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1.	Kehoe, Laura, et al. (författare) Make EU trade with Brazil sustainable 2019 Ingår i: Science. - : American Association for the Advancement of Science (AAAS). - 0036-8075 .- 1095-9203. ; 364:6438, s. 341- Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
2.	Andersson, Christian, et al. (författare) Utredning om funktions- och leveranskontroller av radiologisk utrustning : För röntgendiagnostik och interventioner 2016 Rapport (övrigt vetenskapligt/konstnärligt)
3.	Arlien-Soborg, Mai C., et al. (författare) Acromegaly management in the Nordic countries: A Delphi consensus survey 2024 Ingår i: CLINICAL ENDOCRINOLOGY. - : WILEY. - 0300-0664 .- 1365-2265. Tidskriftsartikel (refereegranskat)abstract ObjectiveAcromegaly is associated with increased morbidity and mortality if left untreated. The therapeutic options include surgery, medical treatment, and radiotherapy. Several guidelines and recommendations on treatment algorithms and follow-up exist. However, not all recommendations are strictly evidence-based. To evaluate consensus on the treatment and follow-up of patients with acromegaly in the Nordic countries.MethodsA Delphi process was used to map the landscape of acromegaly management in Denmark, Sweden, Norway, Finland, and Iceland. An expert panel developed 37 statements on the treatment and follow-up of patients with acromegaly. Dedicated endocrinologists (n = 47) from the Nordic countries were invited to rate their extent of agreement with the statements, using a Likert-type scale (1-7). Consensus was defined as >= 80% of panelists rating their agreement as >= 5 or <= 3 on the Likert-type scale.ResultsConsensus was reached in 41% (15/37) of the statements. Panelists agreed that pituitary surgery remains first line treatment. There was general agreement to recommend first-generation somatostatin analog (SSA) treatment after failed surgery and to consider repeat surgery. In addition, there was agreement to recommend combination therapy with first-generation SSA and pegvisomant as second- or third-line treatment. In more than 50% of the statements, consensus was not achieved. Considerable disagreement existed regarding pegvisomant monotherapy, and treatment with pasireotide and dopamine agonists.ConclusionThis consensus exploration study on the management of patients with acromegaly in the Nordic countries revealed a relatively large degree of disagreement among experts, which mirrors the complexity of the disease and the shortage of evidence-based data.
4.	Auvray, Xavier, 1986, et al. (författare) The effect gas composition during thermal aging on the dispersion and NO oxidation activity over Pt/Al2O3 catalysts 2013 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 129, s. 517-527 Tidskriftsartikel (refereegranskat)abstract The aging of a model 1 wt.% Pt/Al2O3 catalyst was performed stepwise under different reactive atmosphere to study the evolution of metal dispersion and NO oxidation activity. After each aging step the dispersion was evaluated by CO chemisorptions and the activity of the catalyst for NO oxidation was measured using 500 ppm NO and 8%O-2 diluted in Ar. After a degreening step at 500 degrees C, aging was performed at 600, 700,800 and 900 degrees C. Five wash-coated cordierite monoliths were aged in Ar, 10% O-2, 1% H-2 30 ppm SO2 and 30 ppm SO2 + 10% O-2, respectively. The general trend showed a linear decrease in dispersion when increasing the aging temperature for the lower aging temperatures and for the highest ones the dispersion levels off. When the platinum dispersion decreased the NO oxidation activity increased, due to that the reaction is structure sensitive. H-2 seemed to hinder sintering at low aging temperature. Interestingly, after aging in 10% oxygen at 600 degrees C the NO oxidation activity was significantly higher compared to the Ar aged sample, although the dispersions were similar. Aging in oxygen at higher temperatures resulted in a decrease of dispersion and a slightly decreasing NO oxidation activity. Moreover lower dispersion limit was reached with oxygen aging. Aging in SO2 provoked a severe dispersion drop at low aging temperature meanwhile the activity increased only moderately. However, activity kept increasing with further treatments at higher temperature. The combination of O-2 and SO2 enabled to decrease rapidly the dispersion and to greatly enhance the catalytic NO oxidation activity after the first aging step at only 600 degrees C. The best overall conversion was obtained for the catalyst treated with this mixture after aging at 800 degrees C. A 22-h aging at 250 degrees C in a mixture containing 500 ppm NO, 10% O-2 and 30 ppm SO2 led to a significant decrease of Pt dispersion, which shows the ability of SO2 to promote platinum sintering already 250 degrees C. The low temperature sintering was confirmed with STEM measurements. Several larger particles were observed, but also many small particles remained. Thus the SO2 + O-2 induced low temperature sintering results in a large variation of particle sizes. This treatment resulted in an increase of the maximum NO conversion (after reduction of the sample) from 45% to 76%. The different aging experiments show that it is beneficial to add SO2 during aging and the reason is the increased particle size, but also a clear chemical effect was observed.
5.	Fortuin-de Smidt, Melony C., et al. (författare) Effect of exercise training on insulin sensitivity, hyperinsulinemia and ectopic fat in black South African women : a randomized controlled trial 2020 Ingår i: European Journal of Endocrinology. - : Bioscientifica. - 0804-4643 .- 1479-683X. ; 183:1, s. 51-61 Tidskriftsartikel (refereegranskat)abstract Objective: We investigated the effects of a 12-week exercise intervention on insulin sensitivity (SI) and hyperinsulinemia and associated changes in regional and ectopic fat.Research design and methods: Healthy, black South African women with obesity (mean age 23 ± 3.5 years) and of isiXhosa ancestry were randomised into a 12-week aerobic and resistance exercise training group (n = 23) and a no exercise group (control, n = 22). Pre and post-intervention testing included assessment of SI, insulin response to glucose (AIRg), insulin secretion rate (ISR), hepatic insulin extraction (FEL) and disposition index (DI) (AIRg × SI) (frequently sampled i.v. glucose tolerance test); fat mass and regional adiposity (dual-energy X-ray absorptiometry); hepatic, pancreatic and skeletal muscle fat content and abdominal s.c. and visceral adipose tissue volumes (MRI).Results: Exercise training increased VO2peak (mean ± s.d.: 24.9 ± 2.42 to 27.6 ± 3.39 mL/kg/min, P < 0.001), SI (2.0 (1.2–2.8) to 2.2 (1.5–3.7) (mU/l)−1 min−1, P = 0.005) and DI (median (interquartile range): 6.1 (3.6–7.1) to 6.5 (5.6–9.2) × 103 arbitrary units, P = 0.028), and decreased gynoid fat mass (18.5 ± 1.7 to 18.2 ± 1.6%, P < 0.001) and body weight (84.1 ± 8.7 to 83.3 ± .9.7 kg, P = 0.038). None of these changes were observed in the control group, but body weight increased (P = 0.030). AIRg, ISR and FEL, VAT, SAT and ectopic fat were unaltered after exercise training. The increase in SI and DI were not associated with changes in regional or ectopic fat.Conclusion: Exercise training increased SI independent from changes in hyperinsulinemia and ectopic fat, suggesting that ectopic fat might not be a principal determinant of insulin resistance in this cohort.
6.	Jonsson, Rasmus, 1989, et al. (författare) Chemical poisoning by zinc and phosphorous of Pt/Ba/Al2O3 NOx storage catalysts 2019 Ingår i: Applied Catalysis A: General. - : Elsevier BV. - 1873-3875 .- 0926-860X. ; 571, s. 158-169 Tidskriftsartikel (refereegranskat)abstract The effects of phosphorous and zinc on the performance of Pt/Ba/Al2O3 catalysts were investigated through wet impregnation of ammonium phosphate and zinc acetate aqueous solutions. Six different sample combinations were studied; 1 wt-% P, 1 wt-% Zn, 1 wt-% P with 1 wt-% Zn, 2 wt-% P, 2 wt-% Zn, 2 wt-% P with 2 wt-% Zn. NOx storage and reduction (NSR) activity and NO2 temperature programmed desorption (TPD) profiles were measured before and after impregnation of P and Zn. Samples containing P performed significantly worse than samples only containing Zn in both NSR activity and TPD measurements. The increased NOx slip during lean phase in activity measurements for P-poisoned samples is mainly related to an increased slip of NO2. This was found for both NO and NO2 in the gas feed during lean phase and suggests that it is mainly the storage component that is poisoned and not the noble metal. Furthermore, the combination (1 wt-% P and 1 wt-% Zn) proved to result in slightly worse performance than only 1 wt-% P, however this was not the case for samples containing 2 wt-%, where the addition of zinc reduced the negative effect of phosphorous. Measurements from NO2-TPD experiments showed that NOx release at low temperature was not affected by the addition of P, while desorption in the temperature range 425–475 °C was significantly reduced. It can therefore be concluded that the poisoning mainly is related to barium NOx storage sites and not to alumina sites. Moreover, X-ray diffraction measurements indicate that some of the barium species are affected by phosphorous. Images from scanning transmission electron microscopy (STEM) and energy-dispersive X-ray spectroscopy (EDX) mapping were in line with the results seen in both the activity tests and NO2-TPD experiments. Phosphorous was concentrated at the same position as barium in the observed images, whereas zinc was more evenly distributed over the surface. For the sample with both 2 wt-% P and 2 wt-% Zn, X-ray photoelectron spectroscopy measurements indicate that Zn and P have a low interaction and this suggests that most of the zinc and phosphorous are separated. However, STEM-EDX showed agglomerates of some zinc and phosphorous, which could be zinc phosphates. This is a plausible explanation of the decreased deactivation observed after introducing 2 wt-% Zn compared to the sample only containing 2 wt-% P.
