| 1. |
- Bergkvist, Magnus, et al.
(författare)
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A method for studying protein orientation with atomic force microscopy using relative protein volumes
- 2001
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Ingår i: Journal of Physical Chemistry B. - : American Chemical Society (ACS). - 1520-6106 .- 1520-5207. ; 105:10, s. 2062-2069
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Tidskriftsartikel (refereegranskat)abstract
- A method for studying protein orientation is described, in which the relative volumes of single proteins and single molecule complexes are measured using atomic force microscopy (AFM). Site-specific ligands are used as “probes” to bind to surface adsorbed proteins. The quantity of formed complexes gives an estimate of the amount of protein oriented in such a way as to allow ligand binding. The volume distribution for single proteins adsorbed to a surface was calculated and fitted to a Gaussian function. This volume distribution was used to localize the same proteins on surfaces with protein−ligand complexes, thus rendering it possible to find the amount of complex formed. Two model systems were used: one with two different mouse monoclonal antibodies of IgG1 type (mAb's against human serum transferrin, hST) adsorbed on silicon surfaces, and one with hST adsorbed to unmodified mica and aminated mica. The adsorbed proteins were allowed to react with a site-specific ligand, which binds to a defined region of the adsorbed protein (hST in the case of adsorbed mAb and lectin in the case of adsorbed hST). A great difference in ligand binding was found between the two antibodies adsorbed to the same type of surface as well as between hST adsorbed to different surfaces. This differance can be attributed to different orientation of the proteins on the surface. The general approach of this method suggests that it can be used for almost any site-specific molecule, either for surface orientation studies or studies where single molecule interactions need to be investigated.
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| 2. |
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| 4. |
- Bergkvist, Magnus, et al.
(författare)
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Surface-dependent conformations of human plasma fibronectin adsorbed to silica, mica, and hydrophobic surfaces, studied with use of Atomic Force Microscopy
- 2003
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Ingår i: Journal of biomedical materials research. Part A.. - : Wiley. - 0021-9304 .- 1097-4636. ; 64:2, s. 349-356
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Tidskriftsartikel (refereegranskat)abstract
- Human plasma fibronectin (Fn) is a large flexible protein stabilized by intermolecular ionic interactions forming a compact structure. On altering solution conditions, the structure can revert to a more expanded state, thereby exposing previously hidden domains (e.g., cell-binding sites). Electron microscopy images of Fn air-sprayed onto mica surfaces show elongated protein structures, indicating a surface-induced structural change. This makes it interesting to investigate the influence of surface properties on the structure of adsorbed Fn. We have used intermittent-contact Atomic Force Microscopy to investigate the structure of Fn adsorbed onto mica, silica, and methylated silica surfaces. We observed that on silica surfaces, which is hydrophilic, most (70%) of the molecules had an elongated structure with partial intramolecular chain interactions, compare to molecules adsorbed on hydrophobic, methylated surfaces, where a compact structure predominated (70%). On mica surfaces, both compact and elongated protein structures were observed, with a slight preference for the elongated form (53%). Results show that surface physical properties influence the molecular structure of fibronectin on adsorption, which could provide useful information in understanding surface-induced in vivo responses.
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| 5. |
- Bergkvist, Magnus, et al.
(författare)
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TM-AFM Threshold Analysis of Macromolecular Orientation : A Study of the Orientation of IgG and IgE on Mica Surfaces
- 1998
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Ingår i: Journal of Colloid and Interface Science. - : Elsevier BV. - 0021-9797 .- 1095-7103. ; 206:2, s. 475-481
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Tidskriftsartikel (refereegranskat)abstract
- Adsorption and orientation properties of two different types of immunoglobulin molecules on derivatized and native mica surfaces were investigated using TM-AFM. The analyses included height measurements at two different pH values and a new technique, presented here as threshold analysis, which displays the outer mantle shape of an adsorbed protein. A major difference in preferential orientation is observed upon comparing the adsorption of the two proteins onto the different surfaces. The characteristics of both the adsorbed immunoglobulin and the surface are important for any preferential orientation of the adsorbed protein.
