| 671. |
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| 672. |
- Lindbom, John, 1960-, et al.
(författare)
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Exposure to wear particles generated from studded tires and pavement induces inflammatory cytokine release from human macrophages
- 2006
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Ingår i: Chemical Research in Toxicology. - : American Chemical Society (ACS). - 0893-228X .- 1520-5010. ; 19:4, s. 521-530
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Tidskriftsartikel (refereegranskat)abstract
- Health risks associated with exposure to airborne paniculate matter (PM) have been shown epidemiologically as well as experimentally, pointing to both respiratory and cardiovascular effects. Lately, wear particles generated from traffic have been recognized to be a major contributing source to the overall particle load, especially in the Nordic countries were studded tires are used. In this work, we investigated the inflammatory effect of PM10 generated from the wear of studded tires on two different types of pavement. As comparison, we also investigated PM10 from a traffic-intensive street, a subway station, and diesel exhaust particles (DEP). Human monocyte-derived macrophages, nasal epithelial cells (RPMI 2650), and bronchial epithelial cells (BEAS-2B) were exposed to the different types of particles, and the secretion of IL-6, IL-8, IL-10, and TNF-α into the culture medium was measured. The results show a significant release of cytokines from macrophages after exposure for all types of particles. When particles generated from asphalt/granite pavement were compared to asphalt/quartzite pavement, the granite pavement had a significantly higher capacity to induce the release of cytokines. The granite pavement particles induced cytokine release at the same magnitude as the street particles did, which was higher than what particles from both a subway station and DEP did. Exposure of epithelial cells to PM 10 resulted in a significant increase of TNF-α secreted from BEAS-2B cells for all types of particles used (DEP was not tested), and the highest levels were induced by subway particles. None of the particle types were able to evoke detectable cytokine release from RPMI 2650 cells. The results indicate that PM10 generated by the wear of studded tires on the street surface is a large contributor to the cytokine-releasing ability of particles in traffic-intensive areas and that the type of pavement used is important for the level of this contribution. Furthermore, the airway inflammatory potential of wear particles from tires and pavement might be of a greater magnitude than that of DEP.
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| 673. |
- Lindbom, John, 1960-, et al.
(författare)
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Wear particles generated from studded tires and pavement induces inflammatory reactions in mouse macrophage cells
- 2007
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Ingår i: Chemical Research in Toxicology. - : American Chemical Society (ACS). - 0893-228X .- 1520-5010. ; 20:6, s. 937-946
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Tidskriftsartikel (refereegranskat)abstract
- Health risks associated with exposure to airborne particulate matter (PM) have been shown epidemiologically as well as experimentally, pointing to both respiratory and cardiovascular effects. These health risks are of increasing concern in society, and to protect public health, a clarification of the toxic properties of particles from different sources is of importance. Lately, wear particles generated from traffic have been recognized as a major contributing source to the overall particle load, especially in the Nordic countries where studded tires are used. The aim of this study was to further investigate and compare the ability to induce inflammatory mediators of different traffic-related wear particles collected from an urban street, a subway station, and studded tire-pavement wear. Inflammatory effects were measured as induction of nitric oxide (NO), IL-6, TNF-α, arachidonic acid (AA), and lipid peroxidation after exposure of the murine macrophage like cell line RAW 264.7. In addition, the redox potential of the particles was measured in a cell-free system. The results show that all particles tested induce IL-6, TNF-α, and NO, and those from the urban street were the most potent ones. In contrast, particles collected from a subway station were most potent to induce lipid peroxidation, A A release, and formation of ROS. Particles from studded tire-pavement wear, generated using a road simulator, were able to induce inflammatory cytokines, NO, lipid peroxidation, and ROS formation. Interestingly, particles generated from pavement containing granite as the main stone material were more potent than those generated from pavement containing quartzite as the main stone material.
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| 674. |
- Linde, Mats, et al.
(författare)
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Effects of changed soil conditions on the mobility of trace metals in moderately contaminated urban soils
- 2007
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Ingår i: Water, Air and Soil Pollution. - : Springer Science and Business Media LLC. - 0049-6979 .- 1573-2932. ; 183:04-jan, s. 69-83
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Tidskriftsartikel (refereegranskat)abstract
- Changes in the soil chemical environment can be expected to increase the leaching of trace metals bound in soils. In this study the mobility of trace metals was monitored in a column experiment for two contaminated urban soils. Four different treatments were used (i.e. rain, acid rain, salt and bark). Leachates were analysed for pH, dissolved organic carbon (DOC) and for seven trace metals (cadmium (Cd), chromium (Cr), copper (Cu), mercury (Hg), nickel (Ni), lead (Pb) and zinc (Zn)). The salt treatment produced the lowest pH values (between 5 and 6) in the effluent whereas the DOC concentration was largest in the bark treatment (40-140 mg L-1) and smallest in the salt and acid treatments (7-40 mg L-1). Cadmium, Ni and Zn were mainly mobilised in the salt treatment, whereas the bark treatments produced the highest concentrations of Cu and Pb. The concentrations of Cu, Cr, and Hg were strongly correlated with DOC (r(2) = 0.90, 0.91 and 0.96, respectively). A multi-surface geochemical model (SHM-DLM) produced values for metal dissolution that were usually of the correct magnitude. For Pb, however, the model was not successful indicating that the retention of this metal was stronger than assumed in the model. For all metals, the SHM-DLM model predicted that soil organic matter was the most important sorbent, although for Pb and Cr(III) ferrihydrite was also important and accounted for between 15 and 50% of the binding. The results confirm the central role of DOC for the mobilization of Cu, Cr, Hg and Pb in contaminated soils.
