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Abstract This work investigates the long-term performance of Ba-Ni-hexaaluminate, BaNixAl12−xO19 as a catalyst in reforming of 1-methyl naphthalene and/or methane in a model-gas simulating that from a circulating fluidized bed (CFB) gasifier during 23–29 h in a lab scale set-up, as well as the tendency for coke formation, sintering and sulphur poisoning. 1-Methyl naphthalene is used as a tar model substance. The Ba-Ni-hexaaluminate induces a high conversion of both compounds in the temperatures investigated (850 and 950 °C) under sulphur-free conditions. In sulphur-containing gas, the methane conversion stops at 20 ppm H2S and the reforming of 1-MNP at 850 °C is slightly reduced at 100 ppm. Graphic Abstract

This work investigates the performance of Ba–Ni-hexaaluminate, BaNixAl12 − xO19, as a new catalyst in the steam-reforming of tars. Substituted hexaaluminates are synthesized and characterized. Steam reforming tests are carried out with both a model-substance (1-methylnaphthalene) and a slip-stream from a circulating fluidized bed gasifier. The water–gas-shift activity is studied in a lab-scale set-up. Barium–nickel substituted hexaaluminates show a high catalytic activity for tar cracking, and also shows activity for water–gas-shift. This work investigates the performance of Ba–Ni-hexaaluminate, BaNixAl12−xO19, as a new catalyst in the steam-reforming of tars. Substituted hexaaluminates are synthesized and characterized. Steam reforming tests are carried out with both a model-substance (1-methylnaphthalene) and a slip-stream from a circulating fluidized bed gasifier. The water–gas-shift activity is studied in a lab-scale set-up. Barium–nickel substituted hexaaluminates show a high catalytic activity for tar cracking, and also shows activity for water–gas-shift.

In an era characterized by a move towards a “knowledge society”, universities are central in fostering “knowledgeability”, that is the reflexive understanding of knowledge in knowledge societies. The objective of “knowledgeability” can be met through creating a stronger link between education and research. Furthermore, overall student performance, for example in critical thinking and problem solving, can be improved if research-related activities are incorporated into the curriculum. The aim of this paper is to use inter-national examples to discuss the research- education nexus from four different perspectives, namely context, policy, im- plementation and quality, with case studies from higher education institutions in Singapore and Sweden. We suggest that different integrative technologies can be used to enhance the links, but it will be essential to consider the inputs of training, service and support in using new technology. Interestingly, the act of evaluating the link between edu- cation and research will increase awareness of this linkage by stakeholders involved in both education and research. In turn the link can be strengthened, contributing to increased quality in both education and research.

Microsomal prostaglandin E synthase-1 (mPGES-1) inhibition has been suggested as an alternative to cyclooxygenase (COX) inhibition in the treatment of pain and inflammation. We characterized a selective inhibitor of mPGES-1 activity (compound III) and studied its impact on the prostanoid profile in various models of inflammation. Compound III is a benzoimidazole, which has a submicromolar IC50 in both human and rat recombinant mPGES-1. In cellular assays, it reduced PGE2 production in A549 cells, mouse macrophages and blood, causing a shunt to the prostacyclin pathway in the former two systems. Lastly, we assayed compound III in the air pouch model to verify its impact on the prostanoid profile and compare it to the profile obtained in mPGES-1 k.o. mice. As opposed to mPGES-1 genetic deletion, which attenuated PGE2 production and caused a shunt to the thromboxane pathway, mPGES-1 inhibition with compound III reduced PGE2 production and tended to decrease the levels of other prostanoids.

Microsomal prostaglandin E(2) synthase-1 (MPGES1) catalyzes the formation of prostaglandin E(2) from the endoperoxide prostaglandin H(2). MPGES1 expression is induced in inflammatory diseases, and this enzyme is regarded as a potential drug target. To aid in the drug discovery effort, a simple method for determination of inhibition mechanism and potency toward both prostaglandin H(2) and glutathione (GSH) has been developed. Using an assay with thiobarbituric acid-based detection, the inhibitory effects of six MPGES1 inhibitors were evaluated. The IC(50) values obtained at three substrate (S) concentrations ([S]K(M), [S]≈K(M), [S]K(M)) were used to estimate inhibition modality and inhibition constant values. This facilitated strategy is a useful and general screening method to evaluate the inhibitory effects of new drug compounds.

