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  • 1.
    Almhöjd, Ulrika S.
    et al.
    Sahlgrenska Academy, Sweden.
    Lingström, Peter
    Sahlgrenska Academy, Sweden.
    Nilsson, Åke
    Sahlgrenska Academy, Sweden.
    Noren, Jörgen G.
    Sahlgrenska Academy, Sweden.
    Siljeström, Silje
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    ֖stlund, Å.
    RISE - Research Institutes of Sweden, Bioekonomi, Bioraffinaderi och energi.
    Bernin, D.
    University of Gothenburg, Sweden.
    Molecular Insights into Covalently Stained Carious Dentine Using Solid-State NMR and ToF-SIMS2017Inngår i: Caries Research, ISSN 0008-6568, E-ISSN 1421-976X, Vol. 51, nr 3, s. 255-263Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dyes currently used to stain carious dentine have a limited capacity to discriminate normal dentine from carious dentine, which may result in overexcavation. Consequently, finding a selective dye is still a challenge. However, there is evidence that hydrazine-based dyes, via covalent bonds to functional groups, bind specifically to carious dentine. The aim of this study was to investigate the possible formation of covalent bonds between carious dentine and 15N2-hydrazine and the hydrazine-based dye, 15N2-labelled Lucifer Yellow, respectively. Powdered dentine from extracted carious and normal teeth was exposed to the dyes, and the staining reactions were analysed using time-of-flight secondary ion mass spectrometry (ToF-SIMS), solid-state 13C-labelled nuclear magnetic resonance (NMR) and 15N-NMR spectroscopy. The results showed that 15N2-hydrazine and 15N2-labelled Lucifer Yellow both bind to carious dentine but not to normal dentine. It can thus be concluded that hydrazine-based dyes can be used to stain carious dentine and leave normal dentine unstained.

  • 2.
    An, Jungxue
    et al.
    KTH Royal Institute of Technology, Sweden.
    Jin, Chunsheng
    Sahlgrenska Academy, Sweden; University of Gothenburg, Sweden.
    Dėdinaitė, Andra
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Holgersson, Jan
    Sahlgrenska Academy, Sweden; University of Gothenburg, Sweden.
    Karlsson, Niclas G.
    Sahlgrenska Academy, Sweden; University of Gothenburg, Sweden.
    Claesson, Per M.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Influence of Glycosylation on Interfacial Properties of Recombinant Mucins: Adsorption, Surface Forces, and Friction2017Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 33, nr 18, s. 4386-4395Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Interfacial properties of two brush-with-anchor mucins, C-P55 and C-PSLex, have been investigated at the aqueous solution/poly(methyl methacrylate) (PMMA) interface. Both are recombinant mucin-type fusion proteins, produced by fusing the glycosylated mucin part of P-selectin glycoprotein ligand-1 (PSLG-1) to the Fc part of a mouse immunoglobulin in two different cells. They are mainly expressed as dimers upon production. Analysis of the O-glycans shows that the C-PSLex mucin has the longer and more branched side chains, but C-P55 has slightly higher sialic acid content. The adsorption of the mucins to PMMA surfaces was studied by quartz crystal microbalance with dissipation. The sensed mass, including the adsorbed mucin and water trapped in the layer, was found to be similar for these two mucin layers. Atomic force microscopy with colloidal probe was employed to study surface and friction forces between mucin-coated PMMA surfaces. Purely repulsive forces of steric origin were observed between mucin layers on compression, whereas a small adhesion was detected between both mucin layers on decompression. This was attributed to chain entanglement. The friction force between C-PSLex-coated PMMA is lower than that between C-P55-coated PMMA at low loads, but vice versa at high loads. We discuss our results in terms of the differences in the glycosylation composition of these two mucins.

  • 3.
    An, Junxue
    et al.
    KTH Royal Institute of Technology, Sweden.
    Liu, Xiaoyan
    KTH Royal Institute of Technology, Sweden.
    Dedinaite, Andra
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Korchagina, Evgeniya
    University of Montreal, Canada.
    Winnik, Francoise M.
    University of Montreal, Canada; National Institute for Materials Science, Japan; University of Helsinki, Finland.
    Claesson, Per M.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Dedinaite, Andra
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Effect of solvent quality and chain density on normal and frictional forces between electrostatically anchored thermoresponsive diblock copolymer layers2017Inngår i: Journal of Colloid and Interface Science, ISSN 0021-9797, E-ISSN 1095-7103, Vol. 487, s. 88-96Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Equilibration in adsorbing polymer systems can be very slow, leading to different physical properties at a given condition depending on the pathway that was used to reach this state. Here we explore this phenomenon using a diblock copolymer consisting of a cationic anchor block and a thermoresponsive block of poly(2-isopropyl-2-oxazoline), PIPOZ. We find that at a given temperature different polymer chain densities at the silica surface are achieved depending on the previous temperature history. We explore how this affects surface and friction forces between such layers using the atomic force microscope colloidal probe technique. The surface forces are purely repulsive at temperatures <40 °C. A local force minimum at short separation develops at 40 °C and a strong attraction due to capillary condensation of a polymer-rich phase is observed close to the bulk phase separation temperature. The friction forces decrease in the cooling stage due to rehydration of the PIPOZ chain. A consequence of the adsorption hysteresis is that the friction forces measured at 25 °C are significantly lower after exposure to a temperature of 40 °C than prior to heating, which is due to higher polymer chain density on the surface after heating.

