| 1. |
- Adeyinka, A, et al.
(author)
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Cytogenetic heterogeneity and clonal evolution in synchronous bilateral breast carcinomas and their lymph node metastases from a male patient without any detectable BRCA2 germline mutation
- 2000
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In: Cancer Genetics and Cytogenetics. - 0165-4608. ; 118:1, s. 42-47
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Journal article (peer-reviewed)abstract
- Two synchronous bilateral breast carcinomas and their matched lymph node metastases from a 70-year-old man were cytogenetically analyzed. All four tumors were near-diploid, and except for the primary tumor from the right breast, had a 45,X,-Y clone in common. The loss of the Y chromosome was, however, common to all four tumors, whereas metaphase cells from peripheral blood lymphocytes showed a normal 46, XY chromosome complement. The primary tumor from the right breast was monoclonal, with loss of the Y chromosome and gain of 1q, whereas its metastasis had two related clones: the 45,X,-Y clone, and the other a more complex version of the clone in the primary tumor, with inv(3), -14, and del(16)(q13) as additional changes. The primary tumor from the left breast was polyclonal with three unrelated clones: 45,X,-Y/45,XY,-18/47,XY,+20, two of which were present in its metastasis. DNA flow cytometric studies showed diploidy for both primary tumors. No mutation in the BRCA2 gene was found on analysis of DNA from peripheral blood lymphocytes. The present findings show that del(16)(q13) is a recurrent finding among male breast carcinomas and that some of the primary cytogenetic abnormalities, as well as the pattern of chromosomal changes during the progression of sporadic breast carcinoma in the male, are similar to those in the female. In addition, the loss of the Y chromosome in the tumors but not in peripheral blood lymphocytes, suggests a possible role for this abnormality in the pathogenesis of male breast carcinoma.
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| 2. |
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| 3. |
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| 4. |
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| 5. |
- Andersson, Magnus, et al.
(author)
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DUAL PERSPECTIVES ON MULTI-CONTEXTUALITY OF DATA IN DIGITAL PLATFORM ESTABLISHMENT
- 2020
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In: Proc of 21st CINet Conference. - 9789077360231
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Conference paper (peer-reviewed)abstract
- Innovation in ecosystems becomes increasingly attractive for incumbents as the technical complexity increases and complementarities play an increasingly important role for global competition. Digital platforms are becoming one of the primary means to that end, where incumbents can gain scale effects and reap the benefits of the creative crowd while maintaining ownership of the core product. But a lion’s share of these platforms hinges on the accessibility of data, and the view of the value and ownership of this data differs among actors in the system. This paper accounts for a case study of two type actors in an innovation ecosystem; the keystone firm and the third-party service provider. From interviews with representatives of these actors, we formulate a tentative description of their perspective on the sharing of data in the ecosystem. We find that these perspectives differ in terms of data contextuality and customer value. We argue that these differing perspectives are at the crux of establishing innovation capabilities in ecosystems based on digital platforms.
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| 6. |
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| 7. |
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| 8. |
- Brytting, Tomas, 1956-, et al.
(author)
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Pinsamt, Svenskt Näringsliv
- 2007
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In: Svenska dagbladet. - Stockholm : Hb Svenska dagbladets AB & Co. - 1101-2412. ; :13 december
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Journal article (pop. science, debate, etc.)
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| 9. |
- Böttcher (Fagerås), Malin, et al.
(author)
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Endotoxin levels in Estonian and Swedish house dust and atopy in infancy
- 2003
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In: Clinical and Experimental Allergy. - : Wiley. - 1365-2222 .- 0954-7894. ; 33:3, s. 295-300
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Journal article (peer-reviewed)abstract
- Background Immune responses, including those to allergens, may be T helper (Th)2 skewed in newborns. In order to redress the fetal Th1/Th2 imbalance, Th1-stimulating factors, such as bacterial endotoxin, may be required. The increasing prevalence and severity of atopic diseases in industrialized countries, which are in marked contrast with the low prevalence of allergy among children in the formerly socialist countries of Europe, have been suggested to be caused by a reduced microbial stimulation.Aim To relate the endotoxin levels in house dust from two countries with a low (Estonia) and a high (Sweden) prevalence of allergy to the development of atopic disease and sensitization in the children during the first 2 years of life.Methods The study included 108 children from Tartu, Estonia and 111 children from Linköping, Sweden. Skin prick tests were performed at 3, 6, 12 and 24 months of age, and questionnaires were distributed to the families. At 24 months, a paediatrician examined the children. Dust samples were collected from mattresses and carpets and the endotoxin concentration was determined by a chromogenic Limulus assay.Results The endotoxin levels were higher in Estonian than in Swedish house dust (median levels 29 (range 0.25–280) and 14 (range 0.25–99) EU/mg dust, respectively, P < 0.001). Furthermore, the levels were inversely related to the development of atopic disease and sensitization in the Swedish, but not in the Estonian, children.Conclusions The low prevalence of atopic disease in Estonia may, at least in part, be related to the high endotoxin levels in this country. The findings support that high levels of endotoxin, or other bacterial products with Th1-stimulating properties, might protect children from developing atopic disease.