Patients with diseases characterized by chronic inflammation, caused by infection or cancer, have T cells and NK cells with impaired function. The underlying molecular mechanisms are diverse, but one of the major mediators in this immune suppression is oxidative stress caused by activated monocytes, granulocytes, or myeloid-derived suppressor cells. Reactive oxygen species can seriously hamper the efficacy of active immunotherapy and adoptive transfer of T and NK cells into patients. In this study, we have evaluated whether enhanced expression of the antioxidant enzyme catalase in human T cells can protect them against reactive oxygen species. Human CD4+ and CD8+ T cells retrovirally transduced with the catalase gene had increased intracellular expression and activity of catalase. Catalase transduction made CD4+ T cells less sensitive to H2O2-induced loss-of-function, measured by their cytokine production and ability to expand in vitro following anti-CD3 stimulation. It also enhanced the resistance to oxidative stress-induced cell death after coculture with activated granulocytes, exposure to the oxidized lipid 4-hydroxynonenal, or H2O2. Expression of catalase by CMV-specific CD8+ T cells saved cells from cell death and improved their capacity to recognize CMV peptide-loaded target cells when exposed to H2O2. These findings indicate that catalase-transduced T cells potentially are more efficacious for the immunotherapy of patients with advanced cancer or chronic viral infections.

Production of synthesis gas by catalytic reforming of product gas from biomass gasification can lead to catalyst deactivation by the exposure to ash compounds present in the flue gas. The impact of fly ash from biomass gasification on reforming catalysts was studied at the laboratory scale. The investigated catalyst was Pt/Rh based, and it was exposed to generated K2SO4 aerosol particles and to aerosol particles produced from the water-soluble part of biomass fly ash, originating from a commercial biomass combustion plant. The noble metal catalyst was also compared with a commercial Ni-based catalyst, exposed to aerosol particles of the same fashion. To investigate the deactivation by aerosol particles, a flow containing submicrometer-size selected aerosol particles was led through the catalyst bed. The particle size of the poison was measured prior to the catalytic reactor system. Fresh and aerosol particle exposed catalysts were characterized using BET surface area, XRPD (X-ray powder diffraction), and H2 chemisorption. The Pt/Rh catalyst was also investigated for activity in the steam methane reforming reaction. It was found that the method to deposit generated aerosol particles on reforming catalysts could be a useful procedure to investigate the impact of different compounds possibly present in the product gas from the gasifier, acting as potential catalyst poisons. The catalytic deactivation procedure by exposure to aerosol particles is somehow similar to what happens in a real plant, when a catalyst bed is located subsequent to a biomass gasifier or a combustion boiler. Using different environments (oxidizing, reducing, steam present, etc.) in the aerosol generation adds further flexibility to the suggested aerosol deactivation method. It is essential to investigate the deactivating effect at the laboratory scale before a full-scale plant is taken into operation to avoid operational problems.

The deactivation of a commercial Selective Catalytic Reduction (SCR) catalyst, of V2O5−WO3/TiO2 type, has been studied through comparisons with results from a full-scale biomass combustion plant to that with laboratory experiments. In the latter, the catalyst was exposed to KCl and K2SO4 by both wet impregnation with diluted salt solutions and deposition of generated submicrometer aerosol particles by means of an electrostatic field. The reactivity of fresh and deactivated samples was examined in the SCR reaction. Chemical and physical characterizations were focusing on internal structures and chemical composition. Deposition of submicrometer sized particles on the monolithic SCR catalyst was shown to induce deactivation with characteristics resembling those obtained in a commercial biomass combustion plant.

The deactivation of alumina-supported platinum catalyst for VOC oxidation by long-term exposure for hexamethyldisiloxane (HMDS) has been investigated in a pilot scale reactor for up to 1000 h of exposure. Catalyst samples were characterized by ICP-AES, BET and silicon deposition by SEM. Catalyst activity was investigated using oxidation of ethyl acetate showing deactivation of the catalyst samples as exposed to HMDS increasing with exposure time. Silicon was shown to deposit on the catalyst as well as on the blank alumina support. SEM investigation of an individual pellet revealed a radial eggshell silicon distribution. CO chemisorption showed strong decrease of Pt active sites after deactivation, while still maintaining reasonable oxidation levels of ethyl acetate.

Generated aerosol particle deposition has been applied in laboratory scale to induce deactivation of commercial Selective Catalytic Reduction (SCR) catalysts Of V2O5-WO3/TiO2 monolithic type. The m ...

An HbA1c threshold of ≥ 42 mmol/mol has been proposed to diagnose prediabetes. The sensitivity, specificity and positive predictive value of the proposed threshold for detection of individuals with prediabetes was examined in a study of 573 randomly selected individuals from Vara and Skövde. In addition, the utility of the FINDRISC questionnaire and of a fasting glucose test in combination with three short questions concerning BMI, heredity for type 2 diabetes and known hypertension was examined. Results from an oral glucose tolerance test were used as reference. The sensitivity of HbA1c and FINDRISC to detect individuals with IGT was 16 and 26 per cent respectively. Questions regarding BMI, heredity and hypertension together with a fasting glucose test yielded a sensitivity of 50%, but a lower specificity and positive predictive value. We conclude that HbA1c inefficiently detected individuals with impaired glucose tolerance and that oral glucose tolerance tests can still preferably be recommended.

