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  • Public defence: 2018-04-27 09:00 Belladonna, Entrance 78, Linköping
    Chang, You
    Linköping University, Department of Clinical and Experimental Medicine, Division of Speech language pathology, Audiology and Otorhinolaryngology. Linköping University, Faculty of Medicine and Health Sciences.
    A Finite Element Model of the Human Head for Simulation of Bone-conducted Sound2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Bone conduction is usually understood as the hearing sensation based on the vibrations of the skull bone and surrounding tissues. The fact that vibration of the skull bones can result in a sound percept has been known for a long time. However, it is difficult to give a general definition of BC sound. Normally, BC sound is described as the sound energy transmitted through the body (comprising the solid and fluid parts) then the outer, middle and inner ear are involved and finally produce a perception of sound.

    Even if BC sound perception has been studied for more than a century, the whole pattern of BC sound transmission is still not complete. There are limitations for experimental investigation of BC sound, such as the complexity of experimental manipulations and individual differences between subjects resulting in difficult to interpret outcomes. One way to overcome some of those issues is the use of a simulation model for BC sound. However, until now, the published models are unable to provide a holistic response of BC sound in the human. Therefore, the primary aim of this thesis is to develop a finite element model that could simulate BC sound transmission in the human. Based on cryosectional images of a female, the LiUHead was developed as a FE model of the human head with the structure and material properties of real human. Most the structures and tissues which could contribute to the BC transmission were included in the LiUHead. The simulation results of the LiUHead agreed with experimental data obtained in both cadaver heads and live humans.

    After the development and validation of the LiUHead, the model was used to investigate BC sound.  Since BC sound is transmitted in and between the tissues, the power transmission of BC sound was investigated in the LiUHead in the frequency domain. When the stimulation was applied on the surface of the skull at the mastoid position, the results of the simulations show that, as the name suggest, the skull bone dominants the BC sound transmission. The soft tissues and cartilages are as the second most important media of the BC sound while the skull interior is the least important for the BC transmission. Moreover, according to the power flux in the skull, the BC vibrations are mainly concentrated at the skull base. Other important transmission pathways are located at the occipital bone at the posterior side of the head, but the power transmitted over the face, forehead and vertex is minor. There is power interaction between the skull bone and skull interior near the stimulation position but the transmission of sound power through the brain seem to be minimal. Since the power or energy is difficult to measure in an experimental setting, this investigation gave unique knowledge about BC sound transmission in the head and the interaction between the tissues.

    As a common application for BC sound, bone-conduction devices are used to stimulate the hearing and is a method for hearing loss rehabilitation. Nowadays many different kinds of BCDs are available. However, most studies failed to compare the different types of BCDs in the same conditions as well as between several BCDs as it is not possible to compare several BCDs within the same subject due to the implantation required for several BCDs. The model gives a unique opportunity to evaluate various BCDs in the same head. Eight different BCDs, including four kinds of skin-drive BCDs, three kinds of direct-drive BCDs, and one in-the-mouth device, were applied to the LiUHead and the simulation results were evaluated. The results proved that the direct-drive BCDs and the in-the-mouth device gave similar vibration responses at the cochlea. At low frequencies, the skin-drive BCDs had similar or even better cochlear responses than the direct-drive BCDs. However, the direct-drive BCDs gave stable responses at mid-frequencies and gave higher responses than the skin-drive BCDs at high frequencies. These results are beneficial evaluating and for designing and improving current BCDs.

    The ultimate goal of this thesis is to provide a computational model for BC sound that can be used for evaluation of BC sound transmission. This was accomplished by the LiUHead that gave results comparable to experimental data and enabled investigations that cannot easily be conducted in experiments.

    List of papers
    1. A Three-Dimensional Finite-Element Model of a Human Dry Skull for Bone-Conduction Hearing
    Open this publication in new window or tab >>A Three-Dimensional Finite-Element Model of a Human Dry Skull for Bone-Conduction Hearing
    2014 (English)In: BioMed Research International, ISSN 2314-6133, E-ISSN 2314-6141, Vol. 2014, no 519429Article in journal (Refereed) Published
    Abstract [en]

    A three-dimensional finite-element (FE) model of a human dry skull was devised for simulation of human bone-conduction (BC) hearing. Although a dry skull is a simplification of the real complex human skull, such model is valuable for understanding basic BC hearing processes. For validation of the model, the mechanical point impedance of the skull as well as the acceleration of the ipsilateral and contralateral cochlear bone was computed and compared to experimental results. Simulation results showed reasonable consistency between the mechanical point impedance and the experimental measurements when Youngs modulus for skull and polyurethane was set to be 7.3 GPa and 1 MPa with 0.01 and 0.1 loss factors at 1 kHz, respectively. Moreover, the acceleration in the medial-lateral direction showed the best correspondence with the published experimental data, whereas the acceleration in the inferior-superior direction showed the largest discrepancy. However, the results were reasonable considering that different geometries were used for the 3D FE skull and the skull used in the published experimental study. The dry skull model is a first step for understanding BC hearing mechanism in a human head and simulation results can be used to predict vibration pattern of the bone surrounding the middle and inner ear during BC stimulation.

    Place, publisher, year, edition, pages
    Hindawi Publishing Corporation, 2014
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-112658 (URN)10.1155/2014/519429 (DOI)000344143300001 ()25243148 (PubMedID)
    Note

    Funding Agencies|European Union [600933]

    Available from: 2014-12-05 Created: 2014-12-05 Last updated: 2018-04-09
    2. The development of a whole-head human finite-element model for simulation of the transmission of bone-conducted sound
    Open this publication in new window or tab >>The development of a whole-head human finite-element model for simulation of the transmission of bone-conducted sound
    2016 (English)In: Journal of the Acoustical Society of America, ISSN 0001-4966, E-ISSN 1520-8524, Vol. 140, no 3, p. 1635-1651Article in journal (Refereed) Published
    Abstract [en]

    A whole head finite element model for simulation of bone conducted (BC) sound transmission was developed. The geometry and structures were identified from cryosectional images of a female human head and eight different components were included in the model: cerebrospinal fluid, brain, three layers of bone, soft tissue, eye, and cartilage. The skull bone was modeled as a sandwich structure with an inner and outer layer of cortical bone and soft spongy bone (diploe) in between. The behavior of the finite element model was validated against experimental data of mechanical point impedance, vibration of the cochlear promontories, and transcranial BC sound transmission. The experimental data were obtained in both cadaver heads and live humans. The simulations showed multiple low-frequency resonances where the first was caused by rotation of the head and the second was close in frequency to average resonances obtained in cadaver heads. At higher frequencies, the simulation results of the impedance were within one standard deviation of the average experimental data. The acceleration response at the cochlear promontory was overall lower for the simulations compared with experiments but the overall tendencies were similar. Even if the current model cannot predict results in a specific individual, it can be used for understanding the characteristic of BC sound transmission in general. (C) 2016 Acoustical Society of America.

    Place, publisher, year, edition, pages
    ACOUSTICAL SOC AMER AMER INST PHYSICS, 2016
    National Category
    Vehicle Engineering
    Identifiers
    urn:nbn:se:liu:diva-133011 (URN)10.1121/1.4962443 (DOI)000386932500026 ()27914383 (PubMedID)
    Note

    Funding Agencies|European Union [600933]; Incheon Nation University (International Cooperative) Research Grant

    Available from: 2016-12-08 Created: 2016-12-07 Last updated: 2018-03-20
  • Public defence: 2018-04-27 13:15 Temcas, Temahuset, Linköping
    Låby, Elin
    Linköping University, Department of Thematic Studies, Department of Child Studies. Linköping University, Faculty of Arts and Sciences.
    Vinnande bilder!: Teckningstävlingar för barn 1938-20002018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    This thesis examines children’s art competitions as a changing historical phenomenon. A number of different actors have taken the initiative to involve children in competitions both at home and in school. Art competitions took place throughout the entire period from 1938 to 2000, but the format and the implications of contests became increasingly matters for debate. The analysis of the competitions problematizes the goals of the competition organizers, and the analysis of the competition pictures has examined how the children have chosen to portray various topics during different periods of time. The competitions and the pictures have thus provided the foundation for a discussion on how children and childhood were constructed during the studied time periods. The dissertation shows that during the entire period there has been an ambition from various sponsors to both use and listen to children’s voices by means of the art competitions. Continuity is seen in the sense that children’s pictures were in demand and children were regarded as competent creators of art and opinions, during the entire period studied. Changes is seen through the various discourses of childhood and children that are displayed through the competitions. For instance views concerning homeland and nation, as well as different ideals of how to depict gender and childhood relations over time. The optimistic message for the future that were depicted in the 1940’s construction of the welfare state, were during the 1970’s transformed into pictures of environmental problems and threats. But at the same time the art competitions were part of the discourse of childhood during the 1970’s where it was important to listen to the views of children. The competitions show how children were given both the possibility and the responsibility of fostering both other children and adults. Children were given a voice, but at the same time in contrast to those of the 1940’s the pictures foresaw a complex and menacing future

  • Public defence: 2018-05-03 13:00 Eken, Building 421, Floor 9, Entrance 65, Linköping
    Bustamante, Mariana
    Linköping University, Department of Medical and Health Sciences, Division of Cardiovascular Medicine. Linköping University, Faculty of Medicine and Health Sciences. Linköping University, Center for Medical Image Science and Visualization (CMIV).
    Automated Assessment of Blood Flow in the Cardiovascular System Using 4D Flow MRI2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Medical image analysis focuses on the extraction of meaningful information from medical images in order to facilitate clinical assessment, diagnostics and treatment. Image processing techniques have gradually become an essential part of the modern health care system, a consequence of the continuous technological improvements and the availability of a variety of medical imaging techniques.

    Magnetic Resonance Imaging (MRI) is an imaging technique that stands out as non-invasive, highly versatile, and capable of generating high quality images without the use of ionizing radiation. MRI is frequently performed in the clinical setting to assess the morphology and function of the heart and vessels. When focusing on the cardiovascular system, blood flow visualization and quantification is essential in order to fully understand and identify related pathologies. Among the variety of MR techniques available for cardiac imaging, 4D Flow MRI allows for full three-dimensional spatial coverage over time, also including three-directional velocity information. It is a very powerful technique that can be used for retrospective analysis of blood flow dynamics at any location in the acquired volume.

    In the clinical routine, however, flow analysis is typically done using two-dimensional imaging methods. This can be explained by their shorter acquisition times, higher in-plane spatial resolution and signal-to-noise ratio, and their relatively simpler post-processing requirements when compared to 4D Flow MRI. The extraction of useful knowledge from 4D Flow MR data is especially challenging due to the large amount of information included in these images, and typically requires substantial user interaction.

    This thesis aims to develop and evaluate techniques that facilitate the post-processing of thoracic 4D Flow MRI by automating the steps necessary to obtain hemodynamic parameters of interest from the data. The proposed methods require little to no user interaction, are fairly quick, make effective use of the information available in the four-dimensional images, and can easily be applied to sizable groups of data.The addition of the proposed techniques to the current pipeline of 4D Flow MRI analysis simplifies and expedites the assessment of these images, thus bringing them closer to the clinical routine.

