| 1. |
- Larsson, L. Arvid, et al.
(författare)
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Temperature and Magnetic Field Effects on the Transport Controlled Charge State of a Single Quantum Dot
- 2010
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Ingår i: NANOSCALE RESEARCH LETTERS. - : Springer Science Business Media. - 1931-7573 .- 1556-276X. ; 5:7, s. 1150-1155
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Tidskriftsartikel (refereegranskat)abstract
- Individual InAs/GaAs quantum dots are studied by micro-photoluminescence. By varying the strength of an applied external magnetic field and/or the temperature, it is demonstrated that the charge state of a single quantum dot can be tuned. This tuning effect is shown to be related to the in-plane electron and hole transport, prior to capture into the quantum dot, since the photo-excited carriers are primarily generated in the barrier.
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| 2. |
- Larsson, Mikael, 1982, et al.
(författare)
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Determination of the glass transition of powder samples using Dynamic Mechanic Analysis on compacts
- 2010
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Ingår i: Annual Transactions - The Nordic Rheology Society. - 1601-4057. ; 18, s. 59-64
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Dynamic Mechanic Analysis, DMA, is asensitive method to determine the glasstransition temperature (Tg) of materials.Several different sample geometries such asthree point bending, stretched films orcompressed cylinders, are commonly used.The Tg of a powder is related to its “stickypoint”, i.e. the temperature when the powderparticles interact instead of flowing freely.The determination of powder Tg is notstraightforward using DMA due to thelimiting geometry. Here it is demonstratedthat the Tg of powder samples canbe effectively and correctly determinedby DMA on compacts in compression mode,using a standard wedge shaped probe usuallyutilized in three point bend analysis. Theanalysis of compacts holds the benefits ofanalysing powder samples as received frommanufacturers, being relatively robust withregard to deformation as the materialbecomes rubbery, and enabling easy samplepreparation and handling.
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| 3. |
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| 4. |
- Larsson, Mikael, 1982, et al.
(författare)
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Effect of ethanol on the water permeability of controlled release films composed of ethyl cellulose and hydroxypropyl cellulose
- 2010
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Ingår i: European Journal of Pharmaceutics and Biopharmaceutics. - : Elsevier BV. - 1873-3441 .- 0939-6411. ; 76:3, s. 428-432
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Tidskriftsartikel (refereegranskat)abstract
- The robustness of controlled release formulations when co-ingested with alcohol is a current concern expressed by regulatory authorities, especially with regard to dose dumping. One such controlled release formulation commonly used is film coating composed of ethyl cellulose (EC) and hydroxypropyl cellulose (HPC). The aim of this study was to investigate how the presence of ethanol in the dissolution medium affects the water permeability of such films. Film samples were prepared in various EC–HPC compositions, and the effect of different ethanol concentrations in the dissolution medium on the permeability was studied using a modified Ussing chamber and tritiated water. It was found that the effect of ethanol on the film permeability varied depending on the composition of the films. The results were interpreted in terms of swelling of the EC in the films, where the swelling increased with increasing ethanol concentration. Thus, for films with low HPC content (non-interconnected pores), the water permeability of the films increased with increasing ethanol concentration as the diffusion through the ethyl cellulose increased due to swelling. However, for films with higher HPC content (having interconnected pores through the films), the permeability decreased, likely due to the swelling of the ethyl cellulose blocking the pores. The interpretation of the results was supported by dynamic mechanic analysis and SEM analysis.
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| 5. |
- Larsson, Mikael, 1982, et al.
(författare)
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High Performance Polysodium Acrylate Superabsorbents Utilizing Microfibrillated Cellulose to Augment Gel Properties
- 2010
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Ingår i: Soft Materials. - 1539-445X .- 1539-4468. ; 8:3, s. 207-225
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Tidskriftsartikel (refereegranskat)abstract
- Microfibrillated cellulose was utilized at low concentrations as a filler material, added prior to free radical polymerization, in cross-linked superabsorbent polysodium acrylate hydrogels. The effect of microfibrillated cellulose concentration on equilibrium swelling, shear modulus after synthesis, and shear modulus at equilibrium swelling was studied at different degree of cross-linking. For the characterization of the microfibrillated cellulose optical microscopy, atomic force microscopy, and transmittance analysis were used. The shear modulus of the samples was determined using uniaxial compression analysis. The swelling of the gels was determined using classical gravimetrical measurements. It was found that microfibrillated cellulose was highly efficient in increasing the shear modulus of the gels. Furthermore, the microfibrillated cellulose was found to have the same effect on the swelling and shear modulus at equilibrium swelling as the same mass of the conventional covalent cross-linker N,N'-methylenebisacrylamide (MBA), while in fact improving the fracture resistance of the gels. In conclusion, microfibrillated cellulose shows great potential as an additive to enhance the performance of soft materials.
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| 6. |
- Larsson, Mikael, 1982, et al.