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| 10. |
- Böttcher, Johanna, et al.
(author)
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Adding a smartphone app to internet-based self-help for social anxiety : A randomized controlled trial
- 2018
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In: Computers in human behavior. - : Elsevier BV. - 0747-5632 .- 1873-7692. ; 87, s. 98-108
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Journal article (peer-reviewed)abstract
- Background: Increasing access to treatment via smartphone apps is an important topic in Social Anxiety Disorder (SAD). ‘Challenger’ is an app promoting exposure exercises in daily life. The present study evaluated the additional benefit of using the app as adjunct to Internet-based unguided self-help for SAD. In a second step, we also tested how the app and the self-help programme (SH) should best be combined.Method: 209 patients diagnosed with SAD were randomly allocated to three groups. Group 1 received the app and the self-help programme for six weeks (parallel treatment), group 2 first received SH for six weeks and then the app for six weeks (sequential treatment). Group 3 was a wait-list group. Comparisons were made at week 7 evaluating the potential add-on effect of the app (SH plus app versus SH only) and at week 14 comparing the parallel to the sequential treatment. Participants filled in questionnaires prior, during, and post treatment, and at 4- and 12- months follow-up.Results: Intention-to-treat analyses showed no significant effect of adding the app to Internet-based self-help. However, among participants actively using the app, adding Challenger to self-help resulted in significantly less social anxiety (d = 0.30). At week 14, decreases in social anxiety were large for both the parallel and the sequential group with no differences between the active groups (dwithin = 1.12–1.19). Changes were maintained throughout the follow-up period.Conclusion: Results of the current study cautiously support the notion of adding a smartphone app to unguided self-help for SAD. Future studies should investigate how patients can be motivated to use the app more frequently.
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| 11. |
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| 12. |
- Chen, Jianyong, et al.
(author)
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An Experimental Study of Vapor Ejectors Working with R245fa
- 2017
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In: Second Thermal and Fluids Engineering Conference. - 9781567004304 ; , s. 925-928
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Conference paper (peer-reviewed)abstract
- The vapor ejector is the key component in the ejector refrigeration system. The ejector determines the working stability and performance of the whole system. A specific test rig was designed and built with a focus on the performance of ejector itself. Instead of a circulation pump and a generator in the ejector refrigeration system, a compressor was used as the driving source. R245fa was selected as the working fluid. The important parameters, like pressure, temperature and mass flow rate, were measured and recorded. The entrainment ratio was obtained at a maximum value of 0.28. It was found that using ideal gas law and an appropriate value of the ejector nozzle isentropic efficiency could provide reasonable predictions of the mass flow rate through the ejector nozzle. Moreover, the insignificant impact of the superheat of the secondary flow on entrainment ratio was verified.
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| 13. |
- Cunha, Maria Lucelinda, et al.
(author)
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Possibilities to use oxidic by-products for precipitation of Fe/As from leaching solutions for subsequent base metal recovery
- 2008
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In: Minerals Engineering. - : Elsevier BV. - 0892-6875 .- 1872-9444. ; 21:1, s. 38-47
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Journal article (peer-reviewed)abstract
- In acidic biological and chemical leaching processes for base metal recovery, iron is dissolved in addition to the desired metal values. Prior to valuable metal extraction iron has to be removed. This is usually achieved through hydroxide precipitation of ferric iron by the addition of lime or limestone to a pH of approximately 3 whereby ferric hydroxide is formed. The aim of this work has been to investigate the possibility to substitute lime or limestone with oxidic industrial by-products for neutralisation and precipitation of iron from leaching solutions. The neutralisation potential for 10 selected oxidic by-products like slags, ashes and dusts were examined and compared with slaked lime.Experiments were performed by decreasing pH to 3 by additions of H2SO4 to slurry of respective by-product at an S/L ratio of 1/10 at 25 °C and continued till no changes in pH were observed during 10 days. Original samples, residues and solutions were analysed by ICP-MS and XRD in order to identify potential harmful elements for the subsequent metal recovery steps.Characterisation of the by-products revealed high concentrations of oxides such as lime, calcite and metal oxides as well as different forms of silicates in the materials which all dissolved at pH 3. The neutralising potential was found to be high for most of the by-products investigated and in the case of Ladle slag it was even higher than for slaked lime. Slags generally had higher neutralisation potential and long-term effects while the ashes had high initial reactivity which is important for continuous neutralisation in stirred tanks with limited retention times. The most reactive materials were Bioash and Mesa lime which both contained considerable amounts of calcite. Replacement of the conventional lime and limestone with oxidic by-products for neutralisation of acidic leaching solutions has the potential to save costs, environmental resources, reduce CO2 emissions and to recycle metal values like zinc contained in the by-products.