    List of papers
    1. Improving left ventricular segmentation in four-dimensional flow MRI using intramodality image registration for cardiac blood flow analysis
    Open this publication in new window or tab >>Improving left ventricular segmentation in four-dimensional flow MRI using intramodality image registration for cardiac blood flow analysis
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    2018 (English)In: Magnetic Resonance in Medicine, ISSN 0740-3194, E-ISSN 1522-2594, Vol. 79, no 1, p. 554-560Article in journal (Refereed) Published
    Abstract [en]

    PurposeAssessment of blood flow in the left ventricle using four-dimensional flow MRI requires accurate left ventricle segmentation that is often hampered by the low contrast between blood and the myocardium. The purpose of this work is to improve left-ventricular segmentation in four-dimensional flow MRI for reliable blood flow analysis. MethodThe left ventricle segmentations are first obtained using morphological cine-MRI with better in-plane resolution and contrast, and then aligned to four-dimensional flow MRI data. This alignment is, however, not trivial due to inter-slice misalignment errors caused by patient motion and respiratory drift during breath-hold based cine-MRI acquisition. A robust image registration based framework is proposed to mitigate such errors automatically. Data from 20 subjects, including healthy volunteers and patients, was used to evaluate its geometric accuracy and impact on blood flow analysis. ResultsHigh spatial correspondence was observed between manually and automatically aligned segmentations, and the improvements in alignment compared to uncorrected segmentations were significant (Pamp;lt;0.01). Blood flow analysis from manual and automatically corrected segmentations did not differ significantly (Pamp;gt;0.05). ConclusionOur results demonstrate the efficacy of the proposed approach in improving left-ventricular segmentation in four-dimensional flow MRI, and its potential for reliable blood flow analysis. Magn Reson Med 79:554-560, 2018. (c) 2017 International Society for Magnetic Resonance in Medicine.

    Place, publisher, year, edition, pages
    WILEY, 2018
    Keyword
    four-dimensional flow MRI; image registration; blood flow analysis; cardiology; MRI; 4D flow MRI; image registration; blood flow analysis; cardiology; MRI
    National Category
    Medical Image Processing
    Identifiers
    urn:nbn:se:liu:diva-143887 (URN)10.1002/mrm.26674 (DOI)000417926300054 ()28303611 (PubMedID)
    Note

    Funding Agencies|ERC [310612]; 310612; Grant sponsor: Vetenskapsradet [621-2014-6191]; Hjart-Lungfonden [20140398]; Knut och Alice Wallenbergs Stiftelse [KAW 2013.0076]

    Available from: 2017-12-29 Created: 2017-12-29 Last updated: 2018-03-22
    2. Atlas-based analysis of 4D flow CMR: Automated vessel segmentation and flow quantification
    Open this publication in new window or tab >>Atlas-based analysis of 4D flow CMR: Automated vessel segmentation and flow quantification
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    2015 (English)In: Journal of Cardiovascular Magnetic Resonance, ISSN 1097-6647, E-ISSN 1532-429X, Vol. 17, no 87Article in journal (Refereed) Published
    Abstract [en]

    Background: Flow volume quantification in the great thoracic vessels is used in the assessment of several cardiovascular diseases. Clinically, it is often based on semi-automatic segmentation of a vessel throughout the cardiac cycle in 2D cine phase-contrast Cardiovascular Magnetic Resonance (CMR) images. Three-dimensional (3D), time-resolved phase-contrast CMR with three-directional velocity encoding (4D flow CMR) permits assessment of net flow volumes and flow patterns retrospectively at any location in a time-resolved 3D volume. However, analysis of these datasets can be demanding. The aim of this study is to develop and evaluate a fully automatic method for segmentation and analysis of 4D flow CMR data of the great thoracic vessels. Methods: The proposed method utilizes atlas-based segmentation to segment the great thoracic vessels in systole, and registration between different time frames of the cardiac cycle in order to segment these vessels over time. Additionally, net flow volumes are calculated automatically at locations of interest. The method was applied on 4D flow CMR datasets obtained from 11 healthy volunteers and 10 patients with heart failure. Evaluation of the method was performed visually, and by comparison of net flow volumes in the ascending aorta obtained automatically (using the proposed method), and semi-automatically. Further evaluation was done by comparison of net flow volumes obtained automatically at different locations in the aorta, pulmonary artery, and caval veins. Results: Visual evaluation of the generated segmentations resulted in good outcomes for all the major vessels in all but one dataset. The comparison between automatically and semi-automatically obtained net flow volumes in the ascending aorta resulted in very high correlation (r(2) = 0.926). Moreover, comparison of the net flow volumes obtained automatically in other vessel locations also produced high correlations where expected: pulmonary trunk vs. proximal ascending aorta (r(2) = 0.955), pulmonary trunk vs. pulmonary branches (r(2) = 0.808), and pulmonary trunk vs. caval veins (r(2) = 0.906). Conclusions: The proposed method allows for automatic analysis of 4D flow CMR data, including vessel segmentation, assessment of flow volumes at locations of interest, and 4D flow visualization. This constitutes an important step towards facilitating the clinical utility of 4D flow CMR.

    Place, publisher, year, edition, pages
    BIOMED CENTRAL LTD, 2015
    Keyword
    4D flow cardiovascular magnetic resonance (4D flow CMR); Flow volume; Image segmentation; Image registration; Phase contrast
    National Category
    Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-122197 (URN)10.1186/s12968-015-0190-5 (DOI)000362164100002 ()26438074 (PubMedID)
    Note

    Funding Agencies|Swedish Heart and Lung foundation; Swedish Research Council; European Research Council (HEART4FLOW) [310612]

    Available from: 2015-10-26 Created: 2015-10-23 Last updated: 2018-03-22
    3. Improving visualization of 4D flow cardiovascular magnetic resonance with four-dimensional angiographic data: generation of a 4D phase-contrast magnetic resonance CardioAngiography (4D PC-MRCA)
    Open this publication in new window or tab >>Improving visualization of 4D flow cardiovascular magnetic resonance with four-dimensional angiographic data: generation of a 4D phase-contrast magnetic resonance CardioAngiography (4D PC-MRCA)
    2017 (English)In: Journal of Cardiovascular Magnetic Resonance, ISSN 1097-6647, E-ISSN 1532-429X, Vol. 19, article id 47Article in journal (Refereed) Published
    Abstract [en]

    Magnetic Resonance Angiography (MRA) and Phase-Contrast MRA (PC-MRA) approaches used for assessment of cardiovascular morphology typically result in data containing information from the entire cardiac cycle combined into one 2D or 3D image. Information specific to each timeframe of the cardiac cycle is, however, lost in this process. This study proposes a novel technique, called Phase-Contrast Magnetic Resonance CardioAngiography (4D PC-MRCA), that utilizes the full potential of 4D Flow CMR when generating temporally resolved PC-MRA data to improve visualization of the heart and major vessels throughout the cardiac cycle. Using non-rigid registration between the timeframes of the 4D Flow CMR acquisition, the technique concentrates information from the entire cardiac cycle into an angiographic dataset at one specific timeframe, taking movement over the cardiac cycle into account. Registration between the timeframes is used once more to generate a time-resolved angiography. The method was evaluated in ten healthy volunteers. Visual comparison of the 4D PC-MRCAs versus PC-MRAs generated from 4D Flow CMR using the traditional approach was performed by two observers using Maximum Intensity Projections (MIPs). The 4D PC-MRCAs resulted in better visibility of the main anatomical regions of the cardiovascular system, especially where cardiac or vessel motion was present. The proposed method represents an improvement over previous PC-MRA generation techniques that rely on 4D Flow CMR, as it effectively utilizes all the information available in the acquisition. The 4D PC-MRCA can be used to visualize the motion of the heart and major vessels throughout the entire cardiac cycle.

    Place, publisher, year, edition, pages
    BIOMED CENTRAL LTD, 2017
    Keyword
    Computer-Assisted Image Analysis; 4D flow cardiovascular magnetic resonance (4D flow CMR); Phase-Contrast Magnetic Resonance Angiography (PC-MRA)
    National Category
    Radiology, Nuclear Medicine and Medical Imaging
    Identifiers
    urn:nbn:se:liu:diva-139277 (URN)10.1186/s12968-017-0360-8 (DOI)000404063800001 ()28645326 (PubMedID)
    Note

    Funding Agencies|European Research Council [310612]; Swedish Heart and Lung foundation [20140398]; Swedish Research Council [621-2014-6191]

    Available from: 2017-07-07 Created: 2017-07-07 Last updated: 2018-03-22
    4. Creating Hemodynamic Atlases of Cardiac 4D Flow MRI
    Open this publication in new window or tab >>Creating Hemodynamic Atlases of Cardiac 4D Flow MRI
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    2017 (English)In: Journal of Magnetic Resonance Imaging, ISSN 1053-1807, E-ISSN 1522-2586, Vol. 46, no 5, p. 1389-1399Article in journal (Refereed) Published
    Abstract [en]

    Purpose: Hemodynamic atlases can add to the pathophysiological understanding of cardiac diseases. This study proposes a method to create hemodynamic atlases using 4D Flow magnetic resonance imaging (MRI). The method is demonstrated for kinetic energy (KE) and helicity density (Hd). Materials and Methods: Thirteen healthy subjects underwent 4D Flow MRI at 3T. Phase-contrast magnetic resonance cardioangiographies (PC-MRCAs) and an average heart were created and segmented. The PC-MRCAs, KE, and Hd were nonrigidly registered to the average heart to create atlases. The method was compared with 1) rigid, 2) affine registration of the PC-MRCAs, and 3) affine registration of segmentations. The peak and mean KE and Hd before and after registration were calculated to evaluate interpolation error due to nonrigid registration. Results: The segmentations deformed using nonrigid registration overlapped (median: 92.3%) more than rigid (23.1%, P amp;lt; 0.001), and affine registration of PC-MRCAs (38.5%, P amp;lt; 0.001) and affine registration of segmentations (61.5%, P amp;lt; 0.001). The peak KE was 4.9 mJ using the proposed method and affine registration of segmentations (P50.91), 3.5 mJ using rigid registration (P amp;lt; 0.001), and 4.2 mJ using affine registration of the PC-MRCAs (P amp;lt; 0.001). The mean KE was 1.1 mJ using the proposed method, 0.8 mJ using rigid registration (P amp;lt; 0.001), 0.9 mJ using affine registration of the PC-MRCAs (P amp;lt; 0.001), and 1.0 mJ using affine registration of segmentations (P50.028). The interpolation error was 5.262.6% at mid-systole, 2.863.8% at early diastole for peak KE; 9.669.3% at mid-systole, 4.064.6% at early diastole, and 4.964.6% at late diastole for peak Hd. The mean KE and Hd were not affected by interpolation. Conclusion: Hemodynamic atlases can be obtained with minimal user interaction using nonrigid registration of 4D Flow MRI. Level of Evidence: 2 Technical Efficacy: Stage 1

    Place, publisher, year, edition, pages
    WILEY, 2017
    National Category
    Medical Image Processing
    Identifiers
    urn:nbn:se:liu:diva-142968 (URN)10.1002/jmri.25691 (DOI)000412894800015 ()28295788 (PubMedID)
    Note

    Funding Agencies|ERC [Heart4flow, 310612]; Swedish Research Council [621-2014-6191]; Swedish Heart and Lung Foundation [20140398]

    Available from: 2017-11-13 Created: 2017-11-13 Last updated: 2018-03-22
  • Public defence: 2018-05-04 13:00 K1, Kåkenhus, Norrköping
    Hjelmfors, Lisa
    Linköping University, Department of Social and Welfare Studies, Division of Nursing Science. Linköping University, Faculty of Medicine and Health Sciences.
    Communication about the Heart Failure Trajectory in Patients, their Families and Health Care Professionals2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Introduction: There is an increasing awareness in the field of cardiology regarding the need for improved delivery of palliative care in patients with heart failure (HF). Professional guidelines have drawn attention to the importance of discussing the heart failure trajectory with patients and their families. These discussions can include, for example, talking about the prognosis, expectations for the future, and care at the end-of-life. It seems difficult for health care professionals to choose the right time for initiating these discussions. They often avoid these conversations because they are afraid of taking away hope and make the patients and their families anxious.

    Aim: The overall aim of this thesis was to improve communication about the heart failure trajectory in patients, their families, and health care professionals.