(författare)
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The influence of HPMC substitution pattern on solid state properties
- 2010
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Ingår i: Carbohydrate Polymers. - : Elsevier BV. - 0144-8617 .- 1879-1344. ; 82:4, s. 1074-1081
-
Tidskriftsartikel (refereegranskat)abstract
- The solid-state properties were studied for different batches of hydroxypropyl methylcellulose (HPMC). The batches had similar chemical composition, but different degree of heterogeneity with regard to the distribution of the substituents along the polymer chains. The glass transition temperature, Tg, was analysed using a new developed method where dynamic mechanic analysis, DMA, was performed in compression mode on compacts, utilizing a wedge-shaped probe. The method was verified by conventional DMA on films. Molecular interactions were studied using FT-IR. In addition, the water vapour sorption was determined by gravimetric measurements and the plasticization by water vapour was studied on film samples using DMA. The results revealed a linear relationship between increasing Tg and increasing percent glucose liberated after enzyme hydrolysis. The percent glucose liberated can in turn be considered to account for both the heterogeneity of the substituents and the total degree of substitution. The results indicated that more heterogeneously substituted cellulose derivatives and derivates with a lower degree of substitution had stronger interactions between polymer chains. As expected from these results, some small difference in the plasticization by water vapour could be detected. However, no significant differences were found in molecular interactions using FT-IR or in the sorption of water vapour. The correlation between heterogeneity in the distribution of the substituents and Tg is of much interest as heterogeneously substituted batches of HPMC have been previously shown to exhibit very different behaviour in solution and in gelling tablets.
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| 7. |
- Larsson, Torsten, et al.
(författare)
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Intraosseous samples can be used for opioid measurements : An experimental study in the anaesthetized pig
- 2013
-
Ingår i: Scandinavian Journal of Clinical and Laboratory Investigation. - : Informa UK Limited. - 0036-5513 .- 1502-7686. ; 73:2, s. 102-106
-
Tidskriftsartikel (refereegranskat)abstract
- Aim.The intraosseous route provides access to the systemic circulation in an emergency situation when other forms of vascular access are unavailable and there is an urgent need for fluid or drug therapy. The intraosseous access has also been used for collecting samples for laboratory testing. A question that may arise in an unconscious or severely exhausted patient is whether this condition is caused by an unknown drug. We aimed to evaluate whether intraosseous samples could be used to measure opioids and to study the accuracy and precision of such measurements.Methods.Five healthy, anaesthetized pigs were treated with a continuous morphine infusion as part of the anaesthesia procedure. Samples for morphine testing were collected hourly for 6 h from two tibial intraosseous cannulae and a central venous catheter.Results. The differences in morphine concentrations between the two tibial intraosseous cannulae were less than 10% in 32/33 times. The values were also relatively stable over time.Conclusion.Our findings suggest that intraosseous samples can be used for the analysis of opioids if an IV route is not available.
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| 8. |
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| 9. |
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| 10. |
- Nordlund, Jessica, et al.
(författare)
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Genome-wide signatures of differential DNA methylation in pediatric acute lymphoblastic leukemia
- 2013
-
Ingår i: Genome Biology. - : Springer Science and Business Media LLC. - 1465-6906 .- 1474-760X. ; 14:9, s. r105-
-
Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Although aberrant DNA methylation has been observed previously in acute lymphoblastic leukemia (ALL), the patterns of differential methylation have not been comprehensively determined in all subtypes of ALL on a genome-wide scale. The relationship between DNA methylation, cytogenetic background, drug resistance and relapse in ALL is poorly understood.RESULTS:We surveyed the DNA methylation levels of 435,941 CpG sites in samples from 764 children at diagnosis of ALL and from 27 children at relapse. This survey uncovered four characteristic methylation signatures. First, compared with control blood cells, the methylomes of ALL cells shared 9,406 predominantly hypermethylated CpG sites, independent of cytogenetic background. Second, each cytogenetic subtype of ALL displayed a unique set of hyper- and hypomethylated CpG sites. The CpG sites that constituted these two signatures differed in their functional genomic enrichment to regions with marks of active or repressed chromatin. Third, we identified subtype-specific differential methylation in promoter and enhancer regions that were strongly correlated with gene expression. Fourth, a set of 6,612 CpG sites was predominantly hypermethylated in ALL cells at relapse, compared with matched samples at diagnosis. Analysis of relapse-free survival identified CpG sites with subtype-specific differential methylation that divided the patients into different risk groups, depending on their methylation status.CONCLUSIONS:Our results suggest an important biological role for DNA methylation in the differences between ALL subtypes and in their clinical outcome after treatment.
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| 11. |
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| 12. |
- Strandberg, Gunnar, et al.
(författare)
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Analysis of intraosseous samples using point of care technology : an experimental study in the anaesthetised pig
- 2012
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Ingår i: Resuscitation. - : Elsevier BV. - 0300-9572 .- 1873-1570. ; 83:11, s. 1381-1385
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND:Intraosseous access is an essential method in emergency medicine when other forms of vascular access are unavailable and there is an urgent need for fluid or drug therapy. A number of publications have discussed the suitability of using intraosseous access for laboratory testing. We aimed to further evaluate this issue and to study the accuracy and precision of intraosseous measurements.METHODS:Five healthy, anaesthetised pigs were instrumented with bilateral tibial intraosseous cannulae and an arterial catheter. Samples were collected hourly for 6h and analysed for blood gases, acid base status, haemoglobin and electrolytes using an I-Stat(®) point of care analyser.RESULTS: There was no clinically relevant difference between results from left and right intraosseous sites. The variability of the intraosseous sample values, measured as the coefficient of variance (CV), was maximally 11%, and smaller than for the arterial sample values for all variables except SO(2). For most variables, there seems to be some degree of systematic difference between intraosseous and arterial results. However, the direction of this difference seems to be predictable.CONCLUSION: Based on our findings in this animal model, cartridge based point of care instruments appear suitable for the analysis of intraosseous samples. The agreement between intraosseous and arterial analysis seems to be good enough for the method to be clinically useful. The precision, quantified in terms of CV, is at least as good for intraosseous as for arterial analysis. There is no clinically important difference between samples from left and right tibia, indicating a good reproducibility.
