| 1. |
- Aasa, Mikael, et al.
(författare)
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Cost and health outcome of primary percutaneous coronary intervention versus thrombolysis in acute ST-segment elevation myocardial infarction-Results of the Swedish Early Decision reperfusion Study (SWEDES) trial.
- 2010
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Ingår i: American heart journal. - : Elsevier BV. - 1097-6744 .- 0002-8703. ; 160:2, s. 322-8
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: In ST-elevation myocardial infarction, primary percutaneous coronary intervention (PCI) has a superior clinical outcome, but it may increase costs in comparison to thrombolysis. The aim of the study was to compare costs, clinical outcome, and quality-adjusted survival between primary PCI and thrombolysis. METHODS: Patients with ST-elevation myocardial infarction were randomized to primary PCI with adjunctive enoxaparin and abciximab (n = 101), or to enoxaparin followed by reteplase (n = 104). Data on the use of health care resources, work loss, and health-related quality of life were collected during a 1-year period. Cost-effectiveness was determined by comparing costs and quality-adjusted survival. The joint distribution of incremental costs and quality-adjusted survival was analyzed using a nonparametric bootstrap approach. RESULTS: Clinical outcome did not differ significantly between the groups. Compared with the group treated with thrombolysis, the cost of interventions was higher in the PCI-treated group ($4,602 vs $3,807; P = .047), as well as the cost of drugs ($1,309 vs $1,202; P = .001), whereas the cost of hospitalization was lower ($7,344 vs $9,278; P = .025). The cost of investigations, outpatient care, and loss of production did not differ significantly between the 2 treatment arms. Total cost and quality-adjusted survival were $25,315 and 0.759 vs $27,819 and 0.728 (both not significant) for the primary PCI and thrombolysis groups, respectively. Based on the 1-year follow-up, bootstrap analysis revealed that in 80%, 88%, and 89% of the replications, the cost per health outcome gained for PCI will be <$0, $50,000, and $100,000 respectively. CONCLUSION: In a 1-year perspective, there was a tendency toward lower costs and better health outcome after primary PCI, resulting in costs for PCI in comparison to thrombolysis that will be below the conventional threshold for cost-effectiveness in 88% of bootstrap replications.
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| 2. |
- Henriksson, Chris, 1938-, et al.
(författare)
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Evaluation of four outpatient educational programmes for patients with longstanding fibromyalgia
- 2004
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Ingår i: Journal of Rehabilitation Medicine. - : Medical Journals Sweden AB. - 1650-1977 .- 1651-2081. ; 36:5, s. 211-219
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Tidskriftsartikel (refereegranskat)abstract
- OBJECTIVE: Four programmes based on educational and cognitive principles but with a variation in total length and number of staff/patient contact hours were compared in order to gain further insight into the importance of the format of the programme for the final outcome.DESIGN: A prospective non-randomized intervention study with 191 persons with fibromyalgia. Data were collected before, after and at 1-year follow-up. Participants served as their own controls. Results within and between the programmes were calculated.METHODS: Clinical investigations before and after intervention. Questionnaires were answered before, after and at 1-year follow-up.RESULTS: Most instruments showed no significant improvements after the programme. However, some improvements were found in important variables such as attitudes, self-efficacy, vitality and "days feeling well". Results were unchanged at the 1-year follow-up and 16 persons had started working. Seven had ceased working. Participants reported frequent use of coping strategies in everyday life. No major differences could be found between the programmes. Conclusions: More comprehensive programmes did not produce better results at group level. Also short and less costly interventions based on educational and cognitive principles were valuable for persons with longstanding fibromyalgia. More attention must be given to evaluating the clinical effect of programmes.
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| 3. |
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| 4. |
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| 5. |
- Andersson, Alexander, et al.
(författare)
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Presence of Calcium Cations Stimulate Alkaline Hydrolysis of Cellulose During Kraft Pulping Conditions
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Annan publikation (övrigt vetenskapligt/konstnärligt)abstract
- Simulated kraft pulping has been performed on cotton linters fibers consisting of almost pure cellulose with varying content of calcium ions. These concentrations were obtained by soaking and drying cotton linters in calcium sulfate solutions. The viscosities of the pulped fibers were generally lower with higher calcium ion concentration and, therefore, in line with earlier suggested ideas that calcium ions could catalyze alkaline hydrolysis. The technical importance of these results is discussed.
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| 6. |
- Antonsson, Stefan, et al.
(författare)
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Adding lignin derivatives to decrease the effect of mechano-sorptive creep in linerboard
- 2008
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Ingår i: Appita journal. - 1038-6807. ; 61:6, s. 468-471
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Tidskriftsartikel (refereegranskat)abstract
- When load is applied to any type of paper while varying the relative humidity, the paper will creep more than if the same load is applied at constant humidity. This behaviour is called mechano-sorptive creep or accelerated creep, and the reasons for its occurrence in paper are still not fully understood. However, wet strength and the addition of apolar (hydrophobic) compounds to sheets have previously been suggested as factors improving the mechano-sorptive creep performance. This work evaluates a method for improving wet strength and tests the addition of a hydrophobic compound, with particular reference to mechano-sorptive creep stiffness. Wet strength was improved by subjecting kraft liner pulp to low-molecular-weight lignin, obtained by cross-flow filtration, and to the radical initiator manganese(III). The hydrophobic compound added was a suberin-like lignin derivative. Adding the suberin-like lignin derivative significantly increased the mechano-sorptive creep stiffness, even though the stiffness at 90% rh decreased in the tested samples. This was probably because of the decrease in hygroexpansion caused by this hydrophobic additive. Even though it is possible significantly to increase the wet strength of kraft liner pulp by adding manganese(III) and cross-flow-filtered lignin, doing so has no significant effect on mechano-sorptive creep stiffness.
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| 7. |
- Antonsson, Stefan, et al.