  • 4.
    Andren, Oliver C. J.
    et al.
    KTH Royal Institute of Technology, Sweden.
    Ingverud, Tobias
    KTH Royal Institute of Technology, Sweden.
    Hult, Daniel
    KTH Royal Institute of Technology, Sweden.
    Håkansson, Joakim
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Bogestål, Yalda
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Caous, Josefin S
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Blom, Kristina
    Medibiome AB, Sweden.
    Zhang, Yuning
    KTH Royal Institute of Technology, Sweden.
    Andersson, Therese
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Pedersen, Emma
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Björn, Camilla
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Löwenhielm, Peter
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Malkoch, Michael
    KTH Royal Institute of Technology, Sweden.
    Antibiotic-Free Cationic Dendritic Hydrogels as Surgical-Site-Infection-Inhibiting Coatings2019Inngår i: Advanced Healthcare Materials, ISSN 2192-2640, E-ISSN 2192-2659, artikkel-id e1801619Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A non-toxic hydrolytically fast-degradable antibacterial hydrogel is herein presented to preemptively treat surgical site infections during the first crucial 24 h period without relying on conventional antibiotics. The approach capitalizes on a two-component system that form antibacterial hydrogels within 1 min and consist of i) an amine functional linear-dendritic hybrid based on linear poly(ethylene glycol) and dendritic 2,2-bis(hydroxymethyl)propionic acid, and ii) a di-N-hydroxysuccinimide functional poly(ethylene glycol) cross-linker. Broad spectrum antibacterial effect is achieved by multivalent representation of catatonically charged β-alanine on the dendritic periphery of the linear dendritic component. The hydrogels can be applied readily in an in vivo setting using a two-component syringe delivery system and the mechanical properties can accurately be tuned in the range equivalent to fat tissue and cartilage (G' = 0.5-8 kPa). The antibacterial effect is demonstrated both in vitro toward a range of relevant bacterial strains and in an in vivo mouse model of surgical site infection.

    Fulltekst (pdf)
    fulltext
  • 5.
    Antonsson, Ulf
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Byggteknik.
    Nordling, Bengt
    RISE - Research Institutes of Sweden (2017-2019), Samhällsbyggnad, Energi och cirkulär ekonomi.
    Demker, Ingvar
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Sjöqvist, Mia
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Funktionsprovning av tätskiktsystem förvåtutrymmen 20192018Rapport (Fagfellevurdert)
    Abstract [en]

    Functional testing of waterproofing systems for use behind ceramic tiling based on flexible sheets 2019

    Functional testing

    The result is worse than before.

    Six (32%) of the nineteen tested waterproofing systems passed the function test without leakage. Thirteen (68%) tests resulted in leakage.

    This result is worse than that obtained in the previous project in 2016, (1) when eight (40%) of twenty tested waterproofing systems passed the functional test without leakage. There has therefore been some deterioration in the as constructed systems.

    The result, however, is better than in the project performed in 2014 (2) when only three (15%) of twenty tested waterproofing systems passed without leakage.

    In this project, several leakages are localised around the penetrations of large and small drainpipes. This is an increase compared to previous studies. We have seen on several occasions that pipe collars have had poor quality. This has been noticed by that the polymer material used for sealing around the tube has lost its water tightness ability during the test. It is most probable that the material has a residual deformation (from setting) that causes the material to lose its ability to seal around the tube. We have also noted that the pipe collars have delaminated i.e. the layers in the collars have been divided into their individual constituents during the test.

    Leakages have also been caused by connections to gullies, inside corners, outside corners and in joints of foils.

    Fortunately, none of the investigative systems showed leakage that was so extensive that one could describe it as total damage.

    Water vapour resistance and mass per unit area

    Thirteen tested waterproofing on flexible sheet systems show a result between 2,5 and 4,5 million s/m, which is a high or very-high water vapour resistance. Six flexible sheet systems have a result below 2,5 million s/m.

    In the determination of water vapour resistance and mass per unit area, we can clearly see that some manufacturers have made changes in or replaced their flexible sheet with a new one, compared with the previous investigation (1).

    We further note that 10 out of 14 flexible sheets have a lower water vapor resistance than in the previous investigation (1). It is also notable that the PVC sealing layer has a low water vapor resistance.

    Indication of long-term properties

    In order to obtain an indication of the amount added antioxidants that improves the long-term properties of the materials, the DSC analysis of flexible sheets have been performed. In the same way as in the previous project, 2016, (1) it seems that the flexible sheets to be more stabilized for long-term use compared to the previous study in 2014, (2). However, for all analysed materials, to make a reliable service life prediction of the material, an accelerated ageing at moderate temperature is recommended.

    Fulltekst (pdf)
    fulltext
  • 6.
    Anyangwe Nwaboh, Javis
    et al.
    Physikalisch-Technische Bundesanstalt, Germany.
    Persijn, Stefan
    VSL Dutch Metrology Institute, The Netherlands.
    Arrhenius, Karine
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Bohlen, Haleh
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Werhahn, Olav
    Physikalisch-Technische Bundesanstalt, Germany.
    Ebert, Volker
    Physikalisch-Technische Bundesanstalt, Germany.
    Metrological quantification of CO in biogas using laser absorption spectroscopy and gas chromatography2018Inngår i: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 29, nr 9, artikkel-id 095010Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biogas has a vital role in the future market of renewable energy. When upgraded to biomethane, it can be injected into natural gas grids if the level of certain impurities complies with the specifications in EN16723. For some of these impurities, suitable measurement methods are lacking which hampers the quality control of biomethane to be injected into natural gas networks. Here, we report the evaluation of three detection methods suitable for carbon monoxide (CO) in biogas and biomethane applications for which EN16723 specifies an upper limit of 0.1% (1000 µmol/mol). Two of these methods are based on laser absorption spectroscopy (LAS) and one on gas chromatography (GC). Both LAS spectrometers are employing direct absorption spectroscopy and operating at 4.6µm, probing a single CO absorption line in the fundamental CO band: One – called dTDLAS (direct tunable diode laser absorption spectroscopy)- is based on a new Interband Cascade Laser specially designed for biogas and biomethane applications, while the other is based on Quantum Cascade Laser Absorption Spectroscopy (QCLAS). The GC is equipped with two packed columns (Hayesep Q and Molecular Sieve 5A) and a thermal conductivity detector. Carbon monoxide amount fraction results in biogas matrices derived using these three measurement methods are compared to amount fraction values of different, gravimetrically prepared reference gas standards of CO in biogas. These were used to validate the measurement capabilities. The measured CO amount fraction results from LAS and GC covered 10 µmol/mol to 30000 µmol/mol (system measurement ranges, LAS: 3 µmol/mol - 1000 µmol/mol, GC: 500 µmol/mol - 30000 µmol/mol) and were in excellent agreement with the gravimetric values of the gas standards. At 400 µmol/mol, the guide to the expression of uncertainty in measurement (GUM) compliant relative standard uncertainties of our calibration-free dTDLAS and the gas-calibrated QCLAS systems are estimated to be 1.4 % vs 0.5 %, respectively. The relative standard uncertainty of the GC CO measurements at 5075 µmol/mol is 1.3 %. This work demonstrates that, by means of GC and LAS, relative standard uncertainties of 1.4 % and below can be reached for CO measurements in biogas and that cost-optimized calibration-free approaches not requiring frequent use of gas standards have become available.