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| 6. |
- Bergstedt Oscarsson, Kristina, et al.
(författare)
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Human Puumala hantavirus infection in northern Sweden : increased seroprevalence and association to risk and health factors
- 2016
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Ingår i: BMC Infectious Diseases. - : Springer Science and Business Media LLC. - 1471-2334. ; 16
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The rodent borne Puumala hantavirus (PUUV) causes haemorrhagic fever with renal syndrome in central and northern Europe. The number of cases has increased and northern Sweden has experienced large outbreaks in 1998 and 2006-2007 which raised questions regarding the level of immunity in the human population.METHODS: A randomly selected population aged between 25 and 74 years from northern Sweden were invited during 2009 to participate in a WHO project for monitoring of trends and determinants in cardiovascular disease. Health and risk factors were evaluated and sera from 1,600 participants were available for analysis for specific PUUV IgG antibodies using a recombinant PUUV nucleocapsid protein ELISA.RESULTS: The overall seroprevalence in the investigated population was 13.4 %, which is a 50 % increase compared to a similar study only two decades previously. The prevalence of PUUV IgG increased with age, and among 65-75 years it was 22 %. More men (15.3 %) than women (11.4 %) were seropositive (p < 0.05). The identified risk factors were smoking (OR = 1.67), living in rural areas (OR = 1.92), and owning farmland or forest (OR = 2.44). No associations were found between previous PUUV exposure and chronic lung disease, diabetes, hypertension, renal dysfunction, stroke or myocardial infarction.CONCLUSIONS: PUUV is a common infection in northern Sweden and there is a high life time risk to acquire PUUV infection in endemic areas. Certain risk factors as living in rural areas and smoking were identified. Groups with increased risk should be targeted for future vaccination when available, and should also be informed about appropriate protection from rodent secreta.
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| 7. |
- Deirmina, Faraz, et al.
(författare)
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Influence of boron on the stress-rupture behavior of an additively manufactured Hastelloy X
- 2023
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Ingår i: Materials Science & Engineering. - : Elsevier BV. - 0921-5093 .- 1873-4936. ; 863
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Tidskriftsartikel (refereegranskat)abstract
- The influence of minor additions of boron and the as-built (AB) microstructure on stress-rupture behavior of a modified crack-free Hastelloy X fabricated by laser powder bed fusion (L-PBF) was investigated. Isothermal stress rupture tests were performed at 816 degrees C under a static tensile load of 103 MPa. Micro-void formation in the vicinity of carbide precipitates and their coalescence was only observed at chevron-like high-angle grain boundaries, characteristic of L-PBF process. These grain boundaries, laying on the planes with maximum resolved shear stress with respect to the loading direction, directly governed the intergranular crack propagation. In view of the fracture mechanism and the time to rupture, increasing boron content significantly improves timeto-rupture through a diffusion-controlled mechanism by hindering the carbon diffusion to the grain boundaries. Adequate additions of boron (>10 ppm) guarantee the stress-rupture properties (strength) of the AB components without the need for additional post-thermal treatments. Further increase in boron content (i.e., 30 ppm), led to about five times increase in time to rupture (500 h vs. 110 h), and significantly improved creep elongation (30% vs. 9%) compared with the low boron alloy.
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| 8. |
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| 9. |
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| 11. |
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| 12. |
- Jidesjö, Anders, 1972-, et al.
(författare)
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Science and Technology Education for aDiverse World. Dilemmas, Needs and Partnerships
- 2004
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Ingår i: Science and Technology Education for aDiverse World. Dilemmas, Needs and Partnerships. - Lublin, Poland : Maria CurieSklodowska University Press. - 8322724977 ; , s. 295-307
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- This hook is a collection of 39 selected papers hy authors from various countries. All were participants in XI'h Symposium of the International Organization Science and Technology Education organized hy Maria Sklodowska University. Luhlin (Poland) from 25-30 July, 2(KM. Publication was in 2006. The papers present a great diversity of issues related to science and technology teaching in various countries, their role in the general education of pupils as well as their importance …
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| 13. |
- Jidesjö, Anders, et al.