    Design and methods: This thesis includes five studies using different designs and data collection methods. Study I has a cross-sectional design using a questionnaire to collect data to describe heart failure nurses’ perceptions of and practice in discussing prognosis and end-of-life care with heart failure patients. Study II has a descriptive and comparative design, where a survey was performed to describe Swedish and Dutch heart failure nurses’ reasons for discussing or not discussing prognosis and end-of-life care with patients. Study III has an inductive and exploratory design, where HF patients participated in focus groups or individual interviews. Data was collected based on their perceptions of communication about the heart failure prognosis. Study IV was a small-scale ethnographic study describing and evaluating the delivery of a simulation when teaching third-year nursing students about end-of-life care at a Swedish university. Study V used co-design in which patients with HF from primary care, their family members and health care professionals (physicians and nurses) from palliative and HF care were invited to be constructive participants in the design process of a communication intervention. Health care professionals participated in a first feasibility testing of the intervention.

    Results: Most Swedish HF nurses had discussed prognosis (96%) and end-of-life care (84%) with a HF patient at some point in clinical practice. The nurses often reported that a physician was to have the main responsibility for such discussions (69%), but that the nurse was also believed to have a role to play (I). Prognosis and end-of-life care were, together with sexual activity, () the three least frequently discussed topics in HF clinics in both Sweden and the Netherlands (II). In conversations with 1,809 Swedish and Dutch HF patients, prognosis was discussed with 38% of the patients and end-of-life care was discussed with 10%. In study III, patients expressed different experiences of and preferences for communication about their HF prognosis. Many patients described that the health care professionals had not provided them with any prognosis information at all. The patients had different understandings of HF as a chronic illness, which had an impact on their preferences for communication about their prognosis (III). The simulation training described in the ethnographic study (IV) was part of an end-of-life care simulation during the last term of the 3- year bachelor degree level nursing education program, where students learn and practice basic palliative care. The students felt that the simulation training was a good opportunity to practice handling end-of- life situations as it gave them a chance to experience this situation and their own feelings and thoughts on death and dying. In study V, an intervention to improve communication about prognosis and end-of-life care in HF care was developed and some areas were feasibility tested. Heart failure patients, their families and health care professionals working in HF care or palliative care participated in the development process. Health care professionals (nurses and physicians) participated in the following feasibility testing of the intervention.

    Conclusions: This thesis shows that prognosis and end-of-life care are seldom discussed with HF patients in Swedish and Dutch heart failure care. and that many heart failure nurses have ambiguous attitudes towards discussing these topics with patients and their families (I+II). The patients described that they receive different messages concerning their heart failure, and that they also have different preferences for discussing the heart failure trajectory with health care professionals. The professionals need to understand the impact of heart failure on each patient and adapt the communication to each individual (III). End-of-life care simulation with skilled supervisors shows great promise for health care professionals to learn good communication skills in end-of-life care conversations (IV). A Question Prompt List and a communication course might be useful for improving communication about the heart failure trajectory in patients, their families, and health care professionals

    List of papers
    1. Communicating prognosis and end-of-life care to heart failure patients: a survey of heart failure nurses' perspectives
    Open this publication in new window or tab >>Communicating prognosis and end-of-life care to heart failure patients: a survey of heart failure nurses' perspectives
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    2014 (English)In: European Journal of Cardiovascular Nursing, ISSN 1474-5151, E-ISSN 1873-1953, Vol. 13, no 2, p. 152-161Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND:

    Many heart failure (HF) patients have palliative care needs, but communication about prognosis and end-of-life care is lacking. HF nurses can play an important role in such communication, but their views on this have rarely been sought.

    AIMS:

    This study aims to describe HF nurses' perspectives on, and daily practice regarding, discussing prognosis and end-of-life care with HF patients in outpatient care. It further aims to explore barriers, facilitators and related factors for discussing these issues.

    METHODS:

    A national survey including nurses from outpatient clinics and primary health care centres was performed. Data was collected using a questionnaire on communication with HF patients about prognosis and end-of-life care.

    RESULTS:

    In total, 111 (82%) of the HF nurses completed the questionnaire. Most of them reported that physicians should have the main responsibility for discussing prognosis (69%) and end-of-life care (67%). Most nurses felt knowledgeable to have these discussions, but 91% reported a need for further training in at least one of the areas. Barriers for communication about prognosis and end-of-life care included the unpredictable trajectory of HF, patients' comorbidities and the opinion that patients in NYHA class II-III are not in the end-of-life.

    CONCLUSION:

    Although HF nurses feel competent discussing prognosis and end-of-life care with the HF patient, they are hesitant to have these conversations. This might be partly explained by the fact that they consider the physician to be responsible for such conversations, and by perceived barriers to communication. This implies a need for clinical policy and education for HF nurses to expand their knowledge and awareness of the patients' possible needs for palliative care.

    Place, publisher, year, edition, pages
    Sage Publications, 2014
    Keyword
    Heart failure, communication, end-of-life care, nurse attitudes, palliative care, prognosis
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-106263 (URN)10.1177/1474515114521746 (DOI)24480779 (PubMedID)2-s2.0-84896797220 (Scopus ID)
    Available from: 2014-05-02 Created: 2014-05-02 Last updated: 2018-03-14Bibliographically approved
    2. Patient-Nurse Communication about Prognosis and End-of-Life Care
    Open this publication in new window or tab >>Patient-Nurse Communication about Prognosis and End-of-Life Care
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    2015 (English)In: Journal of Palliative Medicine, ISSN 1096-6218, E-ISSN 1557-7740, Vol. 18, no 10, p. 865-871Article in journal (Refereed) Published
    Abstract [en]

    Background: Although several studies advise that discussions about prognosis and end-of-life care should be held throughout the whole heart failure (HF) trajectory, data is lacking on the prevalence and practice of such discussions in HF care. Objective: The study objective was to explore how often and why HF nurses in outpatient clinics discuss prognosis and end-of-life care in the context of patient education. Methods: This was a descriptive and comparative study. Participants were HF nurses from Swedish and Dutch HF outpatient clinics. Measurements were taken via a survey for both quantitative and qualitative data. Additional data was collected via open-ended questions and analyzed with content analysis. Results: Two hundred seventy-nine nurses registered 1809 patient conversations using a checklist. Prognosis and end-of-life care were among the least frequently discussed topics, whereas symptoms of HF was discussed most often. Prognosis was discussed with 687 patients (38%), and end-of-life care was discussed with 179 patients (10%). Prognosis and end-of-life care were discussed more frequently in The Netherlands than in Sweden (41% versus 34%, pless than0.001, 13% versus 4%, pless than0.001). The nurses did not always recognize prognosis and end-of-life care discussions as a part of their professional role. Conclusions: Currently, patient-nurse communication about prognosis and end-of-life care does not seem to be routine in patient education in HF clinics, and these discussions could be included more often. The reasons for nurses to discuss these topics were related to clinical routines, the patients situation, and professional responsibilities. To improve future care, communication with patients needs to be further developed.

    Place, publisher, year, edition, pages
    MARY ANN LIEBERT, INC, 2015
    National Category
    Sociology Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-122208 (URN)10.1089/jpm.2015.0037 (DOI)000362268900013 ()26068058 (PubMedID)
    Note

    Funding Agencies|Heart and Lung Foundation; King Gustaf V and Queen Victorias Foundation of the Freemasons

    Available from: 2015-10-26 Created: 2015-10-23 Last updated: 2018-03-14
    3. Simulation to Teach Nursing Students About End-of-Life Care
    Open this publication in new window or tab >>Simulation to Teach Nursing Students About End-of-Life Care
    Show others...
    2016 (English)In: Journal of Hospice and Palliative Nursing, ISSN 1522-2179, E-ISSN 1539-0705, Vol. 18, no 6, p. 512-518Article in journal (Refereed) Published
    Abstract [en]

    There is minimal education on death and dying in undergraduate nursing programs, leaving the students unprepared to provide sufficient care to dying patients and their families. This article describes a teaching innovation on how end-of-life care simulation can provide a successful and appreciated learning situation for nursing students, teaching them communication skills in challenging situations. Modifications in the setup of the simulation might help the students to focus more on communication and existential issues instead of mostly practical ones.

    Place, publisher, year, edition, pages
    Lippincott Williams & Wilkins, 2016
    Keyword
    end of life care education, simulation, undergraduate nursing students
    National Category
    Nursing
    Identifiers
    urn:nbn:se:liu:diva-133105 (URN)10.1097/NJH.0000000000000279 (DOI)000387682700005 ()
    Available from: 2016-12-12 Created: 2016-12-09 Last updated: 2018-03-14Bibliographically approved
  • Public defence: 2018-05-04 13:15 Ada Lovelace, B-huset, Linköping
    Wahlsten, Markus
    Linköping University, Department of Mathematics, Computational Mathematics. Linköping University, Faculty of Science & Engineering.
    Uncertainty quantification for wave propagation and flow problems with random data2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    In this thesis we study partial differential equations with random inputs. The effects that different boundary conditions with random data and uncertain geometries have on the solution are analyzed. Further, comparisons and couplings between different uncertainty quantification methods are performed. The numerical simulations are based on provably strongly stable finite difference formulations based on summation-by-parts operators and a weak implementation of boundary and interface conditions.

    The first part of this thesis treats the construction of variance reducing boundary conditions. It is shown how the variance of the solution can be manipulated by the choice of boundary conditions, and a close relation between the variance of the solution and the energy estimate is established. The technique is studied on both a purely hyperbolic system as well as an incompletely parabolic system of equations. The applications considered are the Euler, Maxwell's, and Navier--Stokes equations.

    The second part focuses on the effect of uncertain geometry on the solution. We consider a two-dimensional advection-diffusion equation with a stochastically varying boundary. We transform the problem to a fixed domain where comparisons can be made. Numerical results are performed on a problem in heat transfer, where the frequency and amplitude of the prescribed uncertainty are varied.

    The final part of the thesis is devoted to the comparison and coupling of different uncertainty quantification methods. An efficiency analysis is performed using the intrusive polynomial chaos expansion with stochastic Galerkin projection, and nonintrusive numerical integration. The techniques are compared using the non-linear viscous Burgers' equation. A provably stable coupling procedure for the two methods is also constructed. The general coupling procedure is exemplified using a hyperbolic system of equations.

    List of papers
    1. Variance reduction through robust design of boundary conditions for stochastic hyperbolic systems of equations
    Open this publication in new window or tab >>Variance reduction through robust design of boundary conditions for stochastic hyperbolic systems of equations
    2015 (English)In: Journal of Computational Physics, ISSN 0021-9991, E-ISSN 1090-2716, Vol. 282, p. 1-22Article in journal (Refereed) Published
    Abstract [en]

    We consider a hyperbolic system with uncertainty in the boundary and initial data. Our aim is to show that different boundary conditions gives different convergence rates of the variance of the solution. This means that we can with the same knowledge of data get a more or less accurate description of the uncertainty in the solution. A variety of boundary conditions are compared and both analytical and numerical estimates of the variance of the solution is presented. As applications, we study the effect of this technique on Maxwell's equations as well as on a subsonic outflow boundary for the Euler equations.

    Place, publisher, year, edition, pages
    Elsevier, 2015
    Keyword
    Uncertainty quantification, hyperbolic system, initial boundary value problems, well posed, stability, boundary conditions, stochastic data, variance reduction, robust design, summation-by parts
    National Category
    Computational Mathematics
    Identifiers
    urn:nbn:se:liu:diva-111893 (URN)10.1016/j.jcp.2014.10.061 (DOI)000346430700001 ()
    Available from: 2014-11-07 Created: 2014-11-07 Last updated: 2018-04-09
    2. Robust Boundary Conditions for Stochastic Incompletely Parabolic Systems of Equations
    Open this publication in new window or tab >>Robust Boundary Conditions for Stochastic Incompletely Parabolic Systems of Equations
    2016 (English)Report (Other academic)
    Abstract [en]

    We study an incompletely parabolic system in three space dimensions with stochastic boundary and initial data. We show how the variance of the solution can be manipulated by the boundary conditions, while keeping the mean value of the solution unaffected. Estimates of the variance of the solution is presented both analytically and numerically. We exemplify the technique by applying it to an incompletely parabolic model problem, as well as the one-dimensional compressible Navier-Stokes equations.