(författare)
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Biomimetic synthesis of suberin for new biomaterials
- 2005
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Ingår i: Appita Annual Conference. ; , s. 561-564
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Konferensbidrag (refereegranskat)abstract
- Suberin is the biopolymer giving cork (oak bark) its hydrophobic and resistant characteristics. It acts as a diffusion barrier in bark and roots of plants. Similarly to lignin, it is a phenolic polymer with good affinity to cellulose and other wood polysaccharides, but it also contains polyaliphatic and strongly hydrophobic elements. In order to produce a lignin derivative similar to suberin, a desired lignin starting material should be of low molecular weight and have a high content of hydroxylic phenolic groups. By means of cross flow nanofiltration of softwood kraft pulping black liquor and pH-precipitation with diluted sulphuric acid, such a lignin has been obtained. Due to the fact that too much organics entering the recovery boiler frequently is the bottleneck for pulp production increases, a removal of part of the lignin can be economically very favourable. By using this lignin together with linola oil, a linseed oil with a large amount of unsaturated structures, an attempt was made to create a new hydrophobic lignin derivative similar tosuberin. The product was analysed with FT-IR, Fourier Transformed Infra Red Spectroscopy and GPC, Gel Permeation Chromatography. The suberin like material obtained from this lignin could be polymerised on thermo mechanical pulp fibres by means of Mn(III)-driven phenolic coupling. The ability of the suberin monomers to act as a hydrophobic paper coating was evaluated with contact angle measurements and the results indicate that this lignin derivative was potentially of interest due to its capability to interact well with wood fibres and make paper hydrophobic.
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| 8. |
- Antonsson, Stefan, et al.
(författare)
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Low Mw-lignin fractions together with vegetable oils as available oligomers for novel paper-coating applications as hydrophobic barrier
- 2008
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Ingår i: Industrial crops and products (Print). - : Elsevier BV. - 0926-6690 .- 1872-633X. ; 27:1, s. 98-103
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Tidskriftsartikel (refereegranskat)abstract
- Lignin residues are available in large amounts as kraft lignin from chemical pulping processes. This lignin is mainly incinerated in recovery boilers. The recovery boilers are often the bottle-necks in the overall pulping process when pulp production increases are desired. Through cross-flow nano-filtration of the black liquor from kraft pulping, a low-molecular weight lignin fraction can be removed thus decreasing the organic load on the recovery boilers. The low-molecular weight lignin fraction furthermore exhibit different characteristics compared to other commercial kraft lignins and represents a new raw material source in novel applications. The low-molecular weight lignin was used together with a vegetable oil to produce a new hydrophobic lignin derivative similar to suberin. The lignin and the lignin derivative was analysed with FT-IR, UV-vis and SEC. The ability of the product to make paper surfaces hydrophobic was also evaluated. The results demonstrate the possibility to make a suberin-like lignin derivative that is potentially of interest in paper-coating applications due to its capability to interact well with wood fibres and make paper hydrophobic.
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| 9. |
- Antonsson, Stefan, 1979-
(författare)
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Strategies for improving kraftliner pulp properties
- 2008
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- A large part of the world paper manufacturing consists of production of corrugated board components, kraftliner and fluting, that are used in many different types of corrugated boxes. Because these boxes are stored and transported, they are often subjected to changes in relative humidity. These changes together with mechanical loads will increase the deformation of the boxes compared to the case where the same loads are applied in a static environment. This enlarged creep due to the changes in relative humidity is called mechano-sorptive or accelerated creep. Mechano-sorptive creep forces producers to use high safety factors when designing boxes, and therefore, this is one of the key properties of kraftliner boards. Different strategies to decrease mechano-sorptive creep, and to simultaneously gain more knowledge about the causes for this phenomenon in paper, are the aim of this work. Derivatised and underivatised black liquor lignins, a by-product produced in pulp mills in large quantities, have been used together with biomimetic methods, to modify the properties of kraftliner pulp. Furthermore, the properties of kraftliner pulp have been compared to other pulps in order to evaluate the influence of fibre morphological factors, such as fibre width and shape factor, on the mechano-sorptive creep. In addition the influence of the chemical composition of the kraftliner pulp has been evaluated both by means of treating a kraftliner pulp with chlorite and xylanase and by producing pulps with different chemical composition. By using lignin and biomimetic methods, to create radical coupling reactions, it has been shown that it is possible to increase the wet strength of kraftliner pulp sheets. This method of treating the pulp showed, however, no significant effects on the mechano-sorptive creep. The addition of an apolar suberin-like lignin derivative, which has been shown to be possible to produce from natural resources, did show a positive effect on mechano-sorptive creep properties, but at the expense of stiffness properties in constant climate. Different pulps were compared with a kraftliner pulp and it was observed that the ratio between tensile stiffness and hygroexpansion can be used to estimate the mechano-sorptive creep properties. The hardwood kraft pulps investigated had lower hygroexpansion, probably due to more slender and straighter fibres, and higher tensile stiffness, probably due to lower lignin content. As the lignin content was varied by different methods in kraft pulps, it was observed that increased lignin content gives an increased hygroexpansion and decreased tensile stiffness as well as an increased mechano-sorptive creep. There were also indications of increased mechano-sorptive creep due to higher xylan content.
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| 10. |
- Antonsson, Stefan, et al.
(författare)
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The influence of lignin and xylan on some kraftliner pulp properties
- 2009
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Ingår i: Nordic Pulp & Paper Research Journal. - : Walter de Gruyter GmbH. - 0283-2631 .- 2000-0669. ; 24:4, s. 403-408
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Tidskriftsartikel (refereegranskat)abstract
- This study investigates the influence of lignin and hemicellulose content on the mechanical and physical properties of softwood kraft liner pulp. Tensile properties, hygroexpansion, and mechano-sorptive creep properties were measured. The lignin and hemicellulose contents were modified by chlorite delignification and xylanase treatment. After treatment, the chemical composition of the pulps was 3-14% Klason lignin, 69-77% cellulose, 16-21% hemicellulose, and 4-7% xylan. In the tested pulps, low lignin content tended to decrease hygroexpansion as well as increase tensile stiffness and mechano-sorptive creep stiffness. Xylan contributed less to the pulp sheet properties, but at equal lignin contents, higher xylan content tended to give increased hygroexpansion and worse mechano-sorptive creep properties.