(författare)
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Science for all or science for some: What Swedish students want to learn about in secondary science and technology and their opinions on science lessons
- 2009
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Ingår i: NorDiNa. - : UiO, University of Oslo. - 1504-4556 .- 1894-1257. ; 5:2, s. 213-229
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Tidskriftsartikel (refereegranskat)abstract
- This article presents Swedish results from ‘the Relevance of Science Education’ (ROSE) study, which is a large world wide comparative research project based at the University of Oslo. The Swedish sample consisted of 751 students, most of whom were 15 years old, from 29 schools and data were collected in spring 2003. Student opinions about science lessons are presented in relation to enrolment intentions for upper secondary school together with what they want to learn about in science and technology. The findings indicate that secondary science instruction seems to address only a minority of the students, those that have chosen science or technology in their further education. At the same time, all students have interest in science and technology and many seem most interested in some important issues in societal development. The results are discussed from the perspective of learners and contribute to the debate about establishing a scientific literacy approach in compulsory education.
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| 14. |
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| 15. |
- Jidesjö, Anders, et al.
(författare)
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Students´ attitudes to science. Some results from the ROSE-project in Sweden.
- 2004
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The ROSE-project tries to trap aspects of the interest in science education through a questionnaire about attitudes to science and technology among 15 year old students. The underlying idea is that the lack of relevance of the science and technology curriculum is one of the greatest barriers for good learning, and for interest in these subjects. There are about 40 countries taking part in ROSE and in Sweden we received data from 29 schools with a total sample of 751 students. Girls, just like the boys, show interest in space and life in other places of the universe. However, girls� most favourable items concerns health, fitness, dreams and occultism. Boys display a keen interest in cosmology, the function of technological advices and what can happen with the human body in different situations. Throughout, girls are more interested than boys and we interpret the result as an effect of the fact that girls are more successful in the read and write school that exists in Sweden today. Many of the items teachers traditionally teach in our science classes, like science fact, are found among items students do not want to learn. Instead students want to learn about things science cannot yet explain and do not have a clear opinion about. With the results from the ROSE project we find clear and distinct proofs that the science curriculum must bee renewed, if we want the rising generation to experience science and technology as being relevant.
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| 16. |
- Jidesjö, Anders, 1972-, et al.
(författare)
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Trends and developments in student’s interest in Science and technology: Results from the Relevance of science education second (ROSES) study in Sweden
- 2021
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Ingår i: Science education in the light of Global Sustainable Development: Trends and Possibilities.. - Aarhus, Denmark. - 9788799592043 ; , s. 148-156
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Konferensbidrag (refereegranskat)abstract
- This paper report Swedish results from a large-scale research project called “The Relevance of Science Education Second (ROSES)” which builds on a previous study called Relevance of Science education (ROSE). The studies are concerned with student’s interest in and attitudes towards science and technology (S&T) in and outside education from a student’s perspective. ROSES builds on collaboration between researchers in countries all around the world from a notion where education is apprehended as culturally embedded, and countries face different challenges but can also share some common. In this connection, research literature points out the importance of a science literate population together with the need of the recruitment of future expertise as educational goals for S&T. As many students have problems of perceiving the relevance of S&T in school there is an international concern and research interest to investigate trends and developments. In this paper preliminary Swedish results from ROSES are presented concerned with student’s experiences of S&T lessons and what they want to learn about. Data were collected in 2020. The results indicate that there are some changes in motion but at the same time student’s interest for critical content areas seem to be robust. The results are discussed and connected with the development of theoretical perspectives concerned with science identity, modernity and science capital. The reporting is framed in a Nordic perspective.
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| 17. |
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| 18. |
- Karlsson, Karl Göran, et al.