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| 14. |
- Cziáky, Z., et al.
(author)
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Synthesis of 2H‐pyrano[2,3‐b]quinolines. Part II. Preparation and 1H‐nmr investigations of 4‐hydroxy‐2‐methyl‐3,4‐dihydro‐2H‐pyrano[2,3‐b]quinolines
- 1995
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In: Journal of Heterocyclic Chemistry. - : Wiley. - 0022-152X .- 1943-5193. ; 32:3, s. 755-760
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Journal article (peer-reviewed)abstract
- Diastereoisomers of 4‐hydroxy‐2‐methyl‐3,4‐dihydro‐2H‐pyrano[2,3‐b]quinolines 8 and 9 were synthesized starting from the appropriate 2‐chloroquinoline‐3‐carboxaldehydes 1. The relative configuration of the 1,3‐diol intermediates 4 and 5 was determined on the basis of the 13C‐nmr spectra of their acetonides. The relative stereochemistry of title compounds was confirmed by using homonuclear NOE and selective decoupling experiments, as well as by analysis of the coupling patterns observed in their 1H‐nmr spectra.
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| 15. |
- Dimas, Antigone S, et al.
(author)
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Impact of type 2 diabetes susceptibility variants on quantitative glycemic traits reveals mechanistic heterogeneity.
- 2014
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In: Diabetes. - : American Diabetes Association. - 1939-327X .- 0012-1797. ; 63:6, s. 2158-2171
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Journal article (peer-reviewed)abstract
- Patients with established type 2 diabetes display both beta-cell dysfunction and insulin resistance. To define fundamental processes leading to the diabetic state, we examined the relationship between type 2 diabetes risk variants at 37 established susceptibility loci and indices of proinsulin processing, insulin secretion and insulin sensitivity. We included data from up to 58,614 non-diabetic subjects with basal measures, and 17,327 with dynamic measures. We employed additive genetic models with adjustment for sex, age and BMI, followed by fixed-effects inverse variance meta-analyses. Cluster analyses grouped risk loci into five major categories based on their relationship to these continuous glycemic phenotypes. The first cluster (PPARG, KLF14, IRS1, GCKR) was characterized by primary effects on insulin sensitivity. The second (MTNR1B, GCK) featured risk alleles associated with reduced insulin secretion and fasting hyperglycemia. ARAP1 constituted a third cluster characterized by defects in insulin processing. A fourth cluster (including TCF7L2, SLC30A8, HHEX/IDE, CDKAL1, CDKN2A/2B) was defined by loci influencing insulin processing and secretion without detectable change in fasting glucose. The final group contained twenty risk loci with no clear-cut associations to continuous glycemic traits. By assembling extensive data on continuous glycemic traits, we have exposed the diverse mechanisms whereby type 2 diabetes risk variants impact disease predisposition.
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| 16. |
- Dimassi, H, et al.
(author)
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Views of community pharmacists in Lebanon on the unified prescription: a mixed method study
- 2020
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In: Eastern Mediterranean health journal = La revue de sante de la Mediterranee orientale = al-Majallah al-sihhiyah li-sharq al-mutawassit. - : World Health Organization Regional Office for the Eastern Mediterranean (WHO/EMRO). - 1687-1634. ; 26:12, s. 1539-1547
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Journal article (peer-reviewed)abstract
- Background: The unified prescription was introduced in Lebanon in 2011; an aim was to save on medication expenditure. Aims: The aim of this study was to evaluate the views of community pharmacists on the effect and usefulness of the unified prescription. Methods: A cross-sectional telephone survey of community pharmacists from all governorates of Lebanon was conducted. A questionnaire was used to collect demographic data, pharmacists’ views on the effect of the unified prescription on their work, the percentage of prescriptions in which the prescriber had indicated that the medicine should not be substituted with a generic equivalent and the percentage needing clarification from the prescriber. Face-to-face interviews were held with 12 pharmacists to explore their views further. Results: Of 251 pharmacists interviewed, 56.8% did not think the unified prescription was useful, 34.8% thought it complicated their work and 24.0% that it reduced their autonomy. The in-depth interviews showed that autonomy was perceived to be restricted because of the difficulty in convincing patients to accept a substitute generic medicine, which the unified prescription allowed. The unified prescription complicated pharmacists’ work because of increased paperwork and the need for more storage. Pharmacists felt that the large number of prescriptions in which the prescriber had indicated that the medicine should not be substituted undermined the purpose of the unified prescription. Conclusion: The implementation of the unified prescription was not considered a success by community pharmacists in Lebanon. Efforts are needed to improve communication with prescribers and educate the public about pharmacists’ role and generic medicines.