  • 7.
    Arrhenius, Karine
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Fischer, Andreas
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Büker, Oliver
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Mätteknik.
    Methods for sampling biogas and biomethane on adsorbent tubes after collection in gas bags2019Inngår i: Applied Sciences, E-ISSN 2076-3417, Vol. 9, nr 6, artikkel-id 1171Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biogas is a renewable energy source with many different production pathways and numerous excellent opportunities for use; for example, as vehicle fuel after upgrading (biomethane). Reliable analytical methodologies for assessing the quality of the gas are critical for ensuring that the gas can be used technically and safely. An essential part of any procedure aimed at determining the quality is the sampling and transfer to the laboratory. Sampling bags and sorbent tubes are widely used for collecting biogas. In this study, we have combined these two methods, i.e., sampling in a gas bag before subsequent sampling onto tubes in order to demonstrate that this alternative can help eliminate the disadvantages associated with the two methods whilst combining their advantages; with expected longer storage stability as well as easier sampling and transport. The results of the study show that two parameters need to be taken into account when transferring gas from a bag on to an adsorbent; the water content of the gas and the flow rate used during transfer of the gas on to the adsorbent. © 2019 by the authors.

  • 8.
    Arrhenius, Karine
    et al.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Karlsson, Anders
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Hakonen, Aron
    Ohlson, Lars
    Fordonsgas Sverige AB, Sweden.
    Yaghooby, Haleh
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Büker, Oliver
    RISE - Research Institutes of Sweden, Säkerhet och transport, Mätteknik.
    Variations of fuel composition during storage at Liquefied Natural Gas refuelling stations2018Inngår i: Journal of Natural Gas Science and Engineering, ISSN 1875-5100, E-ISSN 2212-3865, Vol. 49, s. 317-323Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Liquefied Natural Gas (LNG) and Liquefied Biogas (LBG) utilization within the heavy duty transport sector is today a sustainable alternative to the use of oil. However, in spite of the high degree of insulation in the storage tank walls, it is impossible to fully avoid any net heat input from the surroundings. Due to some degree of vaporization this results in variation in gas composition during storage at refuelling stations, potentially leading to engine failures. Within this study, a vaporizer/sampler has been built and tested at a station delivering liquefied biomethane (LBG) and occasionally; such in this case, LNG to heavy and medium duty trucks. The vaporizer/sampler has then been used to study the variation of the LNG composition in the storage tank during a two weeks period. The results clearly underline a correlation between the gas phase and the liquid phase as the concentration changes follow the same trend in both phases. Two opposite effects are assumed to influence the concentration of methane, ethane and propane in the liquid and in the gas phase. On one hand, because of the probable presence of not fully mixed layers in the storage tank and due to vehicles being refuelled, both liquid and gas phases are enriched in methane at the expense of ethane and propane. On the other hand, due to boil-off effect towards the end of the storage period, both liquid and gas phases are enriched in ethane and propane at the expense of methane.

  • 9.
    Arrhenius, Karine
    et al.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Yaghooby, Haleh
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Rosell, Lars
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Büker, Oliver
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Culleton, Lucy
    NPL National Physical Laboratory, UK.
    Bartlett, Sam
    NPL National Physical Laboratory, UK.
    Murugan, Arul
    NPL National Physical Laboratory, UK.
    Brewer, Paul
    NPL National Physical Laboratory, UK.
    Li, Jianrong
    VSL Van Swinden Laboratorium B.V., The Netherlands.
    van der Veen, Adriaan M. H.
    VSL Van Swinden Laboratorium B.V., The Netherlands.
    Krom, Iris
    VSL Van Swinden Laboratorium B.V., The Netherlands.
    Lestremau, Francoise
    INERIS Institut national de l'environnement industriel et des risques, France.
    Beranek, Jan
    ČMI Česky metrologicky institut, Czech Republic.
    Suitability of vessels and adsorbents for the short-term storage of biogas/biomethane for the determination of impurities – Siloxanes, sulfur compounds, halogenated hydrocarbons, BTEX2017Inngår i: Biomass and Bioenergy, ISSN 0961-9534, E-ISSN 1873-2909, Vol. 105, s. 127-135Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Biogas is a renewable energy source with many different production pathways and various excellent opportunities to use, for example as vehicle fuel (biomethane). Reliable analytical methodologies for assessing the quality of the gas are critical to ensure that the gas can technically and safely be used. An essential part of any procedure aiming to determine the quality is the sampling and the transfer to the laboratory. One of the greatest challenges is then to ensure that the composition of the sample collected does not change between the time of sampling and the analysis. The choice of the sampling vessel to be used must be made only after fully assessing its short-term stability. In this paper, the results from short-term stability studies in different vessels (cylinders, bags and sorbents) are presented for siloxanes, BTEX, halogenated hydrocarbons and sulfur compounds. Storage of dry gas at high pressure (> 6 MPa) appears to be a good alternative however it is currently challenging to find an optimal treatment of the cylinders for all species to be assessed in biogas/biomethane. At lower pressure, adsorption effects on the inner surface of the cylinders have been observed. The use of bags and sorbent tubes also shows limitation. No existing sorbent tubes are sufficiently universal as to trap all possible impurities and high boiling compounds may adsorbed on the inner surface of the bags walls. Moreover, the presence of water when storing biogas most certainly impacts the storage stability of compounds in most vessels. Using at least two sampling methods for a given compound and comparing results will allow taking into account the eventual effects of water vapour, and adsorption on the inner surface of the vessels.