The deactivation of a commercial selective catalytic reduction (SCR) catalyst of type V2O5−WO3/TiO2 has been studied in this work through comparisons of results from a full-scale biomass combustion plant with those from laboratory experiments. In the latter, the catalyst was exposed to KCl, K2SO4, and ZnCl2 by both wet impregnation with diluted salt solutions and deposition of generated submicrometer aerosol particles by means of an electrostatic field. The reactivity of freshly prepared and deactivated catalyst samples was examined in the SCR reaction, for which the influence of the different salts and the method of exposure were explored. Chemical and physical characterizations of the catalyst samples were carried out focusing on surface area, pore volume, pore size, chemical composition, and the penetration profiles of potassium and zinc. Particle-deposition deactivation as well as commercially exposed catalyst samples were shown to impact surface area and catalyst activity similarly and to have penetration profiles with pronounced peaks. Salt impregnation influenced pore sizes and catalyst activity more strongly and showed flat penetration profiles. Deposition of submicrometer-sized particles on the monolithic SCR catalyst has been shown to induce deactivation of the catalyst with characteristics resembling those obtained in a commercial biomass combustion plant; the laboratory process can be used to further assess the deactivation mechanism by biomass combustion.

Much new information on C-peptide physiology has appeared during the past 20 years. It has been shown that C-peptide binds specifically to cell membranes, elicits intracellular signaling via G-protein and Ca2+ -dependent pathways, resulting in activation and increased expression of endothelial nitric oxide synthase, Na+, K+ -ATPase and several transcription factors of importance for anti-inflammatory, anti-oxidant and cell protective mechanisms. Studies in animal models of diabetes and early clinical trials in patients with type 1 diabetes demonstrate that C-peptide in replacement doses elicits beneficial effects on early stages of diabetes-induced functional and structural abnormalities of the peripheral nerves, the kidneys and the retina. Much remains to be learned about C-peptide's mechanism of action and long-term clinical trials in type 1 diabetes subjects will be required to determine C-peptide's clinical utility. Nevertheless, even a cautious evaluation of the available evidence presents the picture of a bioactive endogenous peptide with therapeutic potential.

Lipid bilayers containing 5% nitrilotriacetic acid (NTA) lipids supported on SiO2 have been used as a template for immobilization of oligohistidine-tagged single-chained antibody fragments (scFvs) directed against cholera toxin. It was demonstrated that histidine-tagged scFvs could be equally efficiently coupled to an NTA-Ni2+-containing lipid bilayer from a purified sample as from an expression supernatant, thereby providing a coupling method that eliminates time-consuming protein prepurification steps. Irrespective of whether the coupling was made from the unpurified or purified antibody preparation, the template proved to be efficient for antigen (cholera toxin) detection, verified using quartz crystal microbalance with dissipation monitoring. In addition, via a secondary amplification step using lipid vesicles containing GM1 (the natural membrane receptor for cholera toxin), the detection limit of cholera toxin was less than 750 pM. To further strengthen the coupling of scFvs to the lipid bilayer, scFvs containing two histidine tags, instead of just one tag, were also evaluated. The increased coupling strength provided via the bivalent anchoring significantly reduced scFv displacement in complex solutions containing large amounts of histidine-containing proteins, verified via cholera toxin detection in serum.

Quartz crystal microbalance with dissipation (QCM-D) measurements were used to investigate the adsorption of human fibrinogen, human serum albumin, bovine hemoglobin, horse heart cytochrome c, human immunoglobulin (hIgG), and 10% fetal bovine serum on supported bilayers of egg-phosphatidylcholine (eggPC) lipids. For comparison the adsorption of fibrinogen and hIgG to eggPC bilayers was also studied with surface plasmon resonance (SPR). The supported bilayers were formed in situ by vesicle adhesion and spontaneous fusion onto a SiO(2) surface. The supported lipid bilayer is highly protein resistant: The irreversible adsorption measured with the QCM-D technique was below the detection level, while reversible protein adsorption was detected for all the proteins in the range 0.3-4% of the saturation coverage on a hydrophobic thiol monolayer on gold. The adsorbed amounts were slightly higher for the SPR measurements. Possible mechanisms for the protein resistance of eggPC bilayers are briefly discussed.