7.	Jonsson, Rasmus, 1989, et al. (författare) Gas-phase phosphorous poisoning of a Pt/Ba/Al2O3 NOx storage catalyst 2018 Ingår i: Catalysts. - : MDPI AG. - 2073-4344. ; 8:4 Tidskriftsartikel (refereegranskat)abstract The effect of phosphorous exposure on the NO x storage capacity of a Pt/Ba/Al 2 O 3 catalyst coated on a ceramic monolith substrate has been studied. The catalyst was exposed to phosphorous by evaporating phosphoric acid in presence of H 2 O and O 2 . The NOx storage capacity was measured before and after the phosphorus exposure and a significant loss of the NO x storage capacity was detected after phosphorous exposure. The phosphorous poisoned samples were characterized by X-ray photoelectron spectroscopy (XPS), environmental scanning electron microscopy (ESEM), N 2 -physisorption and inductive coupled plasma atomic emission spectroscopy (ICP-AES). All characterization methods showed an axial distribution of phosphorous ranging from the inlet to the outlet of the coated monolith samples with a higher concentration at the inlet of the samples. Elemental analysis, using ICP-AES, confirmed this distribution of phosphorous on the catalyst surface. The specific surface area and pore volume were significantly lower at the inlet section of the monolith where the phosphorous concentration was higher, and higher at the outlet where the phosphorous concentration was lower. The results from the XPS and scanning electron microscopy (SEM)-energy dispersive X-ray (EDX) analyses showed higher accumulation of phosphorus towards the surface of the catalyst at the inlet of the monolith and the phosphorus was to a large extent present in the form of P 4 O 10 . However, in the middle section of the monolith, the XPS analysis revealed the presence of more metaphosphate (PO 3 – ). Moreover, the SEM-EDX analysis showed that the phosphorous to higher extent had diffused into the washcoat and was less accumulated at the surface close to the outlet of the sample
8.	Olofsson, Louise, 1977, et al. (författare) CCAAT/enhancer binding protein alpha (C/EBPalpha) in adipose tissue regulates genes in lipid and glucose metabolism and a genetic variation in C/EBPalpha is associated with serum levels of triglycerides. 2008 Ingår i: The Journal of clinical endocrinology and metabolism. - : The Endocrine Society. - 0021-972X .- 1945-7197. ; 93:12, s. 4880-6 Tidskriftsartikel (refereegranskat)abstract CONTEXT: CCAAT/enhancer binding protein alpha (C/EBPalpha) is a transcription factor involved in adipogenesis and hepatic glucose and lipid metabolism. OBJECTIVE: The aim of the study was to test the hypothesis that adipose tissue C/EBPalpha regulates genes in lipid and glucose metabolism and to test for an association between a polymorphism in C/EBPalpha and metabolic parameters. DESIGN AND METHODS: Adipose tissue C/EBPalpha mRNA expression was analyzed at four time points in obese subjects with (n = 12) and without (n = 12) the metabolic syndrome during caloric restriction (450 kcal/d for 16 wk) using DNA microarray and real-time PCR. Adenoviral overexpression of C/EBPalpha was used to identify genes regulated by C/EBPalpha in 3T3-L1 cells. Association between a genetic variation in C/EBPalpha (rs12691) and metabolic parameters was tested in the Swedish Obese Subjects (SOS) study (n = 528) and replicated in Finnish individuals from the Botnia type 2 diabetes study (n = 4,866). RESULTS: During caloric restriction, adipose tissue C/EBPalpha mRNA levels were reduced in subjects with the metabolic syndrome (P = 0.024) and correlated to metabolic parameters. In 3T3-L1 cells, C/EBPalpha regulated the expression of adiponectin; hexokinase 2; lipoprotein lipase; diacylglycerol O-acyltransferase 1 and 2; ATP-binding cassette, sub-family D, member 2; acyl-coenzyme A synthetase long-chain family member 1; CD36; and hydroxysteroid 11-beta dehydrogenase 1. Furthermore, the expression of the human homologs, except adiponectin, correlated to C/EBPalpha mRNA levels in human adipose tissue. The AA genotype of rs12691 was associated with higher serum triglyceride levels in the SOS study (P = 0.022), and this association was replicated in the Botnia study (P = 0.041). CONCLUSIONS: Adipose tissue C/EBPalpha regulates several genes in glucose and lipid metabolism, and a genetic variation in C/EBPalpha is associated with triglycerides in two independent populations.
9.	Olsson Månsson, Emma, 1992, et al. (författare) Removal of Inorganic Impurities in the Fast Pyrolysis Bio-oil Using Sorbents at Ambient Temperature 2024 Ingår i: Energy & Fuels. - 1520-5029 .- 0887-0624. ; 38:1, s. 414-4254 Tidskriftsartikel (refereegranskat)abstract Fast pyrolysis bio-oil (FPBO) sourced from residual biomass waste (such as sawdust) is a promising feedstock that may be used for biofuel production. Their inorganic elements may, however, vary and cause deactivation of the catalysts in the hydrodeoxygenation (HDO) upgrading biorefinery unit. It was found that the use of zeolite Y and strong acidic ion-exchange resins as adsorbents was almost equally efficient in lowering the concentrations of Ca from <10 to <1 ppm and of Fe, K, and Mg to <0.3 ppm in FPBO at 30 °C, atmospheric pressure, and 4 h adsorption time. The removal efficiency of zeolite and resins exceeded 85–98% (detection limit) of these particular elements. For the first time for the FPBO, phosphorus was reported as being successfully targeted by aluminum oxide, being lowered from 1 ppm to <0.1 ppm, which is a reduction of at least 90%. Characterization of the oil and sorbents suggests that the surface acidity affects the removal efficiency of these elements from FPBO. Organic compounds in the pyrolysis oil, including isopropanol, lactic acid, hydroxy acetone, furfural, guaiacol, and levoglucosan, were semiquantified using two-dimensional gas chromatography coupled with mass spectrometry (GCxGC-MS). Compared to the fresh oil, the compositions and contents of these organic compounds were not impacted significantly by the sorbents under these mild operating conditions. This research indicates that inorganic impurities present in bio-oils can be removed, and thus, they may be considered feedstocks for producing biofuels with less deactivation of HDO catalysts.
10.	Achour, Abdenour, 1980, et al. (författare) Evaluation of kraft and hydrolysis lignin hydroconversion over unsupported NiMoS catalyst 2023 Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947. ; 453 Tidskriftsartikel (refereegranskat)abstract Catalytic hydroconversion of Kraft and hydrolysis lignins was for the first time compared in a batch reactor over an unsupported NiMoS-SBA catalyst. We also report the effect of key reaction parameters on the yields and properties of the products. The results obtained at 20 wt% catalyst loading for hydrolysis lignin showed the highest monomer yield of 76.0 wt%, which consisted of 39 wt% aromatics with the lowest alkylphenolics yield of 10.1 wt%. Identical operating conditions, 400 °C, 80 bar, 5 h at 10 wt% catalyst loading, were used to compare both lignins and the highest monomer yield (64.3 wt%) was found for the hydrolysis lignin, consisting of 16.0 wt% alkylphenolics and 20.1 wt% aromatic compounds. These values are considerably higher than those for Kraft lignin with its 47.0 wt% monomer yield. We suggest that the reason for high yields of monomeric units from hydrolysis lignin is that it is more reactive due to its lower ash and sulfur contents and the chemical structural differences compared to the Kraft lignin. More precisely, the bio-oil from hydrolysis lignin contained higher yields of small molecules, sourced from ring-opening of cellulose in the hydrolysis lignin, which could stabilize the reactive oligomeric groups. These yields were two to seven times higher from kraft and hydrolysis lignin, respectively, compared to those obtained without catalyst. The results showed that the NiMoS-SBA catalyst is a promising catalyst for reductive depolymerization of lignin and in addition that the regenerated catalyst had good stability for multiple reaction cycles.