  • 10.
    Arvidsson, Martin
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Ringstad, Lovisa
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Skedung, Lisa
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Duvefelt, Kenneth
    KTH Royal Institute of Technology, Sweden.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Feeling fine - the effect of topography and friction on perceived roughness and slipperiness2017Inngår i: Biotribology, ISSN 2352-5738, Vol. 11, s. 92-101Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    (1) Background. To design materials with specific haptic qualities, it is important to understand both the contribution of physical attributes from the surfaces of the materials and the perceptions that are involved in the haptic interaction. (2) Methods. A series of 16 wrinkled surfaces consisting of two similar materials of different elastic modulus and 8 different wrinkle wavelengths were characterized in terms of surface roughness and tactile friction coefficient. Sixteen participants scaled the perceived Roughness and Slipperiness of the surfaces using free magnitude estimation. Friction experiments were performed both by participants and by a trained experimenter with higher control. (3) Results and discussion. The trends in friction properties were similar for the group of participants performing the friction measurements in an uncontrolled way and the experiments performed under well-defined conditions, showing that the latter type of measurements represent the general friction properties well. The results point to slipperiness as the key perception dimension for textures below 100. μm and roughness above 100. μm. Furthermore, it is apparent that roughness and slipperiness perception of these types of structures are not independent. The friction is related to contact area between finger and material. Somewhat surprising was that the material with the higher elastic modulus was perceived as more slippery. A concluding finding was that the flat (high friction) reference surfaces were scaled as rough, supporting the theory that perceived roughness itself is a multidimensional construct with both surface roughness and friction component.

    Fulltekst (pdf)
    fulltext
  • 11.
    Bacquart, Thomas
    et al.
    National Physical Laboratory, UK.
    Arrhenius, Karine
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Persijn, Stefan
    VSL, Netherlands.
    Rojo, Andres
    CEM Centro Español de Metrología, Spain.
    Auprêtre, Fabien
    AREVA H2Gen, France.
    Gozlan, Bruno
    Paris-Saclay Research Center, France.
    Moore, Niamh
    National Physical Laboratory, UK.
    Morris, Abigail
    National Physical Laboratory, UK.
    Fischer, Andreas
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Murugan, Arul
    National Physical Laboratory, UK.
    Bartlett, Sam
    National Physical Laboratory, UK.
    Doucet, Guillaume
    AREVA H2Gen, France.
    Laridant, Francoise
    AREVA H2Gen, France.
    Gernot, Eric
    AREVA H2Gen, France.
    Fernández, Teresa
    CEM Centro Español de Metrología, Spain.
    Gómez, Concepcion
    CEM Centro Español de Metrología, Spain.
    Carré, Martine
    Paris-Saclay Research Center, France.
    De Reals, Guy
    Paris-Saclay Research Center, France.
    Haloua, Frederique
    Laboratoire National de métrologie et d’Essais, France.
    Hydrogen fuel quality from two main production processes: Steam methane reforming and proton exchange membrane water electrolysis2019Inngår i: Journal of Power Sources, ISSN 0378-7753, E-ISSN 1873-2755, Vol. 444, artikkel-id 227170Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The absence of contaminants in the hydrogen delivered at the hydrogen refuelling station is critical to ensure the length life of FCEV. Hydrogen quality has to be ensured according to the two international standards ISO 14687–2:2012 and ISO/DIS 19880-8. Amount fraction of contaminants from the two hydrogen production processes steam methane reforming and PEM water electrolyser is not clearly documented. Twenty five different hydrogen samples were taken and analysed for all contaminants listed in ISO 14687-2. The first results of hydrogen quality from production processes: PEM water electrolysis with TSA and SMR with PSA are presented. The results on more than 16 different plants or occasions demonstrated that in all cases the 13 compounds listed in ISO 14687 were below the threshold of the international standards. Several contaminated hydrogen samples demonstrated the needs for validated and standardised sampling system and procedure. The results validated the probability of contaminants presence proposed in ISO/DIS 19880-8. It will support the implementation of ISO/DIS 19880-8 and the development of hydrogen quality control monitoring plan. It is recommended to extend the study to other production method (i.e. alkaline electrolysis), the HRS supply chain (i.e. compressor) to support the technology growth.