Background and Purpose In order to improve the physiotherapeutic treatment of patients with long-standing knee pain, it it important to identify osteoarthritis (OA) of the knee at an early stage. The aim of the present study was to test the value of single functional measurement variables with the focus on the lower extremities for the association to early radiographic signs of OA of the knee. The classification by Ahlback grade I (joint space narrowing) was used in a cohort of 204 individuals aged 35–54 years with long-standing knee pain. Methods The following five selected tests were employed: three tests of static and dynamic balance (Balance I–III); one test of muscle strength (one-leg-rising-test, OLR); and one test of walking ability (time for walking 300 m indoors). Odds ratios (ORs) were calculated with a 95% confidence interval. Results and Conclusions Results revealed that the selected tests of functional capacity due to rather low sensitivity (0.15–0.81), specificity (0.21–0.86) and inconclusive odds ratios (0.78–1.62) are probably of limited value as assessment tools to find radiographic knee OA in a younger population with mild OA. However, it is also possible to conclude that in middle-aged individuals with chronic knee pain, the diagnosis of radiographic OA is not related to the functional capacity as measured in the present study. Copyright © 1998 Whurr Publishers Ltd.

Microsomal prostaglandin E synthase (mPGES)-1 inhibition has been proposed as an alternative to cyclooxygenase (COX) inhibition in the treatment of pain and inflammation. This novel approach could potentially mitigate the gastro-intestinal and cardiovascular side effects seen after long-term treatment with traditional non-steroidal anti-inflammatory drugs (NSAIDs) and Coxibs respectively. Several human mPGES-1 inhibitors have been developed in the recent years. However, they were all shown to be considerably less active on rodent mPGES-1, precluding the study of mPGES-1 inhibition in rodent models of inflammation and pain. The aim of this study was to characterize the new mPGES-1 inhibitor compound II, a pyrazolone that has similar potency on rat and human recombinant mPGES-1, in experimental models of inflammation. In cell culture, compound II inhibited PGE2 production in synovial fibroblasts from patients with rheumatoid arthritis (RASF) and in rat peritoneal macrophages. In vivo, compound II was first characterized in the rat air pouch model of inflammation where treatment inhibited intra-pouch PGE2 production. Compound II was also investigated in a rat adjuvant-induced arthritis model where it attenuated both the acute and delayed inflammatory responses. In conclusion, compound II represents a valuable pharmacological tool for the study of mPGES-1 inhibition in rat models.

Policy interest in international surveys on Adult Learning (AL) has increased strongly. AL survey data are used as benchmarks for a country‘s educational system. However, results of key indicators like participation in learning activities often vary remarkably between different data sources. Stating that these differences are due to varying concepts and methods is not enough. The key question is: Which figures represent reality more appropriately? Therefore, evaluation of survey concepts and methods is crucial for international comparison of Adult Learning. This report provides guidelines on methodological and conceptual issues. Part one covers methodological aspects while part two deals with concepts, definitions and example questions. Recommendations are based on input from 14 countries...

Simultaneous quartz crystal microbalance with dissipation monitoring (QCM-D) and surface plasmon resonance (SPR) measurements are used to analyze the surface kinetics of two biomacromolecular systems, one lipid and one protein based, undergoing surface-induced conformational changes. First we establish a theoretical platform, which allows quantitative analysis of the combined SPR and QCM-D data. With this theoretical base, new information can be extracted, not obtainable with either technique alone. As an example we demonstrate how time-resolved measurements with these two techniques in combination--yielding three independent measured quantities--add new information about (i) kinetics, i.e. number of adsorbed molecules per unit area versus time, and (ii) temporal variation in the mass fraction of coupled water versus coverage. In particular, it is demonstrated for the first time, how the kinetics of the process during which adsorbed vesicles are spontaneously transformed into a supported phospholipid bilayer (SPB) on SiO(2) can be quantitatively separated into its two dominating states: adsorbed vesicles and supported planar bilayer patches. In addition, the relevance of dynamically coupled water for interpretation and modeling of the QCM-D response during bilayer formation is discussed and further illustrated with a second model system: streptavidin adsorption on a biotin-modified SPB. A very strong coverage dependence in the number of water molecules per protein sensed by the QCM is demonstrated, with strong implications for the use of QCM as a tool for quantitative determination of protein mass uptake kinetics.

We report experimental and theoretical results on the effect of electromagnetic coupling between metal particles in surface-enhanced Raman scattering (SERS). Model calculations of the near-field optical properties of Ag and Au nanoparticle-aggregates show that the electromagnetic surface-enhancement factor can reach 11 orders-of-magnitude in gaps between nearly touching particles. Single particles exhibit a much weaker enhancement, unless the particles contain extremely sharp surface protrusions. Data on spectral fluctuations in single-molecule SERS and measurements on the efficiency of nanofabricated SERS substrates give experimental support for the idea that an efficient interparticle coupling is a necessary requirement for an ultra-high surface-enhancement. We suggest a route for biorecognition induced coupling of metal particles for use in biosensing applications.