| 1. |
- Ekblom, Kim, 1970-, et al.
(författare)
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Iron stores and HFE genotypes are not related to increased risk of ischemic stroke. : a prospective nested case-referent study
- 2007
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Ingår i: Cerebrovascular Diseases. - : S. Karger AG. - 1015-9770 .- 1421-9786. ; 24:5, s. 405-411
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Tidskriftsartikel (refereegranskat)abstract
- Background: High iron levels can increase the formation of noxious oxygen radicals, which are thought to contribute to cerebrovascular disease. The aim of this prospective study was to determine if iron status and HFE genotypes constitute risk factors for stroke. Methods: First-ever stroke cases (231 ischemic and 42 hemorrhagic) and matched double referents from the population-based Northern Sweden cohorts were studied in a nested case-referent setting. Results: For total iron binding capacity, an increased risk of ischemic stroke was seen in the highest quartile (OR 1.80; 95% CI 1.14-2.83; p for trend 0.012). The highest quartile of transferrin iron saturation showed a decreased risk of ischemic stroke in men (OR 0.44; 95% CI 0.22-0.87; p for trend 0.028), but not in women. There was an increased risk of hemorrhagic stroke in the second (OR 4.07; 95% CI 1.09-15.20) and third quartile (OR 4.22; 95% CI 1.08-16.42) of ferritin. Neither quartiles of plasma iron concentrations nor the HFE C282Y and H63D genotypes were associated with ischemic or hemorrhagic stroke. Conclusions: Iron stores were not positively related to increased risk of ischemic stroke. Furthermore, HFE genotypes did not influence the risk of ischemic or hemorrhagic stroke. Copyright (c) 2007 S. Karger AG, Basel.
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| 2. |
- Ahmed, Istaq, 1972, et al.
(författare)
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Structural study and proton conductivity in Yb-doped BaZrO3
- 2007
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Ingår i: Solid State Ionics. - 0167-2738. ; 178:(7-10), s. 515-520
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Tidskriftsartikel (refereegranskat)abstract
- Traditional solid state sintering has been used to prepare the perovskite BaZr0.9Yb0.1O3-delta. Analysis of X-ray powder diffraction data shows that an increase of the unit cell parameter, a, was observed compared to undoped BaZrO3. Rietveld analysis of room temperature neutron powder diffraction data confirmed cubic symmetry (space group Pm-3m). Dynamic thermogravimetric analysis (TGA) indicates that the hydration process occurs below 200 degrees C. The strong O-H stretch band, 2500-3500 cm(-1), in the infrared absorbance spectrum clearly manifests the presence of protons in the hydrated material. Proton conductivity was investigated on hydrated and as-prepared samples under dry and wet atmospheres, respectively. Keywords: X-ray diffraction; neutron diffraction; Rietveld refinement; proton conductor; perovskite
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| 3. |
- Ahmed, Istaq, 1972, et al.
(författare)
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Synthesis and structural characterization of perovskite type proton conducting BaZr1-xInxO3-delta (0.0 <= x <= 0.75)
- 2006
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Ingår i: Solid State Ionics. - : Elsevier BV. - 0167-2738 .- 1872-7689. ; 177:17-18, s. 1395-1403
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Tidskriftsartikel (refereegranskat)abstract
- Solid state sintering has been used to prepare the cubic perovskite structured compounds BaZr1-xInxO3-delta (0.0 <= x <= 0.75). Analysis of X-ray powder diffraction (XRPD) data reveals that the unit cell parameter, a, increases linearly with an increased Indium concentration. XRPD data was also used to demonstrate the completion of sample hydration, which was reached when the materials showed a set of single-phase Bragg-peaks. Dynamic thermogravimetric analysis (TGA) data showed that approx. 89% of the total number of available oxygen vacancies can be filled in BaZr1-xInxO3-delta for x=0.50, and that the maximum water uptake occurs below 300 degrees C. Rietveld analysis of the room temperature neutron powder diffraction (NPD) data confirmed the average cubic symmetry (space group Pm-3m), and an expansion of the unit cell parameter after the hydration reaction. The strong O-H stretch band, 2500-3500 cm(-1), in the infrared absorbance spectrum clearly manifests the presence of protons in the hydrated material. Proton conductivity of hydrated BaZr1-xInxO3-delta, x=0.75 was investigated during heating and cooling cycles under dry argon atmosphere. The total conductivity during the heating cycle was nearly two orders of magnitude greater than that of cooling cycle at 300 degrees C, whilst these values were similar at higher temperatures i.e. T > 600 degrees C.
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| 4. |
- Davidsson, Kent, 1967, et al.
(författare)
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Potassium, chlorine, and sulfur in ash, particles, deposits, and corrosion during wood combustion in a circulating fluidized-bed boiler
- 2007
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Ingår i: Energy & Fuels. - : American Chemical Society (ACS). - 1520-5029 .- 0887-0624. ; 21:1, s. 71-81
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Tidskriftsartikel (refereegranskat)abstract
- The effect of the addition of chlorine and/or sulfur to the fuel on fly ash composition, deposit formation, and superheater corrosion has been studied during biomass combustion in a circulating fluidized-bed boiler. The chlorine (HCl (aq)) and sulfur (SO2 (g)) were added in proportions of relevance for the potassium chemistry. The composition of the bottom and the fly ashes was analyzed. Gas and particle measurements were performed downstream of the cyclone before the convection pass and the flue gas composition was recorded in the stack with a series of standard instruments and an FTIR analyzer. At the position downstream of the cyclone, a deposit probe was situated, simulating a superheater tube. Deposits on the probe and initial corrosion were examined. It is concluded that addition of sulfur and chlorine increases the formation of submicron particles leading to deposition of potassium sulfate and chloride. The results compare well with earlier work based on laboratory-scale experiments concerning effects of chlorine and sulfur on potassium chemistry.
