| 1. |
- Grishin, Michael A., et al.
(författare)
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Electron structure and electron dynamics at InSb(111)2×2 semiconductor surface
- 2003
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Ingår i: Applied Physics A. - : Springer Science and Business Media LLC. - 0947-8396 .- 1432-0630. ; 76:3, s. 299-302
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Tidskriftsartikel (refereegranskat)abstract
- The conduction band electronic structure and the electron dynamics of the clean InSb(111)2 x 2 surface have been studied by laser based pump-and-probe photoemission. The results are compared to earlier studies of the InSb(110) surface. It is found that both the energy location and the time dependence of the photoexcited structures are very similar for the two surfaces. This indicates that the dominant part of the photoemission signal in the conduction band region is due to excitations of electrons in the bulk region and that the surface electronic states play a minor role. The fast decay of the excited state, tau similar to 12 ps, indicates that diffusion of hot electrons into the bulk is an important mechanism.
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| 2. |
- Karlsson, Klas-Göran, et al.
(författare)
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Historia och samhällsorientering - en ansträngd relation
- 2004
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Ingår i: Historen är nu. En introduktion till historiedidaktiken. - 9144034172 ; , s. 301-315
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Artikeln analyserar förhållandet mellan historia och samhällsorientering som skolämnen.
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| 3. |
- Karlsson, Klas-Göran, et al.
(författare)
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Historiedidaktik: begrepp, teori och analys
- 2004
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Ingår i: Historien är nu. En introduktion till historiedidaktiken. - 9144034172 ; , s. 13-66
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Artikeln är en genomgång av den historiedidaktiska forskningens teoretiska och begreppsliga redskap.
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| 4. |
- Karlsson, Klas-Göran, et al.
(författare)
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Historiedidaktik och historievetenskap - ett förhållande i utveckling
- 2004
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Ingår i: Historien är nu. En introduktion till historiedidaktiken. - 9144034172 ; , s. 185-202
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- Artikeln analyserar hur historiedidaktiska frågeställningar och begrepp fått ett allt starkare genomslag i den moderna historievetenskapen.
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| 5. |
- Karlsson, Klas-Göran, et al.
(författare)
-
Making Sense of the Holocaust after Sixty Years. An Introduction
- 2004
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Ingår i: Holocaust Heritage. Inquiries into European Historical Cultures. - 919752221X ; , s. 9-33
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The article is an introductory text of a conference volume, dedicated to the role of the Holocaust in post-War European historical discourse.
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| 6. |
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| 7. |
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| 8. |
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| 9. |
- Zander, Ulf, et al.
(författare)
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Holocaust at the Limits. Historical Culture and the Nazi Genocide in the Television Era
- 2003
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Ingår i: Echoes of the Holocaust. Historical Cultures in Contemporary Europe. - 9189116526 ; , s. 255-292
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The television series Holocaust: The Story of the Family Weiss (1978) had an enormous impact in USA and Western Europe. As a result of the broadcasting, a growing interest for the Holocaust became visible and caused a number of debates. In this article, I discuss the debates in USA, West Germany, Denmark and Sweden.
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| 10. |
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| 11. |
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| 12. |
- Abreu, P, et al.
(författare)
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b-tagging in DELPHI at LEP
- 2004
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Ingår i: European Physical Journal C. Particles and Fields. - : Springer Science and Business Media LLC. - 1434-6044. ; 32:2, s. 185-208
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Tidskriftsartikel (refereegranskat)abstract
- The standard method used for tagging b-hadrons in the DELPHI experiment at the CERN LEP Collider is discussed in detail. The main ingredient of b-tagging is the impact parameters of tracks, which relies mostly on the vertex detector. Additional information, such as the mass of particles associated to a secondary vertex, significantly improves the selection efficiency and the background suppression. The paper describes various discriminating variables used for the tagging and the procedure of their combination. In addition, applications of b-tagging to some physics analyses, which depend crucially on the performance and reliability of b-tagging, are described briefly.
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| 13. |
- Ahlström, Gerd, et al.
(författare)
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Disability and quality of life in individuals with postpolio syndrome.
- 2000
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Ingår i: Disability and Rehabilitation. - 0963-8288 .- 1464-5165. ; 22:9, s. 416-422
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: The purpose of the study is to investigate disability and quality of life in individuals with the characteristic symptoms of postpolio syndrome. METHOD: Disability is assessed by means of the self-report activities of daily living instrument, and quality of life by means of Kaasa's questionnaire and the quality of life profile. RESULTS: The 39 subjects have on average lived with polio sequelae for 52 years. Their main difficulties are with moving, lifting and carrying. This means restricted mobility, sedentary activities and a need to prioritize. Half of them feel that polio has lessened their possibilities in life, and a quarter have still not accepted the limitations polio has involved. Nevertheless the majority report a high level of psychosocial well-being, and almost a quarter say that living with polio has meant personal development and strength. We found a significant correlation between on the one hand disability with regard to ambulation, arm strength and finger strength on the self-report ADL, and on the other hand the number of negative problems on the quality of life profile (0.33-0.45). CONCLUSION: The latter instrument needs further testing before its validity can be determined with certainty.
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| 14. |
- Astrand, Per, et al.
(författare)
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A three-year follow-up report of a comparative study of ITI Dental Implants and Bråemark System implants in the treatment of the partially edentulous maxilla.