11.	Achour, Abdenour, 1980, et al. (författare) Towards stable nickel catalysts for selective hydrogenation of biomass-based BHMF into THFDM 2023 Ingår i: Journal of Environmental Chemical Engineering. - : Elsevier BV. - 2213-3437 .- 2213-2929. ; 11:2 Tidskriftsartikel (refereegranskat)abstract Selective transformation of BHMF (2,5-bis(hydroxymethyl)furan) to THFDM (tetrahydrofuran-2,5-dimethanol) over a variety of structured Ni/Sx-Z1−x catalysts was investigated. The effects of support, Ni loading, solvent, temperature, pressure, and particle size on the conversion and selectivity were studied. Among them, the 10 wt% Ni catalyst supported on the SiO2:ZrO2 weight ratio of 90:10 (10NiS90Z10) exhibits the best performance in terms of BHMF conversion and THFDM selectivity. Its good performance was attributed to its well-balanced properties, that depend upon the ZrO2 content of the support in combination with SiO2, the active Ni sites-support interaction, and acidity/basicity ratio of each catalyst resulting in different Ni dispersions. Importantly, the 10NiS90Z10 catalyst showed a stable selectivity to THFDM (>94%), with 99.4% conversion of BHMF during 2 h reaction time. Poor catalytic activity resulted from excessive ZrO2 content (>10 wt%). The structural, textural, and acidity properties of NiSi100−y-Zry catalysts, tuned by selectively varying the Ni amount from 5 to 15 wt%, were critically investigated using numerous material characterization techniques. Catalyst recycling experiments revealed that the catalyst could be recycled several times without any measurable loss of catalytic activity.
12.	Adermark, Louise, 1974, et al. (författare) Ethanol acutely decreases astroglial gap junction permeability in primary cultures from defined brain regions 2004 Ingår i: Neurochemistry International. - : Elsevier BV. - 0197-0186. ; 45:7, s. 971-978 Tidskriftsartikel (refereegranskat)abstract The acute effect of hyperosmotic ethanol on gap junction permeability was examined in astroglial cells in primary culture from five different brain regions. Gap junction permeability was analyzed by measuring dye spreading from cell to cell with the low molecular weight dye Lucifer Yellow. Ethanol concentrations 25-300 mM significantly decreased dye spreading in cultures from the cerebral cortex in a dose-dependent but time-independent manner for up to 60 min. Besides cerebral cortex, exposure to 150 mM ethanol decreased dye spreading in astroglial cultures from the hippocampus and from the brain stem, while cultures from the olfactory bulb and from the hypothalamus were not significantly affected. The ethanol-induced decrease in dye spreading in cultures from the cerebral cortex was not mediated through changes in cell volume, osmolarity, protein kinase C (PKC) phosphorylation, intracellular pH, or intracellular calcium concentration ([Ca 2+ ] i ). The decrease in dye spreading was abolished upon incubation in sodium-reduced buffer, and after blockage of the Na + /K + /2Cl - cotransporter with furosemide. The results presented here indicate that ethanol-mediated decrease in dye spreading is directly or indirectly dependent on sodium. © 2004 Elsevier Ltd. All rights reserved.
13.	Adermark, Louise, 1974, et al. (författare) Implications for glycine receptors and astrocytes in ethanol-induced elevation of dopamine levels in the nucleus accumbens. 2011 Ingår i: Addiction biology. - : Wiley. - 1369-1600 .- 1355-6215. ; 16:1, s. 43-54 Tidskriftsartikel (refereegranskat)abstract ABSTRACT Elevated dopamine levels are believed to contribute to the rewarding sensation of ethanol (EtOH), and previous research has shown that strychnine-sensitive glycine receptors in the nucleus accumbens (nAc) are involved in regulating dopamine release and in mediating the reinforcing effects of EtOH. Furthermore, the osmoregulator taurine, which is released from astrocytes treated with EtOH, can act as an endogenous ligand for the glycine receptor, and increase extracellular dopamine levels. The aim of this study was to address if EtOH-induced swelling of astrocytes could contribute to elevated dopamine levels by increasing the extracellular concentration of taurine. Cell swelling was estimated by optical sectioning of fluorescently labeled astrocytes in primary cultures from rat, and showed that EtOH (25-150 mM) increased astrocyte cell volumes in a concentration- and ion-dependent manner. The EtOH-induced cell swelling was inhibited in cultures treated with the Na(+)/K(+)/2Cl(-) cotransporter blocker furosemide (1 mM), Na(+)/K(+)-ATPase inhibitor ouabain (0.1 mM), potassium channel inhibitor BaCl(2) (50 microM) and in cultures containing low extracellular sodium concentration (3 mM). In vivo microdialysis performed in the nAc of awake and freely moving rats showed that local treatment with EtOH enhanced the concentrations of dopamine and taurine in the microdialysate, while glycine and beta-alanine levels were not significantly modulated. EtOH-induced dopamine release was antagonized by local treatment with the glycine receptor antagonist strychnine (20 microM) or furosemide (100 microM or 1 mM). Furosemide also prevented EtOH-induced taurine release in the nAc. In conclusion, our data suggest that extracellular concentrations of dopamine and taurine are interconnected and that swelling of astrocytes contributes to the acute rewarding sensation of EtOH.
14.	Ahlberg, Erik, et al. (författare) "Vi klimatforskare stödjer Greta och skolungdomarna" 2019 Ingår i: Dagens nyheter (DN debatt). - 1101-2447. Tidskriftsartikel (populärvet., debatt m.m.)abstract DN DEBATT 15/3. Sedan industrialiseringens början har vi använt omkring fyra femtedelar av den mängd fossilt kol som får förbrännas för att vi ska klara Parisavtalet. Vi har bara en femtedel kvar och det är bråttom att kraftigt reducera utsläppen. Det har Greta Thunberg och de strejkande ungdomarna förstått. Därför stödjer vi deras krav, skriver 270 klimatforskare.
15.	Ali, Haytham, et al. (författare) Utility of G protein-coupled receptor 35 expression for predicting outcome in colon cancer 2019 Ingår i: Tumor Biology. - : Sage Publications. - 1010-4283 .- 1423-0380. ; 41:6 Tidskriftsartikel (refereegranskat)abstract The utility of mRNA and protein determinations of G protein-coupled receptor 35, that is, GPR35a (GPR35 V1) and GPR35b (GPR35 V2/3), as indicators of outcome for colon cancer patients after curative surgery was investigated. Expression levels of V1 and V2/3 GPR35, carcinoembryonic antigen and CXCL17 mRNAs were assessed in primary tumours and regional lymph nodes of 121 colon cancer patients (stage I–IV), colon cancer cell lines and control colon epithelial cells using real-time quantitative reverse transcriptase-polymerase chain reaction. Expression of G protein-coupled receptor 35 was investigated by two-colour immunohistochemistry and immunomorphometry. GPR35 V2/3 mRNA, but not V1 mRNA, was expressed in colon cancer cell lines, primary colon tumours and control colon epithelial cells. Haematoxylin and eosin positive (H&E(+)), but not H&E(–), lymph nodes expressed high levels of GPR35 V2/3 mRNA (P<0.0001). GPR35b and carcinoembryonic antigen proteins were simultaneously expressed in many colon cancer tumour cells. Kaplan–Meier and hazard ratio analysis revealed that patients with lymph nodes expressing high levels of GPR35 V2/3 mRNA and, in particular, in the group of patients with lymph nodes also expressing carcinoembryonic antigen mRNA, had a short disease-free survival time, 67 months versus 122 months at 12-year follow-up (difference: 55 months, P = 0.001; hazard ratio: 3.6, P = 0.002). In conclusion, high level expression of G protein-coupled receptor 35 V2/3 mRNA in regional lymph nodes of colon cancer patients is a sign of poor prognosis.
16.	Amberntsson, Annika, 1974, et al. (författare) Platinum oxidation and sulphur deactivation in NOx storage catalysts 2003 Ingår i: 6th International Congress on Catalysis and Automotive Pollution Control (CAPoC6), Brussels, Belgium, October 22-24, 2003. Konferensbidrag (refereegranskat)
17.	Ander, Malin, 1983-, et al. (författare) U-CARE: UngaKan : Ett internet-administrerat guidat självhjälsprogram för unga som diagnosticerats med cancer under tonåren 2017 Annan publikation (populärvet., debatt m.m.)
18.	Andersson, Anna, et al. (författare) Lactate contributes to ammonia-mediated astroglial dysfunction during hyperammonemia. 2009 Ingår i: Neurochemical research. - : Springer Science and Business Media LLC. - 1573-6903 .- 0364-3190. ; 34:3, s. 556-65 Tidskriftsartikel (refereegranskat)abstract Even though ammonia is considered to underlie nervous system symptoms of dysfunction during hyperammonemia, lactate, which increases as a metabolic consequence of high ammonia levels, might also be a contributing factor. The data presented here show that NH4Cl (5 mM) mediates astroglial cell swelling, and that treatment with NH4Cl or lactate (25 mM) causes rearrangements of actin filaments and reduces astroglial glutamate uptake capacity. Co-application with BaCl2, which blocks astroglial uptake of NH4+, prevents NH4Cl-mediated cell swelling and rearrangement of actin filaments, but does not reduce NH4Cl-induced glutamate uptake capacity inhibition. Neither NH4Cl nor lactate affected glutamate uptake or protein expression in microglial cultures, indicating that astroglial cells are more susceptible to the neurotoxic affects of ammonia. Our results suggest that ammonium underlies brain edema, but that lactate can contribute to some of the cellular dysfunctions associated with elevated cerebral levels of ammonia.