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| 5. |
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| 6. |
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| 7. |
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| 8. |
- Johansson, Eva, et al.
(författare)
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Time, Symptom Burden, Androgen Deprivation, and Self-Assessed Quality of Life after Radical Prostatectomy or Watchful Waiting : The Randomized Scandinavian Prostate Cancer Group Study Number 4 (SPCG-4) Clinical Trial
- 2009
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Ingår i: European Urology. - : Elsevier. - 0302-2838 .- 1873-7560. ; 55:2, s. 422-432
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Quality-of-life outcomes are important in the choice of treatment strategy for men with localized prostate cancer.OBJECTIVE: To evaluate how follow-up time, number of physical symptoms, and presence of androgen deprivation affected quality of life among men randomized to radical prostatectomy or watchful waiting.DESIGN, SETTING, AND PARTICIPANTS: The study group was composed of all 376 living men included in the Swedish part of the Scandinavian Prostate Cancer Group Study Number 4 (SPCG-4) between January 1, 1989, and February 29, 1996. Quality-of-life data were collected after a mean follow-up time of 4.1 yr.INTERVENTION: All patients were randomly assigned to radical prostatectomy or watchful waiting. Forty-five men were androgen deprived.MEASUREMENTS: Data of specific symptoms, symptom-induced stress, sense of well-being, and self-assessed quality of life were obtained by means of a questionnaire. Psychological symptoms were assessed using seven-point visual digital scales.RESULTS AND LIMITATIONS: In analyses stratified on the basis of the numbers of physical symptoms, anxiety and depressed mood were less common, and sense of well-being and self-assessed quality of life were better throughout in the radical prostatectomy group than in the watchful waiting group. As the number of physical symptoms increased, all psychological variables became worse and more prominent in the watchful waiting group. After a follow-up time of 6-8 yr, a significant decrease in quality of life (p=0.03) was seen in the watchful waiting group. Twenty-four percent of androgen-deprived patients assigned to watchful waiting reported high self-assessed quality of life compared with 60% in the radical prostatectomy group. Eighty-eight percent of patients had clinically detected tumors.CONCLUSIONS: Androgen deprivation negatively affected self-assessed quality of life in men assigned to watchful waiting. The number of physical symptoms was associated with the level of quality of life. Quality of life was lower with longer follow-up time in both groups and was statistically significant in the watchful waiting group (p=0.03).
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| 9. |
- Johansson, Lars-Olof, 1957, et al.
(författare)
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Goal conflicts in political decision making: a survey of municipality politicians' view of road pricing.
- 2004
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Ingår i: Environment & Planning C: Government & Policy. - 0263-774X. ; 21:4, s. 615-624
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Tidskriftsartikel (refereegranskat)abstract
- Investigates the existence of goal conflicts in political decision-making in the case of municipality politicians in Sweden on the issue of road pricing scheme. Goals of municipality politicians other than reducing car use; Possibility of failure in achieving environmental goals because of goal conflicts.
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| 10. |
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| 11. |
- Niklasson, Annika, 1977, et al.
(författare)
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Air Pollutant Concentrations and Atmospheric Corrosion of Organ Pipes in European Church Environments
- 2008
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Ingår i: Studies in Conservation. - 0039-3630 .- 2047-0584. ; 53:1, s. 24-40
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Tidskriftsartikel (refereegranskat)abstract
- Abstract: The atmospheric environment inside and outside historical organs in several European regions is reported. In each region, comparisons were made between an instrument suffering organ pipe corrosion and an organ without corrosion problems. Concentrations of acetic acid (ethanoic acid), formic acid (methanoic acid), acetaldehyde (ethanal), formaldehyde (methanal) and other volatile organic compounds in the organ environment were determined using active sampling. Temperature and relative humidity were recorded. In addition, polished metal samples that mimic the material used in the historical organ pipes have been exposed in the organ wind systems for up to 22 months. High concentrations of acetic acid and formic acid vapours are present in the wind system of the corroded organs. Acetaldehyde and formaldehyde are also present in smaller amounts. The main source of acetic acid is the wood from which the wind system is built. In contrast, formic acid is generated in the chruch environment outside the wind system. The results show that the two organic acids play an important role in the atmospheric corrosion of organ pipes. It is suggested that the corrosion of lead pipes in historical organs can be effectively reduced by removing the sources of gaseous acetic acid and formic acid in the wind system and in the chruch environment.
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| 12. |
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| 13. |
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| 14. |
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| 15. |
- Albin, Maria, et al.
(författare)
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Cytogenetic and morphologic subgroups of myelodysplastic syndromes in relation to occupational and hobby exposures.
- 2003
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Ingår i: Scandinavian Journal of Work, Environment and Health. - 0355-3140. ; 29:5, s. 378-387
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVES: This study investigated the association between occupational and hobby exposure and the risk of myelodysplastic syndromes (MDS) while focusing on differential patterns of clonal chromosome aberrations and morphologic subgroups. METHODS: A case-referent study was conducted with 330 MDS patients investigated cytogenetically in 1976-1993 (cases) and matched referents. Telephone interviews with either the person or a next-of-kin were used. The participation rate of the cases and referents was 85% and 60%, respectively. Information was obtained from the next-of-kin more often for the cases (88%) than for the referents (26%). Occupational hygienists assessed the exposure using interview data on worktasks and hobbies. Associations with disease risk were evaluated for 10 exposures with a logistic regression analysis. RESULTS: The investigated exposures were generally not associated with cytogenetically abnormal MDS. Effect estimates for specific cytogenetic or morphologic subgroups were generally imprecise. Occupational exposure to extremely low-frequency magnetic fields (EMF) was associated with MDS with a normal karyotype [odds ratio (OR) 2.0, 95% confidence interval (95% CI) 1.0-4.0]. The exposure-response association was consistent for intensity but inconclusive for duration. A decreased risk was observed for MDS, irrespective of karyotypic pattern, among farmers and farmhands (OR 0.53, 95% CI 0.35-0.81). CONCLUSIONS: Cytogenetically abnormal MDS was generally not associated with occupational or hobby exposure to known or suspected genotoxic agents. However, exposure prevalences and intensities were low for several agents. An association was suggested between occupational exposure to EMF and MDS with a normal karyotype. Biases due to differential information quality and selective participation cannot be ruled out.