- 2004
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Ingår i: Clin Implant Dent Relat Res. - 1523-0899. ; 6:3, s. 130-41
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Many longitudinal studies of different implant systems have been published but few controlled randomized investigations have been reported. A 1-year report of a comparative study of ITI Dental Implant System implants (Straumann AG, Waldenburg, Switzerland) and Branemark System implants (Nobel Biocare AB, Gothenburg, Sweden) has been published by the present authors. This paper is a 3-year follow-up of that randomized study. PURPOSE: The aim of the study was to compare the outcome of fixed partial prostheses supported by ITI or Branemark implants. The outcome was evaluated primarily in terms of survival rates and changes in marginal bone level. MATERIAL AND METHODS: The study group comprised 28 patients with anterior residual dentition in the maxilla. The patients were provided with two to four implants on each side of the dentition and were randomly allocated to Branemark implants or ITI implants; 77 ITI implants and 73 Branemark implants were inserted. After 6 months abutment connections were made to both ITI and Branemark implants. All patients were provided with fixed partial prostheses of gold-ceramic. The patients were followed up annually with clinical and radiographic examinations for 3 years RESULTS: Two Branemark implants and two ITI implants were lost. The Branemark implants were lost before loading whereas the ITI implants were lost because of periimplantitis. The survival rate for both groups was 97.3%. The mean marginal bone level of the Branemark implants was situated 1.8 mm from the reference point at both the baseline and the 3-year examinations. The corresponding values for the ITI implants were 1.4 mm at baseline and 1.3 mm after 3 years. There was no significant difference between the implant systems with regard to bone level or bone level change. A steady state of the marginal bone level was calculated to have been reached after 3 years for 95.5% of the Branemark implants and 87.1% of the ITI implants. Periimplantitis (infection including pus and bone loss) was observed with seven ITI implants but with none of the Branemark implants. This difference was statistically significant. CONCLUSIONS: No statistically significant differences were found between the implants studied, except for the frequency of periimplantitis, which was higher for the ITI implants. The survival rates were high, and the marginal bone loss was small for both systems.
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| 15. |
- Berglund, Kristina, 1969, et al.
(författare)
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Changes in mental well-being during Minnesota treatment.
- 2004
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Ingår i: Nordic journal of psychiatry. - : Informa UK Limited. - 0803-9488 .- 1502-4725. ; 58:5, s. 383-8
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Tidskriftsartikel (refereegranskat)abstract
- The present study assessed mental well-being daily in 28 alcohol-dependent patients who underwent 28 days of Minnesota inpatient treatment. The Swedish Mood Adjective Check List (sMACL) with six bipolar dimensions was used for daily self-reports. At start of treatment, patients had lower levels in four dimensions of mental well-being compared to those of a norm group. Moreover, patients showed significant improvements in all levels of mental well-being during treatment, and at the end of treatment patients had values within the normal range, except for one dimension (activation/deactivation), in which the levels were significantly higher. The findings may suggest a beneficial effect of this type of treatment on mental well-being, although findings may also reflect a mere effect of adjustment to treatment or the social situation.
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| 16. |
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| 17. |
- Bylund, Johan, 1975, et al.
(författare)
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Cytochalasin B triggers a novel pertussis toxin sensitive pathway in TNF-alpha primed neutrophils
- 2004
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Ingår i: BMC cell biology. - 1471-2121. ; 5
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Cytochalasin B does not directly activate the oxygen-radical-producing NADPH oxidase activity of neutrophils but transfers desensitized G-protein coupled receptors (GPCR) into an active signaling state by uncoupling GCPR from the cytoskeleton. The receptor uncoupling results in respiratory burst activity when signals generated by reactivated formyl peptide receptors trigger the NADPH-oxidase to produce superoxide anions. RESULTS: Tumor necrosis factor alpha (TNF-alpha) primes neutrophils for subsequent activation by cytochalasin B. Pretreatment with TNF-alpha induced mobilization of receptor-storing neutrophil organelles, suggesting that receptor up-regulation significantly contributes to the response, but the receptor mobilization was not sufficient for induction of the cytochalasin B sensitive state. The TNF-alpha primed state resembled that of the desensitized non-signaling state of agonist-occupied neutrophil formyl peptide receptors. The fact that the TNF-alpha primed, cytochalasin B-triggered activation process was pertussis toxin sensitive suggests that the activation process involves a GPCR. Based on desensitization experiments the unidentified receptor was found to be distinct from the C5a receptor as well as the formyl peptide receptor family members FPR and FPRL1. Based on the fact the occupied and desensitized receptors for interleukin-8 and platelet activating factor could not be reactivated by cytochalasin B, also these could be excluded as receptor candidates involved in the TNF-alpha primed state. CONCLUSIONS: The TNF-alpha-induced priming signals could possibly trigger a release of an endogenous GPCR-agonist, amplifying the response to the receptor-uncoupling effect of cytochalasin B. However, no such substance could be found, suggesting that TNF-alpha can transfer G-protein coupled receptors to a signaling state independently of agonist binding.
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| 18. |
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| 19. |
- Carlsson, Arne, et al.
(författare)
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Emissionsmodell för tunnlar
- 2004
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Tunnels for road and street traffic become increasingly important for transport provisions, primarily in large cities. Currently, there are in Stockholm and Gothenburg high-volume tunnels in the primary road network. In addition, many new tunnels will soon be finalised or are planned both in Stockholm and Gothenburg. The exhaust emissions in road tunnels may not exceed certain limits. Road tunnels are equipped with ventilation systems to make sure that limits for air quality are not exceeded, primarily emissions of NO2. The ventilation systems are dimensioned using data on maximum expected emissions per unit of time. VTI has obtained a commission from the Swedish National Road Administration (SNRA) to develop a model for calculation of exhaust emissions in tunnels, which in addition shall take into account oversaturated conditions. Currently, SNRA has no satisfactory model for calculations at hourly level. The objective of the development effort has been to formulate a calculation model for travel speeds and emissions in motorway tunnels, to be used when tunnel ventilation systems are dimensioned. For a complete structure, the model shall provide individual tunnel tube emission data for hourly traffic, split upon homogenous - from the viewpoint of traffic engineering - road links and ventilation segments. This report describes the results of the development project for calculation of emissions in tunnels. The completed model comprises two parts, one for calculation of speed and corresponding hourly flow at given demand level and one for calculation of emissions, using hourly flows and speed as input data. For each part, there is a computer program with user manual. Test runs of the model for some basic typical tunnel cases, has been carried out to illustrate the results of the total model. The total emissions of NOx (kg/km) as a function of traffic flow have been calculated for different degree of traffic load. In addition, the model has been validated by comparisons of calculated NOx values from the model with measured NOx values in three different tunnels: the Gnistäng tunnel and the Tingstad tunnel in Gothenburg and the Southern Route tunnel in Stockholm.