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| 13. |
- Aftab, Obaid, 1984-, et al.
(författare)
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Label-free detection and dynamic monitoring of drug-induced intracellular vesicle formation enabled using a 2-dimensional matched filter
- 2014
-
Ingår i: Autophagy. - : Informa UK Limited. - 1554-8627 .- 1554-8635. ; 10:1, s. 57-69
-
Tidskriftsartikel (refereegranskat)abstract
- Analysis of vesicle formation and degradation is a central issue in autophagy research and microscopy imaging is revolutionizing the study of such dynamic events inside living cells. A limiting factor is the need for labeling techniques that are labor intensive, expensive, and not always completely reliable. To enable label-free analyses we introduced a generic computational algorithm, the label-free vesicle detector (LFVD), which relies on a matched filter designed to identify circular vesicles within cells using only phase-contrast microscopy images. First, the usefulness of the LFVD is illustrated by presenting successful detections of autophagy modulating drugs found by analyzing the human colorectal carcinoma cell line HCT116 exposed to each substance among 1266 pharmacologically active compounds. Some top hits were characterized with respect to their activity as autophagy modulators using independent in vitro labeling of acidic organelles, detection of LC3-II protein, and analysis of the autophagic flux. Selected detection results for 2 additional cell lines (DLD1 and RKO) demonstrate the generality of the method. In a second experiment, label-free monitoring of dose-dependent vesicle formation kinetics is demonstrated by recorded detection of vesicles over time at different drug concentrations. In conclusion, label-free detection and dynamic monitoring of vesicle formation during autophagy is enabled using the LFVD approach introduced.
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| 14. |
- Aftab, Obaid, 1984-, et al.
(författare)
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Label free high throughput screening for apoptosis inducing chemicals using time-lapse microscopy signal processing
- 2014
-
Ingår i: Apoptosis (London). - : Springer Science and Business Media LLC. - 1360-8185 .- 1573-675X. ; 19:9, s. 1411-1418
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Tidskriftsartikel (refereegranskat)abstract
- Label free time-lapse microscopy has opened a new avenue to the study of time evolving events in living cells. When combined with automated image analysis it provides a powerful tool that enables automated large-scale spatiotemporal quantification at the cell population level. Very few attempts, however, have been reported regarding the design of image analysis algorithms dedicated to the detection of apoptotic cells in such time-lapse microscopy images. In particular, none of the reported attempts is based on sufficiently fast signal processing algorithms to enable large-scale detection of apoptosis within hours/days without access to high-end computers. Here we show that it is indeed possible to successfully detect chemically induced apoptosis by applying a two-dimensional linear matched filter tailored to the detection of objects with the typical features of an apoptotic cell in phase-contrast images. First a set of recorded computational detections of apoptosis was validated by comparison with apoptosis specific caspase activity readouts obtained via a fluorescence based assay. Then a large screen encompassing 2,866 drug like compounds was performed using the human colorectal carcinoma cell line HCT116. In addition to many well known inducers (positive controls) the screening resulted in the detection of two compounds here reported for the first time to induce apoptosis.
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| 15. |
- Ahlinder, Jon, et al.
(författare)
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Increased knowledge of Francisella genus diversity highlights the benefits of optimised DNA-based assays
- 2012
-
Ingår i: BMC Microbiology. - : Springer Science and Business Media LLC. - 1471-2180. ; 12, s. 220-
-
Tidskriftsartikel (refereegranskat)abstract
- Background: Recent advances in sequencing technologies offer promising tools for generating large numbers of genomes, larger typing databases and improved mapping of environmental bacterial diversity. However, DNA-based methods for the detection of Francisella were developed with limited knowledge about genetic diversity. This, together with the high sequence identity between several Francisella species, means there is a high risk of false identification and detection of the highly virulent pathogen Francisella tularensis. Moreover, phylogenetic reconstructions using single or limited numbers of marker sequences often result in incorrect tree topologies and inferred evolutionary distances. The recent growth in publicly accessible whole-genome sequences now allows evaluation of published genetic markers to determine optimal combinations of markers that minimise both time and laboratory costs. Results: In the present study, we evaluated 38 previously published DNA markers and the corresponding PCR primers against 42 genomes representing the currently known diversity of the genus Francisella. The results highlight that PCR assays for Francisella tularensis are often complicated by low specificity, resulting in a high probability of false positives. A method to select a set of one to seven markers for obtaining optimal phylogenetic resolution or diagnostic accuracy is presented. Conclusions: Current multiple-locus sequence-typing systems and detection assays of Francisella, could be improved by redesigning some of the primers and reselecting typing markers. The use of only a few optimally selected sequence-typing markers allows construction of phylogenetic topologies with almost the same accuracy as topologies based on whole-genome sequences.
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| 16. |
-
Aktörer och marknader i omvandling : studier i företagandets historia tillägnade Kersti Ullenhag
- 2011
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Samlingsverk (redaktörskap) (övrigt vetenskapligt/konstnärligt)abstract
- This book is a Festschrift to professor emerita Kersti Ullenhag in honour of her 75th birthday. Kersti Ullenhag has been a teacher and researcher in economic history at Uppsala University since the mid 1960’s. Her research has focused on different aspects of business history, often combining micro-oriented empirical case studies with Schumpeterian theories on entrepreneurship. In 19 chapters this book deals with research topics such as the roots of business history,political economy, business and entrepreneurship, the development of financial markets and gender perspectives in business and society.
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| 17. |
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| 18. |
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| 19. |
- Andaloussi, Mounir, et al.
