| 1. |
- Amirahmadi, Ali, 1994-, et al.
(författare)
-
A Masked Language Model for Multi-Source EHR Trajectories Contextual Representation Learning
- 2023
-
Ingår i: Caring is Sharing - Exploiting the Value in Data for Health and Innovation - Proceedings of MIE 2023. - Amsterdam : IOS Press. - 1879-8365 .- 0926-9630. - 9781643683881 ; 302, s. 609-610, s. 609-610
-
Konferensbidrag (refereegranskat)abstract
- Using electronic health records data and machine learning to guide future decisions needs to address challenges, including 1) long/short-term dependencies and 2) interactions between diseases and interventions. Bidirectional transformers have effectively addressed the first challenge. Here we tackled the latter challenge by masking one source (e.g., ICD10 codes) and training the transformer to predict it using other sources (e.g., ATC codes).
|
|
| 2. |
|
|
| 3. |
|
|
| 4. |
- Arvidson, Johan, et al.
(författare)
-
Medical follow-up visits in adults 5-25 years after treatment for childhood acute leukaemia, lymphoma or Wilms' tumour
- 2006
-
Ingår i: Acta Paediatrica. - : Wiley. - 0803-5253 .- 1651-2227. ; 95:8, s. 922-928
-
Tidskriftsartikel (refereegranskat)abstract
- Aim: One aspect of organizing medical follow-up for adult survivors of childhood cancer is to determine to what extent the former patient experiences a need for health services. In the present paper, we studied how the healthcare needs, both subjectively and objectively, were fulfilled for our former patients. Methods: 335 survivors over 18 y of age, with a follow-up time of more than 5 y after completion of therapy, were sent a questionnaire probing their present use of health services. Results: The response rate was 73%. A majority ( 60%) of the survivors had no regular follow-up visits, and 42% of these reported that they missed not having one. More than one third were thus far dissatisfied with the follow-up programme. Only 3% of those who had regular follow-ups found them "unnecessary''. Complaints subjectively related to their diseases or treatments were reported by 47%. Out of all responders, 34% did not miss having regular follow-up visits. Neither perceived disease-related complaints nor radiation therapy was a predictor for having a scheduled follow-up visit.
|
|
| 5. |
- Björk, Oscar, 1990-, et al.
(författare)
-
Barn skriver historia: En studie av fjärdeklassares skrivande i historieämnet
- 2020
-
Ingår i: Nordidactica. - Karlstad : CSD Karlstad. - 2000-9879. ; 10:2020:2, s. 73-106
-
Tidskriftsartikel (refereegranskat)abstract
- In this study we analyze subject specific content in texts written in history education in school year 4 in a Swedish context. The study employs two different approaches to (text) content analysis: Analysis of representation of an historic vis-à-vis a practical perspective on the past, and analysis of the specific linguistic construals of the texts, based on a systemic functional linguistics approach. The results from the analyses are then compared to enable a synergetic account of the specific linguistic fabrics of the two historical perspectives. The results show that there are key differences in how the historical vis-à-vis the practical perspective on the past are linguistically construed, thus highlighting the intricacies of writing in history education. These findings are significant for researchers and teachers interested in furthering emergent historical literacy in early school years.
|
|
| 6. |
- Björk, Per, 1978-
(författare)
-
Biological Sensing and DNA Templated Electronics Using Conjugated Polymers
- 2007
-
Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Conjugated polymers have been found useful in a wide range of applications such as solar cells, sensor elements and printed electronics, due to their optical and electronic properties. Functionalization with charged side chains has enabled water solubility, resulting in an enhanced interaction with biomolecules. This thesis focus on the emerging research fields, where these conjugated polyelectrolytes (CPEs) are combined with biomolecules for biological sensing and DNA nanowire assembling.CPEs have shown large potential in biomolecular detection where the optical read out is due to the geometrical alternation in the backbone and aggregation state. This thesis focused on transferring the biomolecular detection to a surface of CPEs. The characterization of the CPE layer show that a hydrogel can be formed, and how the layer can undergo geometrical changes upon external stimulus such as pH change. A selective sensor surface can be created by imprinting ssDNA or an antibody in the CPE layer. The discrimination for complementary DNA hybridization and specific antibody interaction can be monitored by surface plasmon resonance or quartz crystal microbalance. We have also taken the step out from the controlled test tube experiments to the complex environment of the cell showing the potential for staining of compartments and structures in live and fixed cell. Depending on the conditions and CPE used, cell nuclei, acidic vesicles and cytoskeleton structure can be visualized. Furthermore, the live staining shows no sign of toxic effect on cultured fibroblasts.CPEs can also be a valuable element when assembling electronics in the true nano regime. I have used DNA as building template due to its attractive size features, with a width of around 2 nm and a length scale in the µm regime, and the inbuilt base-paring recognition elements. This thesis shows how DNA can be decorated with CPEs and stretched on surfaces into a model for aligned semiconducting nanowire geometries. Not only making the template structures is of importance, but also how to place them on the correct surface position, i.e. on electrodes. Strategies for positioning DNA nanowires using transfer printing and surface energy patterning methods have therefore been developed in the thesis. The stretched DNA decorated with CPE also offers a way to further study the molecular binding interaction between the two molecules. Single molecular spectroscopy in combination with polarization has given information of the variation of the CPE binding along a DNA chain.
|
|
| 7. |
- Björk, Per, et al.
