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1.	Zamora, Juan Carlos, et al. (författare) Considerations and consequences of allowing DNA sequence data as types of fungal taxa 2018 Ingår i: IMA Fungus. - : INT MYCOLOGICAL ASSOC. - 2210-6340 .- 2210-6359. ; 9:1, s. 167-185 Tidskriftsartikel (refereegranskat)abstract Nomenclatural type definitions are one of the most important concepts in biological nomenclature. Being physical objects that can be re-studied by other researchers, types permanently link taxonomy (an artificial agreement to classify biological diversity) with nomenclature (an artificial agreement to name biological diversity). Two proposals to amend the International Code of Nomenclature for algae, fungi, and plants (ICN), allowing DNA sequences alone (of any region and extent) to serve as types of taxon names for voucherless fungi (mainly putative taxa from environmental DNA sequences), have been submitted to be voted on at the 11th International Mycological Congress (Puerto Rico, July 2018). We consider various genetic processes affecting the distribution of alleles among taxa and find that alleles may not consistently and uniquely represent the species within which they are contained. Should the proposals be accepted, the meaning of nomenclatural types would change in a fundamental way from physical objects as sources of data to the data themselves. Such changes are conducive to irreproducible science, the potential typification on artefactual data, and massive creation of names with low information content, ultimately causing nomenclatural instability and unnecessary work for future researchers that would stall future explorations of fungal diversity. We conclude that the acceptance of DNA sequences alone as types of names of taxa, under the terms used in the current proposals, is unnecessary and would not solve the problem of naming putative taxa known only from DNA sequences in a scientifically defensible way. As an alternative, we highlight the use of formulas for naming putative taxa (candidate taxa) that do not require any modification of the ICN.
2.	Alnegren, Patrik, 1988, et al. (författare) Inhibiting chromium evaporation and oxide scale growth on SOFC metallic interconnects by nano coatings 2014 Ingår i: 20th World Hydrogen Energy Conference, WHEC 2014. - 9780000000002 ; 1:2014 Konferensbidrag (refereegranskat)abstract High chromium ferritic steel is today the most commonly considered material for SOFC interconnectors due to many desirable properties, such as matching thermal expansion coefficient with other cell components but most importantly better machinability and price compared to ceramic alternatives. Yet there are some obstacles that need to be addressed before long term stability of a ferritic steel interconnector based fuel cell stack can be realized. First of all the electrical conductivity needs to remain high throughout the fuel cell stack operating life time and thus the formed oxide layers need to be electrically conductive and thin. Secondly, volatilization of chromium from the oxide scale of metallic interconnects causes rapid degradation due cathode poisoning. In the current study both oxidation and chromium evaporation of ferritic steel substrates are investigated in controlled atmospheres that simulates the environments of an operating SOFC stack. Samples coated with nanometer scale dual coatings of Co and Ce were tested. The dual coating substantially increased the performance of the ferritic substrates by i) significantly reducing oxidation rate, ii) increasing scale adherence and iii) diminishing chromium evaporation by 90 % via the formation of a Co-Mn-spinel cap layer.
3.	Grolig, Jan Gustav, 1986, et al. (författare) Coated stainless steel 441 as interconnect material for solid oxide fuel cells: Evolution of electrical properties 2015 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 284, s. 321-327 Tidskriftsartikel (refereegranskat)abstract AISI 441 coated. with a double layer coating of 10 nm cerium (inner layer) and 630 nm cobalt was investigated and in addition the uncoated material was exposed for comparison. The main purpose of this investigation was the development of a suitable ASR characterization method. The material was exposed to a simulated cathode atmosphere of air with 3% water at 850 degrees C and the samples were exposed for up to 1500 h. We compared two methods of ASR measurements, an in-situ method where samples were measured with platinum electrodes for longer exposure times and an ex-situ method where pre-oxidized samples were measured for only very short measurement times. It was found that the ASR of ex-situ characterized samples could be linked to the mass gain and the electrical properties could be linked to the evolving microstructure during the different stages of exposure. Both the degradation of the electric performance and the oxygen uptake (mass gain) followed similar trends. After about 1500 h of exposure an ASR value of about 15 m Omega cm(2) was reached. The in-situ measured samples suffered from severe corrosion attack during measurement. After only 500 h of exposure already a value of 35 m Omega cm(2) was obtained.
4.	Grolig, Jan Gustav, 1986, et al. (författare) Coated stainless steel 441 as interconnect material for solid oxide fuel cells: Oxidation performance and chromium evaporation 2014 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 248, s. 1007-1013 Tidskriftsartikel (refereegranskat)abstract Reactive Element (RE) and RE/cobalt-coated stainless steel AISI 441 was exposed at Solid Oxide Fuel Cell (SOFC) cathode conditions (850 degrees C in air with 3% water content) for up to 500 h. The chromium evaporation was measured by applying the denuder technique. Uncoated material exhibited severe spallation which could be successfully prevented by using cerium or lanthanum coatings. By applying double layer coatings of cerium or lanthanum in combination with cobalt the oxidation rate was decreased and the chromium volatilisation was also about 90% lower than the uncoated material.
5.	Grolig, Jan Gustav, 1986, et al. (författare) Copper based conversion coatings on ferritic stainless strip steel as solid oxide fuel cell interconnects: Oxidation performance and chromium evaporation 2013 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. ; 57:1, s. 2339-2347 Konferensbidrag (refereegranskat)abstract Ferritic stainless steels such as Crofer 22 H or Sanergy HT have been proven to be effective interconnect materials when additionally coated. These coatings, mainly based on cobalt spinels, successfully prevent chromium evaporation and are stable for long exposure times. A new approach is using copper based spinel coatings which are promising concerning price, conductivity and stability. This investigation is dedicated to a selection of copper spinel conversion coatings, their stability and ability to prevent chromium evaporation. Chromium release was monitored in humidified air (at 850 °C) using the denuder technique. The coatings were post analysed utilizing electron microscopy.
6.	Grolig, Jan Gustav, 1986, et al. (författare) Copper Iron Conversion Coating for Solid Oxide Fuel Cell Interconnects 2015 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 297, s. 534-539 Tidskriftsartikel (refereegranskat)abstract A conversion coating of iron and copper was investigated with the purpose of increasing the performance of Sanergy HT as a potential SOFC interconnect material. Samples were exposed to a simulated cathode atmosphere (air, 3 % H2O) for durations of up to 1000 h at 850 °C. Their performance in terms of corrosion, chromium evaporation and electrical resistance (ASR) was monitored and compared to uncoated and cobalt-coated Sanergy HT samples. The copper iron coating had no negative effects on corrosion protection and decreased chromium evaporation by about 80%. An Area Specific Resistance (ASR) of 10 mΩcm2 was reached after 1000 h of exposure. Scanning Electron Microscopy revealed well adherent oxide layers comprised of an inner chromia layer and an outer spinel oxide layer.