    Place, publisher, year, edition, pages
    Linköping: Linköping University Electronic Press, 2016. p. 39
    Series
    LiTH-MAT-R, ISSN 0348-2960 ; 19
    Keyword
    uncertainty quantifcation, incompletely parabolic system, initial boundary value problems, stochastic data, variance reduction, robust design
    National Category
    Computational Mathematics
    Identifiers
    urn:nbn:se:liu:diva-133365 (URN)LiTH-MAT-R--2016/19--SE (ISRN)
    Available from: 2016-12-22 Created: 2016-12-22 Last updated: 2018-04-09Bibliographically approved
    3. The effect of uncertain geometries on advection–diffusion of scalar quantities
    Open this publication in new window or tab >>The effect of uncertain geometries on advection–diffusion of scalar quantities
    2017 (English)In: BIT Numerical Mathematics, ISSN 0006-3835, E-ISSN 1572-9125, Vol. 226, no 1Article in journal (Refereed) Published
    Abstract [en]

    The two dimensional advection–diffusion equation in a stochastically varyinggeometry is considered. The varying domain is transformed into a fixed one andthe numerical solution is computed using a high-order finite difference formulationon summation-by-parts form with weakly imposed boundary conditions. Statistics ofthe solution are computed non-intrusively using quadrature rules given by the probabilitydensity function of the random variable. As a quality control, we prove that thecontinuous problem is strongly well-posed, that the semi-discrete problem is stronglystable and verify the accuracy of the scheme. The technique is applied to a heat transferproblem in incompressible flow. Statistical properties such as confidence intervals andvariance of the solution in terms of two functionals are computed and discussed. Weshow that there is a decreasing sensitivity to geometric uncertainty as we graduallylower the frequency and amplitude of the randomness. The results are less sensitiveto variations in the correlation length of the geometry.

    Keyword
    Incompressible flow, Advection–diffusion, Uncertainty quantification, Uncertain geometry, Boundary conditions, Parabolic problems, Variable coefficient, Temperature field, Heat transfer
    National Category
    Mathematics
    Identifiers
    urn:nbn:se:liu:diva-140135 (URN)10.1007/s10543-017-0676-7 (DOI)
    Available from: 2017-08-31 Created: 2017-08-31 Last updated: 2018-04-09
    4. Stochastic Galerkin Projection and Numerical Integration for Stochastic Investigations of the Viscous Burgers’ Equation
    Open this publication in new window or tab >>Stochastic Galerkin Projection and Numerical Integration for Stochastic Investigations of the Viscous Burgers’ Equation
    2018 (English)Report (Other academic)
    Abstract [en]

    We consider a stochastic analysis of the non-linear viscous Burgers’ equation and focus on the comparison between intrusive and non-intrusive uncer- tainty quantification methods. The intrusive approach uses a combination of polynomial chaos and stochastic Galerkin projection. The non-intrusive method uses numerical integration by combining quadrature rules and the probability density functions of the prescribed uncertainties. The two methods are applied to a provably stable formulation of the viscous Burgers’ equation, and compared. As measures of comparison: variance size, computational efficiency and accuracy are used.

    Place, publisher, year, edition, pages
    Linköping: Linköping University Electronic Press, 2018. p. 14
    Series
    LiTH-MAT-R, ISSN 0348-2960 ; 2018:2
    Keyword
    Uncertainty quantification, stochastic data, polynomial chaos, stochastic Galerkin, intrusive methods, non-intrusive methods, Burgers’ equation
    National Category
    Mathematics
    Identifiers
    urn:nbn:se:liu:diva-146038 (URN)LiTH-MAT-R--2018/02--SE (ISRN)
    Available from: 2018-03-22 Created: 2018-03-22 Last updated: 2018-04-09Bibliographically approved
    5. An efficient hybrid method for uncertainty quantification
    Open this publication in new window or tab >>An efficient hybrid method for uncertainty quantification
    2018 (English)Report (Other academic)
    Abstract [en]

    A technique for coupling an intrusive and non-intrusive uncertainty quantification method is proposed. The intrusive approach uses a combination of polynomial chaos and stochastic Galerkin projection. The non-intrusive method uses numerical integration by combining quadrature rules and the probability density functions of the prescribed uncertainties. A strongly stable coupling procedure between the two methods at an interface is constructed. The efficiency of the hybrid method is exemplified using a hyperbolic system of equations, and verified by numerical experiments.

    Place, publisher, year, edition, pages
    Linköping: Linköping University Electronic Press, 2018. p. 20
    Series
    LiTH-MAT-R, ISSN 0348-2960 ; 2018:3
    Keyword
    Uncertainty quantification, numerical integration, stochastic Galerkin, polynomial chaos, coupling, projection operator
    National Category
    Mathematics
    Identifiers
    urn:nbn:se:liu:diva-146036 (URN)LiTH-MAT-R--2018/03--SE (ISRN)
    Available from: 2018-03-22 Created: 2018-03-22 Last updated: 2018-04-09Bibliographically approved
  • Public defence: 2018-05-09 09:00 Eken, Linköping
    Gawel, Danuta R.
    Linköping University, Department of Clinical and Experimental Medicine, Division of Children's and Women's health. Linköping University, Faculty of Medicine and Health Sciences.
    Identification of genes and regulators that are shared across T cell associated diseases2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Genome-wide association studies (GWASs) of hundreds of diseases and millions of patients have led to the identification of genes that are associated with more than one disease. The aims of this PhD thesis were to a) identify a group of genes important in multiple diseases (shared disease genes), b) identify shared up-stream disease regulators, and c) determine how the same genes can be involved in the pathogenesis of different diseases. These aims have been tested on CD4+ T cells because they express the T helper cell differentiation pathway, which was the most enriched pathway in analyses of all disease associated genes identified with GWASs.

    Combining information about known gene-gene interactions from the protein-protein interaction (PPI) network with gene expression changes in multiple T cell associated diseases led to the identification of a group of highly interconnected genes that were miss-expressed in many of those diseases – hereafter called ‘shared disease genes’. Those genes were further enriched for inflammatory, metabolic and proliferative pathways, genetic variants identified by all GWASs, as well as mutations in cancer studies and known diagnostic and therapeutic targets. Taken together, these findings supported the relevance of the shared disease genes.

    Identification of the shared upstream disease regulators was addressed in the second project of this PhD thesis. The underlying hypothesis assumed that the determination of the shared upstream disease regulators is possible through a network model showing in which order genes activate each other. For that reason a transcription factor–gene regulatory network (TF-GRN) was created. The TF-GRN was based on the time-series gene expression profiling of the T helper cell type 1 (Th1), and T helper cell type 2 (Th2) differentiation from Native T-cells. Transcription factors (TFs) whose expression changed early during polarization and had many downstream predicted targets (hubs) that were enriched for disease associated single nucleotide polymorphisms (SNPs) were prioritised as the putative early disease regulators. These analyses identified three transcription factors: GATA3, MAF and MYB. Their predicted targets were validated by ChIP-Seq and siRNA mediated knockdown in primary human T-cells. CD4+ T cells isolated from seasonal allergic rhinitis (SAR) and multiple sclerosis (MS) patients in their non-symptomatic stages were analysed in order to demonstrate predictive potential of those three TFs. We found that those three TFs were differentially expressed in symptom-free stages of the two diseases, while their TF-GRN{predicted targets were differentially expressed during symptomatic disease stages. Moreover, using RNA-Seq data we identified a disease associated SNP that correlated with differential splicing of GATA3.

    A limitation of the above study is that it concentrated on TFs as main regulators in cells, excluding other potential regulators such as microRNAs. To this end, a microRNA{gene regulatory network (mGRN) of human CD4+ T cell differentiation was constructed. Within this network, we defined regulatory clusters (groups of microRNAs that are regulating groups of mRNAs). One regulatory cluster was differentially expressed in all of the tested diseases, and was highly enriched for GWAS SNPs. Although the microRNA processing machinery was dynamically upregulated during early T-cell activation, the majority of microRNA modules showed specialisation in later time-points.

    In summary this PhD thesis shows the relevance of shared genes and up-stream disease regulators. Putative mechanisms of why shared genes can be involved in pathogenesis of different diseases have also been demonstrated: a) differential gene expression in different diseases; b) alternative transcription factor splicing variants may affect different downstream gene target group; and c) SNPs might cause alternative splicing.

    List of papers
    1. Integrated genomic and prospective clinical studies show the importance of modular pleiotropy for disease susceptibility, diagnosis and treatment
    Open this publication in new window or tab >>Integrated genomic and prospective clinical studies show the importance of modular pleiotropy for disease susceptibility, diagnosis and treatment
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    2014 (English)In: Genome Medicine, ISSN 1756-994X, E-ISSN 1756-994X, Vol. 6, no 17Article in journal (Refereed) Published
    Abstract [en]

    Background: Translational research typically aims to identify and functionally validate individual, disease-specific genes. However, reaching this aim is complicated by the involvement of thousands of genes in common diseases, and that many of those genes are pleiotropic, that is, shared by several diseases. Methods: We integrated genomic meta-analyses with prospective clinical studies to systematically investigate the pathogenic, diagnostic and therapeutic roles of pleiotropic genes. In a novel approach, we first used pathway analysis of all published genome-wide association studies (GWAS) to find a cell type common to many diseases. Results: The analysis showed over-representation of the T helper cell differentiation pathway, which is expressed in T cells. This led us to focus on expression profiling of CD4(+) T cells from highly diverse inflammatory and malignant diseases. We found that pleiotropic genes were highly interconnected and formed a pleiotropic module, which was enriched for inflammatory, metabolic and proliferative pathways. The general relevance of this module was supported by highly significant enrichment of genetic variants identified by all GWAS and cancer studies, as well as known diagnostic and therapeutic targets. Prospective clinical studies of multiple sclerosis and allergy showed the importance of both pleiotropic and disease specific modules for clinical stratification. Conclusions: In summary, this translational genomics study identified a pleiotropic module, which has key pathogenic, diagnostic and therapeutic roles.

    Place, publisher, year, edition, pages
    BioMed Central, 2014
    National Category
    Clinical Medicine Basic Medicine
    Identifiers
    urn:nbn:se:liu:diva-106873 (URN)10.1186/gm534 (DOI)000334631300002 ()
    Available from: 2014-05-28 Created: 2014-05-23 Last updated: 2018-04-10
    2. A validated gene regulatory network and GWAS identifies early regulators of T cell-associated diseases
    Open this publication in new window or tab >>A validated gene regulatory network and GWAS identifies early regulators of T cell-associated diseases
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    2015 (English)In: Science Translational Medicine, ISSN 1946-6234, E-ISSN 1946-6242, Vol. 7, no 313, article id 313ra178Article in journal (Refereed) Published
    Abstract [en]

    Early regulators of disease may increase understanding of disease mechanisms and serve as markers for presymptomatic diagnosis and treatment. However, early regulators are difficult to identify because patients generally present after they are symptomatic. We hypothesized that early regulators of T cell-associated diseases could be found by identifying upstream transcription factors (TFs) in T cell differentiation and by prioritizing hub TFs that were enriched for disease-associated polymorphisms. A gene regulatory network (GRN) was constructed by time series profiling of the transcriptomes and methylomes of human CD4(+) T cells during in vitro differentiation into four helper T cell lineages, in combination with sequence-based TF binding predictions. The TFs GATA3, MAF, and MYB were identified as early regulators and validated by ChIP-seq (chromatin immunoprecipitation sequencing) and small interfering RNA knockdowns. Differential mRNA expression of the TFs and their targets in T cell-associated diseases supports their clinical relevance. To directly test if the TFs were altered early in disease, T cells from patients with two T cell-mediated diseases, multiple sclerosis and seasonal allergic rhinitis, were analyzed. Strikingly, the TFs were differentially expressed during asymptomatic stages of both diseases, whereas their targets showed altered expression during symptomatic stages. This analytical strategy to identify early regulators of disease by combining GRNs with genome-wide association studies may be generally applicable for functional and clinical studies of early disease development.