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| 17. |
- Dimberg, Anna, 1971-
(author)
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The Role of Stat1 in Retinoic Acid-induced Myelomonocytic Differentiation of Human Leukemia Cells
- 2002
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Doctoral thesis (other academic/artistic)abstract
- All-trans retinoic acid (ATRA), a biologically active metabolite of vitamin A, is a powerful inducer of terminal differentiation and growth arrest of several myeloid cell lines in vitro. Although the efficacy of ATRA as an anti-cancer drug has been demonstrated by the successful treatment of acute promyelocytic leukemia (APL), knowledge concerning the molecular mechanisms directing ATRA-induced differentiation and cell cycle arrest of myeloid cells is lacking. Our results show, for the first time, that the complex regulation of cell cycle proteins and myeloid-specific transcription factors induced by ATRA relies on functional Stat1. We found that Stat1 is activated by both tyrosine-701 and serine-727 phosphorylation upon ATRA-induced differentiation of the human monoblastic cell line U-937. Expression of phosphorylation deficient mutants of Stat1 (Stat1Y701F or Stat1S727A) inhibited both ATRA-induced differentiation and cell cycle arrest of U-937 cells, pointing to a requirement of active Stat1 in these processes. Detailed analysis of the molecular mechanism of ATRA-induced cell cycle arrest and differentiation showed that the onset of cell cycle arrest was associated with a decrease in c-Myc and cyclin E levels and upregulation of p27Kip1 and p21WAF1/CIP1. This was followed by a rapid fall in cyclin A and B and a coordinate dephosphorylation of the retinoblastoma protein (pRb). The inhibition of ATRA-induced cell-cycle arrest by constitutive expression of Stat1Y701F or Stat1S727A was associated with impaired regulation of these cyclins and p27Kip1, positioning Stat1 activation upstream of these events. To further understand the process of ATRA-induced differentiation, the regulation of myeloid-specific transcription factors was investigated during ATRA-treatment. Notably, ATRA-induced upregulation of Stat2, ICSBP and C/EBP-ε was selectively impaired in sublines expressing Stat1Y701F or Stat1S727A, suggesting an important function of these factors downstream Stat1. Taken together, the work in this thesis clearly demonstrates that Stat1 plays a key role in ATRA-induced terminal differentiation of myeloid cells, through regulation of cell cycle proteins and myeloid-specific transcription factors.
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| 18. |
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| 19. |
- Du, Hao, et al.
(author)
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Bipolar HiPIMS : The role of capacitive coupling in achieving ion bombardment during growth of dielectric thin films
- 2021
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In: Surface & Coatings Technology. - : Elsevier BV. - 0257-8972 .- 1879-3347. ; 416
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Journal article (peer-reviewed)abstract
- Bipolar high-power impulse magnetron sputtering (HiPIMS) is used to achieve ion acceleration for ion bombardment of dielectric thin films. This is realized by increasing the plasma potential (U-p), during the interval in-between the HiPIMS-pulses, using a positive reversed voltage (U-rev). As long as the film surface potential (U-s) is maintained low, close to ground potential, this increase in U-p results in ion-acceleration as ions approach the film surface. The effect of U-rev on the ion bombardment is demonstrated by the growth of dielectric (Al,Cr)(2)O-3 films on two sets of substrates, Si (001) and sapphire (0001) utilizing a U-rev ranging from 0 to 300 V. A clear ion bombardment effect is detected in films grown on the conductive Si substrate, while no, or a very small, effect is observed in films grown on the dielectric sapphire substrate. This is ascribed to the changes in U-s when the substrate is subjected to the bombardment of positive ions. For a film surface that has a high capacitance to ground, U-s remains close to ground potential for an extended time in-between the HiPIMS pulses, while if the capacitance is low, U-s quickly attains floating potential (U-float) close to U-p. The simulated temporal evolutions of U-s for the films by using capacitors show that for a 1 mu m thick (Al,Cr)(2)O-3 film on a conductive substrate, U-s is maintained close to ground potential during the entire 20 mu s that U-rev is applied after the HiPIMS pulse. On the other hand, when a capacitance corresponding to the 0.5 mm thick sapphire substrate is used, U-s rapidly attains a potential close to U-rev.
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| 20. |
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| 21. |
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| 22. |
- Elshafie, Amir, 1970-, et al.
(author)
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General false positive ELISA reactions in visceral leishmaniasis. Implications for the use of enzyme immunoassay analyses in tropical Africa.