7.	Grolig, Jan Gustav, 1986, et al. (författare) Effect of Cerium on the Electrical Properties of a Cobalt Conversion Coating for Solid Oxide Fuel Cell Interconnects - A Study Using Impedance Spectroscopy 2015 Ingår i: Electrochimica Acta. - : Elsevier BV. - 0013-4686. ; 184, s. 301-307 Tidskriftsartikel (refereegranskat)abstract Coatings of metallic cobalt, which convert into a cobalt manganese spinel oxide are known to improve the properties of interconnects for solid oxide fuel cells (SOFCs). The addition of cerium to the cobalt coating further improves the corrosion properties of the material. For this study traditional four-point DC measurements at high temperatures were combined with impedance spectroscopy at low temperatures in order to investigate the effect of cerium on the electrical properties of a cobalt conversion coating. It was found that combination-coatings of cerium and cobalt exhibit superior electrical properties compared to pure cobalt coatings. Cerium slows down the growth of chromia and prevents the outward diffusion of iron into the cobalt spinel layer. Both effects are beneficial for the electrical properties of the interconnect. Impedance spectroscopy measurements revealed that even after more than 3000 h of exposure the outer cobalt manganese spinel layer still has a higher electrical conductivity when cerium was present.
8.	Alehagen, Urban, et al. (författare) Less fibrosis in elderly subjects supplemented with selenium and coenzyme Q10-A mechanism behind reduced cardiovascular mortality? 2018 Ingår i: Biofactors. - : John Wiley & Sons. - 0951-6433 .- 1872-8081. ; 44:2, s. 137-147 Tidskriftsartikel (refereegranskat)abstract BACKGROUND: In an intervention study where 221 healthy elderly persons received selenium and coenzyme Q10 as a dietary supplement, and 222 received placebo for 4 years we observed improved cardiac function and reduced cardiovascular mortality. As fibrosis is central in the aging process, we investigated the effect of the intervention on biomarkers of fibrogenic activity in a subanalysis of this intervention study.MATERIAL AND METHODS: In the present subanalysis 122 actively treated individuals and 101 controls, the effect of the treatment on eight biomarkers of fibrogenic activity were assessed. These biomarkers were: Cathepsin S, Endostatin, Galectin 3, Growth Differentiation Factor-15 (GDF-15), Matrix Metalloproteinases 1 and 9, Tissue Inhibitor of Metalloproteinases 1 (TIMP 1) and Suppression of Tumorigenicity 2 (ST-2). Blood concentrations of these biomarkers after 6 and 42 months were analyzed by the use of T-tests, repeated measures of variance, and factor analyses.RESULTS: Compared with placebo, in those receiving supplementation with selenium and coenzyme Q10, all biomarkers except ST2 showed significant decreased concentrations in blood. The changes in concentrations, that is, effects sizes as given by partial eta2 caused by the intervention were considered small to medium.CONCLUSION: The significantly decreased biomarker concentrations in those on active treatment with selenium and coenzyme Q10 compared with those on placebo after 36 months of intervention presumably reflect less fibrogenic activity as a result of the intervention. These observations might indicate that reduced fibrosis precedes the reported improvement in cardiac function, thereby explaining some of the positive clinical effects caused by the intervention. © 2017 BioFactors, 2017.
9.	Alnegren, Patrik, 1988, et al. (författare) Degradation of ferritic stainless steels under conditions used for solid oxide fuel cells and electrolyzers at varying oxygen pressures 2016 Ingår i: Corrosion Science. - : Elsevier BV. - 0010-938X. ; 110, s. 200-212 Tidskriftsartikel (refereegranskat)abstract Four commercial ferritic stainless steels were tested at 850 °C in oxygen pressures ranging from 10-4 to 1 atm, in order to investigate the isolated effect of oxygen pressure on corrosion, in the context of solid oxide electrolysis cells. The oxidation rates of all steels were essentially independent of oxygen partial pressure, which indicates n-type behavior. FIB/SEM analysis revealed that the grain size of the oxides was found to decrease at lower oxygen pressures. Volatile Cr species evaporation in pure oxygen was significantly lower than what has been reported for simulated solid oxide fuel cell environments with humid air.
10.	Alnegren, Patrik, 1988, et al. (författare) Degradation of Ferritic steel interconnects in SOEC environments 2013 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. ; 57:1, s. 2261-2270 Konferensbidrag (refereegranskat)abstract This study investigates the corrosion performance of selected ferritic steels in simulated solid oxide electrolysis cell (SOEC) environments for exposure times up 500 h. Ferritic steels have many properties that are desirable for interconnects but suffer from oxidation and chromium evaporation over time. Four different FeCr alloys have been exposed in different concentrations of dry O2 (anode side) and in 34 % H2O -3 % H2-Ar (cathode side) at 850 °C and gravimetrical measurements have been performed to study oxidation rates. Chromium evaporation has been measured and compared for the oxygen containing environments. Chromium evaporation was found to vary largely with oxygen partial pressure, while the oxidation rate of the steels did not vary substantially in the different oxygen partial pressures. Differences in oxidation behavior of the steels were observed between the exposures in dry O2 and in 34 % H2O -3 % H2 -Ar. Both reduced and increased oxidation rates were observed in the cathode side atmosphere compared to the oxygen side atmosphere for different materials.
11.	Alnegren, Patrik, 1988, et al. (författare) Metallic Bipolar Plates for High Temperature Polymer Electrolyte Membrane Fuel Cells 2016 Ingår i: Fuel Cells. - : Wiley. - 1615-6846 .- 1615-6854. ; 16:1, s. 39-45 Tidskriftsartikel (refereegranskat)abstract High temperature polymer membrane fuel cells (HTPEMFCs) are promising devices for future mobile applications. To minimize phosphoric acid migration from the membranes and to reduce the total stack weight and size metallic bipolar plates are a promising alternative. So far only very few published results are available on the use of metallic bipolar plates in HTPEMFCs. During this work a single test cell was equipped with metallic endplates to investigate the possibility of using metallic bipolar plates in HTPEMFC stacks. Furthermore we tried to simulate the environments present in an HTPEMFC by furnace exposures in an attempt to develop a simplified test method for accelerated corrosion of bipolar plate materials. It was found that the performance of the HTPEM test cell decreased by about 15 mu V h(-1). More corrosion products were seen on the cathode side samples, whereas on the anode side sample the corrosion attack of the steel was more severe. These results were successfully replicated in simulated furnace experiments.
12.	Alnegren, Patrik, 1988, et al. (författare) Severe dual atmosphere effect at 600 °C for stainless steel 441 2016 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 301, s. 170-178 Tidskriftsartikel (refereegranskat)abstract AISI 441 foils of 0.2 mm thickness were exposed in a dual atmosphere setup in which one side was exposed to air -3% H2O and the other to Ar -5% H2 - 3% H2O. The experiment was performed at 600 °C and was referenced against exposures in air +3% H2O on both sides. The exposure conditions were chosen to simulate the conditions of an interconnect in intermediate temperature solid oxide fuel cell stacks (IT-SOFC). A strong dual atmosphere effect was observed: local breakaway corrosion was discovered after only 1000 h on samples exposed to dual atmospheres. After 3000 h iron oxide had propagated to cover the entire surface area of the sample. In comparison, the samples exposed in single atmosphere formed thin protective chromia scales on both sides even after 3000 h of exposure.
13.	Alnegren, Patrik, 1988, et al. (författare) Temperature dependence of corrosion of ferritic stainless steel in dual atmosphere at 600–800 °C 2018 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 392, s. 129-138 Tidskriftsartikel (refereegranskat)abstract The ferritic stainless steel AISI 441 (EN 1.4509) is exposed for 1000 h to air - 3% H2O on one side and to Ar - 5% H2 – 3% H2O on the other at temperatures 600, 700, and 800 °C. Conditions are chosen to mimic the environment of metallic interconnects in an operating solid oxide fuel cell (SOFC). At 600 °C, ∼25 μm thick Fe2O3/(Fe,Cr)3O4 forms on large parts of the air side of the samples. Reference samples exposed to air - 3% H2O on both sides form thin protective layers of (Cr,Mn)3O4/Cr2O3 at the same temperature. At higher temperatures, 700 and 800 °C, all samples form protective layers of (Cr,Mn)3O4/Cr2O3 regardless of exposure to single or dual atmosphere. It is concluded that corrosion resistance in a dual atmosphere has an inverse dependence on temperature. Different hypotheses for the underlying cause for the dual atmosphere effect are discussed and compared to the experimental data.