    Place, publisher, year, edition, pages
    AMER ASSOC ADVANCEMENT SCIENCE, 2015
    National Category
    Biological Sciences Clinical Medicine
    Identifiers
    urn:nbn:se:liu:diva-123522 (URN)10.1126/scitranslmed.aad2722 (DOI)000365237400003 ()26560356 (PubMedID)
    Note

    Funding Agencies|Cancer fund, Swedish Medical Research Council [K2013-61X-22310-01-04, 2012-3168]; Academy of Finland Centre of Excellence in Molecular Systems Immunology and Physiology Research [250114]; Sigrid Juselius Foundation; Generalitat de Catalunya AGAUR [2014-SGR364]; Spanish Association Against Cancer; Spanish Ministry of Health ISCIII FIS [PI12/01528]; RTICC [RD12/0036/0008]

    Available from: 2015-12-22 Created: 2015-12-21 Last updated: 2018-04-10Bibliographically approved
  • Public defence: 2018-05-09 13:00 Berzeliussalen, Linköping
    Renhorn, Jakob
    Linköping University, Department of Clinical and Experimental Medicine, Divison of Neurobiology. Linköping University, Faculty of Medicine and Health Sciences.
    Conformational Changes during Potassium-Channel Gating2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Voltage-gated ion channels have a paramount importance in many physiological processes such as cell-to-cell communication, action potential-propagation, and cell motility. Voltage-gated ion channels are characterized by their ability to sense membrane voltage and to greatly change channel activity in response to small changes in the voltage. The ability to sense voltage resides in the four voltage-sensor domains (VSDs) surrounding the central ion-conducting pore. Membrane depolarization causes the inside of the membrane to become positively charged, electrostatically repelling the positively charged fourth transmembrane segment (S4), or voltage sensor, in the VSD, causing the voltage sensor to move outwards. This motion provides necessary energy to open the pore and allow ion conductivity. Prolonged channel activation leads to alterations in the selectivity filter which cease ion conductivity, in a process called slow inactivation. In this thesis, we investigated the movement of S4 during activation of the channel. We also studied the communication between the four subunits during activation as well as the communication between the pore domain and VSD during slow inactivation.

    We have shown that voltage sensors move approximately 12 Å outwards during activation. The positively charged amino acid residues in S4 create temporary salt bridges with negative counter-charges in the other segments of the VSD as it moves through a membrane. We have also shown that the movement of one of the four voltage sensors can affect the movement of the neighboring voltage sensors. When at least one voltage sensor has moved to an up-position, it stabilizes other voltage sensors in the up-position, increasing the energy required for the voltage sensor to return to the down position.

    We have also shown reciprocal communication between the pore domain and the VSDs. Alterations in the VSD or the interface between the pore and the VSD cause changes in the rate of slow inactivation. Likewise, modifications in the pore domain cause changes to the voltage-sensor movement. This indicates communication between the pore and the VSD during slow inactivation.

    The information from our work could be used to find new approaches when designing channel-modifying drugs for the treatment of diseases caused by increased neuronal excitability, such as chronic pain and epilepsy.

    List of papers
    1. Tracking a complete voltage-sensor cycle with metal-ion bridges
    Open this publication in new window or tab >>Tracking a complete voltage-sensor cycle with metal-ion bridges
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    2012 (English)In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 109, no 22, p. 8552-8557Article in journal (Refereed) Published
    Abstract [en]

    Voltage-gated ion channels open and close in response to changes in membrane potential, thereby enabling electrical signaling in excitable cells. The voltage sensitivity is conferred through four voltage-sensor domains (VSDs) where positively charged residues in the fourth transmembrane segment (S4) sense the potential. While an open state is known from the Kv1.2/2.1 X-ray structure, the conformational changes underlying voltage sensing have not been resolved. We present 20 additional interactions in one open and four different closed conformations based on metal-ion bridges between all four segments of the VSD in the voltage-gated Shaker K channel. A subset of the experimental constraints was used to generate Rosetta models of the conformations that were subjected to molecular simulation and tested against the remaining constraints. This achieves a detailed model of intermediate conformations during VSD gating. The results provide molecular insight into the transition, suggesting that S4 slides at least 12 angstrom along its axis to open the channel with a 3(10) helix region present that moves in sequence in S4 in order to occupy the same position in space opposite F290 from open through the three first closed states.

    Place, publisher, year, edition, pages
    National Academy of Sciences, 2012
    Keyword
    electrophysiology, inactivation, Xenopus oocytes, voltage clamp, conformational transition
    National Category
    Medical and Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-78812 (URN)10.1073/pnas.1116938109 (DOI)000304881700044 ()
    Note

    Funding Agencies|Swedish Research Council||Swedish Heart-Lung Foundation||Swedish Brain Foundation||County Council of Ostergotland||Queen Silvias Anniversary Foundation||King Gustaf V and Queen Victorias Freemasons Foundation||Stina and Birger Johanssons Foundation||Swedish Society for Medical Research||Swedish Foundation for Strategic Research||European Research Council||

    Available from: 2012-06-21 Created: 2012-06-21 Last updated: 2018-04-09
    2. Reciprocal voltage sensor-to-pore coupling leads to potassium channel C-type inactivation
    Open this publication in new window or tab >>Reciprocal voltage sensor-to-pore coupling leads to potassium channel C-type inactivation
    Show others...
    2016 (English)In: Scientific Reports, ISSN 2045-2322, E-ISSN 2045-2322, Vol. 6, article id 27562Article in journal (Refereed) Published
    Abstract [en]

    Voltage-gated potassium channels open at depolarized membrane voltages. A prolonged depolarization causes a rearrangement of the selectivity filter which terminates the conduction of ions - a process called slow or C-type inactivation. How structural rearrangements in the voltage-sensor domain (VSD) cause alteration in the selectivity filter, and vice versa, are not fully understood. We show that pulling the pore domain of the Shaker potassium channel towards the VSD by a Cd2+ bridge accelerates C-type inactivation. Molecular dynamics simulations show that such pulling widens the selectivity filter and disrupts the K+ coordination, a hallmark for C-type inactivation. An engineered Cd2+ bridge within the VSD also affect C-type inactivation. Conversely, a pore domain mutation affects VSD gating-charge movement. Finally, C-type inactivation is caused by the concerted action of distant amino acid residues in the pore domain. All together, these data suggest a reciprocal communication between the pore domain and the VSD in the extracellular portion of the channel.

    Place, publisher, year, edition, pages
    NATURE PUBLISHING GROUP, 2016
    National Category
    Structural Biology
    Identifiers
    urn:nbn:se:liu:diva-130064 (URN)10.1038/srep27562 (DOI)000377343800001 ()27278891 (PubMedID)
    Note

    Funding Agencies|Swedish Research Council; Swedish Brain Foundation; Swedish Heart-Lung Foundation; Swedish e-Science Research Center; Foundation Blanceflor Boncompagni Ludovisi, nee Bildt

    Available from: 2016-07-06 Created: 2016-07-06 Last updated: 2018-04-09
  • Public defence: 2018-05-14 13:00 Bella Donna, Linköping
    Danielsson, Marita
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Patient Safety - Cultural Perspectives2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: Shared values, norms and beliefs of relevance for safety in health care can be described in terms of patient safety culture. This concept overlaps with patient safety climate, but culture represents the deeprooted values, norms and beliefs, whereas climate refers to attitudes and more superficial manifestations of culture. There may be numerous subcultures within an organization, including different professional cultures. In recent years, increased attention has been paid to patient safety culture in Sweden, and the patient safety culture/climate in health care is regularly measured based on the assumption that patient safety culture/climate can influence various patient safety outcomes.

    Aim: The overall aim of the thesis is to contribute to an improved understanding of patient safety culture and subcultures in Swedish health care.

    Design and methods: The thesis is based on four studies applying different methods. Study 1 was a survey that included 23,781 respondents. Data were analysed with quantitative methods, with primarily descriptive results. Studies 2 and 3 were qualitative studies, involving interviews with a total of 28 registered nurses, 24 nurse assistants and 28 physicians. Interview data were analysed using content analysis. Study 4 evaluated an intervention intended to influence patient safety culture and included data from a questionnaire with both fixed and open-ended questions, which was answered by 200 respondents.

    Results: A key result from Study 1 was that professional groups differed in terms of their views and statements about patient safety culture/ climate. Registered nurses and nurse assistants in Study 2 were found to have partially overlapping norms, values and beliefs concerning patient safety, which were identified at individual, interpersonal and organizational level. Study 3 found four categories of values and norms among physicians of potential relevance for patient safety. Predominantly positive perceptions were found in Study 4 concerning the Walk Rounds intervention among frontline staff members, local managers and top-level managers who participated in the intervention. However, there were also reflections on disadvantages and some suggestions for improvement.

    Conclusions: According to the results of the patient safety culture/ climate questionnaire, perceptions about safety culture/climate dimensions contribute more to the rating of overall patient safety than background characteristics (e.g. profession and years of experience). There are differences in the patient safety culture between registered nurses and nurse assistants, which imply that efforts for improved patient safety must be tailored to their respective values, norms and beliefs. Several aspects of physicians’ professional culture may have relevance for patient safety. Expectations of being infallible reduce their willingness to talk about errors they make, thus limiting opportunities for learning from errors. Walk Rounds are perceived to contribute to increased learning concerning patient safety and could potentially have a positive influence on patient safety culture.

    List of papers
    1. Patient safety subcultures among registered nurses and nurse assistants in Swedish hospital care: a qualitative study.
    Open this publication in new window or tab >>Patient safety subcultures among registered nurses and nurse assistants in Swedish hospital care: a qualitative study.
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    2014 (English)In: BMC nursing, ISSN 1472-6955, Vol. 13, no 1, p. 39-Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: Patient safety culture emerges from the shared assumptions, values and norms of members of a health care organization, unit, team or other group with regard to practices that directly or indirectly influence patient safety. It has been argued that organizational culture is an amalgamation of many cultures, and that subcultures should be studied to develop a deeper understanding of an organization's culture. The aim of this study was to explore subcultures among registered nurses and nurse assistants in Sweden in terms of their assumptions, values and norms with regard to practices associated with patient safety.

    METHODS: The study employed an exploratory design using a qualitative method, and was conducted at two hospitals in southeast Sweden. Seven focus group interviews and two individual interviews were conducted with registered nurses and seven focus group interviews and one individual interview were conducted with nurse assistants. Manifest content analysis was used for the analysis.

    RESULTS: Seven patient safety culture domains (i.e. categories of assumptions, values and norms) that included practices associated with patient safety were found: responsibility, competence, cooperation, communication, work environment, management and routines. The domains corresponded with three system levels: individual, interpersonal and organizational levels. The seven domains consisted of 16 subcategories that expressed different aspects of the registered nurses and assistants nurses' patient safety culture. Half of these subcategories were shared.

    CONCLUSIONS: Registered nurses and nurse assistants in Sweden differ considerably with regard to patient safety subcultures. The results imply that, in order to improve patient safety culture, efforts must be tailored to both registered nurses' and nurse assistants' patient safety-related assumptions, values and norms. Such efforts must also take into account different system levels. The results of the present study could be useful to facilitate discussions about patient safety within and between different professional groups.