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| 11. |
- Antonsson, Stefan, 1979-
(författare)
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The Use of Lignin Derivatives to Improve Selected Paper Properties
- 2007
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Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Ved består huvudsakligen av tre typer av polymerer, cellulosa, hemicellulosa och lignin. Lignin bildas i naturen genom enzymatiskt initierad oxidativ koppling av tre olika typer av fenylpropan-enheter. Dessa bygger genom olika kol-kol- och kol-syre-bindningar upp en amorf tredimensionell polymer. När kemisk massa tillverkas bryts lignin ner och löses ut i kokluten. Luten innehåller de förbrukade kokkemikalierna och bränns generellt i en sodapanna för att regenerera kemikalierna och producera ånga. Sodapannan är emellertid dyr. Därför har den blivit produktionsbegränsande på många massabruk. Att avlägsna en del av ligninet från avluten vore därför önskvärt och att finna ekonomiskt intressanta produkter baserade på lignin från svartlut är därför ett viktigt forskningsområde . Ett lämpligt område för ligninprodukter vore som tillsatts i oblekt massa. Oblekt massa används till stor del för tillverkning av kraftliner, topp- och bottenskikten på wellpapp. När lådor av wellpapp lagras i containrar som färdas över haven, förändras den relativa luftfuktigheten. Detta gör att lådorna kollapsar lättare än om de skulle ha lagrats vid konstant luftfuktighet, även en hög sådan. Detta är på grund av det så kallade mekanosorptiva- eller accelererade krypfenomenet. Genom tillsatts av våtstyrkemedel till kraftliner eller behandla den med hydrofoba ämnen, finns indikatoner på att mekanosorptiva effekten skulle kunna minska. För att försöka minska den effekten har ett lågmolekylärt kraftlignin, som utvunnits med hjälp av tvärsflödesfiltrering av svartlut och svavelsyrafällning, använts. Genom derivatisering av detta lignin med linolja erhölls ett hydrofobt ligninderivat som uppvisar strukturella likheter med biopolymeren suberin. När detta suberinlika ligninderivat tillsätts till massa verkar det mekanosorptiva krypet minska. När lågmolekylärt lignin används tillsammans med ligninradikalinitiatorerna lackas eller mangan(III) i kraftlinermassa erhålls dessutom en våtstyrka på ca 5% av torrstyrkan. Efter aminering av detta lignin gav en tillsatts till kraftlinermassan en våtstyrka på upp till 10% av torrstyrkan. Det finns indikationer på att det mekanosorptiva krypet samtidigt minskar när dessa behandlingar görs som ger upphov till ökad våtstyrka.
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| 12. |
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| 13. |
- Arup, Ulf, et al.
(författare)
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Belonia nidarosiensis funnen i Sverige
- 2013
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Ingår i: Lavbulletinen. - 1651-6435. ; 2013:2, s. 44-48
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Tidskriftsartikel (refereegranskat)abstract
- Redan för några år sedan hittade Mikael Hagström och Jan Henriksson B. nidarosiensis på Gotland, men av flera anledningar har det tagit lite tid att få klarhet vad det var för art. Nedan beskriver de tillsammans med Ulf Arup hela historien om fynden på Gotland.
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| 14. |
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| 15. |
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| 16. |
- Azhar, Shoaib, 1980-, et al.
(författare)
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Extraction of hemicelluloses from fiberized spruce wood
- 2015
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Ingår i: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 117, s. 19-24
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Tidskriftsartikel (refereegranskat)abstract
- A novel mechanical pre-treatment method was used to separate the wood chips into fiber bundles in order to extract high molecular weight wood polymers. The mechanical pre-treatment involved chip compression in a conical plug-screw followed by defibration in a fiberizer. The fiberized wood was treated with hot water at various combinations of time and temperature in order to analyze the extraction yield of hemicelluloses at different conditions. Nearly 6 mg/g wood of galactoglucomannan was obtained at 90◦C/120min which was about three times more than what could be extracted from wood chips. The extracted carbohydrates had molecular weight ranging up to 60 kDa. About 10% of each of the extracted material had a molecular weight above 30 kDa. The extraction liquor could also be reused for consecutive extractions with successive increase in the extraction yield of hemicelluloses.
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| 17. |
- Azhar, Shoaib, et al.
(författare)
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Extraction of polymers from enzyme-treated softwood
- 2011
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Ingår i: BioResources. - 1930-2126. ; 6:4, s. 4606-4614
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Tidskriftsartikel (refereegranskat)abstract
- In a biorefinery context it is an advantage to fractionate and extract different wood components in a relatively pure form. However, one major obstacle for efficient extraction of wood polymers (lignin, polysaccharides etc.) is the covalent lignin-polysaccharide networks present in lignified cell walls. Enzymatic catalysis might be a useful tool for a controlled degradation of these networks, thereby enhancing the extraction of high molecular weight polymers. In this work, a methanol-alkali mixture was used to extract two different wood samples treated with endoxylanase and gammanase, respectively. Wood chips were pretreated with alkali prior to enzymatic treatment to enhance the cell-wall accessibility to enzymes. Extractions were also carried out on non-enzyme-treated samples to evaluate the enzymatic effects. Results showed that the enzymatic treatment increased the extraction yield, with gammanase as the more efficient of the two enzymes. Furthermore, polymers extracted from xylanase-treated wood had a higher degree of polymerization than the reference.
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| 18. |
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| 19. |
- Berglund, Jennie, et al.
(författare)
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A molecular dynamics study of the effect of glycosidic linkage type in the hemicellulose backbone on the molecular chain flexibility
- 2016
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Ingår i: The Plant Journal. - : John Wiley & Sons Ltd.. - 0960-7412 .- 1365-313X. ; 88:1, s. 56-70
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Tidskriftsartikel (refereegranskat)abstract
- The macromolecular conformation of the constituent polysaccharides in lignocellulosic biomass influences their supramolecular interactions, and therefore their function in plants and their performance in technical products. The flexibility of glycosidic linkages from the backbone of hemicelluloses was studied by evaluating the conformational freedom of the φ and ψ dihedral angles using molecular dynamic simulations, additionally selected molecules were correlated with experimental data by NMR spectroscopy. Three types of β-(1→4) glycosidic linkages involving the monosaccharides (Glcp, Xylp and Manp) present in the backbone of hemicelluloses were defined. Different di- and tetrasaccharides with combinations of such sugar monomers from hemicelluloses were simulated and free energy maps of the φ - ψ space and hydrogen bonding patterns were obtained. The glycosidic linkage between Glc-Glc or Glc-Man (C-type) was the stiffest with mainly one probable conformation; the linkage from Man-Man or Man-Glc (M-type) was similar but with an increased probability for an alternative conformation making it more flexible, and the linkage between two Xyl-units (X-type) was the most flexible with two almost equally populated conformations. Glycosidic linkages of the same type showed essentially the same conformational space in both disaccharides and in the central region of tetrasaccharides. Different probabilities of glycosidic linkage conformations in the backbone of hemicelluloses can be directly estimated from the free energy maps, which to a large degree affect the overall macromolecular conformations of these polymers. The information gained contributes to an increased understanding of hemicelluloses’ function both in the cell wall and in technical products.