  • 12.
    Badal Tejedor, Maria
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Niklas, Nordgren
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Schuleit, Michael
    Novartis Pharma AG, Switzerland.
    Pazesh, Samaneh
    Uppsala University, Sweden.
    Alderborn, Göran
    Uppsala University, Sweden.
    Millqvist-Fureby, Anna
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Determination of interfacial amorphicity in functional powders2017Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 33, nr 4, s. 920-926Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The nature of the surfaces of particles of pharmaceutical ingredients, food powders, and polymers is a determining factor for their performance in for example tableting, powder handling, or mixing. Changes on the surface structure of the material will impact the flow properties, dissolution rate, and tabletability of the powder blend. For crystalline materials, surface amorphization is a phenomenon which is known to impact performance. Since it is important to measure and control the level of amorphicity, several characterization techniques are available to determine the bulk amorphous content of a processed material. The possibility of characterizing the degree of amorphicity at the surface, for example by studying the mechanical properties of the particles' surface at the nanoscale, is currently only offered by atomic force microscopy (AFM). The AFM PeakForce QNM technique has been used to measure the variation in energy dissipation (eV) at the surface of the particles which sheds light on the mechanical changes occurring as a result of amorphization or recrystallization events. Two novel approaches for the characterization of amorphicity are presented here. First, since particles are heterogeneous, we present a methodology to present the results of extensive QNM analysis of multiple particles in a coherent and easily interpreted manner, by studying cumulative distributions of dissipation data with respect to a threshold value which can be used to distinguish the crystalline and amorphous states. To exemplify the approach, which is generally applicable to any material, reference materials of purely crystalline α-lactose monohydrate and completely amorphous spray dried lactose particles were compared to a partially amorphized α-lactose monohydrate sample. Dissipation data are compared to evaluations of the lactose samples with conventional AFM and SEM showing significant topographical differences. Finally, the recrystallization of the surface amorphous regions in response to humidity was followed by studying the dissipation response of a well-defined surface region over time, which confirms both that dissipation measurement is a useful measure of surface amorphicity and that significant recrystallization occurs at the surface in response to humidity.

  • 13.
    Bannow, J.
    et al.
    KTH Royal Institute of Technology, Sweden.
    Benjamins, Jan-Willem
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Wohlert, J.
    KTH Royal Institute of Technology, Sweden.
    Löbmann, K.
    University of Copenhagen, Denmark.
    Svagan, A. J.
    KTH Royal Institute of Technology, Sweden.
    Solid nanofoams based on cellulose nanofibers and indomethacin—the effect of processing parameters and drug content on material structure2017Inngår i: International Journal of Pharmaceutics, ISSN 0378-5173, E-ISSN 1873-3476, Vol. 526, nr 1-2, s. 291-299Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The unique colloidal properties of cellulose nanofibers (CNF), makes CNF a very interesting new excipient in pharmaceutical formulations, as CNF in combination with some poorly-soluble drugs can create nanofoams with closed cells. Previous nanofoams, created with the model drug indomethacin, demonstrated a prolonged release compared to films, owing to the tortuous diffusion path that the drug needs to take around the intact air-bubbles. However, the nanofoam was only obtained at a relatively low drug content of 21 wt% using fixed processing parameters. Herein, the effect of indomethacin content and processing parameters on the foaming properties was analysed. Results demonstrate that a certain amount of dissolved drug is needed to stabilize air-bubbles. At the same time, larger fractions of dissolved drug promote coarsening/collapse of the wet foam. The pendant drop/bubble profile tensiometry was used to verify the wet-foam stability at different pHs. The pH influenced the amount of solubilized drug and the processing-window was very narrow at high drug loadings. The results were compared to real foaming-experiments and solid state analysis of the final cellular solids. The parameters were assembled into a processing chart, highlighting the importance of the right combination of processing parameters (pH and time-point of pH adjustment) in order to successfully prepare cellular solid materials with up to 46 wt% drug loading.

  • 14.
    Baresel, Christian
    et al.
    IVL Swedish Environmental Research Institute AB, Sweden.
    Schaller, Vincent
    RISE - Research Institutes of Sweden (2017-2019), ICT, Acreo.
    Jonasson, Christian
    RISE - Research Institutes of Sweden (2017-2019), ICT, Acreo.
    Johansson, Christer
    RISE - Research Institutes of Sweden (2017-2019), ICT, Acreo.
    Bordes, Romain
    Chalmers University of Technology, Sweden.
    Chauhan, Vinay
    Chalmers University of Technology, Sweden.
    Sugunan, Abhilash
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Sommertune, Jens
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Welling, Sebastian
    IVL Swedish Environmental Research Institute AB, Sweden.
    Functionalized magnetic particles for water treatment2019Inngår i: Heliyon, E-ISSN 2405-8440, Vol. 5, nr 8, artikkel-id e02325Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, we have taken the concept of water treatment by functionalized magnetic particles one step forward by integrating the technology into a complete proof of concept, which included the preparation of surface modified beads, their use as highly selective absorbents for heavy metals ions (Zinc, Nickel), and their performance in terms of magnetic separation. The separation characteristics were studied both through experiments and by simulations. The data gathered from these experimental works enabled the elaboration of various scenarios for Life Cycle Analysis (LCA). The LCA showed that the environmental impact of the system is highly dependent on the recovery rate of the magnetic particles. The absolute impact on climate change varied significantly among the scenarios studied and the recovery rates. The results support the hypothesis that chelation specificity, magnetic separation and bead recovery should be optimized to specific targets and applications. 

  • 15.
    Barwick, Vicki
    et al.
    LGC Ltd, UK.
    Ellison, Stephen L. R.
    LGC Ltd, UK.
    Gjengedal, Elin
    NTNU Norwegian University of Life Sciences, Norway.
    Magnusson, Bertil
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Molinier, Olivier
    Aglae, France.
    Patriarca, Marina
    Istituto Superiore di Sanità, Italy.
    Sibbesen, Lorens
    LAB Quality International, Denmark.
    Vanlaethem, Nicole
    Classes Moyennes et Energie, Belgium.
    Vercruysse, Isabelle
    Belab, Belgium.
    Method validation in analytical sciences: discussions on current practice and future challenges2017Inngår i: Accreditation and Quality Assurance, ISSN 0949-1775, E-ISSN 1432-0517, Vol. 22, nr 5, s. 253-263Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Eurachem held a workshop on method validation in analytical sciences in Gent, Belgium, on 9–10 May 2016. A summary of the working group discussions is provided here. The discussions covered a range of issues concerned with current practice and future challenges in method validation, i.e. setting requirements for a method to be validated; planning validation studies; validation of qualitative and semi-quantitative methods; validation of multi-parameter methods; determination of trueness/bias; assessment of working range; validation in microbiology; and method validation under flexible scope of accreditation. Delegates (129) from 24 different countries and from different backgrounds, e.g. from both public and private laboratories, laboratory associations, accreditation bodies and universities, attended the working groups, thus providing opportunities to collect a variety of views and experiences as well as to identify potential gaps in current guidance and regulations. While the practicalities of assessing method performance characteristics are generally well understood, the issue of setting requirements for those characteristics beforehand is less straightforward. Although a number of documents addressing the principles of method validation are available, guidance on dealing with more complex and ‘non-ideal’ situations, as well as examples of good practice, would be welcomed and greater harmonisation of approaches was deemed necessary. There remains a need for guidance on both the concepts that apply to ‘qualitative’ or ‘nominal’ test methods and on the practical implementation of validation studies in such cases.