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| 16. |
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| 17. |
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| 18. |
- Andersson, Jonas, 1977-, et al.
(författare)
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C-reactive protein is a determinant of first-ever stroke: prospective nested case-referent study.
- 2009
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Ingår i: Cerebrovascular diseases (Basel, Switzerland). - : S. Karger AG. - 1421-9786 .- 1015-9770. ; 27:6, s. 544-51
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND AND PURPOSE: C-reactive protein (CRP) is a determinant of stroke, but there are no prospective studies on CRP and first ischemic stroke divided into etiologic subtypes. Our primary aim was to study CRP as a determinant of ischemic stroke, classified according to Trial of ORG 10172 in Acute Stroke Treatment (TOAST) criteria, and intracerebral hemorrhage (ICH) in a prospective study. A secondary aim was to study the relationship between the 1444C>T polymorphism, plasma levels of CRP and stroke. METHODS: The study was a prospective population-based case-referent study nested within the Northern Sweden Cohorts. We defined 308 cases of ischemic stroke and 61 ICH. Two controls for each case were defined from the same cohort. RESULTS: The OR for the highest (>3 mg/l) versus lowest group (<1 mg/l) of CRP was 2.58 (95% CI 1.74-3.84) for ischemic stroke and 1.63 (95% CI 0.67-3.93) for ICH. In a multivariate model including traditional risk factors, CRP remained associated with ischemic stroke (OR 2.06; 95% CI 1.29-3.29). Small-vessel disease was associated with CRP in the multivariate model (OR 3.88; 95% CI 1.10-13.7). The CRP 1444 (CC/CT vs. TT) polymorphism was associated with plasma levels of CRP but neither with ischemic stroke nor with ICH. CONCLUSIONS: This prospective population-based study shows that CRP is significantly associated with the risk of having a first ischemic stroke, especially for small-vessel disease. No significant associations were found between the CRP 1444C>T polymorphism and any stroke subtype.
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| 19. |
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| 20. |
- Asteman, Henrik, 1973, et al.
(författare)
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Effect of water-vapor-induced Cr vaporization on the oxidation of austenitic stainless steels at 700 and 900 degrees C - Influence of Cr/Fe ratio in alloy and Ce additions
- 2004
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Ingår i: Journal of the Electrochemical Society. - : The Electrochemical Society. - 1945-7111 .- 0013-4651. ; 151:3, s. B141-B150
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Tidskriftsartikel (refereegranskat)abstract
- The oxidation of 153MA, 310 and 353MA austenitic stainless steels was investigated at 700°C and 310 and 353MA at 900°C in O 2 and in O 2 + 40% H 2 O. 153MA was not studied at 900°C because it suffered excessive corrosion. The influence of gas velocity was studied. The oxidized samples were investigated by grazing angle X-ray diffraction, scanning electron microscopy/energy dispersive analysis by X-rays Auger-electron spectroscopy, and glow discharge optical emission spectroscopy. In the presence of water vapor, gas velocity strongly influenced oxidation. This effect is attributed to chromium evaporation in the form of CrO 2 (OH) 2 . Exposure in O 2 + 40% H 2 O at 700°C using high flow rates caused breakaway corrosion on all alloys. At 900°C, only the 310 and 353MA alloys were investigated. In O 2 + H 2 O environment, both alloys showed a mass loss at low flow rates due to chromium evaporation. At high flow rates, alloy 310 suffered breakaway corrosion while 353MA did not. The corrosion products consisted of a relatively thin Cr-rich (Cr,Fe) 2 O 3 oxide plus thick, iron-rich oxide islands. The greater corrosion resistance of 310 and 353MA steels in environments where chromium evaporation is a factor is attributed to the high Cr/Fe ratio. In contrast, the presence of Ce and Si in the MA grade steels appears to have little beneficial effect on breakaway corrosion triggered by Cr evaporation. © 2004 The Electrochemical Society. All rights reserved.
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| 21. |
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| 22. |
- Axelsson, Lars-Uno, 1979, et al.
(författare)
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Evaluation of the flow in an intermediate turbine duct at off-design conditions
- 2008
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Ingår i: ICAS 2008, 26th international congress of the aeronautical sciences, Alaska, August 2008. - 9781605607153 ; 2, s. 3286-3295
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Konferensbidrag (refereegranskat)abstract
- Intermediate turbine ducts are used in modern turbofan engines for connecting the highpressure turbine with the low-pressure turbine. The demands for engines with higher by-pass ratios require these ducts to be more "aggressive", i.e., to have a larger radial off-set and to be shorter. However, the flow in the intermediate turbine ducts are complex and therefore difficult to predict. Therefore a better understanding of the flow physics is necessary and measurements for CFD validation are needed. This paper presents time-averaged measurements of the flow in a state-at-the-art intermediate turbine duct with an upstream high-pressure turbine present. The investigation focuses on the intermediate turbine duct flow field development for different turbine conditions. The measurements consist of area traverses with a five-hole pressure probe at different axial locations within the intermediate turbine duct. In addition, a discussion of the endwall static pressure distribution and the overall pressure losses for the different conditions are done.
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| 23. |
- Axelsson, Lars-Uno, 1979, et al.