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| 20. |
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| 21. |
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| 22. |
- Davila, M. E., et al.
(författare)
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Surface phase transitions at metal-semiconductor interfaces : a revisit is needed
- 2004
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Ingår i: Applied Surface Science. - : Elsevier BV. - 0169-4332 .- 1873-5584. ; 234:04-jan, s. 274-285
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Tidskriftsartikel (refereegranskat)abstract
- In this article, we review some of the most recent progress and understanding in the low temperature surface phase transitions at prototypical metal-semiconductor interfaces. We essentially focus on quantitative surface structural information obtained by using a significant variety of specialised techniques for the individual phases of a model system, namely, tin on Ge(1 1 1) substrates. The strengths and limitations of the structural results obtained by using scanning tunnelling microscopy, photoelectron diffraction and surface X-ray diffraction are discussed in relation to their support with respect to possible mechanisms recently invoked in the literature as being at the origin of the phase transition. These investigations show that a large progress has been made in this field, taking into account the very valuable experimental and theoretical contributions provided by different groups. There remain, however, essential unresolved problems, which will be analysed in the light of the limitations of these structural methods and the difficulty presented by the complex adsorbate systems studied.
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| 23. |
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| 24. |
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| 25. |
- Engquist, Bo, et al.
(författare)
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Simplified methods of implant treatment in the edentulous lower jaw. A controlled prospective study. Part I : one-stage versus two-stage surgery.
- 2002
-
Ingår i: Clinical Implant Dentistry and Related Research. - 1523-0899 .- 1708-8208. ; 4:2, s. 93-103
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: The original protocol for Brσnemark System implants in the mandible was a two-stage procedure with 3 months healing time. With five or six implants and a cast framework of gold, the treatment is rather expensive, and simplified methods would be desirable. PURPOSE: The goal of this controlled serial study was to investigate the outcome of a simplified procedure with one-stage surgery, four Brσnemark implants, shortened healing time, and a new titanium-acrylic fixed full prosthesis. MATERIALS AND METHODS: Eighty-two patients were treated in three different groups at two specialist centers. All patients were provided with four implants, loaded with a Procera All-in-One bridge (Nobel Biocare, Gothenburg, Sweden) after 12 weeks. In group A (n = 30), one-stage surgery was combined with two-piece implants. In group B (n = 30), the control group, two-stage surgery and two-piece implants were used. In group C (n = 22), one-stage surgery was combined with one-piece implants. Marginal bone level was rated from radiographs at implant insertion, at baseline, and after 1 year. RESULTS: The survival rate after 1 year for group A was 93.3%, group B, 97.5%, and group C, 93.2%. The differences were not statistically significant. Between fixture insertion and baseline, the average bone loss for group A was 1.2 mm, group B, 1.3 mm, and group C, 1.3 mm. No complications in the form of bridge loosening or acrylic fractures were recorded during the first year. CONCLUSIONS: The survival rates and the marginal bone changes did not differ significantly between the one-stage groups and the control group. The survival rate and the marginal bone changes were similar for one-piece and two-piece implants. Four implants were sufficient to support full fixed prostheses in the mandibles. The Procera All-in-One bridges proved to be of high quality, and no complications were experienced. key words: endosseous implants, nonsubmerged implants, one-piece implants, prospective clinical study, submerged implants
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| 26. |
- Engquist, Bo, et al.
(författare)
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Simplified methods of implant treatment in the edentulous lower jaw. Part II : Early loading
- 2004
-
Ingår i: Clinical Implant Dentistry and Related Research. - 1523-0899 .- 1708-8208. ; 6:2, s. 90-100
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Tidskriftsartikel (refereegranskat)abstract
- Background: Most implant treatment is performed with a two-stage surgical procedure. A disadvantage of these implant treatments is that they are time-consuming. Purpose: The aim of the present study was to evaluate the results of early loading in the edentulous mandible and to compare those results with treatment results of one-stage surgery followed by a healing period and with two-stage surgery. Material and Methods: The material comprises four treatment groups with a total of 108 patients with edentulous lower jaws and 432 implants. All patients were treated with Brånemark implants (Nobel Biocare AB, Gothenburg, Sweden) with a turned surface and fixed prostheses in the lower jaw, supported by four implants. The patients in group A were treated with a one-stage procedure, a two-piece implant, and a 3-month healing period before loading. Group B (control group) had a two-stage procedure, a two-piece implant, and a 3-month healing period. Group C had a one-stage procedure, a one-piece implant, and a 3-month healing period. Group D was treated with a one-stage surgical procedure, a two-piece implant, and early loading (within 3 weeks). All patients were provided with a Procera® Implant Bridge (Nobel Biocare) with a framework made by computer-assisted milling of one piece of pure titanium. All patients have been followed up for 1 year. Results: The survival rates were 93.2 to 93.3% in the experimental groups and 97.5% in the control group. The difference was not statistically significant. The measurements of the marginal bone level demonstrated a mean bone loss of 0.8 mm between fixture insertion and the 1-year examination in patients with early loading (group D) whereas the bone loss in patients who underwent a healing period before loading was 1.3 to 1.6 mm. The difference between the control group and the group with early loading was significant. Conclusions: Survival rates for patients treated with a one-stage procedure were lower than survival rates for patients treated according to a "classical concept," but the differences were not statistically significant. There was no difference between treatment results with one-piece and two-piece implants. The implant loss in patients with early loading was probably caused by overloading, and careful supervision of occlusal loading is recommended. Early loading gave significantly less marginal bone loss when compared with two-stage surgery.