- 2016
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In: JIM - Journal of Immunological Methods. - : Elsevier BV. - 0022-1759 .- 1872-7905. ; 431, s. 66-71
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Journal article (peer-reviewed)abstract
- Leishmaniasis is a neglected disease in tropical countries. Clinical and laboratory features may mimic auto immune diseases and this can complicate the Leishmania diagnosis. Due to our previous investigation for false anti-CCP2 reactivity in Leishmania-infected subjects and our interest in immunity against the joint-specific collagen type II (CII) in rheumatoid arthritis (RA) we investigated the same cohort for anti-CII antibodies. We found elevated anti-CII reactivity in Leishmania-infected patients as compared to controls. When anti-CII OD values were compared with BSA-blocked control plates we found higher reactivity against BSA than in CII-coated plates in many Leishmania-infected patients. The percentage of such false positive anti-CII reactions increased with inflammatory activity, and was found in almost all Leishmania patients with highly active inflammatory disease, but was as low in Sudanese healthy controls as well as among Swedish RA patients. The correlation coefficients between false positive anti-CII and anti-CCP2 measured with a commercial ELISA were highest for patients with the most inflammatory disease but non-significant for Sudanese controls and Swedish RA patients, arguing that our findings may have general implications for ELISA measurements in leishmaniasis. ELISA investigations in areas endemic for leishmaniasis might benefit from individual-specific control wells for each serum sample. This approach might also be applicable to other geographical areas or patient groups with high incidence of inflammatory and infectious diseases.
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| 23. |
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| 24. |
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| 25. |
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| 26. |
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| 27. |
- Gabrielsson, Alf, 1936-
(author)
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Musikpsykologi : En introduktion
- 2020
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Book (other academic/artistic)abstract
- Musikpsykologi är läran om upplevelser coh beteenden i samband med musik. I denna bok ges en översikt över olika forskningsområden inom musikpsykologi med tyngdpunkt på hur musik kan uppfattas, upplevas, utföras och komponeras.
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| 28. |
- Gray, JS, et al.
(author)
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Lyme borreliosis awareness
- 1998
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In: Zentralblatt fur Bakteriologie : international journal of medical microbiology. - : Elsevier BV. - 0934-8840. ; 287:3, s. 253-265
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Journal article (peer-reviewed)
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| 29. |
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| 30. |
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| 31. |
- Grundström, Karin
(author)
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Room for Resistance - gendered appropiations of space in a poor urban community in Costa Rica
- 2009
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In: Meeting global challenges in research cooperation Proceedings of a conference and workshop in Uppsala, May 27–29, 2008. - 9789197574198 ; , s. 518-526
-
Conference paper (peer-reviewed)abstract
- This paper discusses spatial interventions as an important part of women’s struggles to improve their living conditions in poor urban areas. A case-study from San José, Costa Rica is the basis for the discussion. Women’s interventions are analyzed in three public places— a park, a playground and a community centre— through the concept of appropriation. The study shows that women’s interventions have influenced both the built environment and the position of the participating women. The study points out women’s participation and challenges the image of the female poor as passive victims.
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| 32. |
- Grundström, Karin
(author)
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Shared Housing as Public Space? The Ambiguous Borders of Social Infrastructure
- 2022
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In: Urban Planning. - : Cogitatio Press. - 2183-7635. ; 7:4
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Journal article (peer-reviewed)abstract
- The Folkhem era in Sweden set high architectural standards for social infrastructures dispersedly located in cities. Over the past two decades, however, Swedish planning, when it comes to the localization of social infrastructure, has been increasingly characterized by privatized social infrastructures added to housing. Methodologically, this article draws on a compilation of architectural designs of shared housing that includes social infrastructure, 12 interviews with developers, and 22 interviews with residents. The article argues, first, that two historical approaches can be identified: one in which porous borders support urban social life in and around the housing complex and another where distinct boundaries form an edge where things end. Secondly, the article argues that in recent shared housing complexes, the infrastructures of fitness, health care, and privatized services—previously available solely in the public realm—have moved physically and mentally closer to the individual, largely replacing residents’ everyday use of public space. The article concludes that in recent shared housing complexes, ambiguous borders are formed. Ambiguous borders allow a flow of goods and people, but the flow is based on the needs and preferences of residents only. Overall, such privatization counteracts the development of urban social life while adding to housing inequality, as this form of housing is primarily accessible only to the relatively wealthy. Furthermore, there is a risk that urban planning may favour such privatization to avoid maintenance costs, even though the aim of planning for general public accessibility to social infrastructure is thereby shifted towards planning primarily for specific groups.
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| 33. |
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| 34. |
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| 35. |
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| 36. |
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| 37. |
- Hardell, Jens, et al.