(författare)
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Experimental investigation of the time-averaged flow in an intermediate turbine duct
- 2008
-
Ingår i: GT2008-50829. Proceedings of ASME Turbo Expo 2008: Power for Land, Sea and Air, June 9-13, 2008, Berlin, Germany. - 9780791843161 ; 6:PART B
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Konferensbidrag (refereegranskat)abstract
- Intermediate turbine ducts are used in modern multi-spool jet engines to connect the high pressure turbine with the lowpressure turbine. The trend towards turbofan engines with larger by-pass ratios requires the radial off-set between the high-pressure and low-pressure turbines to increase with a corresponding increase in radial off-set for the intermediate turbine ducts. Other improvements of the ducts is to make them shorter and more diffusing but this strive towards more aggressive design increases the risk for separation. This paper deals with an experimental investigation of the time-averaged mean flow field and turbulence development in an aggressive intermediate turbine duct (downstream a rotating turbine stage) using a 5-hole probe and 2-component hot-wire anemometry. In addition the duct endwall static pressure distribution is discussed. The investigation revealed the complex flow structure development within the duct, where corotating vortices emanating from the break-up of the tip gap shear-layer dominates the flow pattern.
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| 24. |
- Axelsson, Lars-Uno, 1979, et al.
(författare)
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Fourier decomposed turbulence measurements downstream of a high-pressure turbine stage
- 2008
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Ingår i: 2008 ASME Fluids Engineering Division Summer Conference, FEDSM 2008; Jacksonville, FL; United States; 10 August 2008 through 14 August 2008. - 9780791848418 ; 2, s. 177-182
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Konferensbidrag (refereegranskat)abstract
- This forum paper discusses phase-resolved turbulence measurements of the flow downstream of an axial turbine, and especially how phase-resolved measurements compare to time-resolved measurements. The time-resolved spectra produced higher velocity fluctuations than the corresponding phase-resolved spectra even when the periodic component was filtered out from the time-resolved measurements. The phase-resolved spectrum effectively removes all the peaks in the spectrum except for the ones associated with the blade-passage frequency.
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| 25. |
- Bengtsson-Blücher, Daniel, et al.
(författare)
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Influence of ppb levels of SO2 on the atmospheric corrosion of aluminum in the presence of NaCl
- 2005
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Ingår i: Journal of the Electrochemical Society. - 1945-7111 .- 0013-4651. ; 152(10), s. B397-B404
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Tidskriftsartikel (refereegranskat)abstract
- The effect of part per billion (ppb) levels of SO2 on the atmospheric corrosion on Al (99.999%) was investigated in the laboratory at 22 degrees C. Exposure time was 20 and 672 h. The effect of SO2 concentration (46-1300 ppb), relative humidity (70- 99% RH), and the amount of NaCl applied prior to exposure (0- 250 mu g/cm(2)) was studied. In addition, the effect of O-3 and NO2 on the SO2 deposition rate was addressed. The samples were investigated by gravimetry, grazing incidence X-ray powder diffraction, ion chromatography, optical microscopy, and environmental scanning electron microscopy equipped with energy-dispersive X-ray fluorescence. SO2 accelerates the atmospheric corrosion of Al, forming corrosion product "islands" containing aluminum hydroxy sulfate. Combining NaCl and SO2 has a synergistic effect on the average corrosion rate. In contrast, the chloride-induced pitting of aluminum is significantly reduced by SO2. The corrosivity of SO2 is attributed to the acidification of the surface electrolyte that destabilizes the alumina passive film. The suppression of pitting corrosion by SO2 is attributed to the formation of aluminum hydroxy sulfates that are less soluble than the corresponding chlorides and slows down pit propagation. At relative humidities above 70% RH, there is a measurable steady-state deposition of SO2 that corresponds to the rate of formation of sulfate. The SO2 deposition rate is not limited by the oxidation of (IV)-valent sulfur on the surface. SO2 deposition is enhanced by sodium chloride because the corrosion reactions in the NaCl(aq) electrolyte result in high pH in the cathodic regions and the formation of aluminum hydroxide. Ozone in the ppb range has only transient effects on the SO2 deposition rate, whereas ppb levels of NO2 had no effect at (c) 2005 The Electrochemical Society.
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| 26. |
- Blomgren, Lena, 1957-
(författare)
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Varicose Veins : Aspects on Diagnosis and Surgical Treatment
- 2005
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Treatment for varicose veins (VV) is insufficiently evidence based and recurrence rates are high. The aim of this thesis was to study the long-term results after VV surgery, risk factors for recurrences and the effect of preoperative duplex scanning on recurrence rate, quality of life (QoL) and costs.In a follow-up study 89 patients with 100 legs operated on for VV 6–10 years earlier were re-examined with duplex, in 13 cases also with varicography. 57% had incompetent vessels in the groin visible with duplex, equally well defined by varicography. Residual branches could not be differentiated from new vessel formation. The recurrence rate did not correlate to the surgeon’s level of experience or perioperative difficulties at primary surgery. In a prospective randomized study 293 patients (343 legs) were operated on for primary VV with or without preoperative duplex. Duplex was done postoperatively, at 2 months and 2 years. QoL was measured with SF-36 preoperatively, at 1 month, 1 year and 2 years. After 2 years the number of reoperations were 2 in the group with preoperative duplex and 14 in the group without (p=0.002). Incompetent veins were seen in the saphenofemoral or saphenopopliteal junction in 19 and 53 legs respectively (p<0.001).Preoperative QoL was worse in the VV patients compared to a reference population, and was normalised 2 years postoperatively. The improved surgical result in the duplex group was not reflected in a significantly higher QoL. The lower costs for redo surgery in the duplex group did not offset the costs for duplex, partly due to more extensive primary surgery. A significant proportion of recurrences after 2 years was new vessel formation and progression of disease. Preoperative perforating vein incompetence did not influence recurrence rate, and was abolished without specific interruption in 60% at 2 years postoperatively.
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| 27. |
- Blücher, D. Bengtsson, et al.