14.	Bexell, Ulf, et al. (författare) Chromium evaporation from plastically deformed pre-coated Sandvik Sanergy HT 22% Cr ferritic interconnect steel 2010 Ingår i: 2010 Conference Memory Stick 9th European SOFC Forum. - Lucerne. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Ferritic stainless steel has attracted a great deal of attention for its use as an interconnector in solid oxide fuel cells (SOFCs). The ferritic Sandvik Sanergy HT chromium steel is specially developed for interconnectors in SOFC with a unique chemical composition, which gives the alloy a good high temperature corrosion resistance as well as good surface conductivity in the formed chromium oxide scale. However, chromium evaporation from metallic interconnectors in SOFC fuel cells tends to poison the cathode of the fuel cell. Furthermore, the evaporation of chromium species from the oxide surface tends to increase the oxidation rate resulting in increased contact resistance. It is nowadays well known that thin coatings of e.g. cobalt can substantially reduce the chromium evaporation from the interconnectors. In this study, a 22% Cr ferritic steel, Sandvik Sanergy HT has been coated with a thin metallic cobalt film. The coated material was plastically deformed and the effect of chromium evaporation was studied as a function of the degree of deformation. Coated samples are also compared to uncoated material. The results show that the metallic cobalt film cracks when the steel sheet is formed but the chromium evaporation is more or less unaffected.
15.	Bonaca, MP, et al. (författare) Long-term use of ticagrelor in patients with prior myocardial infarction 2015 Ingår i: The New England journal of medicine. - 1533-4406. ; 372:19, s. 1791-1800 Tidskriftsartikel (refereegranskat)
16.	Buse, Eberhard, et al. (författare) The placenta in toxicology. Part I : Animal models in toxicology 2014 Ingår i: Toxicologic pathology (Print). - : Sage Publications. - 0192-6233 .- 1533-1601. ; 42:2, s. 314-326 Forskningsöversikt (refereegranskat)abstract The immune system represents a key defense mechanism against potential pathogens and adverse non-self materials. During pregnancy, the placenta is the point of contact between the maternal organism and non-self proteins of the fetal allograft and hence undoubtedly fulfils immune functions. In the placenta bacteria, foreign (non-self) proteins and proteins that might be introduced in toxicological studies or by medication are barred from reaching the progeny, and the maternal immune system is primed for acceptance of non-maternal fetal protein. Both immunologic protection of the fetus and acceptance of the fetus by the mother require effective mechanisms to prevent an immunologic fetomaternal conflict and to keep both organisms in balance. This is why the placenta requires toxicological consideration in view of its immune organ function. The following articles deal with placenta immune-, control-, and tolerance mechanisms in view of both fetal and maternal aspects. Furthermore, models for experimental access to placental immune function are addressed and the pathological evaluation is elucidated. "The Placenta as an Immune Organ and Its Relevance in Toxicological Studies" was subject of a continuing education course at the 2012 Society of Toxicologic Pathology meeting held in Boston, MA.
17.	Canovic, Sead, 1979, et al. (författare) Oxidation of Co- and Ce-nanocoated FeCr steels: A microstructural investigation 2013 Ingår i: Surface and Coatings Technology. - : Elsevier BV. - 0257-8972. ; 215, s. 62-74 Tidskriftsartikel (refereegranskat)abstract The effect of novel Co and Ce nanocoatings on oxidation behaviour and chromium volatilization from a commercial Fe-22Cr steel (Sanergy HT) developed for solid oxide fuel cell interconnect applications is investigated. Three different coatings (10 nm Ce, 640 nm Co and 10 nm Ce + 640 nm Co) are studied. Uncoated and nanocoated samples are exposed isothermally at 850 C in the air with 3% H2O for 168 h. The detailed microstructure of the different coatings is investigated. The surface morphology and microstructure of the oxide scales are characterized by using scanning electron microscopy (SEM), transmission electron microscopy (TEM), scanning transmission electron microscopy (STEM) and energy dispersive X-ray analysis (EDX). Cross-section TEM thin foils are prepared by using a combined FIB/SEM (focused ion beam/scanning electron microscope) instrument. A 640 nm cobalt coating strongly inhibits Cr volatilization but has only minor effects on oxidation rate. In contrast, a 10 nm Ce coating decreases the oxidation rate but has no significant effects on chromium volatilization. Combining the two coatings, i.e., applying a 640 nm Co coating on top of the 10 nm Ce, effectively reduces Cr evaporation and slows down the rate of alloy oxidation.
18.	Cline, J Mark, et al. (författare) The placenta in toxicology. Part III : Pathologic assessment of the placenta 2014 Ingår i: Toxicologic pathology (Print). - : Sage Publications. - 0192-6233 .- 1533-1601. ; 42:2, s. 339-344 Tidskriftsartikel (refereegranskat)abstract This short review is derived from the peer-reviewed literature and the experience and case materials of the authors. Brief illustrated summaries are presented on the gross and histologic normal anatomy of rodent and macaque placentas, including typical organ weights, with comments on differences from the human placenta. Common incidental findings, background lesions, and induced toxic lesions are addressed, and a recommended strategy for pathologic evaluation of placentas is provided.
19.	Falk Windisch, Hannes, 1984, et al. (författare) Chromium vaporization from mechanically deformed pre-coated interconnects in Solid Oxide Fuel Cells 2015 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 297, s. 217-223 Tidskriftsartikel (refereegranskat)abstract Cathode poisoning, associated with Cr evaporation from interconnect material, is one of the most important degradation mechanisms in Solid Oxide Fuel Cells when Cr2O3-forming steels are used as the interconnect material. Coating these steels with a thin Co layer has proven to decrease Cr vaporization. To reduce production costs, it is suggested that thin metallic PVD coatings be applied to each steel strip before pressing the material into interconnect shape. This process would enable high volume production without the need for an extra post-coating step. However, when the pre-coated material is mechanically deformed, cracks may form and lower the quality of the coating. In the present study, Chromium volatilization is measured in an air-3% H2O environment at 850 C for 336 h. Three materials coated with 600 nm Co are investigated and compared to an uncoated material. The effect of deformation is investigated on real interconnects. Microscopy observations reveal the presence of cracks in the order of several μm on the deformed pre-coated steel. However, upon exposure, the cracks can heal and form a continuous surface oxide rich in Co and Mn. As an effect of the rapid healing, no increase in Cr vaporization is measured for the pre-coated material.