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| 27. |
- Eriksson, Ulf G, et al.
(författare)
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Pharmacokinetics of melagatran and the effect on ex vivo coagulation time in orthopaedic surgery patients receiving subcutaneous melagatran and oral ximelagatran : a population model analysis
- 2003
-
Ingår i: Clinical Pharmacokinetics. - 0312-5963 .- 1179-1926. ; 42:7, s. 687-701
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Forskningsöversikt (refereegranskat)abstract
- OBJECTIVE: Ximelagatran, an oral direct thrombin inhibitor, is rapidly bioconverted to melagatran, its active form. The objective of this population analysis was to characterise the pharmacokinetics of melagatran and its effect on activated partial thromboplastin time (APTT), an ex vivo measure of coagulation time, in orthopaedic surgery patients sequentially receiving subcutaneous melagatran and oral ximelagatran as prophylaxis for venous thromboembolism. To support the design of a pivotal dose-finding study, the impact of individualised dosage based on bodyweight and calculated creatinine clearance was examined. DESIGN AND METHODS: Pooled data obtained in three small dose-guiding studies were analysed. The patients received twice-daily administration, with either subcutaneous melagatran alone or a sequential regimen of subcutaneous melagatran followed by oral ximelagatran, for 8-11 days starting just before initiation of surgery. Nonlinear mixed-effects modelling was used to evaluate rich data of melagatran pharmacokinetics (3326 observations) and the pharmacodynamic effect on APTT (2319 observations) in samples from 216 patients collected in the three dose-guiding trials. The pharmacokinetic and pharmacodynamic models were validated using sparse data collected in a subgroup of 319 patients enrolled in the pivotal dose-finding trial. The impact of individualised dosage on pharmacokinetic and pharmacodynamic variability was evaluated by simulations of the pharmacokinetic-pharmacodynamic model. RESULTS: The pharmacokinetics of melagatran were well described by a one-compartment model with first-order absorption after both subcutaneous melagatran and oral ximelagatran. Melagatran clearance was correlated with renal function, assessed as calculated creatinine clearance. The median population clearance (creatinine clearance 70 mL/min) was 5.3 and 22.9 L/h for the subcutaneous and oral formulations, respectively. The bioavailability of melagatran after oral ximelagatran relative to subcutaneous melagatran was 23%. The volume of distribution was influenced by bodyweight. For a patient with a bodyweight of 75kg, the median population estimates were 15.5 and 159L for the subcutaneous and oral formulations, respectively. The relationship between APTT and melagatran plasma concentration was well described by a power function, with a steeper slope during and early after surgery but no influence by any covariates. Simulations demonstrated that individualised dosage based on creatinine clearance or bodyweight had no clinically relevant impact on the variability in melagatran pharmacokinetics or on the effect on APTT. CONCLUSIONS: The relatively low impact of individualised dosage on the pharmacokinetic and pharmacodynamic variability of melagatran supported the use of a fixed-dose regimen in the studied population of orthopaedic surgery patients, including those with mild to moderate renal impairment.
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| 28. |
- Everberg, Henrik, et al.
(författare)
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Protein pre-fractionation in detergent-polymer aqueous two-phase systems for facilitated proteomic studies of membrane proteins
- 2004
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Ingår i: Journal of Chromatography A. - : Elsevier BV. - 0021-9673. ; 1029:1-2, s. 113-124
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Tidskriftsartikel (refereegranskat)abstract
- Pre-fractionation of a complex mixture of proteins increases the resolution in analytical separations of proteins from cells, tissues or organisms. Here we demonstrate a novel method for pre-fractionation of membrane proteins by a detergent-based aqueous two-phase system. Membrane proteins are strongly under-represented in proteomic studies based on two-dimensional electrophoresis (2-DE). As a model system, we have isolated mitochondria from the yeast Saccharomyces cerevisiae. Mitochondrial proteins were fractionated in an aqueous two-phase system consisting of the polymer poly(ethylene glycol) and either of two commonly used non-ionic detergents, Triton X-114 or dodecyl maltoside (DDM). Soluble proteins partitioned mainly to the polymer phase while membrane proteins were enriched in the detergent phase, as identified from one-dimensional electrophoresis (I-DE) and/or 2-DE followed by mass spectrometric analysis. Pre-fractionation was further enhanced by addition of an anionic detergent, sodium dodecyl sulfate, or a chaotropic salt, NaClO4, and by raising the pH in the system. The two-phase system pre-fractionation was furthermore combined with an alternative two-dimensional high-resolution separation method, namely ion-exchange chromatography and 1-DE. By this approach a larger number of membrane proteins could be identified compared to separation with conventional 2-DE. Thus, pre-fractionation of complex protein mixtures using the aqueous two-phase systems developed here will help to disclose larger proportions of membrane proteins in different proteomes. (C) 2004 Elsevier B.V. All rights reserved.
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| 29. |
- Fateh-Alavi, Kamyar, et al.
(författare)
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A rapid microwave-assisted solvent extraction method for assessment of stabilizer concentration in crosslinked polydimethylsiloxane
- 2004
-
Ingår i: Journal of Applied Polymer Science. - : Wiley. - 0021-8995 .- 1097-4628. ; 93:5, s. 2185-2192
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Tidskriftsartikel (refereegranskat)abstract
- Crosslinked polyclimethylsiloxanes were prepared containing 0.05 to 0.2 wt % of either a phenolic antioxidant (Irganox(R) 1010) or a hindered amine stabilizer (Tinuvin(R) 144). The stabilizer concentration was assessed by HPLC and UV-Vis spectroscopy of Soxhlet and microwave-assisted solvent extracts. Almost complete recovery of stabilizer was achieved with Soxhlet extraction. High stabilizer recovery was achieved when acetone was used as the solvent in the microwave-assisted extraction. HPLC was shown to be an efficient method for determining the concentration of Irganox 1010. For Tinuvin 144 the selectivity of both UV-Vis spectroscopy and HPLC was poor, leading to imprecise evaluation of the antioxidant concentration. The loss of stabilizer by migration from polymer to hot water (75 and 95degreesC) was monitored for the systems stabilized with Irganox 1010 and the diffusion coefficient of the antioxidant in the polymer was determined.