(författare)
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Scanning kelvin probe force microscopy - A useful tool for studying atmospheric corrosion of MgAl alloys in situ
- 2004
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Ingår i: JOURNAL OF THE ELECTROCHEMICAL SOCIETY. - : The Electrochemical Society. - 0013-4651 .- 1945-7111. ; 151:12
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Tidskriftsartikel (refereegranskat)abstract
- Scanning Kelvin probe force microscopy (SKPFM) is used to study the initial stages of atmospheric corrosion of an AlMg alloy and of physical vapor deposition (PVD) deposited 2 μm Al dots on pure Mg. The latter system is used as a model of a two-phase AlMg alloy. The influence of CO2 was studied in situ in humid air using SKPFM. This method allows for the in situ investigation of the evolution of the Volta potential during exposure, the resolution being in the submicrometer range. The temperature was 22.0°C, and the relative humidity was 85 or 95%. The concentration of CO2 was <1 or 350 ppm. The corrosion products were analyzed by gravimetry, ion chromatography, X-ray diffraction, scanning electron microscopy, scanning Kelvin probe, and Auger electron spectroscopy. We found that the initial stages of atmospheric corrosion on magnesium are influenced by the presence of cathodic PVD-deposited aluminum. A similar effect was seen in the case of AZ91D, the aluminum-rich β-phase forming the cathodic areas. The β-phase is nobler compared to the substrate because of the higher Al content. In the absence of CO2, the corrosion attack is localized in nature whereas the presence of ambient levels of CO2 results in a more general corrosion attack. The inhibitive effect of CO2 on the atmospheric corrosion of AZ91D is explained by the formation of a passivating layer of Mg5(CO3)4(OH)2⋅5H2O. In the absence of CO2, the increase in pH originating from the cathodic reaction results in the dissolution of aluminum in the passive layer. A corrosion mechanism is proposed explaining the behavior in the two environments.
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| 28. |
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| 29. |
- Broliden, Per Anders, et al.
(författare)
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Antithymocyte globulin and cyclosporine A as combination therapy for low-risk non-sideroblastic myelodysplastic syndromes
- 2006
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Ingår i: Haematologica. - 0390-6078 .- 1592-8721. ; 91:5, s. 667-670
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Tidskriftsartikel (refereegranskat)abstract
- The present study evaluated the combination of antithymocyte globulin (ATG) and cyclosporine A (CsA) in patients with low-risk myelodysplastic syndromes. Twenty patients (17 with refractory anemia and 3 with refractory anemia with excess blasts) received treatment with rabbit-ATG plus CsA. The overall response rate was 30% (6/20); three of the six responders had a complete response. The responses lasted 2-58 months, with two patients still being in complete remission at 42 and 58 months. Short-lasting cytogenetic remissions were achieved in two patients. ATG was poorly tolerated in patients over 70 years of age. Four out of 20 patients progressed to acute myeloid leukemia within a year. We conclude that immunosuppressive treatment may be a therapeutic option for selected patients with myelodysplastic syndrome.
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| 30. |
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| 31. |
- Castor, Anders, et al.
(författare)
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Distinct patterns of hematopoietic stem cell involvement in acute lymphoblastic leukemia
- 2005
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Ingår i: Nature Medicine. - : Springer Science and Business Media LLC. - 1078-8956 .- 1546-170X. ; 11:6, s. 630-637
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Tidskriftsartikel (refereegranskat)abstract
- The cellular targets of primary mutations and malignant transformation remain elusive in most cancers. Here, we show that clinically and genetically different subtypes of acute lymphoblastic leukemia (ALL) originate and transform at distinct stages of hematopoietic development. Primary ETV6-RUNX1 (also known as TEL-AML1) fusions and subsequent leukemic transformations were targeted to committed B-cell progenitors. Major breakpoint BCR-ABL1 fusions (encoding P210 BCR-ABL1) originated in hematopoietic stem cells (HSCs), whereas minor BCR-ABL1 fusions (encoding P190 BCR-ABL1) had a B-cell progenitor origin, suggesting that P190 and P210 BCR-ABL1 ALLs represent largely distinct tumor biological and clinical entities. The transformed leukemia-initiating stem cells in both P190 and P210 BCR-ABL1 ALLs had, as in ETV6-RUNX1 ALLs, a committed B progenitor phenotype. In all patients, normal and leukemic repopulating stem cells could successfully be separated prospectively, and notably, the size of the normal HSC compartment in ETV6-RUNX1 and P190 BCR-ABL1 ALLs was found to be unaffected by the expansive leukemic stem cell population.
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| 32. |
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| 33. |
- Chen, HonQui, et al.
(författare)
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Determining the crystal symmetry of epitaxial Tl-2201 thin films by X-ray diffraction
- 2002
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Ingår i: Physica. C, Superconductivity. - 0921-4534. ; 371:2, s. 83-89
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Tidskriftsartikel (refereegranskat)abstract
- The crystal symmetry of epitaxial Tl-2201 films on LaAlO3 and SrTiO3 substrates is investigated by X-ray diffraction. In the case of Tl1.85Ba2CuO6 film, a φ-scan of the (1 1 10) reflection showed four diffraction peaks separated by 90.00±0.02°. A 2θ-scan of the same reflection exhibited a single peak. 2Θ−ω- and φ-scans of the corresponding reflection in Tl2.04Ba2CuO6 show splitting and broadening of the diffraction peaks indicating an orthorhombic distortion. The effect of errors in film alignment on the φ-scan and 2Θ−ω-scans is discussed. A periodic function, δ=a+bsin(ω−φ), was used to correct the φ-scan measurements. The influence of lattice mismatch between film and substrate on the structural symmetry of the films is discussed.
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| 34. |
- Chen, H.Q., et al.