    National Category
    Clinical Medicine Nursing
    Identifiers
    urn:nbn:se:liu:diva-115378 (URN)10.1186/s12912-014-0039-5 (DOI)25435809 (PubMedID)
    Available from: 2015-03-13 Created: 2015-03-13 Last updated: 2018-04-12
    2. Patient safety walk rounds: views of frontline staff members and managers in Sweden
    Open this publication in new window or tab >>Patient safety walk rounds: views of frontline staff members and managers in Sweden
    2015 (English)In: International Journal of Nursing, ISSN 2373-7662, Vol. 2, no 2, p. 81-93Article in journal (Refereed) Published
    Abstract [en]

    Background: Leadership Walk Rounds (WRs) have been described as a promising intervention to achieve a culture of safety by means of engaging leaders at different levels in patient safety issues. The aim was to investigate WRs carried out in a Swedish county council in terms of advantages, disadvantages and opportunities for improvement, as perceived by the participating frontline staff members, local unit managers and top-level managers.Methods: A cross-sectional study of 19 WRs. Responses from questionnaireswere analysed using qualitative and quantitative methods. Content analysis was used to categorize the findings from open-ended questions regarding advantages, disadvantages and suggestions for improvement.Results: The response rate was 95%. The participants in the WRs were generally very positive about the intervention. They believed that the intervention had several advantages and that WRs could have an impact on patient safety. Few differences between the three personnel categories were found.Conclusions: A WR developed on the basis of descriptions in the literature was perceived to have many advantages according to frontline staff members, local managers and top-level managers who participated in the intervention. WRs are perceived to contribute to increased learning concerning patient safety and to influence the patient safety culture. The overall positive findings are broadly consistent with the predominantly optimistic reports of WRs in the patient safety literature. However, further research is needed to investigate how the potential of the WR can be realized, including evaluationsof the effectiveness of the intervention in terms of various patient safety outcomes.

    Place, publisher, year, edition, pages
    American research institute for policy development, 2015
    Keyword
    Patient safety, walk rounds, patient safety culture, management
    National Category
    Health Sciences
    Identifiers
    urn:nbn:se:liu:diva-135794 (URN)10.15640/ijn.v2n2a10 (DOI)
    Available from: 2017-03-22 Created: 2017-03-22 Last updated: 2018-04-12
  • Public defence: 2018-05-18 13:00 Rosensalen, Jönköping
    Thörne, Karin
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences.
    Läkare, lärande och interaktion i hälso-och sjukvårdspraktiker2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Background: The level of complexity within healthcare services is continually increasing. These services are put under pressure by changing demographics and associated illness profiles, the influence of globalization, and the introduction of new technologies. Physicians are expected to perform and develop their daily work in cooperation with other healthcare professionals and in association with increasing levels of patient involvement. In such a changing and challenging healthcare environment, more knowledge is needed about how learning takes place and how learning can be facilitated and developed in the daily provision of healthcare services.

    Aim: The overarching aim of this dissertation is to deepen our knowledge and understanding of the pedagogic processes and the learning that takes place in healthcare practices, with particular focus on physicians’ learning.

    Methods: The research methodology employed in this dissertation includes interviews and field studies that used an interactive research approach. Authentic healthcare practices, including physicians, other care providers, patients, clinical tools in use, and the spatial arrangements within which the healthcare practices were performed were studied. The data that was collected was analyzed from a practice-theory perspective, thus allowing the researcher to identify and describe several dimensions of learning and interaction in healthcare practices.

    Results: The pedagogic processes that were identified in the physicians’ and the other healthcare practitioners’ daily work with their patients can be described as read-guide-learning support. The pedagogic dimension of this work was not immediately revealed nor was it overtly articulated. The physicians dynamically, by themselves, taught and supported the junior physicians and other healthcare providers’ learning. The physicians’ mobility in a variety of healthcare contexts was of relevance to the learning that took place. By viewing specific healthcare contexts as performing health care practices during the study, a rounds work emerged which included both (i) co-produced learning rounds and (ii) operative rounds which gave rise to limited learning. The interaction between arrangements in healthcare practices, ‘practice architectures’, and the performance of the healthcare practices actually limited the junior physicians’ learning.

    Implications of the study: A proper understanding of the learning that takes place during the daily work in the provision of healthcare – by revealing and examining the pedagogic dimensions of the work that is done – can contribute to the development of learning and learning support mechanisms. Co-produced learning healthcare practices, where each participant’s needs and contributions are taken into account, have direct implications for professional development initiatives and learning, for patient involvement in their healthcare arrangements, and for interprofessional and inter-disciplinary cooperation. Such practices also provide responsible leaders and decision-makers with the opportunity to tie in healthcare quality assurance work with the daily work that is performed by healthcare practitioners in the field. 

    List of papers
    1. Pedagogical processes in health care: an exploratory study of pedagogic work with patients and next of kin
    Open this publication in new window or tab >>Pedagogical processes in health care: an exploratory study of pedagogic work with patients and next of kin
    2009 (English)In: Education for Health, ISSN 1357-6283, E-ISSN 1469-5804, Vol. 22, no 3, p. 1-11Article in journal (Refereed) Published
    Abstract [en]

    BACKGROUND: Care and education have much in common, and work in the healthcare sector is closely associated with learning and teaching. It is felt that many in the healthcare and medical services are not aware of their pedagogic skills and how they can be developed. FRAME OF REFERENCE: Belonging to a community of practice means that you share perspectives, methods and language. OBJECTIVE: The aim is to describe the pedagogical discourse by identifying pedagogical processes and studying the staffs awareness of such processes or situations in which a pedagogical approach would be useful in their work with patients and next of kin. METHOD: A qualitative study based on individual and group interviews. The analysis is directed by grounded theory. RESULTS: The pedagogical processes varied in length and quality. Most were unplanned and were usually embedded in treatment. The pedagogical process is linear (planning, goal setting, teaching and evaluating) in an educational setting but we found that the beginning and end can be unclear and the goals can be vague or non-existent. The pedagogical process is best described using the concepts Read, Guide and Provide learning support. DISCUSSION: The pedagogical discourse in healthcare is almost silent. Data indicate that at the collective level there is very little support for professional development of pedagogical ability. Tacit knowledge may therefore remain silent even though it may be possible to formulate and describe it. CONCLUSIONS: There is a strong need to focus on the pedagogical parts of the work and to encourage and support the development of professional pedagogical knowledge.

    Place, publisher, year, edition, pages
    Carfax Publishing, 2009
    National Category
    Pedagogy
    Identifiers
    urn:nbn:se:liu:diva-56867 (URN)
    Available from: 2010-06-08 Created: 2010-06-08 Last updated: 2018-04-20
    2. The Dynamics of Physicians’ Learning and Support of Others’ Learning
    Open this publication in new window or tab >>The Dynamics of Physicians’ Learning and Support of Others’ Learning
    2014 (English)In: Professions & Professionalism, ISSN 1893-1049, E-ISSN 1893-1049, Vol. 4, no 1Article in journal (Refereed) Published
    Abstract [en]

    Learning has been defined as a condition for improving the quality of healthcare practice. The focus of this paper is on physicians’ learning and their support of others’ learning in the context of Swedish healthcare. Data were generated through individual and focus group interviews and analyzed from a socio-material practice theory perspective. During their workday, physicians dynamically alternated between their own learning and their support of others’ learning in individual patient processes. Learning and learning support were interconnected with the versatile mobility of physicians across different contexts and their participation in multiple communities of collaboration and through tensions between responsibilities in healthcare. The findings illustrate how learning enactments are framed by the existing “practice architectures.” We argue that productive reflection on dimensions of learning enactments in practice can enhance physicians’ professional learning and improve professional practice.

    Place, publisher, year, edition, pages
    Högskolan Oslo och Akershus, 2014
    Keyword
    professional practice; physicians; learning; workplace learning; practice theory; interprofessional learning
    National Category
    Medical and Health Sciences Social Sciences
    Identifiers
    urn:nbn:se:liu:diva-105998 (URN)10.7577/pp.605 (DOI)
    Available from: 2014-04-16 Created: 2014-04-16 Last updated: 2018-04-20Bibliographically approved
    3. Co-Producing Interprofessional Round Work: Designing Spaces for Patient Partnership
    Open this publication in new window or tab >>Co-Producing Interprofessional Round Work: Designing Spaces for Patient Partnership
    2017 (English)In: Quality Management in Health Care, ISSN 1063-8628, E-ISSN 1550-5154, Vol. 26, no 2, p. 70-82Article in journal (Refereed) Published
    Abstract [en]

    Within wide-ranging quality improvement agendas, patient involvement in health care is widely accepted as crucial. Ward rounds that include patients active participation are growing as an approach to involve patients, ensure safety, and improve quality. An emerging approach to studying quality improvement is to focus on "clinical microsystems," where patients, professionals, and information systems interact. This provides an opportunity to study ward rounds more deeply. A new model of conducting ward rounds implemented through quality improvement work was studied, using the theory of practice architectures as an analytical tool. Practice architecture focuses on the cultural-discursive, social-political, and material-economic conditions that shape what people do in their work. Practice architecture is a sociomaterial theoretical perspective that has the potential to change how we understand relationships between practice, learning, and change. In this study, we examine howchanges in practices are accomplished. The results show that practice architecture formed co-productive learning rounds, a possible model integrating quality improvement in daily work. This emerged in the interplay between patients through their " double participation" (as people and as information on screens), and groups of professionals in a ward round room. However, social interplay had to be renegotiated in order to accomplish the goals of all ward rounds.

    Place, publisher, year, edition, pages
    LIPPINCOTT WILLIAMS & WILKINS, 2017
    Keyword
    clinical microsystem; co-production; practice architectures; sociomaterial practice theory; quality improvement; ward round; workplace learning
    National Category
    Social Sciences Interdisciplinary
    Identifiers
    urn:nbn:se:liu:diva-137402 (URN)10.1097/QMH.0000000000000133 (DOI)000399390400003 ()28375953 (PubMedID)
    Available from: 2017-05-18 Created: 2017-05-18 Last updated: 2018-04-20
  • Public defence: 2018-05-18 13:00 sal I:101, Hus I, LinköpingColliander, Helena
    Being and Becoming a Teacher in Initial Literacy and Second Language Educationfor Adults2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The aim of the thesis is to explore what being and becoming a teacher of Literacy Education and Second Language Learning for Adults (LESLLA) mean. The study, which applies situated learning theory combined with some Bourdieuan concepts as thinking tools, seeks to depict how the professional identity of LESLLA teachers can be understood from their memberships in different communities of practice. The empirical study is based on observational data and on semi-structured interviews, which have been analysed thematically. The results show that the LESLLA teachers construct professional identity in regard to the particular nature of the learners, i.e. that the learners are simultaneously adult emergent readers and second language learners establishing themselves in a new society. This is, for example, seen in the teachers’ teaching actions and in how they respond to learning opportunities and changes. Likewise, the results illustrate that becoming a LESLLA teacher is an ongoing process in which some periods are particularly critical for learning. It takes place in a number of different communities of which the teaching practices are the most crucial. When it comes to the other communities to which the teachers belong, their significance differs from teacher to teacher. Moreover, power plays a central role in the identity formation. Societal forces, and the position and trajectory of the teacher in different communities in the landscapes of LESLLA teaching and Swedish for Immigrants (SFI) contribute to it.

    List of papers
    1. The experienced newcomer - The (trans)forming of professional teacher identity in a new landscape of practices
    Open this publication in new window or tab >>The experienced newcomer - The (trans)forming of professional teacher identity in a new landscape of practices
    2018 (English)In: Teaching and Teacher Education: An International Journal of Research and Studies, ISSN 0742-051X, E-ISSN 1879-2480, Vol. 69, p. 168-176Article in journal (Refereed) Published
    Abstract [en]

    n/a

    Place, publisher, year, edition, pages
    PERGAMON-ELSEVIER SCIENCE LTD, 2018
    National Category
    Educational Sciences
    Identifiers
    urn:nbn:se:liu:diva-144138 (URN)10.1016/j.tate.2017.10.012 (DOI)000418218200016 ()
    Available from: 2018-01-10 Created: 2018-01-10 Last updated: 2018-04-20
    2. Building bridges and strengthening positions: Exploring the identity construction of immigrant bilingual teachers
    Open this publication in new window or tab >>Building bridges and strengthening positions: Exploring the identity construction of immigrant bilingual teachers
    2017 (English)In: International Journal of Bilingual Education and Bilingualism, ISSN 1367-0050, E-ISSN 1747-7522Article in journal (Refereed) Published
    Abstract [en]

    This study explores how bilingual teachers with an immigrant background construct professional identity in the context of initial literacy and second language teaching of adults. Specifically, the study seeks to understand what the teachers’ membership of different work-related communities means for their professional identity and what capital the teachers use, negotiate and acquire to strengthen their positions in this professional field. The study is based on interviews with seven bilingual teachers. The data has been analysed from the perspective of situated learning theory and by employing some complementing concepts of Bourdieu used as thinking tools. The findings illustrate how the teachers construct their professional identity in relation to their students and by positioning themselves in different teacher communities. Moreover, the findings stress how the local school community plays a crucial part in determining the position the teachers obtain in the field. But in spite of being acknowledged as professionals, the teachers still need to negotiate their position by acquiring new capital and stressing the capital they already have.