19.	Andersson, Claes, et al. (författare) Interactive voice response with feedback intervention in out-patient treatment of substance use problems in adolescents: a randomized controlled trial on substance use, stress and psychiatric symptoms. 2017 Ingår i: International Journal of Behavioral Medicine. - : Springer Science and Business Media LLC. - 1070-5503 .- 1532-7558. ; 24:5, s. 789-797 Tidskriftsartikel (refereegranskat)abstract Purpose: Substance use disorders and problematic substance use are common problems in adolescence and young adulthood. Brief personalized feedback has been suggested for treatment of alcohol and drug problems and poor mental health. This repeated measurement randomized controlled trial examines the effect of an interactive voice response (IVR) system for assessing stress, depression, anxiety and substance use. Methods: The IVR system was used twice weekly over 3 months after treatment initiation, with or without addition of a personalized feedback intervention on stress and mental health symptoms. Both IVR assessment only (control group) and IVR assessment including feedback (intervention group) were provided as an add-on to treatment-as-usual procedures (TAU) in outpatient treatment of substance use problems in adolescents and young adults (N = 73). Results: By using a mixed models approach, differences in change scores were analyzed over the three-month assessment period. Compared to the control group, the intervention group demonstrated significantly greater improvement in the Arnetz and Hasson stress score (AHSS, p = 0.019), the total Symptoms Checklist 8 score (SCL-8D, p = 0.037), the SCL-8D anxiety sub-score (p = 0.017), and on a summarized feedback score (p = 0.026), but not on the depression subscale. There were no differences in global substance use scores between the intervention group (feedback on mental health symptoms) and the control group. Conclusion: In conclusion, IVR may be useful for follow-up and repeated interventions as an add-on to regular treatment, and personalized feedback could potentially improve mental health in adolescents and young adults with problematic substance use.
20.	Andersson, Claes, et al. (författare) Interactive Voice Response with Feedback Intervention in Outpatient Treatment of Substance Use Problems in Adolescents and Young Adults : A Randomized Controlled Trial 2017 Ingår i: International Journal of Behavioral Medicine. - : Springer. - 1070-5503 .- 1532-7558. ; 24:5, s. 789-797 Tidskriftsartikel (refereegranskat)abstract Substance use disorders and problematic substance use are common problems in adolescence and young adulthood. Brief personalized feedback has been suggested for treatment of alcohol and drug problems and poor mental health. This repeated measurement randomized controlled trial examines the effect of an Interactive Voice Response (IVR) system for assessing stress, depression, anxiety and substance use. The IVR system was used twice weekly over three months after treatment initiation, with or without addition of a personalized feedback intervention on stress and mental health symptoms. Both IVR assessment only (control group) and IVR assessment including feedback (intervention group) were provided as an add-on to treatment-as-usual procedures (TAU) in outpatient treatment of substance use problems in adolescents and young adults (N=73). By using a mixed models approach, differences in change scores were analyzed over the three-month assessment period. Compared to the control group, the intervention group demonstrated significantly greater improvement in the Arnetz and Hasson stress score (AHSS, p=0.019), the total Symptoms Checklist 8 score (SCL-8D, p=0.037), the SCL-8D anxiety sub-score (p=0.017), and on a summarized feedback score (p=0.026), but not on the depression subscale. There were no differences in global substance use scores between the intervention group (feedback on mental health symptoms) and the control group. In conclusion, IVR may be useful for follow-up and repeated interventions as an add-on to regular treatment, and personalized feedback could potentially improve mental health in adolescents and young adults with problematic substance use.
21.	Andersson, Christer, et al. (författare) Manifest för lämplig styrning av hälso- och sjukvården 2018 Ingår i: Läkartidningen. - 0023-7205. ; 115:3 Tidskriftsartikel (refereegranskat)
22.	Andonova, Stanislava, 1977, et al. (författare) Chemical deactivation by phosphorous under lean hydrothermal conditions over Cu/BEA NH3-SCR catalysts 2014 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 147, s. 251-263 Tidskriftsartikel (refereegranskat)abstract To obtain a better understanding of the deactivation of SCR catalysts that may be encountered due to the presence of P-containing impurities in diesel exhausts, the effects induced by P over Cu/BEA NH3-SCR catalysts were studied as functions of the temperature of poisoning and P concentration in the feed. Cu/BEA catalysts with different Cu loadings (4 and 1.3 wt% Cu) were exposed to P by controlled evaporation of H3PO4 in the presence of 8% O2 and 5% H2O at 573 and 773 K. The reaction studies were performed by NH3-storage/TPD, NH3/NO oxidation and standard NH3-SCR. In addition, a combination of several characterisation techniques (ICP–AES, BET surface area, pore size distribution, H2-TPR and XPS) was applied to provide useful information regarding the mechanism of P deactivation. Pore condensation of H3PO4 in combination with pore blocking was observed. However, the measured overall deactivation was found to occur mostly by chemical deactivation reducing the number of the active Cu species and hence deteriorating the redox properties of the Cu/BEA catalysts. The process of P accumulation on the surface preferentially occurs on the “over exchanged” Cu active sites with the formation of phosphate species. This is likely the reason for the more severe deactivation of the 4% Cu/BEA compared to 1.3% Cu/BEA. Further, the higher NOx reduction performance at 773 K of the P-poisoned Cu/BEA catalysts was found to originate from the lower selectivity towards NH3 oxidation, which occurs predominately on the “over-exchanged” sites.
23.	Andonova, Stanislava, 1977, et al. (författare) Enhanced Low Temperature NOx Reduction Performance Over Bimetallic Pt/Rh-BaO Lean NOx Trap Catalysts 2013 Ingår i: Topics in Catalysis. - : Springer Science and Business Media LLC. - 1572-9028 .- 1022-5528. ; 56:1-8, s. 68-74 Tidskriftsartikel (refereegranskat)abstract The overall NSR operation was tested over a bimetallic Pt/Rh-BaO lean NO (x) trap (LNT) catalyst in the range of 473-673 K with simulated diesel exhausts and compared to monometallic 1 wt% Pt/BaO/gamma-Al2O3 and 0.5 wt% Rh/BaO/gamma-Al2O3 samples. The results showed the beneficial effect of the simultaneous presence of 0.5 wt% Pt and 0.25 wt% Rh on the catalytic performance under lean-burn conditions at low temperatures. It was observed that both Pt/BaO/gamma-Al2O3 and Rh/BaO/gamma-Al2O3, which both were mildly aged, have limited NO (x) reduction capacity at 473 K. However, combining Pt and Rh in the NO (x) storage catalyst assisted the NO (x) reduction process to occur at lower temperatures (473 K). One possible reason could be that the combined Pt and Rh sample was more resistant to aging. In addition, the NO2-TPD data showed that the presence of Rh into the Pt/BaO/gamma-Al2O3 system has a considerable effect on the spill-over process of NO (x) , accelerating the release of NO (x) at lower temperatures. These results were in a good agreement with the observed higher rate of oxygen release of the bimetallic Pt/Rh catalyst, leaving a significant number of noble metal sites available for adsorption at lower temperatures than that of the monometallic Pt sample. The superior NSR performance of the bimetallic Pt/Rh/BaO/gamma-Al2O3 catalyst under lean-burn conditions suggested the existence of synergetic promotion effect between the Pt and Rh components, increasing the NO (x) reduction efficiency in comparison with that of the monometallic Pt and Rh-BaO LNT catalysts.
24.	Andonova, Stanislava, 1977, et al. (författare) Mechanistic investigations of the promoting role of Rh on the NSR performance of NOx storage BaO-based catalysts 2013 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 132, s. 266-281 Tidskriftsartikel (refereegranskat)abstract To determine the promoting effect of Rh on the overall NOx storage and reduction (NSR) performance, the studies in the current work were directed toward investigating the storage and release ability over Rh NOx storage BaO-based catalysts compared to Pt. In terms of the metal surface dispersion and the ability of the noble metals to release oxygen at lower temperatures, the synthesized catalysts were characterized by means of dynamic CO chemisorption (RT) and N2O dissociation (RI - 773 K). The NOx storage capacity and the thermal stability of the NOx adsorbed species formed on the surface were analyzed via NOx storage tests and temperature programmed desorption (TPD) without and in the presence of CO2 and H2O. In addition, experiments with lean and rich cycling were conducted at 473,573 and 673 K. The results from the N2O dissociation experiments showed the superior ability of Rh/Al and Rh/Ba/Al catalysts compared to Pt toward O-2 release from the catalytic surface at lower temperatures. In this work, we show that the presence of Rh into the BaO/gamma-Al2O3 system has a considerable effect on the spill-over process of NOx to the precious metal, controlling the subsequent desorption of NOx to occur at lower temperatures in comparison with that of the Pt catalysts. It is suggested a mechanism of NOx desorption where the lower temperature of O-2 release from the surface of Rh catalysts could leave a significant number of noble metal sites accessible for adsorption. Thus this could facilitate the rate of spill-over of NOx from the storage site (the surface sites on gamma-Al2O3 and those on BaO) to the noble metal and their desorption at lower temperatures. The limited NOx storage ability of the Rh-based BaO/gamma-Al2O3 catalysts under lean-burn conditions was found to originate from both low NO oxidation activity and NOx reduction activity, while the main limiting factor for the low NSR performance of the Pt-based catalysts was the limited regeneration ability during rich period.