(författare)
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Critical behavior of vortices in epitaxial Tl-2201 films at zero external field
- 2004
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Ingår i: PHYSICA STATUS SOLIDI B-BASIC RESEARCH. - : Wiley. - 0370-1972 .- 1521-3951. ; 241:15, s. 3556-3562
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Tidskriftsartikel (refereegranskat)abstract
- The resistive transition and current–voltage characteristics of a Tl-2201 superconducting microbridge are measured close to the critical temperature in zero external magnetic field. The dissipation mechanism is studied by analyzing dV/dI and power dissipation P(= IV) as functions of transport current. The Jc–T curves exhibit three distinct types of behavior depending on temperature. In the low temperature regime, the critical current density is proportional to (1 – T/Tc). At intermediate temperatures, thermally activated flux creep dominates and Jc is proportional to 1 – n(T/Tc) – m(T/Tc)2. In the high temperature regime, Jc is equal to the G–L depairing current. The depinning current, Jc1, is determined, taking into account thermally activated flux motion and flux motion induced by the transport current. Jc1 depends linearly on temperature and vanishes at 82 K, Jc1 = Jc1(0) (1 – T/Tc1).
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| 35. |
- Chiavari, C, et al.
(författare)
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Atmospheric corrosion of historical organ pipes: The influence of environment and materials
- 2008
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Ingår i: Corrosion Science. - : Elsevier BV. - 0010-938X. ; 50:9, s. 2444-2455
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Tidskriftsartikel (refereegranskat)abstract
- The corrosion of lead-rich pipes in historical organs in different parts of Europe has been investigated. The influence of the environment and the composition and microstructure of the pipe metal was studied. Pipe Corrosion was documented by visual inspection (boroscope). The corrosion attack and the composition and microstructure of the metal were characterized by OM, SEM, XRD, IC and FAAS. It is shown that the degree of corrosion of the pipes is correlated to the concentration of gaseous acetic and formic acid in the organ. The organic acids are emitted by the wood from which the wind system is built. It is also shown that pipe corrosion decreases with increasing tin content in the range 0-4% (wt). Possible conservation strategies are discussed. (c) 2008 Elsevier Ltd. All rights reserved.
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| 36. |
- Chiragwandi, Zackary, 1968, et al.
(författare)
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Properties of a bio-photovoltaic nano-device
- 2008
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Ingår i: Journal of Physical Chemistry C. - : American Chemical Society (ACS). - 1932-7447 .- 1932-7455. ; 112:48, s. 18717-18721
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Tidskriftsartikel (refereegranskat)abstract
- Properties of an on-chip photovoltaic nanodevice are demonstrated. The dyes comprise green florescent proteins(GFP). Dependence of recently reported zero external potential bias (ZEPB) photocurrent (I) on temperature,power, and wavelength (λ) is shown. Correlation between UV-vis spectrum of the GFP and the ZEPB I(λ)of the device is reported. The temperature dependence suggests the ZEPB photocurrent to reflect a liquidcrystal type ordering where the current declines monotonically with increasing temperature. The influence ofan external bias on the photocurrent is demonstrated. The resulting light-induced current is analyzed in termsof resistive and quantum mechanical contributions.
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| 37. |
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| 38. |
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| 39. |
- Engkvist, Josefin, 1972, et al.
(författare)
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Oxidation of FeCrAl foils at 500-900 degrees C in dry O-2 and O-2 with 40% H2O
- 2009
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Ingår i: Materials at High Temperatures. - 0960-3409 .- 1878-6413. ; 26:2, s. 199-210
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Tidskriftsartikel (refereegranskat)abstract
- High temperature resistant FeCrAl alloys are frequently used in high temperature applications Such as heating elements and metal based catalytic converter bodies. When exposed to high temperatures an adherent, slowly growing, dense aluminium oxide layer forms on the surface, which protects the underlying alloy from severe degradation. The composition, structure and properties of the formed oxide layer are strongly dependent on the alloy composition, temperature and oxidation environment. In this study, the Sandvik 0C404 FeCrAl alloy, in the form of 50 mu m thick foils, was exposed isothermally in the temperature range 500-900 degrees C for 168 hours in dry O-2 and in O-2 with 40 vol.% H2O. The surface morphology, composition and microstructure of the grown oxide scales were characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDX), grazing incidence X-ray diffraction (GI-XRD), Auger electron spectroscopy (AES), and time of flight secondary ion mass spectrometry (TOF-SIMS). The oxidation process was faster at 900 degrees C than at 500 and 700 degrees C. At 500 degrees C a thin (10-20 nm) mixed oxide of Fe, Cr and Al was formed. Exposure at 700 degrees C resulted ill a similar (40-50 nm) duplex oxide, in both dry O-2 and in O-2 With 40 vol.% H2O. These oxide scales consisted of all inner and an outer relatively pure alumina separated by a Cr-rich band. This type of duplex oxide scale also formed at 900 degrees C with a thin inward growing alpha-Al2O3 at the oxide/metal interface and an outward growing layer outside a Cr-rich band. However, at 900 degrees C the Outward growing layer showed two types of oxide morphologies; a thin smooth base oxide and a much thicker nodular oxide grown on top of substrate ridges. In dry O-2 atmosphere, the main part of this outward growing layer had transformed to alpha-Al2O3. Only in the outer part of the thick oxide nodules, metastable alumina was found. When exposed in the presence of water vapour the main pall of the metastable alumina remained untransformed.
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| 40. |
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| 41. |
- Folkeson, Nicklas, 1981, et al.
