 0.08, p < 0.01). The index was more strongly associated with LVDP in patients with reduced ejection fraction (EF) < 55% (r = 0.68; p < 0.01) compared to patients with EF ≥ 55%(r = 0.4; p < 0.05). Following NTG administration, the diagnostic ability of E/Em in detecting elevated LVDP was significantly reduced (area under curve [AUC] ± SE =0.6 ± 0.08, p > 0.05). Changes in LVDP were not reliably tracked using E/Em (p > 0.05).

    Conclusions: Spectral TD yields significantly higher myocardial velocity and displacement values and lower E/Em compared to color TD modality. Increasing gain and temporal smoothing significantly alters the obtained velocity and displacement information and yield greater disparity between measurements derived using the two TD methods. Spectral TD significantly overestimates myocardial displacement obtained using M-mode. On the other hand, the agreement between color TD and anatomic M-mode is considerably better. Measurements based on mean spectral TD velocities were highly concordant with those provided by color TD and M-mode. However, unfavorable limits of agreement discourage the interchangeable use of these modalities. The diagnostic ability of E/Em was poor and declined significantly following acute reduction in LV hemodynamic loading. Changes in LVDP were not predicted by alterations in E/Em. Our findings imply that E/Em might not be sufficiently robust to be employed as a single non-invasive estimate for tailoring medical therapy in patients with elevated LVDP.

  • 292.
    Manouras, Aristomenis
    et al.
    KTH, School of Technology and Health (STH), Medical Engineering.
    Nyktari, Evangelia
    Sahlén, Anders
    Winter, Reidar
    Vardas, Panagiotis
    Brodin, Lars-Åke
    KTH, School of Technology and Health (STH), Medical Engineering.
    The value of E/Em ratio in the estimation of left ventricular filling pressures: impact of acute hemodynamic load reductionManuscript (preprint) (Other academic)
  • 293.
    Marquez Ruiz, Juan Carlos
    KTH, School of Technology and Health (STH), Medical sensors, signals and systems (MSSS) (Closed 20130701).
    Sensor-Based Garments that Enable the Use of Bioimpedance Technology: Towards PersonalizedHealthcare Monitoring.2013Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Functional garments for physiological sensing purposes have been utilized in several disciplinesi.e. sports, firefighting, military and medical. In most of the cases textile electrodes (Textrodes)embedded in the garment are employed to monitor vital signs and other physiologicalmeasurements. Electrical Bioimpedance (EBI) is a non-invasive and effective technology that canbe used for detection and supervision of different health conditions. In some specific applicationssuch as body composition assessment EBIS has shown encouraging results proving good degreeof effectiveness and reliability. In a similar way Impedance Cardiography (ICG) is anothermodality of EBI primarily concerned with the determination of Stroke Volume SV, indices ofcontractility, and other aspects of hemodynamics.EBI technology in the previously mentioned modalities can benefit from a integration with agarment; however, a successful implementation of EBI technology depends on the goodperformance of textile electrodes. The main weakness of Textrodes is a deficient skin-electrodeinterface which produces a high degree of sensitivity to signal disturbances. This sensitivity canbe reduced with a suitable selection of the electrode material and an intelligent and ergonomicgarment design that ensures an effective skin-electrode contact area.This research work studies the performance of textile electrodes and garments for EBIspectroscopy for Total Body Assessment and Transthoracic Electrical Bioimpedance (TEB) forcardio monitoring. Their performance is analyzed based on impedance spectra, estimation ofparameters, influence of electrode polarization impedance Zep and quality of the signals using asreference Ag/AgCl electrodes. The study includes the analysis of some characteristics of thetextile electrodes such as conductive material, skin-electrode contact area size and fabricconstruction.The results obtained in this research work present evidence that textile garments with a dry skinelectrodeinterface like the ones used in research produce reliable EBI measurements in bothmodalities: BIS for Total Body Assessment and TEB for Impedance Cardiography. Textiletechnology, if successfully integrated, may enable the utilization of EBI in both modalities andconsequently implementing wearable applications for home and personal health monitoring.