20.	Falk Windisch, Hannes, 1984, et al. (författare) Co- and Ce/Co-coated ferritic stainless steel as interconnect material for Intermediate Temperature Solid Oxide Fuel Cells 2017 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 343, s. 1-10 Tidskriftsartikel (refereegranskat)abstract Chromium species volatilization, oxide scale growth, and electrical scale resistance were studied at 650 and 750 °C for thin metallic Co- and Ce/Co-coated steels intended to be utilized as the interconnect material in Intermediate Temperature Solid Oxide Fuel Cells (IT-SOFC). Mass gain was recorded to follow oxidation kinetics, chromium evaporation was measured using the denuder technique and Area Specific Resistance (ASR) measurements were carried out on 500 h pre-exposed samples. The microstructure of thermally grown oxide scales was characterized using Scanning Electron Microscopy (SEM), Scanning Transmission Electron Microscopy (STEM), and Energy Dispersive X-Ray Analysis (EDX). The findings of this study show that a decrease in temperature not only leads to thinner oxide scales and less Cr vaporization but also to a significant change in the chemical composition of the oxide scale. Very low ASR values (below 10 m? cm2) were measured for both Co- and Ce/Co-coated steel at 650 and 750 °C, indicating that the observed change in the chemical composition of the Co spinel does not have any noticeable influence on the ASR. Instead it is suggested that the Cr2O3 scale is expected to be the main contributor to the ASR, even at temperatures as low as 650 °C.
21.	Falk Windisch, Hannes, 1984, et al. (författare) Determination of the oxide scale growth mechanism using 18O-tracer experiments in combination with Transmission Electron Microscopy and nanoscale Secondary Ion Mass Spectrometry 2018 Ingår i: Materials Characterization. - : Elsevier BV. - 1044-5803. ; 136, s. 128-133 Tidskriftsartikel (refereegranskat)abstract Two-stage 18 O 2 / 16 O 2 exposures can be used to investigate the effect that alloying elements, secondary phases, or surface treatments have on the high temperature oxidation behaviour of certain materials. During subsequent exposures to 16 O 2 - and 18 O 2 -rich atmospheres, 16 O- and 18 O-rich layers are formed. Analysis of the layers using Seco ndary Ion Mass Spectrometry (SIMS) depth profiling allows for conclusions to be drawn about the oxide scale growth mechanism. The conclusions are, however, not entirely unambiguous due to the limited lateral resolution of the technology. Rough surface topography and the thickness variation of the oxide scale over the analysed volume add to the ambiguity of the findings. In this study, an Fe-20%Cr alloy was exposed to both 18 O- and 16 O-rich environments at 850 °C. Two methods were used to analyse the thermally grown Cr 2 O 3 scale: (1) traditional SIMS depth profiling and (2) preparation of a cross-sectional lamellae for Transmission Electron Microscopy (TEM), which, subsequently, was analysed in a NanoSIMS. The NanoSIMS 16 O and 18 O elemental maps were then superimposed on the TEM image. In comparison with traditional SIMS depth profiling, the nanoSIMS elemental maps reveal detailed information about local oxide growth in different parts of an oxide scale. Moreover, a clear 16 O/ 18 O interface can be seen in the nanoSIMS maps, which is not the case in the sputter depth profiles. The findings of this study show that the aforementioned issues associated with sputter depth profiling can be eliminated by mapping a cross-section of an oxide scale using high resolution nanoSIMS.
22.	Falk Windisch, Hannes, 1984, et al. (författare) Influence of chromium evaporation and oxidation on interconnect steels at 650-850°C 2013 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. ; 57:1, s. 2225-2233 Konferensbidrag (refereegranskat)abstract Chromium evaporation and oxide scale growth are two important degradation mechanisms in SOFCs when chromia-forming alloys are used as the interconnect material. In this paper the influence of temperature on both mechanisms were studied. Isothermal exposures were carried out for 24, 168 and 500h at 650, 750 and 850°C in an air-3%H2O atmosphere. In the second part uncoated and metallic nano-coated samples were exposed for 3000h. This study clearly points out the relevance of Cr-evaporation at reduced temperatures and the importance of high quality coatings not only to protect the cell from cathode poisoning but also to reduce the risk of Cr-depletion within the interconnect steel.
23.	Falk Windisch, Hannes, 1984, et al. (författare) Metallic thin-film Co- and Ce/Co-coated steels as interconnect material in IT-SOFC 2017 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. - 9781607685395 ; 78:1, s. 1607-1614 Konferensbidrag (refereegranskat)abstract Cr vaporization, oxide scale growth, and the electrical scale resistance (ASR) were studied at 650°C on coated interconnects intended for IT-SOFC applications. The custom-made SOFC interconnect steel Sanergy HT was coated with thin-film Co- and Ce/Co-coatings and compared to the less expensive substrate steel AISI 441 which was coated with Ce/Co and a 15-20 μm thick commercial MCO-coating. All coated materials mitigated Cr vaporization, and due to the very thin chromia scales formed at the low exposure temperature, ASR values below 10 mΩcm 2 were measured for all materials after 500 h at 650°C. The results in this study show that thin-film metallic Co- and Ce/Co-coated steels show excellent properties as interconnect materials for IT-SOFCs. Thick MCO-coatings can also be used at low temperatures; however, the coating method might be a critical issue for lowtemperature applications.
24.	Falk Windisch, Hannes, 1984, et al. (författare) Pre-coated Ce/Co-coated steel: Mitigating Cr vaporization, increasing corrosion resistance at competitive cost 2015 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. - 9781607685395 ; 68:1, s. 1617-1623 Konferensbidrag (refereegranskat)abstract Cr vaporization and oxide scale growth are probably the two most detrimental degradation mechanisms associated to Cr2O3-forming alloys as interconnect material in SOFC. Both issues can be improved by the application of coatings. However, the use of coatings increase material cost. To reduce coating costs it is suggested that large amounts of steel can be coated before shaping the pre-coated material into an interconnect. The present study investigates the effectiveness of thin Ce and Co coatings on the cost effective steel AISI 441 with respect to Cr vaporization and corrosion resistance. Furthermore, the effect of mechanical deformation of the coated steel is examined. The results revealed that when the pre-coated steel is deformed, large cracks are formed. However, upon exposure those cracks can heal forming a continuous surface oxide rich in Co and Mn. As an effect of the rapid healing, no increase in Cr vaporization was measured.
25.	Falk Windisch, Hannes, 1984, et al. (författare) The Effect of Metallic Co-Coating Thickness on Ferritic Stainless Steels Intended for Use as Interconnect Material in Intermediate Temperature Solid Oxide Fuel Cells 2018 Ingår i: Oxidation of Metals. - : Springer Science and Business Media LLC. - 1573-4889 .- 0030-770X. ; 89:1-2, s. 233-250 Tidskriftsartikel (refereegranskat)abstract The effect of metallic Co-coating thickness on ferritic stainless steels is investigated. This material is suggested to be used as interconnect material in intermediate temperature solid oxide fuel cells. Uncoated, 200-, 600-, 1000-, and 1500-nm Co-coated Sanergy HT is isothermally exposed for up to 500 h in air at 650 A degrees C. Mass gain is recorded to follow oxidation kinetics, and area-specific resistance (ASR) measurements are conducted on samples exposed for 168 and 500 h. The microstructure of the thermally grown oxide scales is characterized utilizing scanning electron microscopy and energy-dispersive X-ray analysis on broad ion beam-milled cross sections. A clear increase in ASR as a function of Co-coating thickness is observed. However, the increase in ASR, as an effect of a thicker Co-coating, is correlated with thicker (Cr,Fe)(2)O-3 scales formed on these materials and not to an increase in Co spinel top layer thickness.