  • 16.
    Beaty, D. W.
    et al.
    California Institute of Technology, US.
    Grady, M. M.
    Open University, UK.
    McSween, H. Y.
    University of Tennessee, US.
    Carrier, B. L.
    California Institute of Technology, US.
    Amelin, Y.
    Australian National University, Australia.
    Anand, M.
    Open University, UK.
    Bishop, J. L.
    SETI Institute, US.
    Boucher, D.
    Deltion Innovations, Canada.
    Busemann, H.
    Campbell, K. A.
    Czaja, A. D.
    Debaille, V.
    Des Marais, D. J.
    Dixon, M.
    Ehlmann, B. L.
    Farmer, J. D.
    Fernandez-Remolar, D. C.
    Filiberto, J.
    Fogarty, J.
    Glavin, D. P.
    Goreva, Y. S.
    Hallis, L. J.
    Harrington, A. D.
    M. Hausrath, E.
    Herd, C. D. K.
    Horgan, B.
    Humanyun, M.
    Kleine, T.
    Kleinhenz, J.
    Mackelprang, R.
    Mangold, N.
    Mayhew, L. E.
    McCoy, J. T.
    McCubbin, F. M.
    McLennan, S. M.
    Moser, D. E.
    Moynier, F.
    Mustard, J. F.
    Niles, P. B.
    Ori, G. G.
    Raulin, F.
    Rettberg, P.
    Rucker, M. A.
    Schmitz, N.
    Schwenzer, S. P.
    Sephton, M. A.
    Shaheen, R.
    Sharp, Z. D.
    Schuster, D. L.
    Siljeström, Sandra
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Smith, C. L.
    Spry, J. A.
    Steele, A.
    Swindle, T. D.
    ten Kate, I. L.
    Tosca, N. J.
    Usui, T.
    Van Kranendonk, M. J.
    Wadhwa, M.
    Weiss, B. P.
    Werner, S. C.
    Westall, F.
    Wheeler, R. M.
    Zipfel, J.
    Zorzano, M. P.
    The potential science and engineering value of samples delivered to Earth by Mars sample return2019Inngår i: Meteoritics and Planetary Science, ISSN 1086-9379, E-ISSN 1945-5100, Vol. 54, nr 3, s. 667-671Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Executive summary provided in lieu of abstract. © 2019 The Authors.

  • 17.
    Bender, P.
    et al.
    University of Cantabria, Spain .
    Bogart, L. K.
    University College London, UK .
    Posth, O.
    Physikalisch-Technische Bundesanstalt, Germany .
    Szczerba, W.
    BAM Bundesanstalt für Materialforschung Und-prüfung, Germany ; AGH University of Science and Technology, Poland .
    Rogers, S. E.
    ISIS-STFC Neutron Scattering Facility, UK.
    Castro, A.
    SOLVE Research and Consultancy AB, Sweden .
    Nilsson, L.
    SOLVE Research and Consultancy AB, Sweden; Lund University, Sweden.
    Zeng, L. J.
    Chalmers University of Technology, Sweden.
    Sugunan, Abhilash
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Sommertune, Jens
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Fornara, A.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    González-Alonso, D.
    University of Cantabria, Spain .
    Fernández Barquín, L.
    University of Cantabria, Spain.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Structural and magnetic properties of multi-core nanoparticles analysed using a generalised numerical inversion method2017Inngår i: Scientific Reports, E-ISSN 2045-2322, Vol. 7, artikkel-id 45990Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The structural and magnetic properties of magnetic multi-core particles were determined by numerical inversion of small angle scattering and isothermal magnetisation data. The investigated particles consist of iron oxide nanoparticle cores (9 nm) embedded in poly(styrene) spheres (160 nm). A thorough physical characterisation of the particles included transmission electron microscopy, X-ray diffraction and asymmetrical flow field-flow fractionation. Their structure was ultimately disclosed by an indirect Fourier transform of static light scattering, small angle X-ray scattering and small angle neutron scattering data of the colloidal dispersion. The extracted pair distance distribution functions clearly indicated that the cores were mostly accumulated in the outer surface layers of the poly(styrene) spheres. To investigate the magnetic properties, the isothermal magnetisation curves of the multi-core particles (immobilised and dispersed in water) were analysed. The study stands out by applying the same numerical approach to extract the apparent moment distributions of the particles as for the indirect Fourier transform. It could be shown that the main peak of the apparent moment distributions correlated to the expected intrinsic moment distribution of the cores. Additional peaks were observed which signaled deviations of the isothermal magnetisation behavior from the non-interacting case, indicating weak dipolar interactions.