25.	Andonova, Stanislava, 1977, et al. (författare) Micro-calorimetric studies of NO2 adsorption on Pt/BaO-supported on gamma-Al2O3 NOx storage and reduction (NSR) catalysts-Impact of CO2 2017 Ingår i: Molecular Catalysis. - : Elsevier BV. - 2468-8231. ; 436, s. 43-52 Tidskriftsartikel (refereegranskat)abstract The adsorption of NO2 on Pt/BaO/gamma Al2O3 catalyst has been investigated by micro calorimetry at atmospheric pressure, NOx storage tests and temperature-programmed desorption (TPD). The heat of adsorption of NO2 (Delta H-ads(NO2)) was determined over a wide range of NOx coverages, as the catalyst was exposed to 500/900 ppm NO2 in the absence/presence of 5% CO2 in the range of 423-773 K. The temperature dependent changes of Delta H-ads(NO2) verified the presence of energetically different NOx storage sites with different binding strength. The Delta H-ads(NO2) was found to follow a linear correlation versus temperature, ranging for example from -134.5 to -178.8 kJ/mol for NOx storage over Pt/BaO/gamma Al2O3 at 423-673 K. Thus, at high temperature mostly strongly bound nitrates were formed, while at lower temperature more loosely bound species were also present. Interestingly, the heat of adsorption was higher when using higher NO2 concentration, indicating more bulk barium nitrate formation. This is consistent with the TPD data where a clear high temperature peak was visible after adsorption using 900 ppm NO2 at 423 and 473 K, which was not the case for 500 ppm NO2. Moreover, the micro-calorimetric data also provided evidence in support of the detrimental effect of CO2 on the NOx uptake process. The heat released during the NOx storage in 500 ppm NO2 + 5% CO2 was determined to be significantly reduced ca. -97.8 kJ mol(-1) at 423 K, but ca. -134.5 kJ mol(-1) without CO2. Furthermore, our results show that it is critical to measure heat of adsorption for surface compounds since they are significantly different compared to thermodynamic data for bulk materials.
26.	Andonova, Stanislava, 1977, et al. (författare) The effect of iron loading and hydrothermal aging on one-pot synthesized Fe/SAPO-34 for ammonia SCR 2016 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 180, s. 775-787 Tidskriftsartikel (refereegranskat)abstract The current commercially-available technique for NOx reduction for diesel engines is the selective catalytic reduction (SCR) of NOx with NH3 over Cu zeolites. One of the problems of this technique is their limited ability to convert NOx at diesel particulate filter (DPF) regeneration temperatures. In addition, during regeneration of the DPF there is a risk of thermally deactivating the SCR catalyst. Thus, the aim of the current work was the development of a catalytic system that can reduce NOx both at low as well as high temperature and in addition is stable at high temperature. In order to reach this goal, a Fe/SAPO-34 with chabazite (CHA) structure was combined in a system with a commercial Cu/CHA catalyst. Earlier studies have shown that it is difficult to ion-exchange Fe into CHA structures due to steric hindrance, and we have therefore used a novel synthesis procedure which incorporated iron directly into the zeolite structure. Fe/SAPO-34 with three different Fe-loadings (0.27; 0.47 and 1.03 wt.% Fe) were synthesized and the catalysts were characterized using inductively coupled plasma atomic spectroscopy (ICP-AES), N-2 adsorption-desorption isotherms, BET area measurements and X-ray diffraction (XRD). The chemical composition, porous and crystalline structure of the parent SAPO-34 sample were found to be only slightly affected by addition of small amounts of Fe in the framework zeolite structure. However, more visible changes in the crystallinity were observed in the Fe/SAPO-34 catalysts with higher Fe content, which were attributed to the unit cell size expansion provoked by integration of higher amounts of Fe into the zeolite SAPO-34 framework. The Fe/SAPO-34 with the lowest Fe-loading (0.27 wt.%) was found to be the best catalyst when considering activity as well as high temperature stability. The synthesized Fe/SAPO-34 catalyst demonstrated a significantly improved NOx reduction performance at high temperatures (600-750 degrees C) when compared to a commercial Cu/CHA SCR system, and the combined system (Fe/SAPO-34+ Cu/CHA) exhibited a very good performance in a large temperature interval (200-800 degrees C) that encompasses most diesel exhaust gas conditions.
27.	Andriopoulos, Thanos, et al. (författare) Commencement of and Retention in Web-Based Interventions and Response to Prompts and Reminders : Longitudinal Observational Study Based on Two Randomized Controlled Trials 2021 Ingår i: Journal of Medical Internet Research. - : JMIR Publications. - 1438-8871. ; 23:3 Tidskriftsartikel (refereegranskat)abstract Background: Web-based interventions are effective for several psychological problems. However, recruitment, adherence, and missing data are challenges when evaluating these interventions. Objective: This study aimed to describe the use patterns during the commencement phase, possible retention patterns (continuation of data provision), and responses to prompts and reminders among participants in 2 randomized controlled trials (RCTs) evaluating web-based interventions. Methods: Data on use patterns logged in 2 RCTs aiming to reduce symptoms of anxiety and depression among adult patients recently diagnosed with cancer (AdultCan RCT) and patients with a recent myocardial infarction (Heart RCT) were analyzed. The web-based intervention in the AdultCan trial consisted of unguided self-help and psychoeducation and that in the Heart trial consisted of therapist-supported cognitive behavioral therapy. In total, 2360 participants' use patterns at first log-in, including data collection at baseline (ie, commencement) and at 2 follow-ups, were analyzed. Both the intervention and comparison groups were analyzed. Results: At commencement, 70.85% (909/1283) and 86.82% (935/1077) of the participants in AdultCan and Heart RCTs, respectively, logged in and completed baseline data collection after receiving a welcome email with log-in credentials. The median duration of the first log-in was 44 minutes and 38 minutes in AdultCan and Heart RCTs, respectively. Slightly less than half of the participants' first log-ins were completed outside standard office hours. More than 80% (92/114 and 103/111) of the participants in both trials explored the intervention within 2 weeks of being randomized to the treatment group, with a median duration of 7 minutes and 47 minutes in AdultCan and Heart RCTs, respectively. There was a significant association between intervention exploration time during the first 2 weeks and retention in the Heart trial but not in the AdultCan trial. However, the control group was most likely to retain and provide complete follow-up data. Across the 3 time points of data collection explored in this study, the proportion of participants responding to all questionnaires within 1 week from the prompt, without a reminder, varied between 35.45% (413/1165) and 66.3% (112/169). After 2 reminders, up to 97.6% (165/169) of the participants responded. Conclusions: Most participants in both RCTs completed the baseline questionnaires within 1 week of receiving the welcome email. Approximately half of them answered questions at baseline data collection outside office hours, suggesting that the time flexibility inherent in web-based interventions contributes to commencement and use. In contrast to what was expected, the intervention groups generally had lower completion rates than the comparison groups. About half of the participants completed the questionnaires without a reminder, but thereafter, reminders contributed to both baseline and follow-up retention, suggesting they were effective. Strategies to increase commencement of and retention in eHealth interventions are important for the future development of effective interventions and relevant research.
28.	Antoniou, Antonis C., et al. (författare) Common alleles at 6q25.1 and 1p11.2 are associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers 2011 Ingår i: Human Molecular Genetics. - : Oxford University Press (OUP). - 0964-6906 .- 1460-2083. ; 20:16, s. 3304-3321 Tidskriftsartikel (refereegranskat)abstract Two single nucleotide polymorphisms (SNPs) at 6q25.1, near the ESR1 gene, have been implicated in the susceptibility to breast cancer for Asian (rs2046210) and European women (rs9397435). A genome-wide association study in Europeans identified two further breast cancer susceptibility variants: rs11249433 at 1p11.2 and rs999737 in RAD51L1 at 14q24.1. Although previously identified breast cancer susceptibility variants have been shown to be associated with breast cancer risk for BRCA1 and BRCA2 mutation carriers, the involvement of these SNPs to breast cancer susceptibility in mutation carriers is currently unknown. To address this, we genotyped these SNPs in BRCA1 and BRCA2 mutation carriers from 42 studies from the Consortium of Investigators of Modifiers of BRCA1/2. In the analysis of 14 123 BRCA1 and 8053 BRCA2 mutation carriers of European ancestry, the 6q25.1 SNPs (r(2) = 0.14) were independently associated with the risk of breast cancer for BRCA1 mutation carriers [ hazard ratio (HR) = 1.17, 95% confidence interval (CI): 1.11-1.23, P-trend = 4.5 x 10(-9) for rs2046210; HR = 1.28, 95% CI: 1.18-1.40, P-trend = 1.3 x 10(-8) for rs9397435], but only rs9397435 was associated with the risk for BRCA2 carriers (HR = 1.14, 95% CI: 1.01-1.28, P-trend = 0.031). SNP rs11249433 (1p11.2) was associated with the risk of breast cancer for BRCA2 mutation carriers (HR = 1.09, 95% CI: 1.02-1.17, P-trend = 0.015), but was not associated with breast cancer risk for BRCA1 mutation carriers (HR = 0.97, 95% CI: 0.92-1.02, P-trend = 0.20). SNP rs999737 (RAD51L1) was not associated with breast cancer risk for either BRCA1 or BRCA2 mutation carriers (P-trend = 0.27 and 0.30, respectively). The identification of SNPs at 6q25.1 associated with breast cancer risk for BRCA1 mutation carriers will lead to a better understanding of the biology of tumour development in these women.