26.	Falk Windisch, Hannes, 1984, et al. (författare) The effect of temperature on chromium vaporization and oxide scale growth on interconnect steels for Solid Oxide Fuel Cells 2015 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 287, s. 25-35 Tidskriftsartikel (refereegranskat)abstract Chromium vaporization and oxide scale growth are probably the two most important degradation mechanisms associated with the interconnect in Solid Oxide Fuel Cells (SOFCs) when Cr2O3-forming alloys are used as the interconnect material. This study examines the influence of temperature on both mechanisms. Two commercially available steels; Crofer 22 H and Sanergy HT, were isothermally exposed at 650, 750 and 850 °C in an air-3% H2O atmosphere with a high flow rate. Volatile chromium species were collected using the denuder technique. The microstructure of thermally grown oxide scales was characterized using Scanning Electron Microscopy (SEM), Energy Dispersive X-Ray Analysis (EDX) and X-Ray Diffraction (XRD). The findings of this study show that although Cr evaporation is reduced with lower temperature, its relative importance compared to oxide scale growth is greater.
27.	Froitzheim, Jan, 1981, et al. (författare) Investigation of Chromium Volatilization from FeCr Interconnects by a Denuder Technique 2010 Ingår i: Journal of the Electrochemical Society. - : The Electrochemical Society. - 1945-7111 .- 0013-4651. ; 157:9, s. B1295-B1300 Tidskriftsartikel (refereegranskat)abstract A technique is presented for accurate and time-resolved quantification of chromium volatilization from alloys at high temperature. A denuder tube which is coated with Na2CO3 is placed downstream of the samples. CrO2(OH)(2) that evaporated from the samples is collected on the denuder and converted to the thermally stable Na2CrO4. The chromate is then dissolved in water and determined quantitatively. Three commercially available ferritic 22% Cr steels intended for use as solid oxide fuel cell interconnect materials (Sanergy HT, Crofer 22 APU, and ZMG 232) have been investigated with respect to chromium volatilization and oxidation rate. The effect on chromium volatilization of a submicrometer cobalt coating on the steel surface is reported. Comparisons are made with a conventional thick ceramic coating. The experiments are carried out at 850 degrees C in N-2 - 20% O-2 - 3% H2O atmosphere. The submicrometer Co coatings proved to be very efficient, reducing Cr volatilization by 1 order of magnitude. Microscopic studies show that both uncoated steel and steel coated with a submicrometer cobalt film develop two-layered oxide scales with the bottom part consisting of a Cr-rich corundum-type oxide. The uncoated samples develop a top layer consisting of (Cr, Mn)(3)O-4 oxide, whereas the Co-coated samples exhibit a top layer consisting of Co-rich spinel oxide. (C) 2010 The Electrochemical Society. [DOI: 10.1149/1.3462987] All rights reserved.
28.	Froitzheim, Jan, 1981, et al. (författare) Long term study of Cr evaporation and high temperature corrosion behaviour of Co coated ferritic steel for solid oxide fuel cell interconnects 2012 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 220, s. 217-227 Tidskriftsartikel (refereegranskat)abstract The oxidation behaviour of the uncoated ferritic Fe-22Cr steel Sanergy HT is compared with an 640 nm Co coated version of the same material. The materials have been subject to corrosion and Cr volatilization measurements in air for up to 3000 h at 850 degrees C. Oxidation tests have been carried out both isothermal and discontinuously. The volatilization measurements were carried out using a recently developed denuder technique, which allows to quantify Cr evaporation in a time resolved manner. The oxidation process is studied from very initial phases (>15 s) to long term behaviour (3000 h). The formed oxide scales are analysed by XRD, SEM/EDX as well as TEM/EDX.The results show that both materials form an oxide scale with an inner layer of Cr2O3 and a spinel layer on top. In the case of the uncoated material, the spinel layer is of (Cr,Mn)(3)O-4 type while in the presence of a Co coating a (Co,Mn,Fe)(3)O-4 is formed. The Cr evaporation measurements show that despite the fact that the Co coating is very thin (640 nm) it effectively blocks Cr evaporation for at least 3000 h. This is in line with TEM analysis showing that after 3000 h there is only a low Cr content in the outer oxide scale. This long term stability indicates the suitability of the coated material as solid oxide fuel cell (SOFC) interconnect.
29.	Froitzheim, Jan, 1981, et al. (författare) Multifunctional Nano-Coatings for SOFC Interconnects 2011 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. - 9781607682127 ; 35:1, s. 2503-2508 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 multilayered nano coatings. The best coatings combine a Cr retention layer (800nm Co) with a 10nm layer of Ce that reduces the corrosion rate of the metallic interconnect. Such coatings might be a cost efficient way to meet the required lifetime targets for SOFC interconnects. The Cr evaporation measurements are carried out with a recently developed denuder technique which allows time resolved quantification of volatile chromium species. Downstream of the samples a denuder tube is placed which collects any CrO2(OH)(2) evaporating from the samples.
30.	Froitzheim, Jan, 1981, et al. (författare) Nano coated interconnects for SOFC (NaCoSOFC) 2013 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. ; 57:1, s. 2187-2193 Konferensbidrag (refereegranskat)abstract The NaCoSOFC project is focused on the development of nano coatings for SOFC interconnects. The project is sponsored by the Nordic Top Level Research Initiative and has four project partners: Sandvik Materials Technology which is producing coated interconnects, Chalmers University of Technology and the University of Oslo that characterize samples with respect to e.g. corrosion, Cr evaporation and ASR as well as Topsoe Fuel Cell that is testing the developed interconnects in its stacks. The developed coatings are based on a combination of Co with RE elements and exhibit high corrosion resistance, 10 fold decrease in Cr evaporation and ASR values that are approximately 50% of the uncoated material.
31.	Froitzheim, Jan, 1981, et al. (författare) Nanocoatings for SOFC interconnects - Mitigating chromium volatilization and improving corrosion properties 2011 Ingår i: Materials Science Forum. - 1662-9752 .- 0255-5476. - 9783037852354 ; 696, s. 412-416 Konferensbidrag (refereegranskat)abstract Two important degradation mechanisms in Solid Oxide Fuel Cells (SOFC) are directly related to the metallic interconnects. The formation of volatile chromium oxides from metallic interconnects commonly causes fast degradation in cell performance due to poisoning the cathode. Secondly is the ability of the metallic interconnect to form a thin protective oxide one of the most important lifetime limiting factors for SOFC. Chromium volatilization of various uncoated steels is studied as a function of temperature by a recently developed denuder technique which allows time resolved quantification of volatile chromium species. The inhibition of Cr evaporation by Co thin film coatings (800nm) is investigated; it will be shown that these coatings are more effective than much thicker ceramic coatings that are commonly used for this purpose. In order to increase the lifetime of the metallic components in SOFC nano-coatings of reactive elements (RE) have been investigated as well. The application of such coatings can reduce the corrosion rates substantially and thus increase the lifetime of the fuel cell stack. It will be shown that it is possible to combine the positive effects of RE with the beneficial effects of a Co coating and thus to obtain an interconnect material with low Cr evaporation and increased oxidation resistance.