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| 20. |
- Berglund, Jennie, et al.
(författare)
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Acetylation and Sugar Composition Influence the (In)Solubility of Plant beta-Mannans and Their Interaction with Cellulose Surfaces
- 2020
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Ingår i: ACS Sustainable Chemistry and Engineering. - : AMER CHEMICAL SOC. - 2168-0485. ; 8:27, s. 10027-10040
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Tidskriftsartikel (refereegranskat)abstract
- Plant beta-mannans are complex heteropolysaccharides that represent an abundant resource from lignocellulosic biomass. The influence of the molecular motifs of plant mannans on the backbone flexibility, solubility, and the interaction with cellulose was investigated by computational and experimental approaches. The regioselectivity of the acetyl substitutions at C2 and C3 distinctively influenced backbone flexibility in aqueous media, as revealed by molecular dynamic simulations. The molecular weight and degree of acetylation were tailored for two model seed mannans (galactomannan and glucomannan) and compared to spruce acetylated galactoglucomannan. The thermal stability was enhanced with increasing acetyl substitutions, independently of the type of mannan. Dynamic light scattering and atomic force microscopy revealed that the occurrence of galactosylation and a low degree of acetylation (similar to that of native acetylated galactoglucomannans) enhanced solubility/dispersibility of mannans, whereas the solubility/dispersibility decreased for higher degrees of acetylation. Mannan solubility influenced their interactions with cellulose at water-cellulose interfaces in terms of adsorbed mass and viscoelastic properties of the adsorbed mannan layers. Our results reveal that modulating the molecular motifs of plant beta-mannans influences their macromolecular conformation and physicochemical properties, with fundamental implications for their role in the plant cell wall and the design of wood-based materials.
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| 21. |
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| 22. |
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| 23. |
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| 24. |
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| 25. |
- Berglund, Jennie, et al.
(författare)
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The structure of galactoglucomannan impacts the degradation under alkaline conditions
- 2018
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Ingår i: Cellulose. - : Springer. - 0969-0239 .- 1572-882X.
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Tidskriftsartikel (refereegranskat)abstract
- Galactoglucomannan (GGM) from sprucewas studied with respect to the degradation behavior inalkaline solution. Three reference systems includinggalactomannan from locust bean gum, glucomannanfrom konjac and the linear water-soluble carboxymethylcellulose were studied with focus onmolecular weight, sugar composition, degradationproducts, as well as formed oligomers, to identifyrelative structural changes in GGM. Initially allmannan polysaccharides showed a fast decrease inthe molecular weight, which became stable in the laterstage. The degradation of the mannan polysaccharidescould be described by a function corresponding to thesum of two first order reactions; one slow that wasascribed to peeling, and one fast that was connectedwith hydrolysis. The galactose side group wasstable under conditions used in this study (150 min,90 C, 0.5 M NaOH). This could suggest that, apartfrom the covalent connection to C6 in mannose, thegalactose substitutions also interact non-covalentlywith the backbone to stabilize the structure againstdegradation. Additionally, the combination of differentbackbone sugars seems to affect the stability of thepolysaccharides. For carboxymethyl cellulose thedegradation was linear over time which furthersuggests that the structure and sugar composition playan important role for the alkaline degradation. Moleculardynamics simulations gave details about theconformational behavior of GGM oligomers in watersolution, as well as interaction between the oligomersand hydroxide ions.
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| 26. |
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| 27. |
- Berglund, Jennie, et al.
(författare)
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Wood hemicelluloses exert distinct biomechanical contributions to cellulose fibrillar networks
- 2020
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Ingår i: Nature Communications. - : Springer Nature. - 2041-1723. ; 11:1
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Tidskriftsartikel (refereegranskat)abstract
- Hemicelluloses, a family of heterogeneous polysaccharides with complex molecular structures, constitute a fundamental component of lignocellulosic biomass. However, the contribution of each hemicellulose type to the mechanical properties of secondary plant cell walls remains elusive. Here we homogeneously incorporate different combinations of extracted and purified hemicelluloses (xylans and glucomannans) from softwood and hardwood species into self-assembled networks during cellulose biosynthesis in a bacterial model, without altering the morphology and the crystallinity of the cellulose bundles. These composite hydrogels can be therefore envisioned as models of secondary plant cell walls prior to lignification. The incorporated hemicelluloses exhibit both a rigid phase having close interactions with cellulose, together with a flexible phase contributing to the multiscale architecture of the bacterial cellulose hydrogels. The wood hemicelluloses exhibit distinct biomechanical contributions, with glucomannans increasing the elastic modulus in compression, and xylans contributing to a dramatic increase of the elongation at break under tension. These diverging effects cannot be explained solely from the nature of their direct interactions with cellulose, but can be related to the distinct molecular structure of wood xylans and mannans, the multiphase architecture of the hydrogels and the aggregative effects amongst hemicellulose-coated fibrils. Our study contributes to understanding the specific roles of wood xylans and glucomannans in the biomechanical integrity of secondary cell walls in tension and compression and has significance for the development of lignocellulosic materials with controlled assembly and tailored mechanical properties.