  • 18.
    Besharat, Zahra
    et al.
    KTH Royal Institute of Technology, Sweden.
    Yazdi, Milad Ghadami
    KTH Royal Institute of Technology, Sweden.
    Wakeham, Deborah
    KTH Royal Institute of Technology, Sweden.
    Johnson, Magnus
    KTH Royal Institute of Technology, Sweden.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Gothelid, Mats
    KTH Royal Institute of Technology, Sweden.
    Gronbeck, Henrik
    Chalmers University of Technology, Sweden.
    Se-C Cleavage of Hexane Selenol at Steps on Au(111)2018Inngår i: Langmuir, ISSN 0743-7463, E-ISSN 1520-5827, Vol. 34, nr 8, s. 2630-2636Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Selenols are considered as an alternative to thiols in self-assembled monolayers, but the Se-C bond is one limiting factor for their usefulness. In this study, we address the stability of the Se-C bond by a combined experimental and theoretical investigation of gas phase-deposited hexane selenol (CH3(CH2)(5)SeH) on Au(111) using photoelectron spectroscopy, scanning tunneling microscopy, and density functional theory (DFT). Experimentally, we find that initial adsorption leaves atomic Se on the surface without any carbon left on the surface, whereas further adsorption generates a saturated selenolate layer. The Se 3d component from atomic Se appears at 0.85 eV lower binding energy than the selenolate-related component. DFT calculations show that the most stable structure of selenols on Au(111) is in the form of RSe-Au-SeR complexes adsorbed on the unreconstructed Au(111) surface. This is similar to thiols on Au(111). Calculated Se 3d core-level shifts between elemental Se and selenolate in this structure nicely reproduce the experimentally recorded shifts. Dissociation of RSeH and subsequent formation of RH are found to proceed with high barriers on defect-free Au(111) terraces, with the highest barrier for scissoring R-Se. However, at steps, these barriers are considerably lower, allowing for Se-C bond breaking and hexane desorption, leaving elemental Se at the surface. Hexane is the selenol to selenolate formed by replacing the Se-C bond with a H-C bond by using the hydrogen liberated from transformation.

  • 19.
    Bhattacharya, Kunal
    et al.
    Karolinska Institutet, Sweden.
    Sacchetti, Cristiano
    La Jolla Institute for Allergy and Immunology, USA; University of California San Diego, USA.
    Costa, Pedro M.
    Karolinska Institutet, Sweden.
    Sommertune, Jens
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Brandner, Birgit D.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Magrini, Andrea
    University of Rome Tor Vergata, Italy.
    Rosato, Nicola
    University of Rome Tor Vergata, Italy.
    Bottini, Nunzio
    La Jolla Institute for Allergy and Immunology, USA; University of California San Diego, USA.
    Bottini, Massimo
    University of Rome Tor Vergata, Italy; Sanford Burnham Presbys Medical Discovery Institute, USA.
    Fadeel, Bengt
    Karolinska Institutet, Sweden.
    Nitric Oxide Dependent Degradation of Polyethylene Glycol-Modified Single-Walled Carbon Nanotubes: Implications for Intra-Articular Delivery2018Inngår i: Advanced Healthcare Materials, ISSN 2192-2640, E-ISSN 2192-2659, Vol. 7, nr 6, artikkel-id 1700916Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Polyethylene glycol (PEG)-modified carbon nanotubes have been successfully employed for intra-articular delivery in mice without systemic or local toxicity. However, the fate of the delivery system itself remains to be understood. In this study 2 kDa PEG-modified single-walled carbon nanotubes (PNTs) are synthesized, and trafficking and degradation following intra-articular injection into the knee-joint of healthy mice are studied. Using confocal Raman microspectroscopy, PNTs can be imaged in the knee-joint and are found to either egress from the synovial cavity or undergo biodegradation over a period of 3 weeks. Raman analysis discloses that PNTs are oxidatively degraded mainly in the chondrocyte-rich cartilage and meniscus regions while PNTs can also be detected in the synovial membrane regions, where macrophages can be found. Furthermore, using murine chondrocyte (ATDC-5) and macrophage (RAW264.7) cell lines, biodegradation of PNTs in activated, nitric oxide (NO)-producing chondrocytes, which is blocked upon pharmacological inhibition of inducible nitric oxide synthase (iNOS), can be shown. Biodegradation of PNTs in macrophages is also noted, but after a longer period of incubation. Finally, cell-free degradation of PNTs upon incubation with the peroxynitrite-generating compound, SIN-1 is demonstrated. The present study paves the way for the use of PNTs as delivery systems in the treatment of diseases of the joint.

  • 20.
    Boge, Lucas
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Umerska, Anita
    INSERM U 1066, France ; Université Angers, France.
    Matougui, Nada
    INSERM U 1066, France ; Université Angers,France.
    Bysell, Helena
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Ringstad, Lovisa
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Davoudi, Mina
    Lund University, Sweden.
    Eriksson, Jonny
    Uppsala University, Sweden.
    Edwards, Katarina
    Uppsala University, Sweden.
    Andersson, Martin
    Chalmers University of Technology, Sweden.
    Cubosomes post-loaded with antimicrobial peptides: Characterization, bactericidal effect and proteolytic stability2017Inngår i: International Journal of Pharmaceutics, ISSN 0378-5173, E-ISSN 1873-3476, Vol. 526, nr 1-2, s. 400-412Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Novel antibiotics, such as antimicrobial peptides (AMPs), have recently attended more and more attraction. In this work, dispersed cubic liquid crystalline gel (cubosomes) was used as drug delivery vehicles for three AMPs (AP114, DPK-060 and LL-37). Association of peptides onto cubosomes was studied at two cubosome/peptide ratios using high performance liquid chromatography, ζ-potential and circular dichroism measurements. AMPs impact on the cubosome structure was investigated using small angle x-ray scattering and cryogenic transmission electron microscopy. The antimicrobial effect of the AMP loaded cubosomes was studied in vitro by minimum inhibitory concentration and time-kill assays. Proteolytic protection was investigated by incubating the formulations with two elastases and the antimicrobial effect after proteolysis was studied using radial diffusion assay. Different association efficacy onto the cubosomes was observed among the AMPs, with LL-37 showing greatest association (>60%). AP114 loaded cubosomes displayed a preserved antimicrobial effect, whereas for LL-37 the broad spectrum bacterial killing was reduced to only comprise Gram-negative bacteria. Interestingly, DPK-060 loaded cubosomes showed a slight enhanced effect against S. aureus and E. coli strains. Moreover, the cubosomes were found to protect LL-37 from proteolytic degradation, resulting in a significantly better bactericidal effect after being subjected to elastase, compared to unformulated peptide.