32.	Fryk, Emanuel, et al. (författare) Microdialysis and proteomics of subcutaneous interstitial fluid reveals increased galectin-1 in type 2 diabetes patients 2016 Ingår i: Metabolism-Clinical and Experimental. - : Elsevier BV. - 0026-0495 .- 1532-8600. ; 65:7, s. 998-1006 Tidskriftsartikel (refereegranskat)abstract Objective. To identify a potential therapeutic target for type 2 diabetes by comparing the subcutaneous interstitial fluid from type 2 diabetes patients and healthy men. Methods. Proteomics was performed on the interstitial fluid of subcutaneous adipose tissue obtained by microdialysis from 7 type 2 diabetes patients and 8 healthy participants. 851 proteins were detected, of which 36 (including galectin-1) showed significantly altered expression in type 2 diabetes. We also measured galectin-1 expression in: (1) adipocytes isolated from adipose tissue biopsies from these participants; (2) subcutaneous adipose tissue of 24 obese participants before, during and after 16 weeks on a very low calorie diet (VLCD); and (3) adipocytes isolated from 6 healthy young participants after 4 weeks on a diet and lifestyle intervention to promote weight gain. We also determined the effect of galectin-1 on glucose uptake in human adipose tissue. Results. Galectin-1 protein levels were elevated in subcutaneous dialysates from type 2 diabetes compared with healthy controls (p < 0.05). In agreement, galectin-1 mRNA expression was increased in adipocytes from the type 2 diabetes patients (p < 0.05). Furthermore, galectin-1 mRNA expression was decreased in adipose tissue after VLCD (p < 0.05) and increased by overfeeding (p < 0.05). Co-incubation of isolated human adipocytes with galectin-1 reduced glucose uptake (p < 0.05) but this was independent of the insulin signal. Conclusion. Proteomics of the interstitial fluid in subcutaneous adipose tissue in vivo identified a novel adipokine, galectin-1, with a potential role in the pathophysiology of type 2 diabetes. (C) 2016 Elsevier Inc. All rights reserved.
33.	Goebel, Claudia, 1988, et al. (författare) Does the conductivity of interconnect coatings matter for solid oxide fuel cell applications? 2018 Ingår i: Journal of Power Sources. - : Elsevier BV. - 0378-7753. ; 383, s. 110-114 Tidskriftsartikel (refereegranskat)abstract The present work aims to quantify the influence of typical interconnect coatings used for solid oxide fuel cells (SOFC) on area specific resistance (ASR). To quantify the effect of the coating, the dependency of coating thickness on the ASR is examined on Crofer 22 APU at 600 °C. Three different Co coating thicknesses are investigated, 600 nm, 1500 nm, and 3000 nm. Except for the reference samples, the material is pre-oxidized prior to coating to mitigate the outward diffusion of iron and consequent formation of poorly conducting (Co,Fe) 3 O 4 spinel. Exposures are carried out at 600 °C in stagnant laboratory air for 500 h and subsequent ASR measurements are performed. Additionally the microstructure is investigated with scanning electron microscopy (SEM). On all pre-oxidized samples, a homogenous dense Co 3 O 4 top layer is observed beneath which a thin layer of Cr 2 O 3 is present. As the ASR values range between 7 and 12 mΩcm 2 for all pre-oxidized samples, even though different Co 3 O 4 thicknesses are observed, the results strongly suggest that for most applicable cases the impact of the coating on ASR is negligible and the main contributor is Cr 2 O 3 .
34.	Goebel, Claudia, 1988, et al. (författare) Influence of pre-oxidation on dual atmosphere effect on AISI 441 interconnects for solid oxide fuel cell applications 2017 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. ; 78:1, s. 1559-1563 Konferensbidrag (refereegranskat)abstract In previous studies an extreme dual atmosphere effect on the airfacing side of AISI 441 at 600°C was observed. However indications showed that pre-oxidation of the material might have a beneficial effect on the corrosion resistance in dual atmosphere. To examine this further we pre-oxidized AISI 441 samples for 0 min, 11 min, 45 min, 180 min and 280 min and subsequently exposed these at 600 °C for 500 h under dual atmosphere conditions. Photographs of the air-facing sides were taken throughout exposure to monitor the corrosion behavior. SEM analysis was performed on all samples after exposure.
35.	Goebel, Claudia, 1988, et al. (författare) Long term (4 years) performance of Co/Ce coated 441 for SOFC interconnect applications 2017 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. ; 78:1, s. 1675-1679 Konferensbidrag (refereegranskat)abstract Co/Ce coated 441 samples were exposed at 800°C in laboratory air for up to 37 000 h and subsequently characterized using different techniques. Mass gain data of all samples were recorded throughout exposure. Cr-evaporation measurements were conducted and compared with unexposed Co/Ce coated AISI 441 as well as unexposed and uncoated AISI 441. Furthermore SEM analysis on BIB cross-sections was performed on 7 000 h, 23 000 h and 35 000 h exposed Co/Ce coated 441.
36.	Goebel, Claudia, 1988, et al. (författare) The effect of pre-oxidation parameters on the corrosion behavior of AISI 441 in dual atmosphere 2018 Ingår i: International Journal of Hydrogen Energy. - : Elsevier BV. - 0360-3199. ; 43:31, s. 14665-14674 Tidskriftsartikel (refereegranskat)abstract Dual atmosphere conditions have been shown to be detrimental for the ferritic stainless steel interconnects used in solid oxide fuel cells (SOFC) under certain conditions. In the present work, we analyze the influence of pre-oxidation on corrosion resistance in dual atmosphere with regard to two parameters: the pre-oxidation time and the pre-oxidation location (pre-oxidation layer on the air-facing side or the hydrogen-facing side). The steel AISI 441 is investigated and pre-oxidation is achieved in air at 800 °C. To examine the influence of pre-oxidation time on corrosion behavior, five different pre-oxidation times are used: 0, 11, 45, 180, and 280 min. The samples are exposed discontinuously to dual atmosphere for 1000 h at 600 °C. Photographs, taken throughout the exposure, show that the pre-oxidation time correlates with the onset of breakaway corrosion. To analyze the influence of pre-oxidation location on corrosion behavior, the samples are pre-oxidized for 180 min, and then a pre-oxidation layer is removed from one side of the sample. Subsequent dual atmosphere exposure at 600 °C for 500 h shows that the pre-oxidation layer on the hydrogen-facing side is more important for corrosion resistance in dual atmosphere than the pre-oxidation layer on the air-facing side.
37.	Goebel, Claudia, 1988, et al. (författare) The influence of different factors on the dual atmosphere effect observed for AISI 441 interconnects used in solid oxide fuel cells 2019 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. ; 91:1, s. 2261-2266 Konferensbidrag (refereegranskat)abstract Interconnects used in solid oxide fuel cells are subjected to dual atmosphere corrosion at 600 °C. In this work we show that the dual atmosphere effect is dependent on the thickness of the steel sheet. For this AISI 441 with varying thicknesses was exposed to dual atmosphere at 600 °C for 336 h. Before and after exposure photographs were taken to analyze the progress of corrosion on the air-facing side of the steel samples. Additionally, scanning electron microscopy and energy dispersive x-ray diffraction (SEM/EDX) analysis was conducted on all exposed samples. It was found that thinner samples showed increased breakaway oxidation than thicker samples.
38.	Günther, Torsten, et al. (författare) Population genomics of Mesolithic Scandinavia : Investigating early postglacial migration routes and high-latitude adaptation 2018 Ingår i: PLoS biology. - : Public Library of Science (PLoS). - 1544-9173 .- 1545-7885. ; 16:1 Tidskriftsartikel (refereegranskat)abstract Scandinavia was one of the last geographic areas in Europe to become habitable for humans after the Last Glacial Maximum (LGM). However, the routes and genetic composition of these postglacial migrants remain unclear. We sequenced the genomes, up to 57x coverage, of seven hunter-gatherers excavated across Scandinavia and dated from 9,500-6,000 years before present (BP). Surprisingly, among the Scandinavian Mesolithic individuals, the genetic data display an east-west genetic gradient that opposes the pattern seen in other parts of Mesolithic Europe. Our results suggest two different early postglacial migrations into Scandinavia: initially from the south, and later, from the northeast. The latter followed the ice-free Norwegian north Atlantic coast, along which novel and advanced pressure-blade stone-tool techniques may have spread. These two groups met and mixed in Scandinavia, creating a genetically diverse population, which shows patterns of genetic adaptation to high latitude environments. These potential adaptations include high frequencies of low pigmentation variants and a gene region associated with physical performance, which shows strong continuity into modern-day northern Europeans.