29.	Arora, Prakhar, 1987, et al. (författare) Investigating the effect of Fe as a poison for catalytic HDO over sulfided NiMo alumina catalysts 2018 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 227, s. 240-251 Tidskriftsartikel (refereegranskat)abstract The effect of iron (Fe) as poison present in renewable feeds was studied during hydrodeoxygenation (HDO) overmolybdenum based sulfided catalysts. The study was carried out at 6 MPa and 325 °C in batch reaction conditions. Different concentrations of Fe in the feed were tested over MoS2/Al2O3 and NiMoS/Al2O3. A notable drop in activity for the conversion of oxygenates was observed for both catalyst systems with an increased concentration of Fe in the feed. However, the changes in selectivity of products was opposite for unpromoted and Nipromoted catalysts. In the case of the NiMoS catalyst, at higher Fe concentration, the decarbonated product (C17 hydrocarbons) decreased while the direct hydrodeoxygenation product (C18 hydrocarbons)increased. On the contrary, for the base catalyst (MoS2), there was a decrease in the yield of direct hydrodeoxygenation (C18 hydrocarbons) products and an increase in yield of decarbonated products (C17 hydrocarbons). These sulfided catalysts have different sites for these two different reaction routes and they interacted differently with Fe during the deactivation process. With surface deposition of Fe, the ability of these catalysts to create active sites i.e. via sulfur vacancies deteriorated. TEM-EDX results suggested that the effect of Ni as a promoter for the decarbonation route was nullified and a resultant FeMo phase explains the drop in activity and change in selectivity.
30.	Arora, Prakhar, 1987, et al. (författare) Kinetic study of hydrodeoxygenation of stearic acid as model compound for renewable oils 2019 Ingår i: Chemical Engineering Journal. - : Elsevier BV. - 1385-8947. ; 364, s. 376-389 Tidskriftsartikel (refereegranskat)abstract The kinetics during hydrodeoxygenation (HDO) of stearic acid (SA) was investigated to explore the fundamental chemistry and the reaction scheme involved for the reaction with a sulfide NiMo/Al2O3catalyst. Intermediates like octadecanal (C18 O) and octadecanol (C18 OH) were used to resolve the reaction scheme and explain the selectivity for the three major reaction routes (decarboxylation, decarbonylation and direct-HDO). Several reaction parameters, like temperature, pressure, feed concentration and batch-reactor stirring rate, were explored for their effect on changes in rate of conversion and selectivity. A weaker dependence on pressure (40–70 bar) and strong dependence on temperature (275–325 °C) was found for the product distribution during HDO of SA. A model based on Langmuir–Hinshelwood type kinetics was developed to correlate the experimental data. The model well predicted trends in variation of selectivities with the reaction conditions, in part by including intermediates like octadecanol and octadecanal and it predicted phenomenon like inhibiting effects of the fatty acid. The proposed kinetic model is expected to be applicable to liquid phase HDO of different renewable feeds containing long chain fatty acids, methyl esters and triglycerides etc.
31.	Arora, Prakhar, 1987, et al. (författare) The role of catalyst poisons during hydrodeoxygenation of renewable oils 2021 Ingår i: Catalysis Today. - : Elsevier BV. - 0920-5861. ; 367, s. 28-42 Tidskriftsartikel (refereegranskat)abstract Hydrodeoxygenation (HDO) activity of NiMo catalysts have been evaluated in the presence of catalyst poisons in bio-based feedstocks. An in-house synthesized NiMo/Al2O3 catalyst was placed in a refinery unit for biofuel production. Iron (Fe), phosphorus (P) and metals were identified as major contaminants. Calcination treatment was explored to recover the activity of spent catalysts. The effect of Fe, K and phospholipid containing P and Na on catalyst deactivation during hydrodeoxygenation of stearic acid was simulated at lab-scale. Fe caused the most deactivation where the highest feed concentration of the Fe compound resulted in 1480 ppm Fe deposited on the catalyst. Elemental distribution along the radial axis of spent catalysts indicated: Fe deposited only to a depth of 100 μm irrespective of concentration while P and Na from phospholipid and K penetrated deeper in catalyst particles with a distribution profile that was found to be concentration dependent.
32.	Auvray, Xavier, 1986, et al. (författare) Aging of Cu/SSZ-13 for NH3 SCR in mixed lean condition 2018 Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Two catalytic methods have been developed to remove the NOx emissions from diesel vehicles and comply with the emission regulations: the NOx storage and reduction process (NSR) and the reduction of NOx with NH3 (SCR). Advanced systems combining these two methods for an optimum efficiency are now studied. SCR catalysts are subjected alternating lean and rich conditions as well as to high temperatures in rich conditions during deSOx of the LNT material. The purpose of the present work is therefore to determine the response of a Cu/SSZ-13 to several aging treatments at 800°C involving rich and/or lean exposure. Deactivation was observed after all types of aging. However strong differences in deactivation degree exists between aging procedures. Lean aging, for 8h at 800°C, was the most moderate aging tested although it brought about significant activity loss below 250°C. Alternating between long lean periods and short rich periods caused slightly stronger deactivation, which was most significant at 200°C. However, the switching frequency between lean and rich had negligible influence on subsequent activity. As shown in Figure 1, SCR activity after 8h exposure in H2 was outstandingly low. It increased monotonically with temperature to reach a maximum of 58% NO conversion. Further investigation pertaining to the rich treatment was performed. The aging time was reduced to 2h and, for direct comparison, a 32h cycling aging was performed, implying a total rich time of 2h. Both samples were severely impacted over the whole temperature range. It revealed that 2h in rich conditions led to stronger deactivation than 8h in lean and lean/rich conditions, emphasizing the deterioration power of H2. Aging caused by rich conditions was so dominant that additional 30h in lean has negligible influence on SCR below 300°C. However, the long additional exposure to lean conditions lowered significantly the SCR activity between 400 and 500°C.
33.	Auvray, Xavier, 1986, et al. (författare) Comparative Study of SO 2 and SO 2 /SO 3 Poisoning and Regeneration of Cu/BEA and Cu/SSZ-13 for NH 3 SCR 2021 Ingår i: Emission Control Science and Technology. - : Springer Science and Business Media LLC. - 2199-3629 .- 2199-3637. ; 7:4, s. 232-246 Tidskriftsartikel (refereegranskat)abstract Two copper-exchanged zeolites, Cu/SSZ-13 and Cu/BEA, were studied as catalysts for the selective reduction of NOx by NH3 (NH3-SCR). Their activities for standard SCR (NOx = NO) and fast SCR (NOx = 50% NO + 50% NO2) were measured before and after sulfur poisoning at 250 °C. The effect of 30 ppm SO2 and a mixture of 24 ppm SO3 + 6 ppm SO2 was evaluated. The repetition of subsequent activity measurements served as regeneration method in SCR conditions. SO2 deactivated Cu/SSZ-13 whereas Cu/BEA was only moderately affected. SO3 led to stronger deactivation of both catalysts than SO2. However, also for this case, the Cu/BEA was significantly less affected than Cu/SSZ-13, even though Cu/BEA contained larger amount of stored sulfur. One possible reason for this could be the large pores of Cu/BEA, where the sulfur species possibly resulted in less sterical hindrance than in the small pore SSZ-13 structure. NH3 temperature-programmed desorption (NH3-TPD) showed no loss of storage sites upon sulfur treatment and subsequent regeneration. Partial activity recovery was observed after a period in SCR conditions at 400 °C and 500 °C. Temperature at 300 °C was insufficient to regenerate the catalysts. Diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) of NO adsorption suggested that SO2 interacts with the ZCuOH sites on Cu/SSZ-13, causing the strong poisoning.
34.	Auvray, Xavier, 1986, et al. (författare) Deactivation of Cu/SSZ-13 NH3-SCR catalyst by exposure to CO, H2, and C3H6 2019 Ingår i: Catalysts. - : MDPI AG. - 2073-4344. ; 9:11 Tidskriftsartikel (refereegranskat)abstract Lean nitric oxide (NOx)-trap (LNT) and selective catalytic reduction (SCR) are efficient systems for the abatement of NOx. The combination of LNT and SCR catalysts improves overall NOx removal, but there is a risk that the SCR catalyst will be exposed to high temperatures and rich exhaust during the LNTs sulfur regeneration. Therefore, the effect of exposure to various rich conditions and temperatures on the subsequent SCR activity of a Cu-exchanged chabazite catalyst was studied. CO, H2, C3H6, and the combination of CO + H2 were used to simulate rich conditions. Aging was performed at 800 °C, 700 °C, and, in the case of CO, 600 °C, in a plug-flow reactor. Investigation of the nature of Cu sites was performed with NH3-temperature-programed desorption (TPD) and diffuse reflectance infrared Fourier transform spectroscopy (DRIFT) of probe molecules (NH3 and NO). The combination of CO and H2 was especially detrimental to SCR activity and to NH3 oxidation. Rich aging with low reductant concentrations resulted in a significantly larger deactivation compared to lean conditions. Aging in CO at 800 °C caused SCR deactivation but promoted high-temperature NH3 oxidation. Rich conditions greatly enhanced the loss of Brønsted and Lewis acid sites at 800 °C, indicating dealumination and Cu migration. However, at 700 °C, mainly Brønsted sites disappeared during aging. DRIFT spectroscopy analysis revealed that CO aging modified the Cu2+/CuOH+ ratio in favor of the monovalent CuOH+ species, as opposed to lean aging. To summarize, we propose that the reason for the increased deactivation observed for mild rich conditions is the transformation of the Cu species from Z2Cu to ZCuOH, possibly in combination with the formation of Cu clusters. © 2019, MDPI AG. All rights reserved.