(författare)
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Design, Synthesis, and X-ray Crystallographic Studies of alpha-Aryl Substituted Fosmidomycin Analogues as Inhibitors of Mycobacterium tuberculosis 1-Deoxy-D-xylulose 5-Phosphate Reductoisomerase
- 2011
-
Ingår i: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 0022-2623 .- 1520-4804. ; 54:14, s. 4964-4976
-
Tidskriftsartikel (refereegranskat)abstract
- The natural antibiotic fosmidomycin acts via inhibition of 1-deoxy-D-xylulose 5-phosphate reductoisomerase (DXR), an essential enzyme in the non-mevalonate pathway of isoprenoid biosynthesis. Fosmidomycin is active on Mycobacterium tuberculosis DXR (MtDXR), but it lacks antibacterial activity probably because of poor uptake. alpha-Aryl substituted fosmidomycin analogues have more favorable physicochemical properties and are also more active in inhibiting malaria parasite growth. We have solved crystal structures of MtDXR in complex with 3,4-dichlorophenyl substituted fosmidomycin analogues; these show important differences compared to our previously described forsmidomycin-DXR complex. Our best inhibitor has an IC(50) = 0.15 mu M on MtDXR but still lacked activity in a mycobacterial growth assay (MIC > 32 mu g/mL). The combined results, however, provide insights into how DXR accommodates the new inhibitors and serve as an excellent starting point for the design of other novel and more potent inhibitors, particularly against pathogens where uptake is less of a problem, such as the malaria parasite.
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| 20. |
- Andersson, Helene, 1983, et al.
(författare)
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Effects of molecular weight on permeability and microstructure of mixed ethyl-hydroxypropyl-cellulose films
- 2013
-
Ingår i: European Journal of Pharmaceutical Sciences. - : Elsevier BV. - 0928-0987 .- 1879-0720. ; 48:1-2, s. 240-248
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Tidskriftsartikel (refereegranskat)abstract
- Films of ethyl cellulose (EC) and water-soluble hydroxypropyl cellulose (HPC) can be used for extended release coatings in oral formulations. The permeability and microstructure of free EC/HPC films with 30% w/w HPC were studied to investigate effects of EC molecular weight. Phase separation during film spraying and subsequent HPC leaching after immersion in aqueous media cause pore formation in such films. It was found that sprayed films were porous throughout the bulk of the films after water immersion. The molecular weight affected HPC leaching, pore morphology and film permeability; increasing the molecular weight resulted in decreasing permeability. A model to distinguish the major factors contributing to diffusion retardation in porous films showed that the trend in permeability was determined predominantly by factors associated with the geometry and arrangement of pores, independent of the diffusing species. The film with the highest molecular weight did, however, show an additional contribution from pore wall/permeant interactions. In addition, rapid drying and increasing molecular weight resulted in smaller pores, which suggest that phase separation kinetics affects the final microstructure of EC/HPC films. Thus, the molecular weight influences the microstructural features of pores, which are crucial for mass transport in EC/HPC films.
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| 21. |
- Andersson, Helene, et al.
(författare)
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Effects of Molecular Weight on Phase Separated Coatings for Controlled Release of Drugs
- 2013
-
Ingår i: Annual Transactions of the Nordic Rheology Society. ; , s. 249-
-
Tidskriftsartikel (refereegranskat)abstract
- Phase separated films with controlled porosity were made from ethyl cellulose (EC) and 30% w/w hydroxypropyl cellulose (HPC). The molecular weight of EC can be used to modify the mass transfer rate through coatings by effects on microstructure of the film. Processing conditions are, however, affected by the solution rheology, which could influence the film quality when using different molecular weights.
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| 22. |
- Andersson, Patrik U, 1970, et al.
(författare)
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Formation of Highly Rovibrationally Excited Ammonia from Dissociative Recombination of NH4
- 2010
-
Ingår i: Journal of Physical Chemistry Letters. - : American Chemical Society (ACS). - 1948-7185. ; 1:17, s. 2519-2523
-
Tidskriftsartikel (refereegranskat)abstract
- The internal energy distribution of ammonia formed in the dissociative recombination (DR) of NH4+ with electrons has been studied by an imaging technique at the ion storage ring CRYRING. The DR process resulted in the formation of NH3 + H (0.90 ± 0.01), with minor contributions from channels producing NH2 + H2 (0.05 ± 0.01) and NH2 + 2H (0.04 ± 0.02). The formed NH3 molecules were highly internally excited, with a mean rovibrational energy of 3.3 ± 0.4 eV, which corresponds to 70% of the energy released in the neutralization process. The internal energy distribution was semiquantitatively reproduced by ab initio direct dynamics simulations, and the calculations suggested that the NH3 molecules are highly vibrationally excited while rotational excitation is limited. The high internal excitation and the translational energy of NH3 and H will influence their subsequent reactivity, an aspect that should be taken into account when developing detailed models of the interstellar medium and ammonia-containing plasmas.
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| 23. |
- Andersson, Sarah, et al.
(författare)
-
Malmbanan Diaries
- 2010
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This booklet is a report for a case study visit during four day field trip, a group of nine PhD students and their supervisors – all part of the National Research School for Architecture and Planning in the Urban Landscape, APULA – set out to explore what may be considered the outback of Western Europe’s conurbations, the transnational region of Kiruna -Narvik.Both “remote” and “resourceful”, “threatened” and “thriving” (equally relative notions), this region seemed to offer possibilities to reflect upon many of the current tendencies influencing contemporary planning practice and research.
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| 24. |
- Anrup, Roland, et al.