  • 294. Mekjavic, I. B.
    et al.
    McDonnell, A. C.
    Keramidas, Michail E.
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Environmental Physiology.
    Kolegard, Roger
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Environmental Physiology.
    Lind, Britta
    KTH, School of Technology and Health (STH), Medical Engineering, Medical Imaging.
    Eiken, Ola
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Environmental Physiology.
    Lunar habitat simulation2013Conference paper (Other academic)
  • 295. Mekjavic, Igor
    et al.
    Eiken, Ola
    KTH, School of Technology and Health (STH), Environmental Physiology.
    Lunar Habitat Simulation: Workshop on Bedrest in Hypoxic Environments2010Report (Other academic)
  • 296. Morrison, S. A.
    et al.
    Mirnik, D.
    Korsic, S.
    Eiken, Ola
    KTH, School of Technology and Health (STH), Basic Science and Biomedicine, Environmental Physiology.
    Mekjavic, I. B.
    Groselj, L. Dolenc
    Planetary habitat simulation: interactions between bedrest, hypoxia and confinement on sleep and breathing2014In: Journal of Sleep Research, ISSN 0962-1105, E-ISSN 1365-2869, Vol. 23, 196-196 p.Article in journal (Other academic)
  • 297.
    Moustafa, Ahmed
    et al.
    KTH, School of Technology and Health (STH).
    Hamid Muhammed, Hamed
    KTH, School of Technology and Health (STH), Informatics, logistics and management (Closed 20130701).
    Hassan, Moustapha
    Karolinska Institutet.
    Skin Cancer Detection by Temperature Variation Analysis2012Conference paper (Other academic)
  • 298.
    Myhren, Jonn Are
    KTH, School of Technology and Health (STH), Fluid and Climate Technology.
    Low temperature heating in exhaust ventilated rooms: An approach using Computational Fluid Dynamics2008Licentiate thesis, comprehensive summary (Other scientific)
  • 299.
    Myhren, Jonn Are
    et al.
    KTH, School of Technology and Health (STH), Fluid and Climate Technology.
    Holmberg, Sture
    KTH, School of Technology and Health (STH), Fluid and Climate Technology.
    Comfort temperatures and operative temperatures in an office with different heating methods2006In: Proceedings of the Healthy Buildings Conference: Vol. 2: Indoor Climate, 2006, Vol. 2, 47-52 p.Conference paper (Other academic)
  • 300.
    Myhren, Jonn Are
    et al.
    KTH, School of Technology and Health (STH), Fluid and Climate Technology.
    Holmberg, Sture
    KTH, School of Technology and Health (STH), Fluid and Climate Technology.
    Energy savings and thermal comfort with ventilation radiators: a dynamic heating and ventilation system2007In: Proceedings of Clima 2007 WellBeing Indoors, 2007Conference paper (Other academic)
    Abstract [en]

    Studies indicate that a high ventilation rate with fresh air supply directly from outdoors gives better thermal comfort conditions, less SBS (Sick Building Syndrome) symptoms and increased work productivity. The drawbacks with a high ventilation rate in natural or exhaust ventilated buildings are normally increased energy use for heating and cold air draught. Such problems may be minimized with ventilation radiators, radiators where cold ventilation air is brought directly from outdoors through a wall channel into the radiator where it is heated before entering the room.

    This paper discusses advantages with ventilation radiators in comparison to those of traditional heating systems. Focus has been on energy aspects and thermal comfort. The main conclusions are that ventilation radiators may give a stable and uniform thermal indoor climate. The high thermal gradient between cold ventilation air and the radiator surface inside the ventilation channel also makes the ventilation radiator more efficient than other systems. A method to vary indoor climate on a daily basis according to where people stay is proposed for additional energy savings with ventilation radiators. The deductions were based on results from CFD simulations in a well validated office model.

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