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| 30. |
- Fateh-Alavi, K., et al.
(författare)
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The effect of stabilizer concentration on the air-plasma-induced surface oxidation of crosslinked polydimethylsiloxane
- 2002
-
Ingår i: Polymer degradation and stability. - 0141-3910 .- 1873-2321. ; 78:1, s. 17-25
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Tidskriftsartikel (refereegranskat)abstract
- The concentrations of three stabilizers-a hindered phenol (Irganox 1076), a hindered amine light stabilizer (Tinuvin 770) and a bifunctional stabilizer with chain-breaking hindered phenol and secondary amine and hydroperoxide-decomposing sulphide moieties (Irganox 565)-in crosslinked polydimethylsiloxane were varied using swelling solutions of the stabilizers at different concentrations. The concentration of the stabilizer in the rubber was assessed by UV-Vis spectroscopy of Soxhlet and microwave assisted extracts. Irganox 1076 and Tinuvin 770 were soluble in polydimethylsiloxane to at least 0.2-0.3 wt.%, whereas the solubility of Irganox 565 was considerably lower. The samples were exposed to GHz air plasma and the surface structures of the exposed samples were studied by X-ray photoelectron spectroscopy, and by optical and scanning electron microscopy after uniaxial stretching. The plasma exposure time required for the formation of an oxidised glassy layer increased in a linear fashion with increasing stabilizer concentration, suggesting that the consumption rate was constant in time during the plasma exposure. Tinuvin 770 showed the strongest overall protecting effect whereas Irganox 565 showed the strongest protecting effect per mass fraction of stabilizer. Irganox 1076 was of moderate efficiency. The results suggest that efficient protection towards air plasma is achieved with hindered amine stabilizers or with stabilizers combining chain-breaking and hydroperoxide-decomposing functions. Differential scanning calorimetry showed that Tinuvin 770 and Irganox 565 protected polydimethylsiloxane against thermal oxidation at elevated temperatures. The chemical consumption of these stabilizers followed basically the classical scheme with zero-order kinetics and a rate constant obeying the Arrhenius law.
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| 31. |
- Glendor, Ulf, et al.
(författare)
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Direct and indirect time spent on care of dental trauma : a 2-year prospective study of children and adolescents
- 2000
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Ingår i: Endodontics and dental traumatology. - : Wiley. - 0109-2502 .- 1600-4469 .- 1600-9657. ; 16:1, s. 16-23
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Tidskriftsartikel (refereegranskat)abstract
- The aim was to account for the total time spent by professional care-givers (direct time) and by patients and companions engaged as support and help (indirect time) to treat and otherwise attend to children and adolescents with dental trauma to primary and permanent teeth. The study was based on a random sample of 192 children and adolescents with dental traumas reported to an insurance company and prospectively followed up by telephone interviews over a period of 2 years after the trauma episode. On average, direct time represented 16% of total time for all visits for dental trauma to permanent teeth and 11% for trauma to primary teeth. The most extensive type of indirect time was transport time, which took up 30% of the total time spent on injuries to permanent teeth and 36% for injuries to primary teeth. Multiple regression analysis of the impact of dental and demographic injury variables on the time variables showed that complicated trauma was associated with extended time, direct as well as indirect, for permanent and primary teeth injuries. Our estimate of the average relative increase in total time spent by patients and companions in cases of complicated injury to permanent teeth was 117% (95% confidence interval [CI], 52-211) for patients and 112% (95% CI, 42-217) for companions. For transport time a strong predictor was access to a dental clinic near the place of residence. Lack of access could extend the average transport time by 180% (95% CI, 80-335) for patients and 163% (95% CI, 67-317) for their companions in cases of injuries to primary teeth.
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| 32. |
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| 33. |
- Grehk, Mikael, et al.
(författare)
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Li-induced phase transition from the Ge(111)3x1:Li surface reconstruction to the Ge(111)rot3xrot3:Li lithium germanid
- 2000
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - : American Physical Society. - 1098-0121 .- 1550-235X. ; 61:7, s. 4963-4967
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Tidskriftsartikel (refereegranskat)abstract
- We have investigated the Li-induced phase transition from the Ge(111)3×1:Li to the Ge(111)sqrt[3]×sqrt[3]:Li reconstruction with photoemission. The Ge(111)3×1:Li reconstruction can be described as parallel rows of Ge atoms separated by single rows of Li atoms. The Ge(111)sqrt[3]×sqrt[3]:Li reconstruction, on the other hands, has to be described in terms of a Li-germanide phase extending over at least two atomic layers.
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| 34. |
- Grehk, T. M., et al.
(författare)
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Li-induced phase transition from the Ge(111)3X1 : Li surface reconstruction to the Ge(111)root 3X root 3 : Li lithium germanide
- 2000
-
Ingår i: Physical Review B. Condensed Matter and Materials Physics. - 1098-0121 .- 1550-235X. ; 61:7, s. 4963-4967
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Tidskriftsartikel (refereegranskat)abstract
- We have investigated the Li-induced phase transition from the Ge(111)3X1:Li to the Ge(111)root 3X root 3:Li reconstruction with photoemission. The Ge(111)3X1:Li reconstruction can be described as parallel rows of Ge atoms separated by single rows of Li atoms. The Ge(111)root 3X root 3:Li reconstruction, on the other hands, has to be described in terms of a Li-germanide phase extending over at least two atomic layers.
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| 35. |
- Grishin, Michael A., et al.