35.	Auvray, Xavier, 1986, et al. (författare) Effect of enhanced support acidity on the sulfate storage and the activity of Pt/γ-Al2O3 for no oxidation and propylene oxidation 2014 Ingår i: Catalysis Letters. - : Springer Science and Business Media LLC. - 1572-879X .- 1011-372X. ; 144:1, s. 22-31 Tidskriftsartikel (refereegranskat)abstract NO oxidation and propylene oxidation were studied on standard and acidity-enhanced Pt/Al 2 O 3 catalyst. Deactivation by platinum oxide formation was suppressed by the presence of chlorine and sulfates. After a long SO 2 exposure, the activity of modified catalysts was higher than the standard catalyst. The aged chlorinated sample showed the best propylene oxidation activity while the sulfated one exhibited the best NO conversion. © 2013 Springer Science+Business Media New York.
36.	Auvray, Xavier, 1986, et al. (författare) Enhancement of NO and C3H6 oxidation by SO2 treatment over Pt/Al2O3 2013 Ingår i: 23rd Meeting of the North American Catalysis Society, Louisville, KY, June 2013. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract Oxidation catalyst is used in automotive exhaust treatment to convert CO and hydrocarbons into CO2 and water. They also have the specific function of converting NO into NO2 in Diesel vehicles, which increases the efficiency of NOx-removal system and participates in the particle filter regeneration. Automotive catalysts are affected by thermal treatments and gas composition. SO2 is one of the undesirable compounds of exhaust gases that is able to store on the catalyst [1] and hinder the reaction. Despite its low concentration, SO2 affects significantly the catalyst. Ageing in SO2-containing atmosphere has shown to promote platinum migration and increase the ability of Pt/Al2O3 catalysts to oxidize NO in dry conditions [2]. In the present work, model catalysts were aged in presence of SO2 at 250 °C and tested for NO and C3H6 oxidation in wet conditions. Various reductive treatments were performed after ageing in order to shed a light on the stability and impact on activity of the different types of adsorbed sulfur species. The hysteresis phenomenon observed for both reactions was also affected by the presence of surface sulfur.The performance of a typical oxidation catalyst was improved by pretreatment in presence of SO2 and subsequent elimination of the less stable stored sulfur species. Further activity was gained during the cooling for both NO and C3H6 oxidation after complete removal of sulfur.
37.	Auvray, Xavier, 1986, et al. (författare) Enhancement of NO and C3H6 oxidation by SO2 treatment over Pt/Al2O3 2013 Ingår i: Energirelaterad fordonsforskning 2013, Örebro, April 2013. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract The oxidation of NO and C3H6 over a 1wt% Pt/Al2O3 catalyst was studied. Ageing of the catalyst at 250 °C for 22 h with a gas flow containing 30 ppm SO2 decreased the dispersion and increased the catalytic activity for the two reactions. Two types of sulfur species were formed during ageing, the less stable of which have to be eliminated to recover high activity. The most stable species, probably sulfates stored on the support, affect the conversion during extinction only.
38.	Auvray, Xavier, 1986, et al. (författare) Kinetic modeling of NH3-SCR over a supported Cu zeolite catalyst using axial species distribution measurements 2015 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 163, s. 393-403 Tidskriftsartikel (refereegranskat)abstract In this study, a kinetic model is developed for NH3-SCR over a honeycomb-monolith-supported Cu-zeolites using intra-catalyst axial species distribution measurements. An ammonia TPD experiment, together with micro calorimetry data were used for tuning the ammonia adsorption and desorption properties. The spatial distribution for NO oxidation, NH3 oxidation and NH3 "Standard" SCR were modeled between 200 and 400 degrees C. Four-step protocol measurements were employed in order to validate the transient functions of the model. The resulting kinetic model provides good spatiotemporal simulation of the SCR reaction and component reactions throughout the monolith catalyst system.
39.	Auvray, Xavier, 1986, et al. (författare) Lean and rich aging of a Cu/SSZ-13 catalyst for combined lean NO x trap (LNT) and selective catalytic reduction (SCR) concept 2019 Ingår i: Catalysis Science and Technology. - : Royal Society of Chemistry (RSC). - 2044-4753 .- 2044-4761. ; 9:9, s. 2152-2162 Tidskriftsartikel (refereegranskat)abstract © 2019 The Royal Society of Chemistry. In the combined lean NO x trap (LNT) and selective catalytic reduction (SCR) concept, the SCR catalyst can be exposed to rich conditions during deSO x of the LNT. Aging of Cu/SSZ-13 SCR catalysts, deposited on a cordierite monolith, was therefore studied in rich, lean and cycling lean/rich operations at 800 °C (lean condition: 500 ppm NO, 8% O 2 , 10% H 2 O and 10% CO 2 ; rich condition: 500 ppm NO, 1% H 2 , 10% H 2 O and 10% CO 2 ). The structure of the catalyst was investigated by X-ray diffraction (XRD), surface area measurements and scanning transmission electron microscopy (STEM). In general, aging decreased the SCR activity and NH 3 oxidation. However, rich conditions showed a very rapid and intense deactivation, while lean aging led to only a small low-temperature activity decrease. The XRD results showed no sign of structure collapse, but the number of active sites, as titrated by NH 3 temperature-programed desorption (NH 3 -TPD) and in situ DRIFTS, revealed an important loss of acid sites. NH 3 storage was significantly more depleted after rich aging than after lean aging. The Lewis sites, corresponding to exchange Cu 2+ , were preserved to some extent in lean conditions. Lean aging also decreased the enthalpy of NH 3 adsorption from -158 kJ mol -1 to -136 kJ mol -1 . Moreover, a comparison of aging in lean-rich cycling conditions with aging only in rich conditions revealed that adding lean events did not hinder or reverse the deactivation, and it was mainly the time in rich conditions that determined the extent of the deactivation. The STEM images coupled with elemental analysis revealed the formation of large Cu particles during rich aging. Conversely, Cu remained well dispersed after lean aging. These results suggest that the copper migration and agglomeration in large extra-framework particles, accelerated by the action of hydrogen, caused the observed severe deactivation.
40.	Auvray, Xavier, 1986, et al. (författare) Local ammonia storage and ammonia inhibition in a monolithic copper-beta zeolite SCR catalyst 2012 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 126, s. 144-152 Tidskriftsartikel (refereegranskat)abstract Selective catalytic reduction of NO with NH3 was studied on a Cu-beta zeolite catalyst, with specific focus on the distributed NH3 capacity utilization and inhibition. In addition, several other relevant catalyst parameter distributions were quantified including the SCR zone, or catalyst region where SCR occurs, and NO and NH3 oxidation. We show that the full NH3 capacity (100% coverage) is used within the SCR zone for a range of temperatures. By corollary, unused NH3 capacity exists downstream of the SCR zone. Consequently, the unused capacity relative to the total capacity is indicative of the portion of the catalyst unused for SCR. Dynamic NH3 inhibition distributions, which create local transient conversion inflections, are measured. Dynamic inhibition is observed where the gas phase NH3 and NO concentrations are high, driving rapid NH3 coverage buildup and SCR. Accordingly, we observe dynamic inhibition at low temperatures and in hydrothermally aged states, but predict its existence very near the catalyst front in higher conversion conditions where we did not specifically monitor its impact. While this paper addresses some general distributed SCR performance parameters including Oxidation and SCR zone, our major new contributions are associated with the NH3 capacity saturation within the SCR zone and dynamic inhibition distributions and the associated observations. These new insights are relevant to developing accurate models, designs and control strategies for automotive SCR catalyst applications.