(författare)
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Fireside corrosion of stainless and low alloyed steels in a waste-fired CFB boiler; The effect of adding sulphur to the fuel
- 2008
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Ingår i: Materials Science Forum. ; 595-598, s. 289-297
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Tidskriftsartikel (refereegranskat)abstract
- Corrosion field tests have been carried out in the superheater region of a commercial waste-fired 75MW CFBC boiler using air cooled probes. Exposure time was 24 and 1000 hours. The effect of adding sulphur to the fuel on the corrosion of two high alloyed steels and a low alloyed steel was studied. The fuel consisted of 50% household waste and 50% industrial waste. The exposed samples were analyzed by ESEM/EDX and XRD. Metal loss was determined after 1000 hours. Both materials suffered significant corrosion in the absence of sulphur addition and the addition of sulphur to the fuel reduced corrosion significantly. The rapid corrosion of the high alloyed steel in the absence of sulphur addition is caused by the destruction of the chromium-containing protective oxide by formation of calcium chromate. Adding sulphur to the fuel inhibited chromate formation and increased the sulphate/chloride ratio in the deposit. Iron(II) chloride formed on the low alloyed steel regardless of whether sulphur was added or not.
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| 42. |
- Folkeson, Nicklas, 1981, et al.
(författare)
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Initial stages of the HCl-induced high-temperature corrosion of alloy 310
- 2007
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Ingår i: Journal of the Electrochemical Society. - 1945-7111 .- 0013-4651. ; , s. 515-521
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Tidskriftsartikel (refereegranskat)abstract
- Polished 310 stainless steel coupons were exposed isothermally in a horizontal tube furnace at 500 C for 1-168 h. The exposure gas consisted of N-2 with 5% O-2 and 500 ppm HCl(g). The corroded samples were analyzed by X-ray diffraction, focused ion beam microanalysis, scanning electron microscopy with energy-dispersive X-ray analysis, and by Auger electron spectroscopy. Mass gain was recorded. As expected, HCl (g) is a corrosion accelerator, the dominating corrosion products being FeCl2, Fe2O3, and Cr2O3. A tentative mechanism for the initial stages of the HCl-induced corrosion of stainless steel is presented. (c) 2007 The Electrochemical Society.
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| 43. |
- Froitzheim, Jan, 1981, et al.
(författare)
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Chromium evaporation of Coated and uncoated FE-22CR steels investigated by a novel denuder technique
- 2009
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Ingår i: 3rd European Fuel Cell Technology and Applications - Piero Lunghi Conference, EFC 2009; Rome; Italy; 15 December 2009 through 18 December 2009. - 9788882862114 ; , s. 77-78
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Konferensbidrag (refereegranskat)abstract
- The formation of volatile chromium species is a major problem concerning metallic interconnects for Solid Oxide Fuel Cells (SOFC). This problem is known and a number of routes, usually in the form of coatings, has been presented to overcome this problem. This paper investigates the influence of thin metallic films which can be applied by a low cost process. The measurements are carried out by a novel denuder technique where volatile chromium species are collected as sodium chromate. This technique allows the quantification of chromium evaporation in a time resolved manner. Coated and uncoated samples of ferritic steels developed for SOFC applications are investigated at 850°C in a N2-O2-H2O environment.
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| 44. |
- Froitzheim, Jan, 1981, et al.
(författare)
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Cr evaporation of metallic interconnects: A novel method for quantification
- 2009
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Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. - 9781566777391 ; 25:2 PART 2, s. 1423-1428
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Konferensbidrag (refereegranskat)abstract
- Chromium evaporation from metallic interconnects in SOFCs is commonly poisoning the cathode of SOFCs. To reduce chromium evaporation, rather thick coatings have been deposited using various coating techniques. In this study, a 22% Cr ferritic steel has been coated with thin films (
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| 45. |
- Götlind, Helena, 1978, et al.
(författare)
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The effect of water vapor on the initial stages of oxidation of the FeCrAl alloy Kanthal AF at 900 degrees C
- 2007
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Ingår i: Oxidation of Metals. - 1573-4889 .- 0030-770X. ; , s. 251-266
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Tidskriftsartikel (refereegranskat)abstract
- The effect of water vapor on the initial stages of oxidation of the FeCrAl alloy Kanthal AF is reported. Polished samples were exposed isothermally at 900 degrees C for 1, 24, 72 and 168 h in a well-controlled environment consisting of dry O-2 or O-2 + 40% H2O. The samples were investigated using a combination of gravimetry and several surface-analytical techniques, including XRD, SEM, EDX, FIB, AES and TEM. The presence of water vapor significantly accelerates oxidation during the first 72 h. A two-layered oxide forms in both the dry and wet environments. The bottom layer consists of inward-growing alpha-Al2O3 while the outer layer initially consists of outward-growing gamma-Al2O3. A straight and narrow Cr-enriched band is present at the top of the lower (alpha-Al2O3) oxide, corresponding to the original sample surface. In dry O-2, the top (gamma-Al2O3) layer is converted into a mixture of gamma-Al2-x (Mg,Fe) (x) O-3-(x/2),O- MgAl2O4 and alpha-Al2O3. This transformation does not occur in O-2 + H2O. The initial acceleration of oxidation by H2O is attributed to the stabilization of the outward-growing gamma-alumina layer by the hydroxylation of the gamma-Al2O3 surface. A schematic mechanism of the early stages of oxidation of FeCrAl alloys is presented, emphasizing the influence of water vapor.
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| 46. |
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| 47. |
- Hagfors, Linda, et al.