(författare)
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High performance films of binary system SrTiO3-PbZr0.52Ti0.48O3 on sapphire
- 2001
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Ingår i: Integrated Ferroelectrics. - : Informa UK Limited. - 1058-4587 .- 1607-8489. ; 39:1-4, s. 351-358
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Tidskriftsartikel (refereegranskat)abstract
- Continuous series of solid solutions x.SrTiO3-(1-x).PbZr0.52Ti0.48O3 (SPZT) have been grown by pulsed laser deposition technique onto La0.7Sr0.3CoO3/Al2O3(01 (1) under bar2) single crystal. Films properties have been characterized in Au/SPZT/La0.7Sr0.3CoO3(LSCO)/Al2O3 vertical capacitive cell. X-ray diffraction shows SPZT/LSCO bilayer grows in strict epitaxial relationship with sapphire substrate: (001) SPZT parallel to (001) LSCO parallel to (01 (1) under bar2) Al2O3; [010] SPZT parallel to [010] LSCO parallel to [421] Al2O3. LSCO layer was found to be tensile strained, while SPZT film experiences tetragonal distortions c/a -1 approximate to 0.86% which are much lower than 2.73% in pure PZT ceramics. Curie temperature in SPZT film has been tailored continuously in the explored temperature range 77 K to 400 K by controlling SrTiO3:PZT ratio. Processing parameters have been optimized to get the highest tunability factor K = epsilon'(0) - epsilon'(V)/epsilon'(0) x 1/tandelta . SrTiO3:PZT=83:17 film exhibits superior properties: at I kHz maximum dielectric perinittivity and minimum loss tandelta were found to be 870 and 0.005, respectively; while K-factor exceeds value of 60 in the temperature range 280 to 350 degreesC reaching the maximum value of 64 at 325 degreesC. SPZT films can withstand prolonged pre-breakdown electric field and has resistivity as high as 3.5 10(12) Omega cm at 186 kV/cm.
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| 36. |
- Gustavsson, T. G., et al.
(författare)
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Aging of silicone rubber under ac or dc voltages in a coastal environment
- 2001
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Ingår i: IEEE transactions on dielectrics and electrical insulation. - : Institute of Electrical and Electronics Engineers (IEEE). - 1070-9878 .- 1558-4135. ; 8:6, s. 1029-1039
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Tidskriftsartikel (refereegranskat)abstract
- Material samples of silicone rubber with known differences in their composition, i.e. different filler content and extra silicone oil added, have been aged at the Anneberg field station on the west coast of Sweden. ac or dc voltage supplied to cylindrical samples at stress levels of 50 or 100 V/mm. The work includes laboratory examination of material changes together with on-site, visual observations and leakage current measurements. Material samplings for the laboratory tests were made after 18 months of electrical aging, which went on for one more year in order to gather further information on the long-term electrical performance of the material. The dominant aging factor was the level of the applied stress, independent of ac or dc voltage. The dc stressed samples showed a higher leakage current and exhibited larger surface degradation compared with samples exposed to ac voltage. The material parameter, an addition of extra silicone oil, initially lead to an increase in adhesion of pollutants, whereas the overall performance was improved by the higher suppression of the leakage current related to oligomer diffusion. Samples with lower level of alumina trihydrate (ATH) exhibited a delayed onset of degradation, but once damaged they degraded more rapidly than the specimens with a higher ATH content. Infrared spectroscopy showed that the ATH was completely consumed at the eroded surface regions. The aging of the surfaces was further assessed by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). The low molar mass siloxanes present in the pollution layer were extracted and analyzed by size exclusion chromatography and gas chromatography-mass spectroscopy. The results indicated that the main degradation factor was thermal depolymerization activated by electrical discharges. Oxidative crosslinking of the silicone rubber, usually attributed to surface close corona discharges, appeared to have played a minor role.
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| 37. |
- Göthelid, Mats, et al.
(författare)
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An ordered layer of molecular iodine on Ge(100) 2x1
- 2004
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Ingår i: Surface Science. - : Elsevier BV. - 0039-6028 .- 1879-2758. ; 556:03-feb, s. 203-212
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Tidskriftsartikel (refereegranskat)abstract
- Adsorption of iodine on the Ge(1 0 0) (2 x 1) surface has been investigated by core level and valence band photoelectron spectroscopy and scanning tunnelling microscopy. Iodine binds to dimer atom dangling bonds without disrupting the dimers at all coverages. At saturation a c(2 x 2) ordered layer of molecular iodine develops on top of a (2 x 2) ordered structure of atomic iodine binding to asymmetric Ge-dimers. Annealing destroys the molecular character and etches the surface by Ge dimer bond breaking and attachment of additional iodine to these Ge atoms to form GeI2, which desorbs from the surface.
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| 38. |
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| 39. |
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| 40. |
- Helmfrid, Ingela, et al.