41.	Auvray, Xavier, 1986, et al. (författare) Stability and activity of Pd-, Pt- and Pd-Pt catalysts supported on alumina for NO oxidation 2015 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 168, s. 342-352 Tidskriftsartikel (refereegranskat)abstract The association of palladium and platinum supported on alumina was studied for diesel oxidation catalyst application. The effect of propene, water and their combination on NO oxidation activity was investigated in flow reactor over Pt/Al2O3, Pd/Al2O3 and two Pt-Pd/Al2O3 catalysts, prepared by co-impregnation and sequential impregnation of the metals. Contrary to Pd/Al2O3, activity improvement due to the repetition of activity test was observed on Pt/Al2O3 and both Pt-Pd/Al2O3. Metal sintering during activity test was revealed by CO chemisorption. The bimetallic catalysts reached their final stability and activity before Pt/Al2O3. The presence of water decreased the NO oxidation activity of all catalysts and the propene completely inhibited NO oxidation at low temperature until propene combustion occurred. The addition of palladium to Pt/Al2O3 was found very efficient to oxidize propene and therefore significantly limited the inhibition of NO oxidation by propene. A mechanism was proposed to explain the NO oxidation promotion lying behind the addition of Pd. DRIFT measurements and flow reactor experiments showed that propene was less stable and able to react with surface nitrates on Pd-containing catalyst at low temperature (175 degrees C). On Pt/Al2O3, however, the propene consumption proceeded initially through selective catalytic reduction of NO, which took place at higher temperature (240 degrees C). In this way, propene combustion and consequently NO oxidation occurred at lower temperature on bimetallic catalysts than on Pt/Al2O3.
42.	Auvray, Xavier, 1986, et al. (författare) Sulfur Dioxide Exposure: A Way To Improve the Oxidation Catalyst Performance 2013 Ingår i: Industrial & Engineering Chemistry Research. - : American Chemical Society (ACS). - 1520-5045 .- 0888-5885. ; 52:41, s. 14556-14566 Tidskriftsartikel (refereegranskat)abstract The oxidation of nitric oxide and propylene was studied over a model alumina-supported platinum catalyst. Two treatments (22 h at 250 degrees C and 2 h at 800 degrees C) involving sulfur dioxide were performed in order to understand the effect of SO2 aging. The role and stability of sulfur species stored during aging were investigated by the reduction of sulfated samples at 500 degrees C and temperature-programmed reduction (TPR) up to 800 degrees C. The low activity obtained after aging without reduction revealed the poisoning effect of surface sulfur species. The reduction at 500 degrees C released half of the surface species, which increased the catalytic activity for both NO and C3H6 oxidation. The TPR removed the most stable sulfur species and improved the activity during cooling. The catalyst aged in SO2 at high temperature showed the greatest activity for both reactions because of SO2 exposure and low sulfur storage.
43.	Auvray, Xavier, 1986, et al. (författare) The addition of alkali and alkaline earth metals to Pd/Al2O3 to promote methane combustion. Effect of Pd and Ca loading 2018 Ingår i: Catalysis Today. - : Elsevier BV. - 0920-5861. ; 299, s. 212-218 Tidskriftsartikel (refereegranskat)abstract Methane catalytic combustion was studied on Pd/Al2O3 catalysts modified with alkali and alkaline earth metals (K, Na, Ca and Ba). Temperature-programmed reactions were performed in flow reactor on washcoated monolithic samples. CO chemisorption was carried out and BET surface area was measured in order to characterize the catalysts. Addition of alkaline metals was either beneficial or detrimental for methane oxidation, depending on the catalyst composition and pretreatment. High loading of alkaline modifiers and cooling in reaction mixture increased the light-off temperature of methane oxidation. However, promotion was achieved by doping with calcium after cooling in inert atmosphere. Furthermore, calcium doping was more beneficial in presence of NO, which inhibits the methane oxidation. Higher Pd loading enhanced CH4 oxidation, whereas the effect of calcium depends on Ca and Pd loading. Indeed, the promotion by calcium was more pronounced on catalysts with 5% Pd than with 2.5% Pd. On 2.5% Pd catalyst, high Ca loading was detrimental for CH4 oxidation. In contrary, on 5% Pd catalyst, even 1.51 wt% calcium (the highest loading used) induced promotion, which demonstrates a correlation between Ca: Pd ratio and promotion/inhibition effect. Samples with a mass ratio of 0.15 showed the best activity.
44.	Auvray, Xavier, 1986, et al. (författare) The effect of gas composition during thermal aging on the dispersion and NO oxidation activity over Pt/Al2O3 catalyst 2012 Ingår i: CapoC 9, August 2012, Brussels, Belgium. Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract The effect of aging atmosphere (Ar, H2, O2, SO2, SO2+O2) during thermal aging of Pt/Al2O3 model diesel oxidation catalysts was studied. More specifically, the impact of the aging on the NO oxidation activity and platinum dispersion was investigated. Thermal aging caused a decrease in dispersion and an increase in NO oxidation performance. However, the aging behavior was strongly correlated with the nature of the ageing atmosphere. Catalysts with similar dispersion could have very different NO oxidation activity, depending on which atmosphere that they were aged with.
45.	Azis, Muhammad Mufti, 1983, et al. (författare) Evaluation of H2 effect on NO oxidation over a diesel oxidation catalyst 2015 Ingår i: Applied Catalysis B: Environmental. - : Elsevier BV. - 0926-3373 .- 1873-3883. ; 179, s. 542-550 Tidskriftsartikel (refereegranskat)abstract The influence of H2 on NO oxidation over Pt/Al2O3 as a model DOC catalyst was evaluated with various DOC feed mixtures. Discrimination of surface chemistry and exothermal effects due to addition of H2 was made based on differences in time scales of transient responses. H2 was proposed to retard Pt oxide formation mainly at low temperatures (ca.
46.	Bennet, Louise, et al. (författare) Diabetes och etnicitet 2020. - 1 Ingår i: Diabetes. - 9789144131108 ; , s. 365-374 Bokkapitel (populärvet., debatt m.m.)
47.	Bergvall, Niklas, et al. (författare) Upgrading of fast pyrolysis bio-oils to renewable hydrocarbons using slurry- and fixed bed hydroprocessing 2024 Ingår i: Fuel processing technology. - : Elsevier B.V.. - 0378-3820 .- 1873-7188. ; 253 Tidskriftsartikel (refereegranskat)abstract Liquefaction of lignocellulosic biomass through fast pyrolysis, to yield fast pyrolysis bio-oil (FPBO), is a technique that has been extensively researched in the quest for finding alternatives to fossil feedstocks to produce fuels, chemicals, etc. Properties such as high oxygen content, acidity, and poor storage stability greatly limit the direct use of this bio-oil. Furthermore, high coking tendencies make upgrading of the FPBO by hydrodeoxygenation in fixed-bed bed hydrotreaters challenging due to plugging and catalyst deactivation. This study investigates a novel two-step hydroprocessing concept; a continuous slurry-based process using a dispersed NiMo-catalyst, followed by a fixed bed process using a supported NiMo-catalyst. The oil product from the slurry-process, having a reduced oxygen content (15 wt%) compared to the FPBO and a comparatively low coking tendency (TGA residue of 1.4 wt%), was successfully processed in the downstream fixed bed process for 58 h without any noticeable decrease in catalyst activity, or increase in pressure drop. The overall process resulted in a 29 wt% yield of deoxygenated oil product (0.5 wt% oxygen) from FPBO with an overall carbon recovery of 68%.
48.	Bettegowda, Chetan, et al. (författare) Detection of circulating tumor DNA in early- and late-stage human malignancies 2014 Ingår i: Science Translational Medicine. - : American Association for the Advancement of Science (AAAS). - 1946-6234 .- 1946-6242. ; 6:224, s. 224ra24- Tidskriftsartikel (refereegranskat)abstract The development of noninvasive methods to detect and monitor tumors continues to be a major challenge in oncology. We used digital polymerase chain reaction-based technologies to evaluate the ability of circulating tumor DNA (ctDNA) to detect tumors in 640 patients with various cancer types. We found that ctDNA was detectable in >75% of patients with advanced pancreatic, ovarian, colorectal, bladder, gastroesophageal, breast, melanoma, hepatocellular, and head and neck cancers, but in less than 50% of primary brain, renal, prostate, or thyroid cancers. In patients with localized tumors, ctDNA was detected in 73, 57, 48, and 50% of patients with colorectal cancer, gastroesophageal cancer, pancreatic cancer, and breast adenocarcinoma, respectively. ctDNA was often present in patients without detectable circulating tumor cells, suggesting that these two biomarkers are distinct entities. In a separate panel of 206 patients with metastatic colorectal cancers, we showed that the sensitivity of ctDNA for detection of clinically relevant KRAS gene mutations was 87.2% and its specificity was 99.2%. Finally, we assessed whether ctDNA could provide clues into the mechanisms underlying resistance to epidermal growth factor receptor blockade in 24 patients who objectively responded to therapy but subsequently relapsed. Twenty-three (96%) of these patients developed one or more mutations in genes involved in the mitogen-activated protein kinase pathway. Together, these data suggest that ctDNA is a broadly applicable, sensitive, and specific biomarker that can be used for a variety of clinical and research purposes in patients with multiple different types of cancer.
49.	Bexelius, Maria, et al. (författare) 27 forskare : Så kan EU:s murar rivas 2015 Ingår i: Dagens samhälle. - : Sveriges kommuner och landsting. - 1652-6511. ; :20150923 Tidskriftsartikel (populärvet., debatt m.m.)
50.	Bjarnegård, Elin, 1976-, et al. (författare) Gender, peace and armed conflict 2015 Ingår i: SIPRI Yearbook 2015. - Oxford : Oxford University Press. - 9780198737810 ; , s. 101-109 Bokkapitel (refereegranskat)

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