(author)
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Friction and wear behaviour of high strength boron steel at elevated temperatures of up to 800 °C
- 2008
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In: Wear. - : Elsevier BV. - 0043-1648 .- 1873-2577. ; 264:9/10, s. 788-799
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Journal article (peer-reviewed)abstract
- There has been a growing usage of high strength steels, particularly in automobile applications mainly as structural parts in view of their light weight and high strength properties. These materials are also being considered for dynamic applications. However, the understanding of their tribological behaviour vis-a-vis their hot forming and also as tribological materials is highly inadequate. The present work thus aims at creating new knowledge about the tribological characteristics of high strength steels and bridging this existing gap. High temperature tribological studies on different tool steels (with and without surface treatment) sliding against high strength boron steel (with and without coating) and studies on self-mated hardened high strength boron steel under dry reciprocating sliding conditions have been conducted. High temperature tribological studies keeping in view the hot metal forming aspects were conducted by using an SRV machine whereas a two-disc machine was employed for investigating their fundamental friction and wear behaviour. The results from the high temperature studies indicate that the friction is dependent on temperature since a reduced friction level was observed with increasing temperature. The wear of the tool steels increased with increasing temperature and nitriding of the tool steels provided better protection against severe wear. The results from the study on self-mated hardened high strength boron steel showed that sliding speed has a marginal effect on friction whereas the effect of contact pressure is more pronounced (decreasing friction with increased contact pressure). The specific wear rate decreased with increased sliding speed.
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| 38. |
- Hauryliuk, Vasili, 1980-
(author)
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A Few Strokes to the Family Portrait of Translational GTPases
- 2008
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Doctoral thesis (other academic/artistic)abstract
- Protein biosynthesis is a core process in all living organisms. Assembly of the protein chain from aminoacids is catalysed by the ribosome, ancient and extremely complex macromolecular machine. Several different classes of accessory molecules are involved in translation, and one set of them, called translational GTPases (trGTPases), was in the focus of this work. In this thesis properties of two trGTPases– EF-G and eRF3 - were studied by means of direct biochemical experiments. EF-G is a bacterial trGTPase involved in two steps of translation: translocation and ribosomal recycling. Translocation is a process of the ribosomal movement along the mRNA, and recycling as the step when upon completion of the protein ribosome is released from the mRNA via splitting in two ribosomal subunits. We found that off the ribosome EF-G has similar affinities to GDP and GTP, and thus given the predominance of the latter in the cell, EF-G should be present mostly in the complex with GTP. However, binding to the ribosome increases factors affinity to GTP drastically, ensuring that it is in the GTP-bound state. GDP can not promote neither translocation, not recycling, and GDPNP can not promote recycling. It can, however, promote translocation, but in so doing it results in an intermediate ribosomal state and translocation process can be reversed by addition of GDP, which is not the case for the EF-G•GTP-catalyzed reaction.The second trGTPase we investigated is eukaryotic termination factor eRF3. This protein together with another factor, eRF1, is involved translation termination, which is release of the synthesized protein from the ribosome. We demonstrateed, that eRF3 alone has basically no propensity to bind GTP and thus resides in the GDP-bound state. Complex formation between eRF1 and eRF3 promotes GTP binding by the latter, resulting in the formation of the ternary complex eRF1•eRF3•GTP, which in turn is catalyzing the termination event.Experimental investigations of trGTPases where rationalized within a generalized thermodynamical framework, accommoding the existent experimental observations, both structural and biochemical.
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| 39. |
- Hauryliuk, Vasili, et al.
(author)
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Class-1 release factor eRF1 promotes GTP binding by class-2 release factor eRF3
- 2006
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In: Biochimie. - : Elsevier BV. - 0300-9084 .- 1638-6183. ; 88:7, s. 747-757
-
Journal article (peer-reviewed)abstract
- In eukaryotes, termination of mRNA translation is triggered by the essential polypeptide chain release factors eRF1, recognizing all three stop codons, and eRF3, a member of the GTPase superfamily with a role that has remained opaque. We have studied the kinetic and thermodynamic parameters of the interactions between eRF3 and GTP, GDP and the non-hydrolysable GTP analogue GDPNP in the presence (K-D(GDP) = 1.3 +/- 0.2 mu M, K-D(GTP) approximate to 200 mu M and K-D(GDPNP) > 160 mu M) as well as absence (K-D(GDP) = 1.9 +/- 0.3 mu M, K-D(GTP) 0.7 +/- 0.2 mu M and K-D(GDPNP) approximate to 200 mu M) of eRF1. From the present data we propose that (i) free eRF3 has a strong preference to bind GDP compared to GTP (ii) eRF3 in complex with eRF1 has much stronger affinity to GTP than free eRF3 (iii) eRF3 in complex with PABP has weak affinity to GTP (iv) eRF3 in complex with eRF1 does not have strong affinity to GDPNP, implying that GDPNP is a poor analogue of GTP for eRF3 binding.
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| 40. |
- Hauryliuk, Vasili, et al.
(author)
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The pretranslocation ribosome is targeted by GTP-bound EF-G in partially activated form.