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| 28. |
- Berglund, Jennie
(författare)
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Wood Hemicelluloses - Fundamental Insights on Biological and Technical Properties
- 2018
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Hemicelluloses are a group of heterogeneous polysaccharides representing around 30 % of wood where the dominating types are xylans, glucomannans and xyloglucans. Hemicelluloses complex molecular structure makes it difficult to understand the relationship between structure and properties entirely, and their biological role is not yet fully verified. Additionally, hemicelluloses are sensitive to chemical processing and are not utilized to their full potentials for production of value-added products such as materials, additives to food and pharmaceutical products, etc. Increased knowledge regarding their functions is important for the development of both processes and products. The aim with this work has therefore been to increase the fundamental understanding about how the structure and properties of wood hemicelluloses are correlated, and properties such as flexibility, interaction with cellulose, solubility, resistance to chemical-, thermal-, and enzymatic degradation have been explored.Molecular dynamics (MD) simulations were used to, in detail, study the structures found in wood hemicelluloses. The flexibility was evaluated by comparing the impact of backbone sugars on the conformational space and also the impact of side groups was considered. Based on the conformational space of backbone glycosidic linkages the flexibility order of hemicelluloses in an aqueous environment was determined to be: xylan > glucomannan > xyloglucan. Additionally, the impact of xylan structure on cellulose interaction was evaluated by MD methods.Hemicelluloses were extracted from birch and spruce, and were used to fabricate different composite hydrogels with bacterial cellulose. These materials were studied with regards to mechanical properties, and it was shown that galactoglucomannans mainly contributed to an increased modulus in compression, whereas the most significant effect from xylan was increased strain under uniaxial tensile testing. Besides, other polysaccharides of similar structure as galactoglucomannans were modified and used as pure, well defined, models. Acetyl groups are naturally occurring decorations of wood hemicelluloses and can also be chemically introduced. Here, mannans with different degrees of acetylation were prepared and the influence of structure on solubility in water and the organic solvent DMSO were evaluated. Furthermore, the structure and water solubility influenced the interaction with cellulose. Acetylation also showed to increase the thermal and biological stability of mannans.With chemical pulping processes in mind, the degradability of spruce galactoglucomannans in alkaline solution were studied with regards to the structure, and the content of more or less stable structural regions were proposed.
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| 29. |
- Brynolfsson, Patrik, et al.
(författare)
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ADC texture-An imaging biomarker for high-grade glioma?
- 2014
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Ingår i: Medical physics (Lancaster). - : Wiley. - 0094-2405. ; 41:10, s. 101903-
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Tidskriftsartikel (refereegranskat)abstract
- Purpose:Survival for high-grade gliomas is poor, at least partly explained by intratumoral heterogeneity contributing to treatment resistance. Radiological evaluation of treatment response is in most cases limited to assessment of tumor size months after the initiation of therapy. Diffusion-weighted magnetic resonance imaging (MRI) and its estimate of the apparent diffusion coefficient (ADC) has been widely investigated, as it reflects tumor cellularity and proliferation. The aim of this study was to investigate texture analysis of ADC images in conjunction with multivariate image analysis as a means for identification of pretreatment imaging biomarkers.Methods:Twenty-three consecutive high-grade glioma patients were treated with radiotherapy (2 Gy/60 Gy) with concomitant and adjuvant temozolomide. ADC maps and T1-weighted anatomical images with and without contrast enhancement were collected prior to treatment, and (residual) tumor contrast enhancement was delineated. A gray-level co-occurrence matrix analysis was performed on the ADC maps in a cuboid encapsulating the tumor in coronal, sagittal, and transversal planes, giving a total of 60 textural descriptors for each tumor. In addition, similar examinations and analyses were performed at day 1, week 2, and week 6 into treatment. Principal component analysis (PCA) was applied to reduce dimensionality of the data, and the five largest components (scores) were used in subsequent analyses. MRI assessment three months after completion of radiochemotherapy was used for classifying tumor progression or regression.Results:The score scatter plots revealed that the first, third, and fifth components of the pretreatment examinations exhibited a pattern that strongly correlated to survival. Two groups could be identified: one with a median survival after diagnosis of 1099 days and one with 345 days, p = 0.0001.Conclusions:By combining PCA and texture analysis, ADC texture characteristics were identified, which seems to hold pretreatment prognostic information, independent of known prognostic factors such as age, stage, and surgical procedure. These findings encourage further studies with a larger patient cohort. (C) 2014 Author(s).
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| 30. |
- Christiernin, M., et al.
(författare)
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The effects of xyloglucan on the properties of paper made from bleached kraft pulp
- 2003
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Ingår i: Nordic Pulp & Paper Research Journal. - : Walter de Gruyter GmbH. - 0283-2631 .- 2000-0669. ; 18:2, s. 182-187
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Tidskriftsartikel (refereegranskat)abstract
- Xyloglucan was adsorbed onto bleached soft-wood kraft pulp followed by preparation and analysis of handsheets with respect to sheet formation as well as sheet mechanical and optical properties. Adsorption of xyloglucan was found to be slow. After more than 20 hrs adsorption, equilibrium had not been reached. The amount of xyloglucan adsorbed increased with beating, but neither the rate of adsorption nor the quantity adsorbed was significantly affected by temperature. Xyloglucan was found to be practically irreversibly adsorbed onto the fibres and the effects of xyloglucan on paper sheet properties were investigated after thorough washing of the pulp. The adsorption characteristics of xyloglucan confirm observations by other authors on other cellulose substrates. Tensile index values for handsheets formed with the xyloglucan-containing pulps were higher than those measured for control pulps with a comparable beating degree. The light scattering coefficient was, however, not affected by xyloglucan adsorption. Hence, the increase in tensile strength is attributed to an increased relative bond strength between the fibres. Tensile strength versus tear strength relationship was similar for pulps with and without xyloglucan, but water retention value and dewatering resistance were lower for the xyloglucan treated pulps than for the reference pulps at the same tensile strength. In addition, formation was improved for pulps with adsorbed xyloglucan. The conclusion is that xyloglucan is a promising wet end additive that decreases the necessity for beating of the pulp and improves the formation of paper.
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| 31. |
- Dogaris, Ioannis, et al.
(författare)
-
Critical parameters for tall oil separation I : The importance of the ratio of fatty acids to rosin acids
- 2019
-
Ingår i: TAPPI Journal. - : TECH ASSOC PULP PAPER IND INC. - 0734-1415. ; 18:9, s. 547-555
-
Tidskriftsartikel (refereegranskat)abstract
- Tall oil is a valuable byproduct in chemical pulping of wood, and its fractions have a large spectrum of applications as chemical precursors, detergents, and fuel. High recovery of tall oil is important for the economic and environmental profile of chemical pulp mills. The purpose of this study was to investigate critical parameters of tall oil separation from black liquor. To investigate this in a controlled way, we developed a model test system using a "synthetic" black liquor (active cooking chemicals OH- and HS- ions), a complete process for soap skimming, and determination of recovered tall oil based on solvent extraction and colorimetric analysis, with good reproducibility. We used the developed system to study the effect of the ratio of fatty acids to rosin acids on tall oil separation. When high amounts of rosin acids were present, tall oil recovery was low, while high content of fatty acids above 60% significantly promoted tall oil separation. Therefore, manipulating the content of fatty acids in black liquor before the soap skimming step can significantly affect the tall oil solubility, and hence its separation. The findings open up chemical ways to improve the tall oil yield. Application: Controlling the ratio of fatty acids to rosin acids in kraft pulping can significantly affect the tall oil separation and improve its yield and quality.