(författare)
-
Biomolecular nanowires decorated by organic electronic polymers
- 2010
-
Ingår i: JOURNAL OF MATERIALS CHEMISTRY. - : Royal Society of Chemistry (RSC). - 0959-9428 .- 1364-5501. ; 20:12, s. 2269-2276
-
Tidskriftsartikel (refereegranskat)abstract
- We demonstrate the shaping and forming of organic electronic polymers into designer nanostructures using biomacromolecules. In order to create nanowires, nanohelixes and assemblies of these, we coordinate semiconducting or metallic polymers to biomolecular polymers in the form of DNA and misfolded proteins. Optoelectronic and electrochemical devices utilizing these shaped materials are discussed.
|
|
| 8. |
- Björk, Per, et al.
(författare)
-
Conjugated polythiophene probes target lysosome-related acidic vacuoles in cultured primary cells
- 2007
-
Ingår i: Molecular and Cellular Probes. - : Elsevier BV. - 0890-8508. ; 21:5-6, s. 329-337
-
Tidskriftsartikel (refereegranskat)abstract
- Conformation-sensitive optical probes for studying biological processes and structures are of great interest. The present work shows for the first time that conjugated polyelectrolyte (CPE) probes can be used for specific targeting of chromatin, nuclear and cytoplasmatic vesicles, and cytoskeletal components in a complex system of cultured cells. One of the probes could also be used for vital staining of live cells. When bound to different entities, the polythiophene derivative probes emitted light with different colors due to the unique spectral properties of these conformation sensitive probes. The physical pre-requisites for binding could also be exploited for characterization of the target. Unexpectedly, lysosome-related acidic vacuoles were targeted in cultured primary cells by both anionic, cationic, and zwitter-ionic polythiophene derivatives. Pre-treatment with Bafilomycin A1, a specific inhibitor of vacuolar-type H+-ATPase, caused redistribution of the staining. The targeting of lysosome-related acidic vesicles could not be demonstrated in transformed cells (melanoma, neuroblastoma, and prostate cancer cell lines), indicating a difference in the localization, structure, accessibility, or quantity of the target in cultured normal cells as compared with the malignant cell lines. The chemical nature of the conjugated polyelectrolyte complex in the cytoplasmatic vacuoles remains elusive.
|
|
| 9. |
- Björk, Per, et al.
(författare)
-
Dynamics of complex formation between biological and luminescent conjugated polyelectrolytes - a surface plasmon resonance study
- 2005
-
Ingår i: Biosensors and Bioelectronics. - : Elsevier BV. - 0956-5663. ; 20:9, s. 1764-1771
-
Tidskriftsartikel (refereegranskat)abstract
- A water-soluble polythiophene, POWT, with zwitterionic peptide like side chains possess good characteristics for biosensor applications. The zwitterionic side chains of the polymer can couple to biomolecules via electrostatic and hydrogen bonding. This creates possibilities to imprint biomolecules to spin-coated polymer films with maintained functionality, and use the resulting matrix as a biosensor. Polymer-biomolecular interaction studies done with surface plasmon resonance (SPR) reveal a well performing sensor matrix with high affinity for DNA hybridizations as well as for protein detection. The responses are distinct and very specific. A directional dependence of antibodies binding to POWT layer has also been observed. The polymer films have also been characterized by optical methods. Emission and absorption measurements in different buffer systems confirm that the polymer matrix can undergo structural and conformational changes on surfaces. The dielectric function in the interval 300–800 nm of POWT is reported, based on variable angle spectroscopic ellipsometry. This modeling reveals that a considerable amount of water is included in the material. The polymer layer possesses the characteristics needed for biochip applications and micro array techniques.
|
|
| 10. |
- Björk, Per, et al.
(författare)
-
Oligothiophene Assemblies Defined by DNA Interaction : From Single Chains to Disordered Clusters
- 2009
-
Ingår i: SMALL. - : Wiley. - 1613-6810 .- 1613-6829. ; 5:1, s. 96-103
-
Tidskriftsartikel (refereegranskat)abstract
- The organization of conjugated polyelectrolytes (CPEs) interacting with biomolecules sets conditions for the biodetection of biological processes and identity, through the use of optical emission from the CPE. Herein, a well-defined CPE and its binding to DNA is studied. By using dynamic light scattering and circular dichroism spectroscopy, it is shown that the CPE forms a multimolecule ensemble in aqueous solution that is more than doubled it? size when interacting with a small DNA chain, while single chains are evident in ethanol. The related changes in the fluorescence spectra upon polymer aggregation are assigned to oscillator strength redistribution between vibronic transitions in weakly coupled H-aggregates. An enhanced single-molecule spectroscopy technique that allows full control of excitation and emission light polarization is applied to combed and decorated;,DNA chains. It is found that the organization of combed CPE-lambda DNA complexes (when dry on the surface) allows considerable variation of CPE distances and direction relative to the DNA chain. By analysis of the polarization data. energy transfer between the polymer chains in individual complexes is confirmed and their sizes estimated.
|
|