    Place, publisher, year, edition, pages
    Routledge, 2017
    Keyword
    Bilingual teachers, professional identity construction, bilingual education, mother tongue education, Literacy Education and Second Language Learning for Adults (LESLLA)
    National Category
    General Language Studies and Linguistics
    Identifiers
    urn:nbn:se:liu:diva-144866 (URN)10.1080/13670050.2017.1400516 (DOI)2-s2.0-85033404544 (Scopus ID)
    Available from: 2018-02-05 Created: 2018-02-05 Last updated: 2018-04-20Bibliographically approved
  • Public defence: 2018-05-25 09:00 Berzeliussalen, Linköping
    Söderlund Schaller, Anne
    Linköping University, Department of Medical and Health Sciences, Division of Community Medicine. Linköping University, Faculty of Medicine and Health Sciences. Region Östergötland, Anaesthetics, Operations and Specialty Surgery Center, Pain and Rehabilitation Center.
    Impact of Pain and Evaluation of Education and Self-Care in Patients with Head and Neck Cancer2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    It is not unusual for patients with head and neck cancer (HNC) to suffer from both tumor and treatment-related pain that is difficult to alleviate despite individualized pharmacological treatment.

    The presence of concomitant various dimensions of pain in patients during the often difficult period following radiotherapy (RT) has not been elucidated. Several aspects concerning the importance of relatives for HNC patients have been addressed. However, little attention has been given to how relatives perceive patients with HNC pain and it is important to further elucidate this sparsely studied topic. Knowledge about health-related quality of life (HR-QoL) in this patient group during early RT is limited and needs to be assessed in relation to diagnosis and treatment. Self-care (SC) refers to what patients do on their own to achieve, maintain, and promote optimal health and may help reduce pain for several pain conditions. The impact of patient education and SC on pain and other common HNC symptoms need further clarification.

    The aims of this thesis were:

    1. to describe experiences and perceptions of pain in patients with HNC shortly after RT
    2. to describe how relatives perceived the patient’s situation, especially concerning pain, and how they experienced their own situation
    3. to identify factors that impact HR-QoL during early RT
    4. to develop effective pain management strategies, maintain activities of daily living, and promote HR-QoL in patients with HNC undergoing RT using patient education and SC instruction.

    In paper I patients with HNC described existential pain – expressed as fear of death, meaninglessness and guilt – already during and shortly after RT. Physical pain, psychological distress and social withdrawal played a significant role. Patients with HNC who were treated with RT should also proactively be offered treatment for the various dimensions of pain.

    In paper II relatives described their mental stress in response to a challenging situation that required their active support to help ease the patient's difficult condition. The interviews with relatives also revealed a lack of personal knowledge and frustration over the inability to participate in patient care, as well as inadequate support from the healthcare system. Early interventions from the healthcare system on behalf of the relatives may be necessary to meet these needs.

    In Paper III regression models revealed that pain intensity and symptoms of depression adversely affected HR-QoL in patients with HNC during early RT. Customized prehabilitation programs aimed at preventing pain and symptoms of depression could help preserve good HR-QoL.

    Paper IV assessed individual patient education and SC initiatives that resulted in a tendency for lower pain intensity during a portion of RT. One way to potentially enhance the benefits of education and SC could be to improve for example patient motivation and self-efficacy, as well as to optimize supportive efforts from caregivers.

    In conclusion, by identifying factors that can impact HR-QoL and evaluating the effect of patient education and SC, this thesis contributes to knowledge on perceived pain and the patient’s situation during and shortly after RT in patients with HNC and their relatives. This thesis points to the need for evaluation and further development of patient education and effective SC strategies for pain in patients with HNC undergoing RT, as well as for development and evaluation of support strategies for patients with pain and their families during and after RT.

    List of papers
    1. Experiences of Pain: A Longitudinal, Qualitative Study of Patients with Head and Neck Cancer Recently Treated with Radiotherapy
    Open this publication in new window or tab >>Experiences of Pain: A Longitudinal, Qualitative Study of Patients with Head and Neck Cancer Recently Treated with Radiotherapy
    2015 (English)In: Pain Management Nursing, ISSN 1524-9042, E-ISSN 1532-8635, Vol. 16, no 3, p. 336-345Article in journal (Refereed) Published
    Abstract [en]

    It is not unusual for patients with head and neck cancer (HNC) to suffer from both tumor- and treatment-related pain that is difficult to alleviate despite individualized pain management. The aim of this qualitative study was to describe how HNC patients experience pain and how pain influences those who are treated with radiotherapy (RT). Qualitative semistructured interviews were performed 1 and 6 months after patients completed RT. The interviews addressed symptoms, moods, and suffering. The study included 26 patients with HNC who had recently completed RT. The interviews were analyzed using manifest content analysis. The main category was: HNC patients did not report that their severe physical pain influenced their psychological suffering, but it did influence their social lives. Furthermore, four categories were revealed: pain in the head and neck region, overwhelming fatigue, altered mood and preoccupied mind, and decreased participation and changed relationships. Physical pain, psychological distress, and social withdrawal were prominent at both interviews and consequently their situation can be considered as chronic. Remarkably, patients did not express a clear relationship between pain and psychological load. This may imply a biomedical view of pain or may reflect the difficult situation patients were in (i.e., facing a possibly life-threatening cancer). Thus, their situation might require a prioritization and might negatively affect the possibility of identifying the interaction between the different pain dimensions. The biopsychosocial model of chronic pain aims to understand the interaction between pain and psychosocial factors. Interventions aiming to teach patients with HNC how to internalize the biopsychosocial model framework to manage pain could be useful and should be evaluated in future research.

    National Category
    Basic Medicine
    Identifiers
    urn:nbn:se:liu:diva-115363 (URN)10.1016/j.pmn.2014.08.010 (DOI)000355212500022 ()25532691 (PubMedID)
    Available from: 2015-03-13 Created: 2015-03-13 Last updated: 2018-04-13
    2. How relatives of patients with head and neck cancer experience pain, disease progression and treatment: A qualitative interview study
    Open this publication in new window or tab >>How relatives of patients with head and neck cancer experience pain, disease progression and treatment: A qualitative interview study
    2014 (English)In: European Journal of Oncology Nursing, ISSN 1462-3889, E-ISSN 1532-2122, Vol. 18, no 4, p. 405-410Article in journal (Refereed) Published
    Abstract [en]

    Purpose: This study of relatives to patients with head and neck cancer (HNC) treated with radiotherapy describes how the relatives experienced the patients situation, especially with respect to pain, and how the relatives themselves experienced the situation. Methods: Semi-structured interviews of 21 relatives to HNC patients who suffered from pain were conducted, and a qualitative content analysis was performed. Results: The relatives experienced that the patients suffered from physical, psychological, and social pain. A dark picture consisting of lack of participation and knowledge, psychological distress, and lack of support were reported. Thus, a main category: relatives struggle with loved ones pains related to head and neck cancer treatment and with their own demanding situation - was based on the following four categories: inability to relieve and comprehend the physical suffering of the patients; overwhelming emotions were experienced that affect the patients and the relatives themselves; in need of support from the health care service; and altered daily activities and family roles due to illness and treatment. Conclusion: In patients physical, psychological, and social pain were prominent and in relatives psychological distress, lack of knowledge and support were experienced. Thus, to reduce pain and anxiety in patients and relatives, the health care professionals should provide relevant knowledge about pain management. The health care professionals should also provide educational interventions that address the psychological and social factors that impact pain for HNC patients and their relatives. Well-thought supporting care and easily accessible information about practical concerns should be offered to HNC patients and their relatives.

    Place, publisher, year, edition, pages
    Elsevier, 2014
    Keyword
    Head and neck cancer; Relatives; Pain; Qualitative content analysis; Interviews
    National Category
    Sociology Basic Medicine
    Identifiers
    urn:nbn:se:liu:diva-109583 (URN)10.1016/j.ejon.2014.03.008 (DOI)000339533600010 ()24726013 (PubMedID)
    Available from: 2014-08-21 Created: 2014-08-21 Last updated: 2018-04-13
    3. Quality of life during early radiotherapy in patients with head and neck cancer and pain
    Open this publication in new window or tab >>Quality of life during early radiotherapy in patients with head and neck cancer and pain
    2017 (English)In: Journal of Pain Research, ISSN 1178-7090, E-ISSN 1178-7090, Vol. 10, p. 1697-1704Article in journal (Refereed) Published
    Abstract [en]

    Background: Patients with head and neck cancer (HNC) have a potentially severe diagnosis and often suffer from tumor-related pain as well as from adverse side effects of treatment such as radiotherapy (RT). Knowledge about quality of life (QoL) during early RT in this group is limited and should be assessed in relation to diagnosis and treatment. Purpose: The purpose of this cross-sectional study was to identify potential factors that may influence QoL in patients with HNC during the early stages of RT (no later than two weeks of ongoing RT). We hypothesized that pain intensity, pain interference, catastrophizing, and mood disturbances are associated with QoL during early RT. Patients and methods: In this study, 54 patients (53% of eligible patients) diagnosed with HNC were consecutively recruited from the regular flow to the Pain and Rehabilitation Center at Linkoping University. The patients completed self-reported questionnaires on sociodemo-graphics, pain intensity, pain interference, anxiety, depression, pain catastrophizing, and QoL. Results: The patients in this study scored high for QoL, low for pain intensity, and low for pain interference. The patients reported minor depressive symptoms and anxiety symptoms. Regression analyses showed that pain intensity and depressive symptoms negatively influenced QoL. Conclusion: No later than two weeks of RT, pain intensity and depression negatively influenced QoL in patients with HNC. Early screening for pain and depression in a targeted preventive strategy might maintain QoL during the course of the RT for patients with HNC. This assumption needs to be further investigated.

    Place, publisher, year, edition, pages
    DOVE MEDICAL PRESS LTD, 2017
    Keyword
    pain; quality of life; head and neck cancer; radiotherapy; cross-sectional study
    National Category
    Physiotherapy
    Identifiers
    urn:nbn:se:liu:diva-139653 (URN)10.2147/JPR.S138113 (DOI)000405597700005 ()28761374 (PubMedID)
    Available from: 2017-08-16 Created: 2017-08-16 Last updated: 2018-04-13
  • Public defence: 2018-05-25 13:00 Key 1, Hus Key, Linköping
    Daugaard, Solveig
    Linköping University, Department of Culture and Communication, Language and Literature. Linköping University, Faculty of Arts and Sciences.
    Collaborating with Gertrude Stein: Media ecologies, reception, poetics2018Doctoral thesis, monograph (Other academic)
    Abstract [en]

    The reception of the American avant-garde poet, playwright, art collector and salon hostess Gertrude Stein (1874-1946) has to a wide extent taken place in an aesthetic context prior to her work’s academic and hermeneutic canonization. This thesis is in part a mapping of this transmedia reception as it is played out in a North American context in the period from her death and until today, and in part an account of Stein’s particular collaborative poetics, through which her work invites such a reception. Furthermore, the thesis maintains that we in a contemporary context are experien­cing a still increasing receptivity towards Stein’s oeuvre, that seems more relevant today than ever before.  

    These circumstances, the thesis illuminates and discusses via a media theoretical framework, where Stein’s own work, as well as its aesthetic reception is considered as embedded in a complex media ecology. Media ecology is here conceived as a de­centralized, networked approach to aesthetic phenomena, which is able to contain many types of agents and materialities. The media ecology of an artwork is thus po­tentially made up by the entire network of processes, agents and materials that are relevant to its production, distribution and consumption and influences the subject positions available to the individual agents.