(författare)
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Fysik i ingenjörsutbildningen
- 2002
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Ingår i: Sju ämnesdidaktiska artiklar. - Härnösand : Institutionen för humaniora, Mitthögskolan. - 9163126680 ; , s. 33-50
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Den obligatoriska fempoängskursen i fysik som ingår i Mitthögskolans ingenjörsutbildningar uppfattas som svår. Vi har undersökt kursen som genomfördes våren 2001 i Härnösand och Sundsvall. Efter två tentamina är knappt hälften av studenterna godkända. Låg studiemotivation, som dessutom minskar under kursens gång, i kombination med begränsade arbetsinsatser tycks förklara en stor del av det dåliga resultatet. Den bristande motivationen kan förklaras av att studenterna inte uppfattar innehållet som nyttigt varken för de vidare studierna eller för sitt kommande yrkesliv.
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| 19. |
- Karlsson, K G, et al.
(författare)
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Lärande i arbetet : bilder från några skolutvecklingsprojekt
- 2003
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Bok (övrigt vetenskapligt/konstnärligt)abstract
- Åtta skolutvecklingsprojekt inom ramen för projektet "Lärande i arbetet" beskrivs och kommenteras. Små och stora skolor i Jämtland har genomfört detta EU-projekt och vi visar på skillnader och förutsättingar i genomförandet
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| 20. |
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| 21. |
- Kullerstedt, Margareta, et al.
(författare)
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Hur ser ungdomar på naturvetenskap? : Projektarbete. NOT-projektet.
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Vi presenterar en kartläggning av 13-åringars attityder till och erfarenheter av naturvetenskap och teknik. Det visar sig att ungdomarna prioriterar tid för familj och vänner samt ett intressant arbete. I skolan vill de lära sig om dinosaurier, vulkaner, åska och hur djur kommunicerar. Kunskaper som ljus-optik och hur tvättmedel fungerar kommer längst ner på popularitetslistan. Det tyder på att innehållet i NO-undervisningen bör förändras. Eleverna anger jämförelsevis få ämnen de vill lära sig mer om och det visar att skolan måste konkurrera om utrymmet i det moderna informationssamhället Flickorna visar större tilltro till forskning och vetenskap än pojkarna. De är mindre oroliga för att vetenskapen ska påverka vår miljö negativt eller skapa problem för samhället. Pojkarna tycker i högre grad än flickorna att vetenskap är intressant och spännande, men oroar i gengäld för dess skadeverkningar.
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| 22. |
- Ledung, Greger, et al.
(författare)
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A Novel Method for Preparation of Disulfides on Silicon
- 2001
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Ingår i: Langmuir. - : American Chemical Society (ACS). - 0743-7463 .- 1520-5827. ; 17:20, s. 6056-6058
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Tidskriftsartikel (refereegranskat)abstract
- This work describes an efficient novel method to incorporate reactive disulfide bonds onto a silica surface under mild reaction conditions. The reactive thiol groups introduced onto the silicon surface in the first reaction step will be oxidized but easily converted into highly reactive thiopyridyl groups, which can therefore easily be utilized for further organic synthesis involving thiol-containing molecules. This is done in a way that yields approximately a monolayer of reactant on the surface, thereby not adding to the roughness of the surface, of special importance, for instance, for single molecule interaction studies.
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| 23. |
- Oscarsson, Lars, et al.
(författare)
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Medborgarnas informella insatser
- 2022
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Ingår i: Engagemangets gestaltningar. - : Studentlitteratur AB. - 9789144143071 ; , s. 129-162
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Bokkapitel (övrigt vetenskapligt/konstnärligt)
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| 24. |
- Oscarsson, Mikael, et al.
(författare)
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Genotyping of human cytochrome P450 2A6 (CYP2A6), a nicotine C-oxidase
- 1998
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Ingår i: FEBS Letters. - 0014-5793 .- 1873-3468. ; 438:3, s. 201-205
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Tidskriftsartikel (refereegranskat)abstract
- Cytochrome P450 2A6 (CYP2A6) is a polymorphic enzyme responsible for the oxidation of certain precarcinogens and drugs and is the major nicotine C-oxidase. The role of CYP2A6 for nicotine elimination was emphasised recently by the finding that smokers carrying defective CYP2A6 alleles consumed fewer cigarettes [Pianezza et al. (1998) Nature 393, 750]. The method used for CYP2A6 genotyping has, however, been found to give erroneous results with respect to the coumarin hydroxylase phenotype, a probe reaction for the CYP2A6 enzyme. The present study describes an allele-specific PCR genotyping method that identifies the major defective CYP2A6 allele and accurately predicts the phenotype. An allele frequency of 1-3% was observed in Finnish, Spanish, and Swedish populations, much lower than described previously.