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| 675. |
- Lindfors, Axel, 1993-, et al.
(författare)
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Developing biogas systems in Norrköping, Sweden : An industrial symbiosis intervention
- 2020
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Ingår i: Journal of Cleaner Production. - : Elsevier. - 0959-6526 .- 1879-1786. ; 277
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Tidskriftsartikel (refereegranskat)abstract
- Biogas systems are often multi-functional and involve several actors in different sectors, requiring these actors to collaborate closely in order to implement such systems. In this paper, a study is presented where the theory of institutional capacity building is used to guide interventions with public and private actors to facilitate the development of local biogas systems in Norrköping, Sweden. The interventions were performed in the form of a workshop series, where local actors with potential to influence biogas developments actively took part. The workshop series generated knowledge on Norrköping’s significant potential for both producing and using biogas, which was traced, in part, to its high concentration of bio-based industries and its good position as a hub for transports. The interventions also created a shared understanding that cooperation and coordination to distribute resources and knowledge about biogas, both geographically and across sectors, was critical for realizing this potential. The municipal organization was identified as an important actor for coordinating these efforts. Observations during the workshops and survey responses indicate that the interventions contributed to building institutional capacity and initiation of efforts to develop local biogas solutions. Ideas put forth in this study enable interventions to target the intangible internal capacities of emerging industrial symbiosis networks. In addition, institutional capacity building serves as a useful analytical framework capable of capturing progress within emerging networks in the short-term even when material, water or energy synergies are yet to be realized.Biogas systems are often multi-functional and involve several actors in different sectors, requiring these actors to collaborate closely in order to implement such systems. In this paper, a study is presented where the theory of institutional capacity building is used to guide interventions with public and private actors to facilitate the development of local biogas systems in Norrköping, Sweden. The interventions were performed in the form of a workshop series, where local actors with potential to influence biogas developments actively took part. The workshop series generated knowledge on Norrköping’s significant potential for both producing and using biogas, which was traced, in part, to its high concentration of bio-based industries and its good position as a hub for transports. The interventions also created a shared understanding that cooperation and coordination to distribute resources and knowledge about biogas, both geographically and across sectors, was critical for realizing this potential. The municipal organization was identified as an important actor for coordinating these efforts. Observations during the workshops and survey responses indicate that the interventions contributed to building institutional capacity and initiation of efforts to develop local biogas solutions. Ideas put forth in this study enable interventions to target the intangible internal capacities of emerging industrial symbiosis networks. In addition, institutional capacity building serves as a useful analytical framework capable of capturing progress within emerging networks in the short-term even when material, water or energy synergies are yet to be realized.
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| 676. |
- Lindgren, David, et al.
(författare)
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A luminescence study of doping effects in InP-based radial nanowire structures
- 2013
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Ingår i: Journal of Physics, Conference Series. - : Institute of Physics Publishing (IOPP). - 1742-6588 .- 1742-6596. ; 471:1
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Tidskriftsartikel (refereegranskat)abstract
- We have used micro-photo- and cathodo-luminescence at low temperatures to study the effects of sulphur doping in InP and radial InP/InAs/InP structured nanowires. Samples with pure wurtzite crystal structure, with modulated wurtzite/zincblende crystal structure and with different radial InAs growth times were investigated. We observed a doping concentration gradient along the nanowires, the location of segments of different crystal structure and thickness fluctuations on the monolayer scale of the InAs layer.
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| 677. |
- Lindgren, David, et al.
(författare)
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Optical characterization of InAs quantum wells and dots grown radially on wurtzite InP nanowires.
- 2013
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Ingår i: Nanotechnology. - : IOP Publishing. - 0957-4484 .- 1361-6528. ; 24:22
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Tidskriftsartikel (refereegranskat)abstract
- Correlated micro-photoluminescence (μPL) and cathodoluminescence (CL) measurements are reported for single core-shell InP-InAs wurtzite nanowires grown using metal-organic vapor phase epitaxy. Samples covering a radial InAs shell thickness of 1-12 ML were investigated. The effective masses for the wurtzite material were determined from the transition energy dependence of the InAs shell thickness, using a model based on linear deformation potential theory. InP cores with segments of mixed zincblende and wurtzite, on which quantum dots nucleated selectively, were also investigated. Narrow peaks were observed by μPL and the spatial origin of the emission was identified with CL imaging.