- 2008
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In: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 105:41, s. 15678-83
-
Journal article (peer-reviewed)abstract
- Translocation of the tRNA x mRNA complex through the bacterial ribosome is driven by the multidomain guanosine triphosphatase elongation factor G (EF-G). We have used isothermal titration calorimetry to characterize the binding of GDP and GTP to free EF-G at 4 degrees C, 20 degrees C, and 37 degrees C. The binding affinity of EF-G is higher to GDP than to GTP at 4 degrees C, but lower at 37 degrees C. The binding enthalpy and entropy change little with temperature in the case of GDP binding but change greatly in the case of GTP binding. These observations are compatible with a large decrease in the solvent-accessible hydrophobic surface area of EF-G on GTP, but not GDP, binding. The explanation we propose is the locking of the switch 1 and switch 2 peptide loops in the G domain of EF-G to the gamma-phosphate of GTP. From these data, in conjunction with previously reported structural data on guanine nucleotide-bound EF-G, we suggest that EF-G enters the pretranslocation ribosome as an "activity chimera," with the G domain activated by the presence of GTP but the overall factor conformation in the inactive form typical of a GDP-bound multidomain guanosine triphosphatase. We propose that the active overall conformation of EF-G is attained only in complex with the ribosome in its "ratcheted state," with hybrid tRNA binding sites.
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| 41. |
- Hellman, Olle, et al.
(author)
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Phonon thermal transport in Bi2Te3 from first principles
- 2014
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In: Physical Review B. Condensed Matter and Materials Physics. - : American Physical Society. - 1098-0121 .- 1550-235X. ; 90:13, s. 134309-
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Journal article (peer-reviewed)abstract
- We present first-principles calculations of the thermal and thermal transport properties of Bi2Te3 that combine an ab initio molecular dynamics (AIMD) approach to calculate interatomic force constants (IFCs) along with a full iterative solution of the Peierls-Boltzmann transport equation for phonons. The newly developed AIMD approach allows determination of harmonic and anharmonic interatomic forces at each temperature, which is particularly appropriate for highly anharmonic materials such as Bi2Te3. The calculated phonon dispersions, heat capacity, and thermal expansion coefficient are found to be in good agreement with measured data. The lattice thermal conductivity, kappa(l), calculated using the AIMD approach nicely matches measured values, showing better agreement than the kappa(l) obtained using temperature-independent IFCs. A significant contribution to kappa(l) from optic phonon modes is found. Already at room temperature, the phonon line shapes show a notable broadening and onset of satellite peaks reflecting the underlying strong anharmonicity.
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| 42. |
- Hildén, Ebba, 1976-
(author)
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Preschool teachers achieving agency
- 2018
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Conference paper (peer-reviewed)abstract
- Teaching is a concept that many in Sweden associate with what teachers do in schools, but not with what preschool teachers do in preschool. Many consider teaching to be something that the teacher does in front of a class of pupils in a formal setting where the teachers provide pupils with instructions in various lessons covering one subject at a time, according to agreed curricula.The Education Act and the curriculum regulate the Swedish preschool. According to the Education Act teaching is described as goal-oriented processes which enhances children’s development and learning and the concept is to be used in compulsory schools as well as in the preschools. The concept of teaching in preschools was included in the Educational Act in 2010, but is not mentioned in the preschool curriculum. Although preschool teachers are supposed to teach, inspections made by the Swedish Schools Inspectorate show that many do not. Many preschool teachers do not use the concept of teaching when describing what they do when promoting children´s learning and development. Instead, many talk of children´s learning. The Swedish preschool have a long tradition of positioning their pedagogical practice as something other than the pedagogical practice in compulsory schools and teaching being something that is thought of as something that is done only in schools make introducing the concept of teaching in preschool difficult. In order to get the preschool teachers to use the concept of teaching preschool principals try to focus on the concept of teaching in discussions amongst the staff.The aim of this paper is to discuss teacher agency and how it is achieved in concrete settings by preschool teachers and other staff. Data from an ongoing project is presented. The research questions areTo what extend is teacher agency achieved by preschool teachers when the concept of teaching is discussed?What structures frame the ability to achieve teacher agency?The empirical material consist of video recordings of actual events in the everyday practice in preschool and sound recordings of discussions between preschool teachers and other staff. The research method of video stimulated recall was used in order to obtain the preschool teacher´s thoughts and reflections on their own teaching. The empirical material was analyzed with the help of Biesta, Priestly and Robinson´s (2015) ecological model of teacher agency as a “temporally constructed engagement with different structural environments” (Emirbayer & Mische, p. 970, 1998). This model is informed by John Dewey´s pragmatic philosophy and his use of transactions. Preliminary findings show the importance of professionalism for preschool teacher in forming a structure that frames the ability to achieve teacher agency.References:Biesta, G., Priestley, M. & Robinson, S. (2015). The role of beliefs in teacher agency. Teachers and Teaching: theory and practice, 21 (6), 624-640.Emirbayer, M., & Mische, A. (1998). What is agency? American Journal of Sociology, 103, 962-1023.
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| 43. |
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| 44. |
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| 45. |
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| 46. |
- Khan, Umar, et al.
(author)
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Low power actuators for programmable photonic processors
- 2023
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In: AI and Optical Data Sciences IV. - : SPIE-Intl Soc Optical Eng.