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| 25. |
- Oscarsson, Magnus, et al.
(författare)
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Health Care or Atom Bombs : Interest profiles in science among 15-year old students in Sweden
- 2011
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Ingår i: NorDiNa. - Oslo. - 1504-4556 .- 1894-1257. ; 7:2, s. 190-201
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Tidskriftsartikel (refereegranskat)abstract
- The ROSE survey explores which science topics 15-year-old students want to study. By carrying out a factor analysis on results from Sweden it was possible to describe ten interest profiles. The interest profile with the strongest connection to the students’ interest in school science consists of topics such as explosive chemicals, ABC weapons, electric shocks, atoms and molecules. Only a minority of the students has these interests, but it is this minority who appreciates school science and who chooses to study science at upper secondary school. The factor analysis also reveals large differences between genders and furthermore, that the students’ own interests govern their choice of study programme at upper secondary school.
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| 26. |
- Oscarsson, Magnus
(författare)
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Interest profiles in science among 15-year old students in Sweden. : IOSTE XII symposium
- 2006
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The ROSE questionnaire asks about what science topics 15-year old students want to learn. By making a factor analysis of results from Sweden, it was possible to derive 18 factors. The factor with strongest connection to student interested in school science is created by topics like explosive chemicals, ABC weapons, electric shocks, atoms and molecules. A minority of the students has these interests and they appreciate school science and tend to choose science for upper secondary level. The factor analysis also shows that the students own interests govern their choice for upper secondary school.
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| 27. |
- Oscarsson, Magnus, et al.
(författare)
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Science for all or science for some : What Swedish science students want to learn about in secondary science and technology and their opinions on science lessons.
- 2009
-
Ingår i: NorDiNa. - 1504-4556 .- 1894-1257. ; 5:2, s. 213-229
-
Tidskriftsartikel (refereegranskat)abstract
- This article presents Swedish results from ‘the Relevance of Science Education’ (ROSE) study, which is a large world wide comparative research project based at the University of Oslo. The Swedish sample consisted of 751 students, most of whom were 15 years old, from 29 schools and data were collected inspring 2003. Student opinions about science lessons are presented in relation to enrolment intentions for upper secondary school together with what they want to learn about in science and technology.The findings indicate that secondary science instruction seems to address only a minority of the students, those that have chosen science or technology in their further education. At the same time, all students have interest in science and technology and many seem most interested in some important issues in societal development. The results are discussed from the perspective of learners and contribute to the debate about establishing a scientific literacy approach in compulsory education.
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| 28. |
- Oscarsson, Magnus, et al.
(författare)
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Science in society or science in school : Swedish secondary teachers' beliefs about science and science lessons compared with what their students want to learn
- 2009
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Ingår i: NorDiNa. - 1504-4556 .- 1894-1257. ; 5:1, s. 18-34
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Tidskriftsartikel (refereegranskat)abstract
- Abstract This article presents comparisons concerned with secondary school science teachers’ and their students’beliefs about science and technology and also what science content secondary science teachersteach and what their students want to learn. Student data are part of the Relevance of Science Education(ROSE) study and the teacher data are part of an extensive study carried out only in Sweden. Theresults indicate that both secondary science teachers and their students are optimistic about scienceand technology as essential parts of societal development. When content from these knowledge fieldsis considered for instruction, significant disparities exist between what teachers teach and what theirstudents want to learn. Additional results concerning the secondary science teachers’ beliefs, ‘out-ofschoolexperiences’, ‘Science Technology and Society’ (STS) approaches and ‘inquiry-based instruction’are pointed out as important for the development of science instruction in secondary schools. Theresults are discussed in the contexts of students’ voices and teachers’ beliefs.