39.	Göhner, Claudia, et al. (författare) The placenta in toxicology. Part IV : Battery of toxicological test systems based on human placenta 2014 Ingår i: Toxicologic pathology (Print). - : Sage Publications. - 0192-6233 .- 1533-1601. ; 42:2, s. 345-351 Tidskriftsartikel (refereegranskat)abstract This review summarizes the potential and also some limitations of using human placentas, or placental cells and structures for toxicology testing. The placenta contains a wide spectrum of cell types and tissues, such as trophoblast cells, immune cells, fibroblasts, stem cells, endothelial cells, vessels, glands, membranes, and many others. It may be expected that in many cases the relevance of results obtained from human placenta will be higher than those from animal models due to species specificity of metabolism and placental structure. For practical and economical reasons, we propose to apply a battery of sequential experiments for analysis of potential toxicants. This should start with using cell lines, followed by testing placenta tissue explants and isolated placenta cells, and finally by application of single and dual side ex vivo placenta perfusion. With each of these steps, the relative workload increases while the number of feasible repeats decreases. Simultaneously, the predictive power enhances by increasing similarity with in vivo human conditions. Toxic effects may be detected by performing proliferation, vitality and cell death assays, analysis of protein and hormone expression, immunohistochemistry or testing functionality of signaling pathways, gene expression, transport mechanisms, and so on. When toxic effects appear at any step, the subsequent assays may be cancelled. Such a system may be useful to reduce costs and increase specificity in testing questionable toxicants. Nonetheless, it requires further standardization and end point definitions for better comparability of results from different toxicants and to estimate the respective in vivo translatability and predictive value.
40.	Karimi, Mahssa, et al. (författare) Increased neck soft tissue mass and worsening of obstructive sleep apnoea after growth hormone treatment in men with abdominal obesity : Growth hormone and obstructive sleep apnoea in abdominally obese men 2010 Ingår i: Journal of Clinical Sleep Medicine. - 1550-9389. ; 6:3, s. 256-263 Tidskriftsartikel (refereegranskat)abstract Background Risk factors for obstructive sleep apnea (OSA) are male gender, obesity and abnormalities in neck soft tissue mass. OSA is associated with both growth hormone (GH) excess and severe GH deficiency in adults. Adults with abdominal obesity have markedly suppressed GH secretion. Aim To study the effect of GH treatment on OSA in abdominally obese men with impaired glucose tolerance. Patients and Methods Forty men with abdominal obesity and glucose intolerance were randomized in a prospective, 12-month, double-blind trial to receive either GH or placebo. The treatment groups had similar BMI and waist circumference. Overnight polysomnography and computed tomography to assess muscle and fat distribution in the neck and abdomen were performed at baseline and after 12 months. Results GH treatment increased insulin-like growth-factor-1 from (mean (SD)) 168(17) to 292(28) μg/L, the apnea-hypopnea index from (n/h) 31(20) to 43(25) and oxygen-desaturation index from (n/h) 18(14) to 29(21) (p=0.0001, 0.001, 0.002). Neck transverse diameter, circumference and total cross-sectional area (p=0.007, 0.01, 0.02) increased while abdominal visceral adipose tissue (p=0.007) was reduced. No between-group differences in total sleep time, REM sleep, non-REM sleep and time spent in supine position were found. The Epworth sleepiness scale score was unchanged. Conclusions GH treatment increased the severity of OSA in abdominally obese men. The possible mechanism appears to be reflected by the GH-induced increase of measures of neck volume. The present results, to some extent, argue against that low GH/IGF-I activity is a primary cause of OSA in abdominally obese men.
41.	Lindgård, Jan, et al. (författare) Nordic Europe 2017 Ingår i: Alkali-aggregate reaction in concrete. - : Taylor & Francis. - 9781315708959 - 9781138027565 ; , s. 277-320, s. 185-211 Bokkapitel (övrigt vetenskapligt/konstnärligt)
42.	Magraso, A., et al. (författare) Reduced long term electrical resistance in Ce/Co-coated ferritic stainless steel for solid oxide fuel cell metallic interconnects 2015 Ingår i: International Journal of Hydrogen Energy. - : Elsevier BV. - 0360-3199. ; 40:27, s. 8579-8585 Tidskriftsartikel (refereegranskat)abstract The present study is focused on the influence of selected coatings on a ferritic stainless steel (Sanergy HT (TM), Sandvik) on the evolution of the area specific resistance (ASR) as a function of time at high temperature. The samples are exposed in humidified air at 850 degrees C for up to 4200 h. It combines long-term ASR measurements with the thermogravimetric behavior and microstructural analysis of the cross sections by scanning electron microscopy. The results show that uncoated and Co-coated Sanergy HT (TM) exhibit similar oxidation kinetics and comparable ASRs, while a combined Ce/Co coating improves oxidation resistance and, consequently, reduces the ASR significantly. Other reports have earlier shown that Co- (and Ce/Co)-coated Sanergy HT (TM) reduces the evaporation of volatile chromium species. Overall, the study indicates that Ce/Co-coatings will render substantially improved performance for ferritic steel interconnects for solid oxide fuel cells.
43.	Mattsson, Niklas, 1979, et al. (författare) Cerebrospinal Fluid Microglial Markers in Alzheimer's Disease: Elevated Chitotriosidase Activity but Lack of Diagnostic Utility 2011 Ingår i: NeuroMolecular Medicine. - : Springer Science and Business Media LLC. - 1535-1084 .- 1559-1174. ; 13:2, s. 151-159 Tidskriftsartikel (refereegranskat)abstract Activated microglial cells, which are the resident macrophages of the central nervous system, surround amyloid beta-plaques in Alzheimer's disease (AD) brains. Inflammation including microglial activation may contribute in AD pathogenesis, and biomarkers for this process may thus be of value to study AD pathogenesis and might facilitate development of therapies targeting these cells. We therefore examined cerebrospinal fluid (CSF) biomarkers in patients with AD, other dementias, mild cognitive impairment and in healthy controls. Samples were analyzed for markers with known association to macrophage activity, including chitotriosidase, YKL-40 (CHI3L1, HC gp-39) and chemokine CC motif ligand 2 (CCL2, MCP1). Patients with AD had higher chitotriosidase activity than controls and patients with stable mild cognitive impairment, consistent with the presence of activated microglial cells in AD brains, but with large overlaps between groups. CCL2 and YKL-40 concentrations did not differ among groups. Microglial markers are unlikely to be useful for AD diagnosis, but might be useful for identification of distinct subgroups of patients, and for the development and implementation of drugs targeting microglial pathology.