(författare)
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Centrala universitetsvärden hotas av bolagiseringsidén
- 2013
-
Ingår i: Dagens nyheter. - 1101-2447.
-
Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Högskolestiftelser. Förslaget att driva svenska universitet i stiftelseform öppnar för bolagisering. Men det är ingen riktig utredning, utan en politisk pamflett utan eftertanke. Privatisering av universitet hotar både oberoendet, forskningskvaliteten och samhällsnyttan, skriver 36 forskare vid svenska högskolor och universitet.
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| 25. |
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| 26. |
- Berrah, Nora, et al.
(författare)
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Double-core-hole spectroscopy for chemical analysis with an intense X-ray femtosecond laser
- 2011
-
Ingår i: Proceedings of the National Academy of Sciences of the United States of America. - : Proceedings of the National Academy of Sciences. - 0027-8424 .- 1091-6490. ; 108:41, s. 16912-16915
-
Tidskriftsartikel (refereegranskat)abstract
- Theory predicts that double-core-hole (DCH) spectroscopy can provide a new powerful means of differentiating between similar chemical systems with a sensitivity not hitherto possible. Although DCH ionization on a single site in molecules was recently measured with double-and single-photon absorption, double-core holes with single vacancies on two different sites, allowing unambiguous chemical analysis, have remained elusive. Here we report that direct observation of double-core holes with single vacancies on two different sites produced via sequential two-photon absorption, using short, intense X-ray pulses from the Linac Coherent Light Source free-electron laser and compare it with theoretical modeling. The observation of DCH states, which exhibit a unique signature, and agreement with theory proves the feasibility of the method. Our findings exploit the ultrashort pulse duration of the free-electron laser to eject two core electrons on a time scale comparable to that of Auger decay and demonstrate possible future X-ray control of physical inner-shell processes.
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| 27. |
- Birdsell, Dawn N, et al.
(författare)
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Francisella tularensis subsp. tularensis group A.I, United States
- 2014
-
Ingår i: Emerging Infectious Diseases. - : Centers for Disease Control and Prevention (CDC). - 1080-6040 .- 1080-6059. ; 20:5, s. 861-865
-
Tidskriftsartikel (refereegranskat)abstract
- We used whole-genome analysis and subsequent characterization of geographically diverse strains using new genetic signatures to identify distinct subgroups within Francisella tularensis subsp. tularensis group A.I: A.I.3, A.I.8, and A.I.12. These subgroups exhibit complex phylogeographic patterns within North America. The widest distribution was observed for A.I.12, which suggests an adaptive advantage.
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| 28. |
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| 29. |
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| 30. |
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| 31. |
- Bollen, Math, et al.
(författare)
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Harmonic emission from installations with energy-efficient lighting
- 2011
-
Ingår i: Proceeding of the International Conference on Electrical Power Quality and Utilisation, EPQU. - Piscataway, NJ : IEEE Communications Society. - 9781467303798 ; , s. 797-802
-
Konferensbidrag (refereegranskat)abstract
- This paper presents the results from a number of measurements of the harmonic emission from installations that contain a large number of energy-efficient lamps. Two of the measurements concern the replacement of incandescent lamps with CFL and LED; the other measurement concerns an installation with up to 48 fluorescent lamps with high-frequency ballasts. The paper also contains a discussion on why the (total) power factor is not a good measure to quantify the performance of lamps or installations containing large numbers of lamps
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| 32. |
- Borking, Kjell, et al.
(författare)
-
Transcending Business Intelligence
- 2011. - 1
-
Bok (populärvet., debatt m.m.)abstract
- How on Earth did this happen? The question is not infrequent, but more to the point, it?s unnecessary. It arises because in many cases people haven?t thought things through beforehand. Yes, sometimes people can be unlucky, but far from every time that things go awry; bad luck is never so consistent - by definition. Thinking things through properly beforehand might seem a fairly obvious requirement for making a good decision, but startlingly often, even critical decisions are made without any in depth analysis. Well, there may have been some background data lying around somewhere, but not much is done with it. Though it's easy to blame authoritarian leadership or the like, poor decision making is far more usually due to not really knowing what to do with the available information, whether it's sufficient and what else needs to be known There?s nothing weird or idiotic about today?s decision makers, but there often is about the tools and methods available to them. It would be more accurate to say that many decision makers have been lead astray regarding their remit and capacity, but fortunately with structured decision processes they can be guided back on track far more easily than had they been as dim- witted as some of their decisions would indicate.Businesses introduce various BI solutions both timely and untimely, but what most of them don't have is any kind of methodology by which to deal with decisions. With no processes, knowledge, techniques or tools, they soon come to grief. Happily this is fairly easy to remedy.Decision processes and decision methods can be greatly improved. In this book we simply explain how to go about it.
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| 33. |
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| 34. |
- Brattsand, Göran, et al.
(författare)
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Equalis/SFKK rekommenderar harmonisering av enheter vid hormonbestämningar -Något också för Norden?
- 2012
-
Ingår i: Klinisk Biokemi i Norden. - 1101-2013. ; 24:4, s. 20-27
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Tidskriftsartikel (refereegranskat)abstract
- Equalis och Svensk Förening för Klinisk Kemi (SFKK) rekommenderar att de kliniska laboratorierna i Sverige använder enhetliga måttenheter vid hormonbestämningar för ökad jämförbarhet och patientsäkerhet. Vid analys i serum eller plasma med nuvarande metoder rekommenderas följande enheter:• Adrenokortikotropt hormon (ACTH): pmol/L• Insulin: mIE/L• Parathormon (PTH): pmol/L• Prolaktin: mIE/L• Tillväxthormon (GH): μg/L• Östradiol: pmol/L• Aldosteron: pmol/L• Reninkoncentration: mIE/L
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| 35. |
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| 36. |
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| 37. |
- Castegren, Markus, et al.