(författare)
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Miljögifter i blod hos högkonsumenter av Vätternfisk
- 2003
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Blodprover från kvinnliga "Vätternfiskkonsumenter" har bestämts med avseende på halten av polyklorerade bifenyler (PCB), 1,1-diklor-2,2-bis(4-klordifenyl)etylen (DDE), Hexaklorben-sen (HCB), hexaklor cyklohexan (HCH), Polybromerade difenyletrar (PBDE) och kvicksilver (Hg). Gruppen bestod av 37 kvinnor som var fritidsfiskare eller fruar till fritids- eller yrkes-fiskare. Halterna jämfördes med kontroller och förutom analys av blodets halt av miljögifter kartlades också gruppens dietvanor med hjälp av en kostenkät.Resultaten visar att halterna av samtliga miljögifter med undantag av HCB var högre hos Vät-ternfiskkonsumenter än i kontrollgrupperna. Halten av PCB 153 (en variant av PCB) låg un-gefär i samma nivå (115-625 ng/g fett) som tidigare rapporterats hos fruar till fiskare på ost-kusten (151-463 ng/g fett) då personer i samma åldersgrupp jämförs (37-59 år). Vid jämförel-ser av medelvärden utan hänsyn till ålder, hade kvinnor som konsumerar fisk från Vättern högre halter (354 ng/g fett) än som har rapporterats i en studie av fruar till fiskare på ostkusten (160 ng/g fett). De höga halterna beror på att flertalet av deltagarna i denna studie är äldre och att blodets halt av PCB, DDE och HCB ökar med stigande ålder.Blodets medianhalter av den ingående varianten i flamskyddsmedel, BDE 47 var generellt låg men var något högre bland Vätternfiskkonsumenter jämfört med kontrollen (3,6 respekti-ve 2,9 ng/g fett). Fiskkonsumtion anses enligt tidigare studier vara en viktig orsak till att PBDEs som används som flamskyddsmedel samlas i kroppen.Medelvärdet av halten metylkvicksilver hos Vätternfiskkonsumenter var 9,4 μg/l vilket är 3-5 gånger högre än den hos kontrollgrupperna (2,6 μg/l respektive 1,6 μg/l). Förklaringen är sannolikt Vätternfiskkonsumenternas höga konsumtionen av både mager (abborre, gädda) och fet (lax, röding, öring) rovfisk under flera års tid. Samtliga Vätternfiskkonsumenter med halter över 19μg/l i blodet åt främst abborre och/eller lax, röding, öring 1-3 gånger vecka. Andra studier har tidigare visat att nervsystemet hos foster kan påverkas om mödrarna har kvicksil-verhalter över 10 μg/l och flera kvinnor i denna studie hade alltså halter som översteg detta värde.Även om halterna av främst PCB och metylkvicksilver i blodet hos Vätternfiskkonsumenter är höga är det inte motiverat att avråda äldre personer eller kvinnor som inte tänker skaffa fler barn att äta fet fisk. Tvärtom, nyttan med sådan fisk överväger. Den feta fisken innehåller Omega-3-fettsyror som minskar risken för hjärt- och kärlsjukdomar. Däremot indikerar fyn-den i denna undersökning att kvinnor i barnafödande ålder ej bör äta stora mängder av framför allt abborre och fet fisk från Vättern.
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| 41. |
- Hillborg, H., et al.
(författare)
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Characterisation of low molar mass siloxanes extracted from crosslinked polydimethylsiloxanes exposed to corona discharges
- 2001
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Ingår i: Polymer. - 0032-3861 .- 1873-2291. ; 42:21, s. 8883-8889
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Tidskriftsartikel (refereegranskat)abstract
- Crosslinked polydimethylsiloxanes were exposed to corona discharges in dry air at normal pressure. Short-time solvent extraction and subsequent analysis of the extractables, by gas chromatography, mass spectrometry and size exclusion chromatography showed that, oligomers consisting mainly of cyclics with 4-9 repeating units were formed during corona exposure. The size distribution of the oligomers was independent of the crosslink density and corona exposure time. The amount of oligomers located at the surface increased, with increasing storage time, after the corona exposure in qualitative agreement with the ongoing hydrophobic recovery process. Longer extractions penetrated deeper into the samples, and, in addition to the cyclic oligomers, higher molar mass species (similar to 50,000 g mol(-1) for unexposed samples) were detected. Samples exposed to corona, treated in this way, showed a broadening of the high molar mass peak towards lower molar masses.
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| 42. |
-
Historien är nu. En introduktion till historiedidaktiken
- 2004
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Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- The book is an introduction to the field of history didactics, which focuses on problems related to the communication of history and on the position of the historical dimension in society.
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| 43. |
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| 44. |
- Janin, Emmanuelle, et al.
(författare)
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Adsorption and bonding of propene and 2-butenal on Pt(111)
- 2001
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Ingår i: Surface Science. - 0039-6028 .- 1879-2758. ; 482, s. 83-89
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Tidskriftsartikel (refereegranskat)abstract
- The adsorption of propene and 2-butenal on the Pt(1 1 1) surface has been studied by high resolution photoelectron spectroscopy, both in the mono-and multi-layer regime. The results obtained indicate an involvement of both aliphatic and carbonyl groups in the bonding of 2-butenal with the platinum surface in the sub-monolayer regime.
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| 45. |
- Janin, E., et al.
(författare)
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Corrosive adsorption of Sn on the Pt(110)(1 x 2) surface
- 2002
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Ingår i: Surface Science. - 0039-6028 .- 1879-2758. ; 515:03-feb, s. 462-470
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Tidskriftsartikel (refereegranskat)abstract
- Room temperature deposition of Sn on the Pt(110)(1 x 2) surface has been studied by scanning tunnelling microscopy and core level photoelectron spectroscopy. At low coverage Sri is found in three different configurations; as mobile adatoms in the valley of the missing-row reconstruction, as 1D-Pt-Sn-Pt- alloy chains forming local Pt3Sn(110)2 x 2 regions and finally as 3D alloy islands. At higher coverage these islands form a platinum rich alloy film, which is dissolved in the crystal upon annealing to 600 degreesC.
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| 46. |
- Jansson, Kjell, 1956-, et al.
(författare)
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The value of repeated echocardiographic evaluation in patients with idiopathic dilated cardiomyopathy during treatment with metoprolol or captopril
- 2000
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Ingår i: Scandinavian Cardiovascular Journal. - 1401-7431 .- 1651-2006. ; 34:3, s. 293-300
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Tidskriftsartikel (refereegranskat)abstract
- Serial echocardiographic investigations were carried out on patients with idiopathic dilated cardiomyopathy, to evaluate treatment effects on left ventricular (LV) performance during therapy with either metoprolol or captopril. Thirty-two patients (23 males and 9 females) with mild to moderate symptoms of heart failure (NYHA II-III) and a mean age of 49 years were included in the investigation. The patients were investigated with Doppler echocardiography before treatment, after 3 and 6 months of treatment (either metoprolol or captopril) and 1 month after withdrawal of treatment. Intra- and inter-investigator reproducibility was acceptable, with a coefficient of variation of less than 5% for LV dimensions. A reduction in LV dimensions was seen in both treatment groups. In the metoprolol group there was also an increase in LV stroke volume and fractional shortening. The non-invasive data were in accordance with invasive measurements of stroke volume and LV filling pressure. In patients with idiopathic dilated cardiomyopathy and mild to moderate symptoms of heart failure, echocardiography seemed to be sufficiently reproducible to be used for determination of treatment effects in a longitudinal heart failure study. Both metoprolol and captopril were well tolerated and had favourable effects on LV performance.