44.	Nugehalli Sachitanand, Rakshith, 1984, et al. (författare) Coatings for SOFC interconnects in fuel side environments 2015 Ingår i: ECS Transactions. - : The Electrochemical Society. - 1938-5862 .- 1938-6737. - 9781607685395 ; 68:1, s. 1575-1580 Konferensbidrag (refereegranskat)abstract This study focuses on examining the effect of PVD coatings on the oxidation performance of interconnects in fuel side environments. The ferritic steels Sanergy HT and AISI 441 were coated with nanoscale thick rare earth oxides of Ce and La. Additionally, Sanergy HT was also coated with Cu, Co and Ce/Co. The samples were exposed at 850°C in Ar-5% H2-3% H2O in a tubular furnace. Chemical analysis on the samples was subsequently performed with SEM/EDX and XRD. It was established that the Ce and La coatings brought about a ≈4x reduction in the oxidation rate while the presence of a metallic phase in the oxide (Cu and Co) negatively affected oxidation performance. Further, the La coating resulted in the formation of a perovskite phase, showing that the intrinsic electronic properties of the oxide can be tailored using coatings.
45.	Nugehalli Sachitanand, Rakshith, 1984, et al. (författare) Evaluation of the oxidation and Cr evaporation properties of selected FeCr alloys used as SOFC interconnects 2013 Ingår i: International Journal of Hydrogen Energy. - : Elsevier BV. - 0360-3199. ; 38:35, s. 15328-15334 Tidskriftsartikel (refereegranskat)abstract In recent years, a number of ferritic interconnect materials for use in solid oxide fuel cells (SOFC) have been developed and are now commercially available. Although similar, there are substantial variations in minor alloying elements. This study compares the oxidation performance of five such interconnect materials: Crofer 22 H, Crofer 22 APU (ThyssenKrupp VDM), Sanergy HT (Sandvik Materials Technology), ZMG232 G10 (Hitachi Metals) and E-Brite (ATI Allegheny Ludlum). 1000 h exposures have been carried out in tubular furnaces at 850 degrees C, with 6 l/min airflow and 3% H2O to simulate the air side atmosphere in an SOFC. In addition to the oxidation tests, time resolved in-situ chromium evaporation measurements have been carried out using a novel denuder technique. It was found that higher Mn concentrations in the alloy lead to lower Cr evaporation. Nonetheless, all steels exhibit substantial Cr volatilization and coatings are needed for most SOFC applications. Furthermore, this study demonstrates that the mass gain data alone can be misleading, and the mass loss due to Cr volatilization needs to be taken into account. Neglecting Cr evaporation results in an underestimation of the oxidation rate by between 15% and 200% for the studied steel grades.
46.	Nugehalli Sachitanand, Rakshith, 1984, et al. (författare) The Influence of Cr Evaporation on Long Term Cr Depletion Rates in Ferritic Stainless Steels 2015 Ingår i: Oxidation of Metals. - : Springer Science and Business Media LLC. - 1573-4889 .- 0030-770X. ; 84:3-4, s. 241-257 Tidskriftsartikel (refereegranskat)abstract It is shown that well defined flow rates are an essential parameter in oxidation experiments influenced by scale volatilisation. The 22 % Cr ferritic steel Sanergy HT, intended for use as an SOFC interconnect material, was exposed discontinuously over 3100 h at 850 °C in air + 3 % H2O @ 6000 sml min−1 (27 cm s−1) and stagnant conditions in a tubular reactor. Time resolved isothermal Cr evaporation measurements over 1000 h were also performed in the 6000 sml min−1 case while the stagnant exposure environment was saturated in Cr(VI) species to suppress any evaporation reactions. Mass balances based on oxidation and evaporation data were in good agreement with SEM/EDX bulk Cr concentration measurements. The time to a bulk concentration of 15 wt% Cr increased by ≈2× from ≈3000 to ≈5500 h when evaporation was suppressed. Further, it was established that a suppressed evaporation reaction affected not just the magnitude of Cr depletion in the steel but even its long term depletion rate.
47.	Nugehalli Sachitanand, Rakshith, 1984, et al. (författare) The Oxidation of Coated SOFC Interconnects in Fuel Side Environments 2016 Ingår i: Fuel Cells. - : Wiley. - 1615-6846 .- 1615-6854. ; 16:1, s. 32-38 Tidskriftsartikel (refereegranskat)abstract This study focuses on examining the effect of PVD coatings on the oxidation performance of interconnects in fuel (anode) side environments. A Fe-22Cr ferritic steel was coated with (i) Ce 10nm (ii) La 10nm and (iii) Co 600nm. The samples were exposed at 850 degrees C in Ar-5% H-2-3% H2O in a tubular furnace over 500 h. Additionally, the effect of a pre-oxidation step was investigated by exposure in air prior to the simulated fuel gas environment. Chemical analysis on the samples was subsequently performed with SEM/EDX and XRD. It was established that the Ce and La coatings brought about a factor 2-3 reduction (k(p)values of 2.16x10(-14)+/- 3.6x10(-15)g(2)cm(-4)s(-1) for the La 10nm coated steel compared to 7.72x10(-14)+/- 5.86x10(-15)g(2)cm(-4)s(-1) for the uncoated steel) in the oxidation rate while the Co coating disintegrated into metallic islands in and on the thermally grown oxide after exposure. Additionally, the La coating resulted in the formation of a continuous perovskite layer by reaction with the thermally grown oxide.
48.	Palming, Jenny, 1975, et al. (författare) Effects of dexamethasone on gene expression in human subcutaneous and omental adipose tissue 2011 Ingår i: ADA, 71st Scientific Sessions, 24 - 28 June 2011, San Diego, USA. Konferensbidrag (refereegranskat)
49.	Pereira, Maria J, 1981-, et al. (författare) FKBP5 expression in human adipose tissue increases following dexamethasone exposure and is associated with insulin resistance 2014 Ingår i: Metabolism: Clinical and Experimental. - : Elsevier BV. - 0026-0495 .- 1532-8600. ; 63:9, s. 1198-1208 Tidskriftsartikel (refereegranskat)abstract Objective To study effects of dexamethasone on gene expression in human adipose tissue aiming to identify potential novel mechanisms for glucocorticoid-induced insulin resistance. Materials/methods Subcutaneous and omental adipose tissue, obtained from non-diabetic donors (10 M/15 F; age: 28-60 years; BMI: 20.7-30.6 kg/m2), was incubated with or without dexamethasone (0.003-3 μmol/L) for 24 h. Gene expression was assessed by microarray and real time-PCR and protein expression by immunoblotting. Results FKBP5 (FK506-binding protein 5) and CNR1 (cannabinoid receptor 1) were the most responsive genes to dexamethasone in both subcutaneous and omental adipose tissue (~ 7-fold). Dexamethasone increased FKBP5 gene and protein expression in a dose-dependent manner in both depots. The gene product, FKBP51 protein, was 10-fold higher in the omental than in the subcutaneous depot, whereas the mRNA levels were similar. Higher FKBP5 gene expression in omental adipose tissue was associated with reduced insulin effects on glucose uptake in both depots. Furthermore, FKBP5 gene expression in subcutaneous adipose tissue was positively correlated with serum insulin, HOMA-IR and subcutaneous adipocyte diameter and negatively with plasma HDL-cholesterol. FKBP5 SNPs were found to be associated with type 2 diabetes and diabetes-related phenotypes in large population-based samples. Conclusions Dexamethasone exposure promotes expression of FKBP5 in adipose tissue, a gene that may be implicated in glucocorticoid-induced insulin resistance. © 2014 Elsevier Inc.
50.	Pereira, Maria João, et al. (författare) FKBP5 gene polymorphisms and expression in human adipose tissue are associated with insulin resistance and type 2 diabetes 2014 Ingår i: Diabetologia. - 0012-186X .- 1432-0428. ; 57:S1, s. S239-S239 Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)

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