(författare)
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Differences in Organ Dysfunction in Endotoxin Tolerant Pigs Under Intensive Care Exposed to a Second Hit of Endotoxin
- 2012
-
Ingår i: Shock. - 1073-2322 .- 1540-0514. ; 37:5, s. 501-510
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Tidskriftsartikel (refereegranskat)abstract
- Endotoxin tolerance is a well-studied phenomenon associated with a reduced inflammatory response. In the switch from an inflammatory to an anti-inflammatory response in clinical sepsis the concept of endotoxin tolerance is of obvious interest. However, only limited data exist regarding the effect of endotoxin tolerance on organ dysfunction and, therefore, this was investigated in a porcine intensive care sepsis model. Twenty-seven healthy pigs, including nine control animals, were included in the study. Twelve pigs pre-exposed to 24 h of intravenous endotoxin infusion and intensive care and six unexposed pigs were given either a high- or low-dose endotoxin challenge for 6 h. Inflammatory, circulatory, hypoperfusion and organ dysfunction parameters were followed. The inflammatory responses as well as parameters representing circulation, hypoperfusion, cardiac and renal function were all markedly attenuated in animals pre-exposed to endotoxin and intensive care as compared with animals not pre-exposed. In animals pre-exposed to endotoxin and given the high-dose of endotoxin challenge, deterioration in pulmonary function was equal to or even worse than in animals not pre-exposed.In contrast to the overall protective effect of endotoxin tolerance observed in other organ systems, the lungs of endotoxin tolerant animals demonstrated an increased responsiveness to high-dose endotoxin challenge.
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| 38. |
- Chompoobutrgool, Yuwa, 1984-
(författare)
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Concepts for Power System Small Signal Stability Analysis and Feedback Control Design Considering Synchrophasor Measurements
- 2012
-
Licentiatavhandling (övrigt vetenskapligt/konstnärligt)abstract
- In the Nordic power network, the existence of poorly damped low-frequency inter-area oscillations (LFIOs) has long affected stability constraints, and thereby, limited power transfer capacity. Adequate damping of inter-area modes is, thus, necessary to secure system operation and ensure system reliability while increasing power transfers. Power system stabilizers (PSS) is a prevalent means to enhance the damping of such modes. With the advent of phasor measurement units (PMUs), it is expected that wide-area damping control (WADC), that is, PSS control using wide-area measurements obtained from PMUs, would effectively improve damping performance in the Nordic grid, as well as other synchronous interconnected systems. Numerous research has investigated one ``branch'' of the problem, that is, PSS design using various control schemes. Before addressing the issue of controller design, it is important to focus on developing proper understanding of the ``root'' of the problem: system-wide oscillations, their nature, behavior and consequences. This understanding must provide new insight on the use of PMUs for feedback control of LFIOs. The aim of this thesis is, therefore, to lay important concepts necessary for the study of power system small signal stability analysis that considers the availability of synchrophasors as a solid foundation for further development and implementation of ideas and related applications. Particularly in this study, the focus is on the application addressed damping controller design and implementation. After a literature review on the important elements for wide-area damping control (WADC), the thesis continues with classical small signal stability analysis of an equivalent Nordic model; namely, the KTH-NORDIC32 which is used as a test system throughout the thesis. The system's inter-area oscillations are identified and a sensitivity analysis of the network variables directly measured by synchrophasors is evaluated. The concept of network modeshapes, which is used to relate the dynamical behavior of power systems to the features of inter-area modes, is elaborated. Furthermore, this network modeshape concept is used to determine dominant inter-area oscillation paths, the passageways containing the highest content of the inter-area oscillations. The dominant inter-area paths are illustrated with the test system. The degree of persistence of dominant paths in the study system is determined through contingency studies. The properties of the dominant paths are used to construct feedback signals as input to the PSS. Finally, to exemplify the use of the dominant inter-area path concept for damping control, the constructed feedback signals are implemented in a PSS modulating the AVR error signal of a generator on an equivalent two-area model, and compared with that of conventional speed signals.
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| 39. |
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| 40. |
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| 41. |
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| 42. |
- Colli, Andrea, et al.
(författare)
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Family business and business history : An example of comparative research
- 2014
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Ingår i: Business History. - : Informa UK Limited. - 0007-6791 .- 1743-7938. ; 56:1, s. 37-53
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Tidskriftsartikel (refereegranskat)abstract
- This paper deals with one of the pillars of contemporary business history - the use of cross-national comparisons. Besides the longitudinal, the comparative perspective is a crucial dimension of business and economic history research. During the last decades several attempts have been made to illustrate the process of development and structuring of national markets and corporations both currently and in a historical perspective, through the use of a comparative method. This paper aims to point out the possibilities and problems with this approach. It especially highlights the role of institutional factors and changes as important determinants for national development and as obstacles for good comparative exercises. It also discusses the role of functional and coherent definitions in comparative research and the problems connected with data collection and analysis. The main research question is how cross-national comparisons can help us develop business history research further. A comparison between family firms in Italy and Sweden shows that the development of family business in these two countries exhibited extensive similarities during the early decades of the twentieth century. However after World War II the two countries became more diversified in terms of their industrial structure. While Swedish family firms became an important part of national big business, Italian family businesses developed into smaller and more flexible organisations. Thus, today in Sweden several family-owned and controlled firms are among the largest in the country, particularly in capital- and technology-intensive industries. Italian family firms, even if present among the largest in the country, are largely in industries other than high tech, and show a degree of organisational sophistication inferior to their Swedish counterparts. This paper discusses the driving forces behind this development, showing how the explicit use of the comparative, longitudinal approach can highlight the patterns of convergence and divergence across national business models.