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| 29. |
- Oscarsson, Magnus, et al.
(författare)
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Science in society or science in school: Swedish secondary school science teachers' beliefs about science and science lessons in comparison with what their students want to learn
- 2009
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Ingår i: NorDiNa. - : UiO, University of Oslo. - 1504-4556 .- 1894-1257. ; 5:1, s. 18-34
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Tidskriftsartikel (refereegranskat)abstract
- This article presents comparisons concerned with secondary school science teachers’ and their students’ beliefs about science and technology and also what science content secondary science teachers teach and what their students want to learn. Student data are part of the Relevance of Science Education (ROSE) study and the teacher data are part of an extensive study carried out only in Sweden. The results indicate that both secondary science teachers and their students are optimistic about science and technology as essential parts of societal development. When content from these knowledge fields is considered for instruction, significant disparities exist between what teachers teach and what their students want to learn. Additional results concerning the secondary science teachers’ beliefs, ‘out-of-school experiences’, ‘Science Technology and Society’ (STS) approaches and ‘inquiry-based instruction’ are pointed out as important for the development of science instruction in secondary schools. The results are discussed in the contexts of students’ voices and teachers’ beliefs.
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| 30. |
- Oscarsson, Magnus, et al.
(författare)
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Science teachers´ instruction in relation to students´ interests and experiences Two divergent agendas : IOSTE XII symposium
- 2006
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Students´ attitudes to science and technology are measured with a questionnaire in an international research project called ROSE, the Relevance Of Science Education. This is done by asking questions about what 15-year-old students want to learn about, their experiences in and outside school and their opinions about science and technology. In another questionnaire, science teachers in Sweden were asked the same questions. Comparing these data shows that science in school is many times not in line with the young people of today. Trying to understand this situation can help in developing a science agenda in service of the learners.
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| 31. |
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| 32. |
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| 33. |
- Zetterlund, Eva-Lena, et al.
(författare)
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Determination of loss of consciousness: a comparison of clinical assessment, bispectral index and electroencephalogram: An observational study
- 2016
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Ingår i: European Journal of Anaesthesiology. - : Lippincott Williams & Wilkins. - 0265-0215 .- 1365-2346. ; 33:12, s. 922-928
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUNDComputer-processed algorithms of encephalographic signals are widely used to assess the depth of anaesthesia. However, data indicate that the bispectral index (BIS), a processed electroencephalography monitoring system, may not be reliable for assessing the depth of anaesthesia.OBJECTIVEThe aim of this study was to evaluate the ability of the BIS monitoring system to assess changes in the level of unconsciousness, specifically during the transition from consciousness to unconsciousness, in patients undergoing total intravenous anaesthesia with propofol. We compared BIS with the electroencephalogram (EEG), and clinical loss of consciousness (LOC) defined as loss of verbal commands and eyelash reflex.DESIGNThis was an observational cohort study.SETTINGUniversity Hospital Linkoping, University Hospital orebro, Finspang Hospital and Kalmar Hospital, Sweden from October 2011 to April 2013.PATIENTSA total of 35 ASA I patients aged 18 to 49 years were recruited.INTERVENTIONSThe patients underwent total intravenous anaesthesia with propofol and remifentanil for elective day-case surgery. Changes in clinical levels of consciousness were assessed by BIS and compared with assessment of stage 3 neurophysiological activity using the EEG. The plasma concentrations of propofol were measured at clinical LOC and 20 and 30min after LOC.MAIN OUTCOME MEASURESThe primary outcome was measurement of BIS, EEG and clinical LOC.RESULTSThe median BIS value at clinical LOC was 38 (IQR 30 to 43), and the BIS values varied greatly between patients. There was no correlation between BIS values and EEG stages at clinical LOC (r=-0.1, P=0.064). Propofol concentration reached a steady state within 20min.CONCLUSIONThere was no statistically significant correlation between BIS and EEG at clinical LOC. BIS monitoring may not be a reliable method for determining LOC.CLINICAL TRIALS REGISTRYThis trial was not registered because registration was not mandatory at the time of the trial.
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