    Through Stein’s aesthetic reception it is possible to catch sight of important compo­nents that are active in the media ecology but often neglected or considered subor­dinated to text-internal features. These include the material interface of the medium in question, the aestheticized persona of the artist and infrastructures such as the salon, which affect how and to whom the work and its meanings are distributed. The thesis also traces a number of parallels between the media situation of Stein in the beginning of the 20th century and the digital media situation at the verge of the 21st that suggest both explanations for and implications of her increasing contemporary relevance.

  • Public defence: 2018-05-29 13:18 Planck, Fysikhuset, Linköping
    Atakan, Aylin
    Linköping University, Department of Physics, Chemistry and Biology, Nanostructured Materials. Linköping University, Faculty of Science & Engineering.
    Mesoporous material systems for catalysis and drug delivery2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Hybrid material systems possess multi-functional properties which make them intriguing for the materials science community since very early dates. However, it is not straightforward to produce such material systems. A smart and efficient approach is necessary to extract the desired properties of each component under the desired conditions. This study evolved to its last form primarily around this notion, where the development of a hybrid material is the core of the work. This hybrid material is then further explored for two different applications in the catalysis and drug delivery fields.

    A nanoassembly was established around a mesoporous silica support. SBA-15 was picked as this support among the other mesoporous silica due to its well-defined pore structure and accessible pore volume. The silica framework was doped with Zr atoms and the pores were partly infiltrated with Cu nanoparticles resulting in a hybrid material with tunable properties. SBA-15 was synthesized by a sol-gel method where a micellar solution was employed as a template for the silica framework. To achieve the doped version, a Zr precursor was added to the synthesis solution. The effects of different synthesis conditions, such as the synthesis catalyst (F-or a Cl-salt) and the Si source (tetraethyl orthosilicate (TEOS) or sodium metasilicate (SMS)) on the characteristics of the final material were investigated. It was observed that these changes in the synthesis conditions yielded different particle morphology, pore size (11-15 nm), and specific surface area (400-700 m2/g). Cu nanoparticles (NPs) were grown in the (Zr-)SBA-15 support using infiltration (Inf) or evaporation induced wetness impregnation (EIWI) methods. The infiltration method is based on functionalizing the (Zr-)SBA-15 support surfaces before the Cu ion attachment whereas EIWI is based on slow evaporation of the liquid from the (Zr-)SBA-15 - Cu aqueous suspension. Both methods are designed to yield preferential growth of Cu NPs in the pores with a diameter smaller than 10 nm and in oxidized form. However, depending on the loading method used, different chemical states of the final material were achieved, i.e. Zr content and porous network properties are different. 

    Cu-Zr-SBA-15 nanoassemblies produced under various synthesis conditions were used for the catalytic conversion of CO2into valuable fuels such as methanol and dimethyl ether (DME). The effect of different chemical states of the catalyst arising from variations in the synthesis parameters was investigated. It was found that the Si precursor (TEOS or SMS) had a considerable impact on the overall performance of the catalyst whereas the Cu loading method (Inf or EIWI) changed the catalytic selectivity between DME and methanol. The activity of the catalyst was further investigated in a time-evolution study where the accumulation of each product in the gas phase and the molecular groups attached to the catalyst surface were recorded over time. Accordingly, thermodynamic equilibrium was achieved on the 14th day of the reaction under 250°C and 33 bar. The resulting total CO2conversion was 24%, which is the thermodynamically highest possible conversion, according to theoretical calculations. It was also concluded from the experimental results that, DME is formed by a combination of two methoxy surface groups. Additionally, the formation of DME boosts the total CO2conversion to fuels, which otherwise is limited to 9.5%.

    The design of Cu-Zr-SBA-15 was also investigated for drug delivery applications, due to its potential as a biomaterial, e.g., a filler in dental composites, and the antibacterial properties of Cu. Also, the bioactivity of SiO2and ZrO2was considered to be an advantage. With this aim, Cu infiltrated Zr doped SBA-15 material was prepared by using TEOS as the silica precursor and the Inf-method to grow Cu NPs. The performance of the final material as a drug delivery vehicle was tested by an in-vitro delivery study with chlorhexidine digluconate.The nanoassemblies show a drug loading capacity of 25-40% [mg drug / mg (drug+carrier)]. The drug release was determined to be composed of two steps. First, a burst release of the drug molecules that are loosely held in the voids of the mesoporous carrier followed by the diffusion of the drug molecules that are attached to the carrier surface. The presence of Zr and Cu limits the burst release and beneficially slows down the drug release process. 

    The effect of pore properties of SBA-15 was explored in a study where the antibiotic doxycycline hyclate was loaded in SBA-15 materials with different pore sizes. It was observed that the pore size is directly proportional to the drug loading capacity [mg drug / mg (drug+carrier)] and the released drug percentage (the released drug amount/total amount of loaded drug). The drug release was fast due to its weak interactions with the SBA-15 materials. 

    In summary, this work demonstrates the multifunctional character of a smart-tailored nanoassembly which gives valuable insights for two distinct applications in catalysis and drug delivery.

    List of papers
    1. Synthesis of a Cu-infiltrated Zr-doped SBA-15 catalyst for CO2 hydrogenation into methanol and dimethyl ethert
    Open this publication in new window or tab >>Synthesis of a Cu-infiltrated Zr-doped SBA-15 catalyst for CO2 hydrogenation into methanol and dimethyl ethert
    Show others...
    2017 (English)In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 19, no 29, p. 19139-19149Article in journal (Refereed) Published
    Abstract [en]

    A catalytically active nanoassembly comprising Cu-nanoparticles grown on integrated and active supports (large pore Zr-doped mesoporous SBA-15 silica) has been synthesized and used to promote CO2 hydrogenation. The doped mesoporous material was synthesized using a sal-gel method, in which the pore size was tuned between 11 and 15 nm while maintaining a specific surface area of about 700 m(2) g (1). The subsequent Cu nanoparticle growth was achieved by an infiltration process involving attachment of different functional groups on the external and internal surfaces of the mesoporous structure such that 7-10 nm sized Cu nanoparticles grew preferentially inside the pores. Chemisorption showed improved absorption of both CO2 and H-2 for the assembly compared to pure SBA-15 and 15% of the total CO2 was converted to methanol and dimethyl ether at 250 degrees C and 33 bar.

    Place, publisher, year, edition, pages
    ROYAL SOC CHEMISTRY, 2017
    National Category
    Materials Chemistry
    Identifiers
    urn:nbn:se:liu:diva-139804 (URN)10.1039/c7cp03037a (DOI)000406334300033 ()28702581 (PubMedID)
    Note

    Funding Agencies|EUs Erasmus-Mundus program; Swedish Research Council; Swedish Government Strategic Research Area in Materials Science on Functional Materials at Linkoping University [SFO-Mat-LiU 11 2009-00971]; Knut och Alice Wallenbergs Foundation [KAW 2012.0083]

    Available from: 2017-08-17 Created: 2017-08-17 Last updated: 2018-04-16
    2. Time evolution of the CO2 hydrogenation to fuels over Cu-Zr-SBA-15 catalysts
    Open this publication in new window or tab >>Time evolution of the CO2 hydrogenation to fuels over Cu-Zr-SBA-15 catalysts
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    2018 (English)In: Journal of Catalysis, ISSN 0021-9517, E-ISSN 1090-2694, Vol. 362, p. 55-64Article in journal (Refereed) Published
    Abstract [en]

    Time evolution of catalytic CO2 hydrogenation to methanol and dimethyl ether (DME) has been investigated in a high-temperature high-pressure reaction chamber where products accumulate over time. The employed catalysts are based on a nano-assembly composed of Cu nanoparticles infiltrated into a Zr doped SiOx mesoporous framework (SBA-15): Cu-Zr-SBA-15. The CO2 conversion was recorded as a function of time by gas chromatography-mass spectrometry (GC-MS) and the molecular activity on the catalyst’s surface was examined by diffuse reflectance in-situ Fourier transform infrared spectroscopy (DRIFTS). The experimental results showed that after 14 days a CO2 conversion of 25% to methanol and DME was reached when a DME selective catalyst was used which was also illustrated by thermodynamic equilibrium calculations. With higher Zr content in the catalyst, greater selectivity for methanol and a total 9.5% conversion to methanol and DME was observed, yielding also CO as an additional product. The time evolution profiles indicated that DME is formed directly from methoxy groups in this reaction system. Both DME and methanol selective systems show the thermodynamically highest possible conversion.

    Keyword
    Cu-Zr-SBA-15, CO2 hydrogenation, Catalysis, Time evolution, Thermodynamics, Methanol, Dimethyl ether
    National Category
    Nano Technology Physical Chemistry
    Identifiers
    urn:nbn:se:liu:diva-147297 (URN)10.1016/j.jcat.2018.03.023 (DOI)
    Available from: 2018-04-16 Created: 2018-04-16 Last updated: 2018-04-16Bibliographically approved
  • Public defence: 2018-06-07 13:15 TemCAS, Tema-huset, Linköping
    Parks, Darcy
    Linköping University, Department of Thematic Studies, Technology and Social Change. Linköping University, Faculty of Arts and Sciences.
    The Sustainable City Becomes Climate-Smart: How Smart City Ideas Reshape Urban Environmental Governance2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    The idea of smart cities has become enormously popular during the past decade. Environmental governance is one issue in which smart city ideas seem to hold potential. However, there is an incredible variety in what it means for a city to be ‘smart’. For some, it involves the use of information and communication technology (ICT) to solve problems; for others, it has more to do with economic growth and city branding. Many social science researchers have criticised the idea of smart cities. They worry that it might allow multinational corporations to take control of municipal governance and lead to an undue focus on technological solutions to societal issues. However, only a few previous studies have examined the influence on urban environmental governance in practice. This thesis investigates the influence of smart city ideas on urban environmental governance through a study of Hyllie, a climate-smart city district in Malmö, Sweden. It applies a theoretical perspective based on science and technology studies and the concept of assemblage. It combines participant-observation of inter-organisational meetings, interviews with professionals and document analysis. This thesis contributes a more comprehensive picture of which actors influence the direction of the climate-smart city—beyond the usual suspects of municipal governments and multinational companies. Still, it shows how ICT-based smart city solutions have taken precedence in urban environmental governance at the expense of energy efficiency and renewable energy.

    List of papers
    1. Energy efficiency left behind? Policy assemblages in Sweden’s most climate-smart city
    Open this publication in new window or tab >>Energy efficiency left behind? Policy assemblages in Sweden’s most climate-smart city
    2018 (English)In: European Planning Studies, ISSN 0965-4313, E-ISSN 1469-5944Article in journal (Refereed) Epub ahead of print
    Abstract [en]

    Smart city experiments have the potential to reshape urban climate change governance. Smart city initiatives have been supported by international technology companies and the European Union for many years and continue to be promoted by national and municipal governments. In relation to sustainability and climate change, such initiatives promise more efficient use of resources through the use of information and communications technology in energy infrastructure. Experiments with smart city technologies such as urban smart grids have shown the potential to restructure relationships between energy utilities, energy users and other actors by reconfiguring the dynamics of energy supply and demand. But do urban experiments lead to institutional change? The aim of the article is to provide a better understanding of how smart city experiments reshape the urban governance of building energy use. Hyllie, a new city district in Malmö, Sweden, was home to two smart city experiments that contributed to the institutionalization of urban smart grid technology. However, the analysis of Hyllie’s policy assemblages shows that this institutional change could redefine sustainability at the expense of energy efficiency.

    Keyword
    Smart cities, smart grids, urban governance, urban experimentation, sustainable buildings, assemblage
    National Category
    Social Sciences Interdisciplinary
    Identifiers
    urn:nbn:se:liu:diva-147300 (URN)10.1080/09654313.2018.1455807 (DOI)
    Available from: 2018-04-16 Created: 2018-04-16 Last updated: 2018-04-16