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| 43. |
- Dahlén, Marianne, et al.
(författare)
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Business history and legal history
- 2014
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Ingår i: Business History. - : Informa UK Limited. - 0007-6791 .- 1743-7938. ; 56:1, s. 54-70
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Tidskriftsartikel (refereegranskat)abstract
- The relation between corporations, the market and the legal framework is crucial for understanding the development and function of the modern enterprise. The legal framework determines - and is determined by - the development of economic life, nationally, regionally and internationally. Business historians have often used legal material in their studies, however usually from a strict business history perspective. Drawing also from legal theory and method can contribute to a deeper understanding of the interplay between law and business, for example in terms of concepts such as hard law', soft law' and co-regulation'. In the same way, legal scholarship has dealt with business law, but would benefit from borrowing tools from the business history toolkit. Institutional theory is one of the pillars of this article, together with theories and methods focusing on law as a non-stable, multi-layer system with porous borders. The analysis starts with a discussion of the relationship between business history and legal history from a theoretical and methodological perspective. It continues with two cases at the borderland of business history and legal history: finance and fashion. Both cases serve as illustrations for the different roles that the state can assume as well as the different methodological approaches that are needed for an analysis of the state activities and the interaction between state, market and business.
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| 44. |
- Danielson, Mats, et al.
(författare)
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Generalised Risk Constraints in Decision Trees with Second-Order Probabilities
- 2012
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Ingår i: Advances in Economics, Risk Management, Political and Law Science. - : World Scientific and Engineering Academy and Society. - 9781618041234 ; , s. 376-383
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Konferensbidrag (refereegranskat)abstract
- Recently, representations and methods analysing decision problems where probabilities and values (utilities) are associated with belief distributions over them (second order representations) have been suggested. Inthis paper we present an approach to how imprecise information can be modelled by means of second-order distri-butions and how a risk evaluation process can be elaborated by integrating procedures for numerically impreciseprobabilities and utilities. We discuss some shortcomings in the use of the principle of maximising the expectedutility and of utility theory in general, and offer remedies by the introduction of supplementary decision rules basedon a concept of risk constraints taking advantage of second-order distributions.
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| 45. |
- Danielson, Mats, et al.
(författare)
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Transparent Public Decision Making : Discussion and Case Study in Sweden
- 2010
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Ingår i: e-Democracy. - Dordrecht : Springer. - 9789048190447 - 9789048190454 ; , s. 263-281
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The Swedish city of Örebro has since long faced complex problems with poor water quality in a local river. This problem is a typical example of a regional decision problem, since there are several different stakeholders that might be affected, and there are different views on the need for, and effect of, different measures. The problems also strongly relate to the environmental condition of the river and involve other municipalities as well. In this chapter, we describe how to address this problem using an implementation of a systematic democratic deci-sion process for enhancing the transparency and the decision quality in itself. The process is in conformity with common democratic processes, but with higher em-phasis on accuracy and precision and on the interaction between civil servants and decision makers. A main issue here is to clearly separate the various views in-volved in these processes from the actual facts and, at the same time, facilitate input from various stakeholders. Therefore, we allow for modelling of outcomes based on different preferences and facilitate an elicitation process where views are extracted and combined with basic data from the background investigations preceding the decision. The process is divided into two stages. The first one is em-phasized in this chapter and concerns the internal democracy, i.e. the formulation and refinement of the original and extended decision problems and the interaction between politicians and civil servants, while the second stage deals with the external democracy, i.e. the communication with the public, where communication channels directed towards citizens will be formed.
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| 46. |
- Danielson, Mats, et al.
(författare)
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Weighting Under Ambiguous Preferences and Imprecise Differences in a Cardinal Rank Ordering Process
- 2014
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Ingår i: International Journal of Computational Intelligence Systems. - : Springer Science and Business Media LLC. - 1875-6891 .- 1875-6883. ; 7:S1, s. 105-112
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Tidskriftsartikel (refereegranskat)abstract
- The limited amount of good tools for supporting elicitation of preference information in multi-criteria decision analysis (MCDA) causes practical problem. In our experiences, this can be remedied by allowing more relaxed input statements from decision-makers, causing the elicitation process to be less cognitively demanding. Furthermore, it should not be too time consuming and must be able to actually use of the information the decision-maker is able to supply. In this paper, we propose a useful weight elicitation method for MAVT/MAUT decision making, which builds on the ideas of rank-order methods, but increases the precision by adding numerically imprecise cardinal information as well.
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| 47. |
- Drca, Nikola, et al.