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| 47. |
- Jansson, S. E. A., et al.
(författare)
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Packaging materials for fermented milk Part 2 : Solute-induced changes and effects of material polarity and thickness on food quality
- 2002
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Ingår i: Packaging technology & science. - : Wiley. - 0894-3214 .- 1099-1522. ; 15:6, s. 287-300
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Tidskriftsartikel (refereegranskat)abstract
- This work is a continuation of the application of a developed methodology for the selection of packaging material for a specific food product, in this case the 'demanding' food product. fermented milk. The effects of different packaging material parameters on the quality of fermented milk were studied. Food quality after storage was determined as a function of material polarity and pouch thickness by storing the liquid in pouches of different materials. The material polarity was varied by using laminates with polyethylene, poly(ethylene-co-vinyl alcohol) with two different ethylene contents and an aliphatic polyketone. The effects of pouch thickness were studied using high-density polyethylene films of different thicknesses between 25 mum and 200 mum. The interactions between the milk product and the pouch material were analysed by oxygen and water permeability, gas chromatography-mass spectrometry and tensile testing. The CO2 and O-2 contents in the headspace of the pouches were determined. The food quality was determined by measuring whey syneresis and the contents of Bifidobacteria, Enterobacteriaceae, yeast and mould. A trained taste panel determined the sensory properties. The content of CO2, and consequently the sparkling taste, increased with increasing polarity and/or pouch thickness. The CO2 content was affected more easily by changes in material polarity than by changes in pouch thickness. The increase in whey syneresis and the decrease in Bifidobacteria content with time were independent Of material polarity and pouch thickness. The contents Of Enterobacteriaceae, yeast and mould in the liquid were always below existing limits for foodstuffs. A newly developed method was used by which the CO2 and 02 permeabilities of the pouch/packaging could be estimated, using the kinetics of the gas composition in the pouch headspace. Permeability values, as estimated by the method, revealed that the CO2 production and the O-2 consumption rates of the fermented milk were dependent on the CO2 and O-2 headspace concentrations. An increase in permeability, determined by conventional methods, suggested that both the non-polar and the polar polymers were plasticized by fermented milk. The plasticization was, however, modest and undetectable when the polyethylene tensile test data were analysed.
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| 48. |
- Jemt, Torsten, 1950, et al.
(författare)
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Implant-supported welded titanium frameworks in the edentulous maxilla: a 5-year prospective multicenter study.
- 2002
-
Ingår i: The International journal of prosthodontics. - 0893-2174. ; 15:6, s. 544-8
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: This study evaluated the 5-year clinical and radiographic performance of fixed implant-supported maxillary prostheses with either welded titanium or conventional cast-gold alloy frameworks. MATERIALS AND METHODS: Fifty-eight consecutive patients were provided with 349 osseointegrated Brånemark system implants in the edentulous maxilla at six different implant centers. Twenty-eight of the patients received, at random, prostheses with laser-welded titanium frameworks, and the remaining 30 patients had prostheses with conventional cast-gold alloy frameworks. Clinical and radiographic data were collected for 5 years after prosthesis placement. RESULTS: The titanium and cast-gold framework groups exhibited similar cumulative survival and success rates (CSR). The 5-year implant CSR from time of placement was 91.4% and 94.0%, respectively, and from prosthesis delivery the rate was 94.9% and 95.6%, respectively. The corresponding 5-year prosthesis CSRs were 96.4% and 93.3%. One patient from each group lost all the implants and turned to complete dentures within the first year of function. Another patient with a cast-gold framework had the prosthesis replaced after 4 years, basically because of problems with the veneering material. No fractures of implant components were observed during the follow-up period. Bone loss was on average 0.59 mm (SD 0.97 mm) during 5 years, with no statistical difference between the two groups. CONCLUSION: Welded titanium frameworks presented a similar favorable clinical performance as conventional cast-gold alloy frameworks in fixed implant-supported prostheses in the edentulous maxilla after 5 years in function. Implant failures were concentrated in only a few patients in each study group.
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| 49. |
- Johansson, Åsa, et al.
(författare)
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A novel method for automatic genotyping of microsatellite markers based on parametric pattern recognition
- 2003
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Ingår i: Human Genetics. - : Springer Science and Business Media LLC. - 0340-6717 .- 1432-1203. ; 113:4, s. 316-324
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Tidskriftsartikel (refereegranskat)abstract
- Genetic mapping of loci affecting complex phenotypes in human and other organisms is presently being conducted on a very large scale, using either microsatellite or single nucleotide polymorphism (SNP) markers and by partly automated methods. A critical step in this process is the conversion of the instrument output into genotypes, both a time-consuming and error prone procedure. Errors made during this calling of genotypes will dramatically reduce the ability to map the location of loci underlying a phenotype. Accurate methods for automatic genotype calling are therefore important. Here, we describe novel algorithms for automatic calling of microsatellite genotypes using parametric pattern recognition. The analysis of microsatellite data is complicated both by the occurrence of stutter bands, which arise from Taq polymerase misreading the number of repeats, and additional bands derived form the non-template dependent addition of a nucleotide to the 3' end of the PCR products. These problems, together with the fact that the lengths of two alleles in a heterozygous individual may differ by only two nucleotides, complicate the development of an automated process. The novel algorithms markedly reduce the need for manual editing and the frequency of miscalls, and compares very favourably with commercially available software for automatic microsatellite genotyping.
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| 50. |
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