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| 32. |
- Dogaris, Ioannis, et al.
(författare)
-
Study on tall oil solubility for improved resource recovery in chemical pulping of wood
- 2019
-
Ingår i: Abstracts of Papers of the American Chemical Society. - : American Chemical Society (ACS). - 0065-7727. ; 257
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Tall oil is one of the most valuable by products in chemical pulpingof wood and is considered an important renewable alternative to petroleum.Its fractions have a large spectrum of applications including chemicalprecursors, detergents and energy. High recovery of tall oil is important forthe economic, sustainability, and environmental profile of industrial chemicalpulping. The purpose of this study was to develop ways to increase the yieldof tall oil based on its solubility in black liquors.To investigate this in a controlled way, a model system with a “synthetic”black liquor and a complete methodology for soap skimming anddetermination of recovered tall oil was developed based on solvent extractionand colorimetric analysis with good reproducibility. This model system allowsinvestigations of different parameters in small scale with high control overdifferent conditions.The developed system was used to study the effect of fatty acid addition andthe effect of lignin content on improving tall oil recovery. The presence ofrosin acids in the black liquor significantly reduced soap separation, whileincreasing the fatty acid content up to 60-70% greatly improved soaprecovery. Addition of lignin reduced tall oil recovery in the case of liquors withmore than 50% fatty acids, but slightly increased recovery in liquors withmore than 50% rosin acids. Furthermore, the presence of some ligninseemed to promote separation of the tall oil (reduced its solubility), while highamounts led to inhibition of its recovery.The experimental results clearly indicated that manipulating the content offatty acids and/or lignin before the soap skimming step significantly affect thetall oil solubility, opening up for chemical ways to improve its recovery.However, experiments in real industrial liquors and pulp mill conditions shouldbe considered to assess the actual tall oil yield improvement and processeconomics.
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| 33. |
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| 34. |
- Ericsson, Mikael, 1975-, et al.
(författare)
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Non-contact Temperature Measurements using an Infrared Camera in Aerospace Welding Applications
- 2002
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Ingår i: 6th International Conference on Trends in Welding Research. - Materials Park : ASM International. ; , s. 930-935
-
Konferensbidrag (refereegranskat)abstract
- This paper describes the application of infrared (IR) thermal imaging and temperature measurements in welding applications, both on single plane plates and on an aero engine turbine component with complex geometry. Temperature profiles were measured on the plates using thermocouples (T/C) in combination with an IR camera system, and the results were compared. The IR camera was used both in line scan mode (270 Hz scan frequency) and in full frame mode (1 Hz frame rate). Different methods of surface treatments have been tested to handle the problem of the surface emissivity variations due to oxidation during welding. Results from measurements using thermocouples and IR camera is presented in the paper as well as temperature measurements using the IR camera on an turbine exhaust case (TEC) engine component.
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| 35. |
- Eriksson, Mikael, et al.
(författare)
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Klinisk stadieindelning
- 1998
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Ingår i: Onkologi. - 9147048581 ; , s. 75-79
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Bokkapitel (refereegranskat)
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| 36. |
- Feng, Leping, et al.
(författare)
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On model of gearbox noise and dynamic transmission error
- 2005
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Ingår i: Twelfth International Congresson Sound and Vibration. - 9781627481496 ; , s. 3198-3205
-
Konferensbidrag (refereegranskat)abstract
- Gearbox is an important noise source in automotive industry. Dynamic Transmission Error(DTE) describes the dynamic behaviour of the complete gear system and is closely related tothe vibrations of, and hence the noise radiated from, a gearbox. The coherence between DTEand noise radiated has been investigated previously and promising results have been obtained.The paper focuses on the models of DTE and the gearbox noise and the relation betweenthem. In order to understand the behaviour of the signals, a simple model is drawn whereDTE is modelled as the excitation source of a gear system. When the speed of rotation is notextremely high, DTE is expected to be independent of the speed of rotation when theobservation points are located on the wheel. On the other hand, the radiated sound isexpected to increase at the rate of 6 dB per double of the rotation speed, although a bigfluctuation is also expected due to the influence of the shifted frequency and hence thedifferent transfer function. Experimental data is analysed. The dynamic transmission errormeasured on a truck gearbox is separated into deterministic parts and a stochastic part. Theapplied torque has little influence on the averaged DTE of the whole gear because of the highstiffness. However, when the averaged DTE of a single tooth is concerned, the influence ofthe applied torque is rather obvious. The predicted trend of the radiated sound pressure isalso seen in the measured data.
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| 37. |
- Franzén, Lars, et al.
(författare)
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Fractionated irradiation and early changes in noradrenaline induced potassium efflux(86Rb+) in rat parotid gland
- 1992
-
Ingår i: Acta Oncologica. - 0284-186X .- 1651-226X. ; 31:3, s. 359-364
-
Tidskriftsartikel (refereegranskat)abstract
- The effects of fractionated irradiation on the electrolyte fluid secretion from rat parotid gland were studied. Secretion was measured as noradrenaline stimulated potassium efflux in vitro with Rb-86+ as tracer for potassium. The irradiation was delivered either as a five-day schedule (total dose 20, 25, 30, 35, 40, 45 Gy) or a two-day schedule (total dose 24, 32 Gy). The noradrenaline stimulated efflux was decreased in comparison with contralateral controls 10 days after the last irradiation. The effect was dose-dependent. Based on the data available, alpha/beta ratio of the used system was calculated to about 20 Gy, which corresponds to other results regarding early radiation effects.
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| 38. |
- Franzén, Lars, et al.