(författare)
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Atrial fibrillation is associated with different levels of physical activity levels at different ages in men
- 2014
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Ingår i: Heart. - : BMJ PUBLISHING GROUP. - 1355-6037 .- 1468-201X. ; 100:13, s. 1037-1042
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Tidskriftsartikel (refereegranskat)abstract
- Objective This study examines the influence of physical activity at different ages and of different types, on the risk of developing atrial fibrillation (AF) in a large cohort of Swedish men. Methods Information about physical activity was obtained from 44 410 AF-free men, aged 45-79 years (mean age=60), who had completed a self-administered questionnaire at baseline in 1997. Participants reported retrospectively their time spent on leisure-time exercise and on walking or bicycling throughout their lifetime (at 15, 30 and 50 years of age, and at baseline (mean age=60)). Participants were followed-up in the Swedish National Inpatient Register for ascertainment of AF. Cox proportional hazards regression models were used to estimate relative risks (RR) with 95% CIs, adjusted for potential confounders. Results During a median follow-up of 12 years, 4568 cases of AF were diagnosed. We observed a RR of 1.19 (95% CI 1.05 to 1.36) of developing AF in men who at the age of 30 years had exercised for >5 h/week compared with <1 h/week. The risk was even higher (RR 1.49, 95% CI 1.14 to 1.95) among the men who exercised >5 h/week at age 30 and quit exercising later in life (<1 h/week at baseline). Walking/bicycling at baseline was inversely associated with risk of AF (RR 0.87, 95% CI 0.77 to 0.97 for >1 h/day vs almost never) and the association was similar after excluding men with previous coronary heart disease or heart failure at baseline (corresponding RR 0.88, 95% CI 0.77 to 0.998). Conclusions Leisure-time exercise at younger age is associated with an increased risk of AF, whereas walking/bicycling at older age is associated with a decreased risk.
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| 48. |
- Ebadat, Afrooz, et al.
(författare)
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Application Set Approximation in Optimal Input Design for Model Predictive Control
- 2014
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Ingår i: 2014 European Control Conference (ECC). - 9783952426913 ; , s. 744-749
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Konferensbidrag (refereegranskat)abstract
- This contribution considers one central aspect of experiment design in system identification, namely application set approximation. When a control design is based on an estimated model, the achievable performance is related to the quality of the estimate. The degradation in control performance due to plant-modeling missmatch is quantified by an application cost function. A convex approximation of the set of models that satisfy the control specification is typically required in optimal input design. The standard approach is to use a quadratic approximation of the application cost function, where the main computational effort is to find the corresponding Hessian matrix. Our main contribution is an alternative approach for this problem, which uses the structure of the underlying optimal control problem to considerably reduce the computations needed to find the application set. This technique allows the use of applications oriented input design for MPC on much more complex plants. The approach is numerically evaluated on a distillation control problem.
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| 49. |
- Edbom, T, et al.
(författare)
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High sense of coherence in adolescence is a protective factor in the longitudinal development of ADHD symptoms
- 2010
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Ingår i: Scandinavian Journal of Caring Sciences. - : Wiley. - 0283-9318 .- 1471-6712. ; 24:3, s. 541-547
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Tidskriftsartikel (refereegranskat)abstract
- The key feature of salutogenesis is that good health can be directly sustained by positive factors. The Sense of Coherence (SOC) scale was developed by Antonovsky as a measure related to the concept of salutogenesis including aspects of comprehensibility, manageability and meaningfulness.Aim: The aim was to investigate whether Sense of Coherence can serve as a salutogenetic factor modifying the long-term development of Attention Deficit Hyperactivity Disorder (ADHD) Symptoms.Subjects and methods: Twin study of Child and Adolescent Development (TCHAD) is a longitudinal study of all twin pairs born in Sweden between May 1985 and December 1986. The present project is a sub-sample of 312 individuals (135 boys and 177 girls). At 16 years of age, the young persons and their parents were interviewed with K-SADS especially symptoms of ADHD. The young person also completed the SOC questionnaire. At 21 years of age, the young person completed a questionnaire about symptoms of ADHD.Findings: Higher (worse) ADHD scores at 16 years of age were associated with higher (worse) ADHD scores at 21 years of age. However, this relationship was stronger for lower (worse) SOC. A higher (better) SOC at 16 years was associated with lower (better) ADHD at 21 years and this relationship was stronger for higher (worse) ADHD at 16 years.Conclusion: A high Sense of Coherence in adolescence was a protective factor for the long-term development of ADHD.
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| 50. |
- Eggertsen, Per-Anders, 1981, et al.
(författare)
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A comprehenisve analysis of benchmark 4 : Pre-strain effect on springback of 2D draw bending
- 2011
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Ingår i: AIP Conference Proceedings. - Seoul : AIP. - 0094-243X .- 1551-7616. ; , s. 1064-1071
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Konferensbidrag (refereegranskat)abstract
- In order to be able to form high strength steels with low ductility, multi-step forming processes are becoming more common. Benchmark 4 of the NUMISHEET 2011 conference is an attempt to imitate such a process. A DP780 steel sheet with 1.4 mm thickness is considered. In order to understand the pre-strain effect on subsequent forming and springback, a 2D draw-bending is considered. Two cases are studied: one without prestrain and one with 8% pre-stretching. The draw-bending model is identical to the "U-bend" problem of the NUMISHEET'93 conference. The purpose of the benchmark problem is to evaluate the capability of modern FE-methods to simulate the forming and springback of these kinds of problems. The authors of this article have previously made exhaustive studies on material modeling in applications to sheet metal forming and springback problems, [1],[2],[3]. Models for kinematic hardening, anisotropic yield conditions, and elastic stiffness reduction have been investigated. Also procedures for material characterization have been studied. The material model that mainly has been used in the current study is based on the Banabic BBC2005 yield criterion, and a modified version of the Yoshida-Uemori model for cyclic hardening. This model, like a number of other models, has been implemented as User Subroutines in LS-DYNA. The effects of various aspects of material modeling will be demonstrated in connection to the current benchmark problems. The provided material data for the current benchmark problem are not complete in all respects. In order to be able to perform the current simulations, the authors have been forced to introduce a few additional assumptions. The effects of these assumptions will also be discussed. © 2011 American Institute of Physics.
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