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Conference paper (peer-reviewed)abstract
- The demand for efficient actuators in photonics has peaked with increasing popularity for large-scale general-purpose programmable photonics circuits. We present our work to enhance an established silicon photonics platform with low-power micro-electromechanical (MEMS) and liquid crystal (LC) actuators to enable large-scale programmable photonic integrated circuits (PICs).
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| 47. |
- Khoshnood, Ardavan, et al.
(author)
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Diagnostic accuracy of troponin T measured ≥6h after symptom onset for ruling out myocardial infarction
- 2020
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In: Scandinavian cardiovascular journal : SCJ. - : Informa UK Limited. - 1651-2006 .- 1401-7431. ; 54:3, s. 153-161
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Journal article (peer-reviewed)abstract
- Objectives: Guidelines recommend a single high-sensitivity cardiac troponin T (hs-cTnT) ≤14 ng/L measured ≥6 h after chest pain onset combined with a GRACE score <140 and the patient being pain-free for ruling out myocardial infarction (MI). There is however little data on the performance of this strategy. We therefore aimed to evaluate the diagnostic accuracy of a hs-cTnT ≤14 ng/L measured ≥6 h after chest pain onset when combined with GRACE score or other clinical risk stratification tools. Design: This was a secondary analysis of a prospective observational study, which enrolled emergency department (ED) chest pain patients. The hs-cTnT strategy was combined with HEART, TIMI, EDACS, GRACE score and ED physician's overall assessment of patient history and ECG. The primary outcome was MI, and the secondary outcome was 30-day major adverse cardiac events (MACE). Results: All tested diagnostic strategies were shown to have a negative predictive value (NPV) ≥99.5% for ruling out MI. Using HEART, TIMI, EDACS or ECG + patient history also resulted in a NPV ≥98% for ruling out 30-day MACE. An isolated hs-cTnT ≤14 ng/L measured ≥6 h after chest pain onset and the combination with GRACE score both had a NPV <98% for ruling out 30-day MACE. Conclusion: A single hs-cTnT ≤14 ng/L obtained ≥6 h from chest pain onset, with and without GRACE score, reliably ruled out MI but did not perform well for ruling out 30-day MACE. These results question current guideline recommendations, and indicate that HEART, EDACS, TIMI, or ECG + patient history strategies should be the preferred risk stratification tools.
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| 48. |
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| 49. |
- Li, B., et al.
(author)
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The Euclidean Distance Spectra of FDMA-CPM: Algorithms and Applications
- 2014
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In: Chinese Journal of Electronics. - 2075-5597 .- 1022-4653. ; 23:4, s. 821-826
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Journal article (peer-reviewed)abstract
- The performance of multiuser Continuous phase modulation(CPM) over the additive white Gaussian noise channel with coherent maximum likelihood detection is considered. Algorithms are developed to calculate the Euclidean distance spectra employing tree-search and A-star algorithm. The complexity of proposed algorithms are further reduced using trellis minimization. The distance spectrum is then used to evaluate the performance of multiuser CPM systems, which reveals that the performance of multiuser CPM can be significantly improved by using optimized parameters. Both equally-powered and non-equally powered systems are considered. Numerical and simulated results confirm that the proposed algorithms can generate the distance spectra of all systems with lower complexity relative to previous methods and are particularly suited for multi user CPM systems.
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| 50. |
- Li, Fusheng, 1985-, et al.
(author)
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Electroless Plating of NiFeP Alloy on the Surface of Silicon Photoanode for Efficient Photoelectrochemical Water Oxidation
- 2020
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In: ACS Applied Materials and Interfaces. - : American Chemical Society (ACS). - 1944-8244 .- 1944-8252. ; 12:10, s. 11479-11488
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Journal article (peer-reviewed)abstract
- N- type silicon is a kind of semiconductor with a narrow band gap that has been reported as an outstanding light-harvesting material for photoelectrochemical (PEC) reactions. Decorating a thin catalyst layer on the n-type silicon surface can provide a direct and effective route toward PEC water oxidation. However, most of catalyst immobilization methods for reported n-type silicon photoanodes have been based on energetically demanding, time-consuming, and high-cost processes. Herein, a high-performance NiFeP alloy (NiFeP)-decorated n-type micro-pyramid silicon array (n-Si) photoanode (NiFeP/n-Si) was prepared by a fast and low-cost electroless deposition method for light-driven water oxidation reaction. The saturated photocurrent density of NiFeP/n-Si can reach up to similar to 40 mA cm(-2) and a photocurrent density of 15.5 mA cm(-2) can be achieved at 1.23 V-RHE under light illumination (100 mW cm(-2), AM1.5 filter), which is one of the most promising silicon-based photoanodes to date. The kinetic studies showed that the NiFeP on the silicon photoanodes could significantly decrease the interfacial charge recombination between the n-type silicon surface and electrolyte.
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