(författare)
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Antioxidant intake, plasma antioxidants and oxidative stress in a randomized, controlled, parallel, Mediterranean dietary intervention study on patients with rheumatoid arthritis
- 2003
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Ingår i: Nutrition Journal. - : Springer Science and Business Media LLC. - 1475-2891. ; 2
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Background: Previously we have reported that patients with rheumatoid arthritis (RA) obtained a significant reduction in disease activity by adopting a Mediterranean-type diet. The present study was carried out to investigate the antioxidant intake, the plasma levels of antioxidants and a marker of oxidative stress (malondialdehyde) during the study presented earlier. Methods: RA patients randomized to either a Mediterranean type diet (MD group, n = 26) or a control diet (CD group, n = 25) were compared during a three month dietary intervention study. Their antioxidant intake was assessed by means of diet history interviews and their intake of antioxidant-rich foods by a self-administered questionnaire. The plasma levels of retinol, antioxidants (a- and ?-tocopherol, ▀-carotene, lycopene, vitamin C and uric acid) and urinary malondialdehyde (MDA), a marker for oxidative stress, were determined using high performance liquid chromatography. The Student's t-test for independent samples and paired samples were used to test differences between and within groups. For variables with skewed distributions Mann-Whitney U-test and Wilcoxon signed ranks test were performed. To evaluate associations between dietary intake of antioxidants, as well as between disease activity, MDA and antioxidants we used Pearson's product moment correlation or Spearman's rank correlation. Results: The MD group had significantly higher intake frequencies of antioxidant-rich foods, and also higher intakes of vitamin C (p = 0.014), vitamin E (p = 0.007) and selenium (p = 0.004), and a lower intake of retinol (p = 0.049), compared to the CD group. However, the difference between the groups regarding vitamin C intake was not significant when under- and over-repoters were excluded (p = 0.066). There were no changes in urine MDA or in the plasma levels of antioxidants (after p-lipid adjustments of the tocopherol results), from baseline to the end of the study. The levels of retinol, vitamin C and uric acid were negatively correlated to disease activity variables. No correlation was found between antioxidant intake and the plasma levels of antioxidants. Conclusions: Despite an increase in reported consumption of antioxidant-rich foods during the Mediterranean diet intervention, the levels of plasma antioxidants and urine MDA did not change. However, the plasma levels of vitamin C, retinol and uric acid were inversely correlated to variables related to RA disease activity.
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| 48. |
- Hagfors, Linda, 1974-, et al.
(författare)
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Antioxidant intake, plasma antioxidants and oxidative stress in a randomized, controlled, parallel, Mediterranean dietary intervention study on patients with rheumatoid arthritis
- 2003
-
Ingår i: Nutrition Journal. - : Springer Science and Business Media LLC. - 1475-2891. ; 2:5
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Previously we have reported that patients with rheumatoid arthritis (RA) obtained a significant reduction in disease activity by adopting a Mediterranean-type diet. The present study was carried out to investigate the antioxidant intake, the plasma levels of antioxidants and a marker of oxidative stress (malondialdehyde) during the study presented earlier. Methods: RA patients randomized to either a Mediterranean type diet (MD group; n = 26) or a control diet (CD group; n = 25) were compared during a three month dietary intervention study. Their antioxidant intake was assessed by means of diet history interviews and their intake of antioxidant-rich foods by a self-administered questionnaire. The plasma levels of retinol, antioxidants (α- and γ-tocopherol, β-carotene, lycopene, vitamin C and uric acid) and urinary malondialdehyde (MDA), a marker for oxidative stress, were determined using high performance liquid chromatography. The Student's t-test for independent samples and paired samples were used to test differences between and within groups. For variables with skewed distributions Mann-Whitney U-test and Wilcoxon signed ranks test were performed. To evaluate associations between dietary intake of antioxidants, as well as between disease activity, MDA and antioxidants we used Pearson's product moment correlation or Spearman's rank correlation. Results: The MD group had significantly higher intake frequencies of antioxidant-rich foods, and also higher intakes of vitamin C (p = 0.014), vitamin E (p = 0.007) and selenium (p = 0.004), and a lower intake of retinol (p = 0.049), compared to the CD group. However, the difference between the groups regarding vitamin C intake was not significant when under- and over-repoters were excluded (p = 0.066). There were no changes in urine MDA or in the plasma levels of antioxidants (after p-lipid adjustments of the tocopherol results), from baseline to the end of the study. The levels of retinol, vitamin C and uric acid were negatively correlated to disease activity variables. No correlation was found between antioxidant intake and the plasma levels of antioxidants. Conclusions: Despite an increase in reported consumption of antioxidant-rich foods during the Mediterranean diet intervention, the levels of plasma antioxidants and urine MDA did not change. However, the plasma levels of vitamin C, retinol and uric acid were inversely correlated to variables related to RA disease activity.
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| 49. |
- Hagfors, Linda, et al.
(författare)
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Fat intake and composition of fatty acids in serum phospholipids in a randomized, controlled, Mediterranean dietary intervention study on patients with rheumatoid arthritis
- 2005
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Ingår i: Nutrition & Metabolism. - London : BioMed Central (BMC). - 1743-7075. ; 2:Article number 26
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: We have previously reported that rheumatoid arthritis patients, who adopted a modified Cretan Mediterranean diet, obtained a reduction in disease activity and an improvement in physical function and vitality. This shift in diet is likely to result in an altered intake of fatty acids. Therefore, the objective of the present study was to examine the dietary intake of fatty acids, as well as the fatty acid profile in serum phospholipids, during the dietary intervention study presented earlier. RESULTS: From baseline to the end of the study, changes in the reported consumption of various food groups were observed in the Mediterranean diet group. The change in diet resulted in a number of differences between the Mediterranean diet group and the control diet group regarding the fatty acid intake. For instance, a lower ratio of n-6 to n-3 fatty acids was observed in the Mediterranean diet group, both assessed by diet history interviews (dietary intake) and measured in serum phospholipids. Moreover, the patients in the Mediterranean diet group that showed a moderate or better clinical improvement during the study (diet responders), had a higher reported intake of n-3 fatty acids and a lower ratio of n-6 to n-3 fatty acids compared to the patients with minor or no improvement. Also the fatty acid profile in serum phospholipids differed in part between the diet responders and the diet non-responders. CONCLUSION: The changes in the fatty acid profile, indicated both by dietary assessments and through fatty acids in s-phospholipids may, at least in part, explain the beneficial effects of the Cretan Mediterranean diet that we have presented earlier.
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| 50. |
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