(författare)
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Fractionated-irradiation and late changes in rat parotid-gland : effects on the number of acinar-cells, potassium efflux, and amylase secretion
- 1993
-
Ingår i: International Journal of Radiation Biology. - : Informa UK Limited. - 0955-3002 .- 1362-3095. ; 64:1, s. 93-101
-
Tidskriftsartikel (refereegranskat)abstract
- Irradiation of head- and neck cancer commonly results in oral dryness and discomfort for the patients due to salivary gland damage. The exact mechanisms behind the inherent radiosensitivity of salivary glands remain to be elucidated. In the present study, we used different in vitro secretory models and quantitative morphological characterization of rat parotid gland following fractionated unilateral irradiation to one gland on a 5-day fraction schedule (Monday-Friday) with 6 MV photons (total dose 30, 35, 40 and 45 Gy) or a two-fractions regimen in 5 days (Monday and Friday) with total dose of 24 and 32 Gy. The contralateral shielded gland served as control, and parallel analyses of irradiated and control glands were performed 180 days following the last irradiation treatment. The relative noradrenaline stimulated electrolyte secretion (rubidium-86 tracer for potassium) was decreased in the irradiated compared with control glands. The noradrenaline-stimulated exocytotic amylase release was not significantly affected by irradiation, but the gland content of amylase was decreased dose-dependently. The quantitative morphological analysis revealed a dose-dependent decline in the number of acinar cells, whereas the other parenchymal cells (intercalated, striated- and excretory duct cells) were un-, affected by the irradiation compared with control glands.
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| 39. |
- Gad, Helge, et al.
(författare)
-
MTH1 inhibition eradicates cancer by preventing sanitation of the dNTP pool
- 2014
-
Ingår i: Nature. - : Nature Publishing Group. - 0028-0836 .- 1476-4687. ; 508:7495, s. 215-221
-
Tidskriftsartikel (refereegranskat)abstract
- Cancers have dysfunctional redox regulation resulting in reactive oxygen species production, damaging both DNA and free dNTPs. The MTH1 protein sanitizes oxidized dNTP pools to prevent incorporation of damaged bases during DNA replication. Although MTH1 is non-essential in normal cells, we show that cancer cells require MTH1 activity to avoid incorporation of oxidized dNTPs, resulting in DNA damage and cell death. We validate MTH1 as an anticancer target in vivo and describe small molecules TH287 and TH588 as first-in-class nudix hydrolase family inhibitors that potently and selectively engage and inhibit the MTH1 protein in cells. Protein co-crystal structures demonstrate that the inhibitors bindin the active site of MTH1. The inhibitors cause incorporation of oxidized dNTPs in cancer cells, leading to DNA damage, cytotoxicity and therapeutic responses in patient-derived mouse xenografts. This study exemplifies the non-oncogene addiction concept for anticancer treatment and validates MTH1 as being cancer phenotypic lethal.
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| 40. |
- Giummarella, Nicola, et al.
(författare)
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Lignin Prepared by Ultrafiltration of Black Liquor : Investigation of Solubility, Viscosity, and Ash Content
- 2016
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Ingår i: BioResources. - : North Carolina State University. - 1930-2126. ; 11:2, s. 3494-3510
-
Tidskriftsartikel (refereegranskat)abstract
- Technical lignin, which can be potentially obtained in large amounts as a by-product from kraft pulping, represents a potential resource for manufacturing fuels and chemicals. Upgrading of lignin, by lowering its molecular weight, is a valuable alternative to precipitation from black liquor, which occurs in the Lignoboost process. The solubility properties of Lignoboost lignin and filtered lignin in a number of technically feasible solvents were compared, and it was found that both lignins were dissolved in similar solvents. With the exception of furfural, the best lignin solvents generally were organic solvents miscible with water, such as methanol. It was possible to dissolve more filtered lignin in higher concentrations than Lignoboost lignin; additionally, the viscosities of the filtered lignin solutions were also considerably lower than those of Lignoboost lignin, especially at higher concentrations. Methods for non-organic component removal from filtrated lignin were tested, and it was concluded that several cold acidic treatments after dewatering can lower the ash content to values below 0.5% by weight.
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| 41. |
- Gruber, Hans, 1983, et al.
(författare)
-
Effect of Powder Recycling in Electron Beam Melting on the Surface Chemistry of Alloy 718 Powder
- 2019
-
Ingår i: Metallurgical and Materials Transactions A: Physical Metallurgy and Materials Science. - : Springer Science and Business Media LLC. - 1073-5623. ; 50:9, s. 4410-4422
-
Tidskriftsartikel (refereegranskat)abstract
- Process-induced degradation of the powder feedstock in additive manufacturing may have a negative influence on the final properties of built components. Consequently, it may lower the cost-effectiveness of powder bed additive manufacturing, which relies on recycling of the nonconsumed powder. This is especially the case for production of high-performance aero engine components where high material and process reliability is required. This study comprises a detailed investigation on the degradation of Alloy 718 powder during multicycle electron beam melting (EBM). The surface-sensitive analysis methods, X-ray photoelectron spectroscopy (XPS) and Auger electron spectroscopy (AES), were combined with scanning electron microscopy (SEM) to depict the differences in surface morphology, and surface composition of powder samples exposed to varying numbers of re-use cycles. The results show a significant change in surface characteristics after exposing the powder to the process and the environment in the build chamber. The virgin powder is covered mainly by a relatively thin and homogeneous oxide layer. The re-used powder, however, has undergone transformation to a heterogeneous oxide layer, rich in thermodynamically stable Al-rich oxide particulates, which started already during the first build cycle. Significant growth of the Al-rich oxide occurs via selective oxidation of Al under the conditions in the build chamber, including both pick-up of oxygen from the process atmosphere and redistribution of initial surface-bound oxygen from less-stable products like Ni-oxide and/or hydroxide.
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| 42. |
- Gruneau, Lina, 1994-, et al.
(författare)
-
Precision i hälsoekonomiska utvärderingsresultat och osäkerhet i prioriteringsbeslut
- 2022
-
Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Tandvårds- och läkemedelsförmånsverket (TLV) genomför på uppdrag av regeringen ett arbete med att utveckla metoder för hälsoekonomiska utvärderingar av precisionsmedicin och betalningsmodeller för avancerade terapiläkemedel (ATMP). TLV redovisar i sin andra rapport inom ramen för uppdraget ett antal nya möjliga metoder som kan användas i en hälsoekonomisk utvärdering för att värdera huruvida de priser som företagen efterfrågar är rimliga i förhållande till läkemedlens nytta. Eftersom hälsoekonomiska utvärderingar alltid är behäftade med osäkerhet i skattningarna är frågan om hur osäkerhet skall analyseras och beskrivas central för precisionsmedicin och ATMP då dataunderlagen ofta är knapphändiga. I en slutsats från ett tidigare arbete om utmaningarna med att utvärdera kostnader och hälsoeffekter inom ramen för precisionsmedicin konstaterades det att osäkerheten i skattningarna av kostnadseffektivitet kommer att öka när patientpopulationerna som utvärderas blir allt mindre. Vidare framgick det i de tidigare arbetena att TLVs ansats för att beskriva och analysera osäkerhet inte alltid är helt tydlig. Som en del i TLVs regeringsuppdrag ingår det att beskriva och tydliggöra osäkerheter i skattningar av kostnadseffektivitet samt hur dessa osäkerhet kan påverka osäkerhet i prioriteringsbeslut och den här rapporten är en del i det arbetet.Rapporten är fristående från den rapport som TLV skrivit inom ramen för regeringsuppdraget men har som mål att ge en kompletterande beskrivning av de osäkerheter som oftast föreligger när hälsoekonomiska utvärderingar utgör en del av ett underlag för prioriteringsbeslut. Förhoppningen är att denna rapport tillsammans med TLVs rapport ska stimulera till fortsatt diskussion om potentiella lösningar för att hantera utmaningar inte bara med precisionsmedicin och ATMP utan även med beslutsfattande under osäkerhet generellt inom hälso- och sjukvården.