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| 678. |
- Lindgren, Johan, et al.
(författare)
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Soft-tissue evidence for homeothermy and crypsis in a Jurassic ichthyosaur
- 2018
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Ingår i: Nature. - : Springer Science and Business Media LLC. - 0028-0836 .- 1476-4687. ; 564:7736
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Tidskriftsartikel (refereegranskat)abstract
- Ichthyosaurs are extinct marine reptiles that display a notable external similarity to modern toothed whales. Here we show that this resemblance is more than skin deep. We apply a multidisciplinary experimental approach to characterize the cellular and molecular composition of integumental tissues in an exceptionally preserved specimen of the Early Jurassic ichthyosaur Stenopterygius. Our analyses recovered still-flexible remnants of the original scaleless skin, which comprises morphologically distinct epidermal and dermal layers. These are underlain by insulating blubber that would have augmented streamlining, buoyancy and homeothermy. Additionally, we identify endogenous proteinaceous and lipid constituents, together with keratinocytes and branched melanophores that contain eumelanin pigment. Distributional variation of melanophores across the body suggests countershading, possibly enhanced by physiological adjustments of colour to enable photoprotection, concealment and/or thermoregulation. Convergence of ichthyosaurs with extant marine amniotes thus extends to the ultrastructural and molecular levels, reflecting the omnipresent constraints of their shared adaptation to pelagic life.
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| 679. |
- Lindhagen, Elin, et al.
(författare)
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In vitro activity of 20 agents in different prognostic subgroups of chronic lymphocytic leukaemia : rolipram and prednisolone active in cells from patients with poor prognosis
- 2009
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Ingår i: European Journal of Haematology. - : Wiley. - 0902-4441 .- 1600-0609. ; 83:1, s. 22-34
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Tidskriftsartikel (refereegranskat)abstract
- Background: There is a need for development of new drugs for treatment of B-cell chronic lymphocytic leukemia (CLL), especially for poor-prognostic subgroups resistant to conventional therapy. Objective: The in vitro antileukaemic activity of 20 different anticancer agents was characterized in tumour cells from CLL, aiming at identifying agents active in poor-prognostic subgroups.Design and methods: In tumour cells from 40 CLL patients and in peripheral blood mononuclear cells (PBMC) from 3 healthy controls, the activity of 20 substances was assessed using a non-clonogenic assay. The CLL samples were characterized regarding genomic aberrations by interphase FISH and immunoglobulin heavy-chain variable (IGHV) gene mutational status.Results:In line with clinical experience, cells from patients with unfavourable genomic aberrations (del(11q)/del(17p)) showed lower drug sensitivity to fludarabine and chlorambucil than cells from patients with favourable cytogenetics (del(13q)/no aberration). Most investigated drugs demonstrated similar activity in CLL cells from patients with unmutated and mutated IGHV genes as well as in CLL cells versus PBMC. Interestingly, prednisolone and rolipram displayed high CLL specificity, high activity in CLL cells with unmutated IGHV genes and retained the effect in several cases with 11q/17p deletion. Further studies on prednisolone and rolipram revealed a synergy when these agents were combined in CLL cells, and suggested correlation between drug sensitivity and difference in downstream signalling.Conclusion:Prednisolone and rolipram are interesting for further studies in CLL with inferior prognosis. The study can also be considered a basis for future efforts to find drugs active in subsets of CLL patients that are resistant to conventional therapy.
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| 680. |
- Lindqvist, Camilla, et al.
(författare)
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Fullerene mixtures enhance the thermal stability of a non-crystalline polymer solar cell blend
- 2014
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Ingår i: Applied Physics Letters. - : American Institute of Physics (AIP). - 0003-6951 .- 1077-3118. ; 104:15, s. 153301-
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Tidskriftsartikel (refereegranskat)abstract
- Printing of polymer: fullerene solar cells at high speed requires annealing at temperatures up to 140 degrees C. However, bulk-heterojunction blends that comprise a non-crystalline donor polymer often suffer from insufficient thermal stability and hence rapidly coarsen upon annealing above the glass transition temperature of the blend. In addition, micrometer-sized fullerene crystals grow, which are detrimental for the solar cell performance. In this manuscript, we present a strategy to limit fullerene crystallization, which is based on the use of fullerene mixtures of the two most common derivatives, PC61BM and PC71BM, as the acceptor material. Blends of this fullerene mixture and a non-crystalline thiophene-quinoxaline copolymer display considerably enhanced thermal stability and largely retain their photovoltaic performance upon annealing at elevated temperatures as high as 170 degrees C.
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