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| 43. |
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| 44. |
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| 45. |
- Hansson, Martin, et al.
(författare)
-
Björketorpstenen, Vång och en helig förbannelse
- 2016
-
Ingår i: Vikten av Vång : en järnåldersplats tar form - en järnåldersplats tar form. - 9789198259827 ; , s. 23-32
-
Bokkapitel (populärvet., debatt m.m.)
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| 46. |
- Hansson, Martin, et al.
(författare)
-
Tornet vid havet - ledtrådar till historien bakom Hagbards källare
- 2022
-
Ingår i: Arkeologi i Blekinge. - 9789198346534 ; , s. 49-51
-
Bokkapitel (populärvet., debatt m.m.)abstract
- Strax sydöst om Ronneby i anslutning till Angelåns utlopp i Angelskogsviken, öster om Ronnebyhamn , ligger en anläggning som i folkmun kallas ”Hagbards källare”. Det utgör resterna av ett medeltida torn. Artikeln berättar om de preliminära resultaten av en arkeologisk undersökning 2021.
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| 47. |
- Heinonen, Emilia, et al.
(författare)
-
Xylan adsorption on cellulose : Preferred alignment and local surface immobilizing effect
- 2022
-
Ingår i: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 285, s. 119221-119221
-
Tidskriftsartikel (refereegranskat)abstract
- Interaction between xylan and cellulose microfibrils is required to maintain the integrity of secondary cell walls. However, the mechanisms governing their assembly and the effects on cellulose surface polymers are not fully clear. Here, molecular dynamics simulations are used to study xylan adsorption onto hydrated cellulose fibrils. Based on multiple spontaneous adsorption simulations it is shown that an antiparallel orientation is thermodynamically preferred over a parallel one, and that adsorption is accompanied by the formation of regular but orientation-dependent hydrogen bond patterns. Furthermore, xylan adsorption restricts the local dynamics of the adjacent glucose residues in the surface layer to a level of the crystalline core, which is manifested as a three-fold increase in their 13C NMR T1 relaxation time. These results suggest that xylan forms a rigid and ordered layer around the cellulose fibril that functions as a transition phase to more flexible and disordered polysaccharide and lignin domains.
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| 48. |
- Helander, Mikaela, et al.
(författare)
-
Fractionation of Technical Lignin: Molecular Mass and pH Effects
- 2013
-
Ingår i: BioResources. - : BioResources. - 1930-2126 .- 1930-2126. ; 8:2, s. 2270-2282
-
Tidskriftsartikel (refereegranskat)abstract
- Today, lignin from kraft pulping is used mainly as fuel, with only very small amounts being used as raw material for chemicals and materials. This work focuses on using a convenient method for separating large amounts of low molecular weight lignin from the kraft process. Low molecular weight lignin contains larger amounts of phenolic structural units, which are possible modification sites and can be used as antioxidants. Moreover, a product that has reduced polydispersity, low molecular weight, and purified lignin could be a potential material for new applications. The studied process for separating lignin from weak black liquor used a membrane with a cut-off of 1000 Da. During precipitation of the 1000 Da permeate, it is necessary to prevent formation of fairly large, rigid particles/agglomerates of lignin by keeping the temperature low. To improve the dead-end filtration, higher ionic strength is needed for the weak black liquor. Additionally, reducing the end pH will cause more material to precipitate. More sulfur was found in the low molecular weight lignin and at lower precipitation pH, indicating that most sulfur left in the lignin samples might be bound to low molecular weight lignin.
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| 49. |
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| 50. |
- Henriksson, Emma, et al.
(författare)
-
SIK2 regulates CRTCs, HDAC4 and glucose uptake in adipocytes
- 2015
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Ingår i: Journal of Cell Science. - : The Company of Biologists. - 0021-9533 .- 1477-9137. ; 128:3, s. 472-486
-
Tidskriftsartikel (refereegranskat)abstract
- Salt-inducible kinase 2 (SIK2) is an AMP-activated protein kinase (AMPK) related kinase abundantly expressed in adipose tissue. Our aim was to identify molecular targets and functions of SIK2 in adipocytes, and to address the role of PKA-mediated phosphorylation of SIK2 on Ser358. Modulation of SIK2 in adipocytes resulted in altered phosphorylation of CREB-regulated transcription co-activator 2 (CRTC2), CRTC3 and class IIa histone deacetylase 4 (HDAC4). Furthermore, CRTC2, CRTC3, HDAC4 and protein phosphatase 2A (PP2A) interacted with SIK2, and the binding of CRTCs and PP2A to wild-type but not Ser358Ala SIK2, was reduced by cAMP elevation. Silencing of SIK2 resulted in reduced GLUT4 (also known as SLC2A4) protein levels, whereas cells treated with CRTC2 or HDAC4 siRNA displayed increased levels of GLUT4. Overexpression or pharmacological inhibition of SIK2 resulted in increased and decreased glucose uptake, respectively. We also describe a SIK2-CRTC2-HDAC4 pathway and its regulation in human adipocytes, strengthening the physiological relevance of our findings. Collectively, we demonstrate that SIK2 acts directly on CRTC2, CRTC3 and HDAC4, and that the cAMP-PKA pathway reduces the interaction of SIK2 with CRTCs and PP2A. Downstream, SIK2 increases GLUT4 levels and glucose uptake in adipocytes.
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