    Fulltekst (pdf)
    fulltext
  • 21.
    Boge, Lukas
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Yta, process och formulering. Chalmers University of Technology, Sweden.
    Browning, Kathryn
    University of Copenhagen, Denmark.
    Nordström, Randi
    Uppsala University, Sweden.
    Campana, Mario
    Rutherford Appleton Laboratory, UK.
    Damgaard, Liv
    University of Copenhagen, Denmark.
    Seth Caous, Josefin
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Hellsing, Maja
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Yta, process och formulering.
    Ringstad, Lovisa
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Andersson, Martin
    Chalmers University of Technology, Sweden.
    Peptide-Loaded Cubosomes Functioning as an Antimicrobial Unit against Escherichia coli2019Inngår i: ACS Applied Materials and Interfaces, ISSN 1944-8244, E-ISSN 1944-8252, Vol. 11, nr 24, s. 21314-21322Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Dispersions of cubic liquid crystalline phases, also known as cubosomes, have shown great promise as delivery vehicles for a wide range of medicines. Due to their ordered structure, comprising alternating hydrophilic and hydrophobic domains, cubosomes possess unique delivery properties and compatibility with both water-soluble and -insoluble drugs. However, the drug delivery mechanism and cubosome interaction with human cells and bacteria are still poorly understood. Herein, we reveal how cubosomes loaded with the human cathelicidin antimicrobial peptide LL-37, a system with high bacteria-killing effect, interact with the bacterial membrane and provide new insights into the eradication mechanism. Combining the advanced experimental techniques neutron reflectivity and quartz crystal microbalance with dissipation monitoring, a mechanistic drug delivery model for LL-37-loaded cubosomes on bacterial mimicking bilayers was constructed. Moreover, the cubosome interaction with Escherichia coli was directly visualized using super-resolution laser scanning microscopy and cryogenic electron tomography. We could conclude that cubosomes loaded with LL-37 adsorbed and distorted bacterial membranes, providing evidence that the peptide-loaded cubosomes function as an antimicrobial unit.

  • 22.
    Boge, Lukas
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Yta, process och formulering. Chalmers University of Technology, Sweden.
    Hallstensson, Karin
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Yta, process och formulering.
    Ringstad, Lovisa
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Yta, process och formulering.
    Johansson, Jenny
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Andersson, Therese
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Davoudi, Mina
    Lund University, Sweden.
    Larsson, Per Tomas
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Mahlapuu, Margit
    Promore Pharma AB, Sweden; University of Gothenburg, Sweden.
    Håkansson, Joakim
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Andersson, Martin
    Chalmers University of Technology, Sweden.
    Cubosomes for topical delivery of the antimicrobial peptide LL-372019Inngår i: European journal of pharmaceutics and biopharmaceutics, ISSN 0939-6411, E-ISSN 1873-3441, Vol. 134, s. 60-67Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, the use of cubosomes for topical delivery of the antimicrobial peptide (AMP) LL-37 was investigated. Topical delivery of AMPs is of great interest for treatment of skin infections caused by bacteria, such as Staphylococcus aureus. AMP containing cubosomes were produced by three different preparation protocols and compared: (i) pre-loading, where LL-37 was incorporated into a liquid crystalline gel, which thereafter was dispersed into nanoparticles, (ii) post-loading, where LL-37 was let to adsorb onto pre-formed cubosomes, and (iii) hydrotrope-loading, where LL-37 was incorporated during the spontaneously formed cubosomes in an ethanol/glycerol monooleate mixture. Particle size and size distribution were analyzed using dynamic light scattering (DLS), liquid crystalline structure by small angle x-ray scattering (SAXS) and release of LL-37 by a fluorescamine assay. Proteolytic protection of LL-37 as well as bactericidal effect after enzyme exposure was investigated. The skin irritation potential of cubosomes was examined by an in vitro epidermis model. Finally, the bacterial killing property of the cubosomes was examined by an ex vivo pig skin wound infection model with Staphylococcus aureus. Data showed that a high loading of LL-37 induced formation of vesicles in case of cubosomes prepared by sonication (pre-loading). No release of LL-37 was observed from the cubosomes, indicating strong association of the peptide to the particles. Proteolysis studies showed that LL-37 was fully protected against enzymatic attacks while associated with the cubosomes, also denoting strong association of the peptide to the particles. As a consequence, bactericidal effect after enzyme exposure remained, compared to pure LL-37 which was subjected to proteolysis. No skin irritation potential of the cubosomes was found, thus enabling for topical administration. The ex vivo wound infection model showed that LL-37 in pre-loaded cubosomes killed bacteria most efficient.

  • 23.
    Brooke, Darby G.
    et al.
    Cawthron Institute, New Zealand.
    Cervin, Gunnar
    University of Gothenburg, Sweden.
    Champeau, Olivier
    Cawthron Institute, New Zealand.
    Harwood, David Tim
    Cawthron Institute, New Zealand.
    Pavia, Henrik
    University of Gothenburg, Sweden.
    Selwood, Andrew I.
    Cawthron Institute, New Zealand.
    Svenson, Johan
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Tremblay, Louis A.
    Cawthron Institute, New Zealand; University of Auckland, New Zealand.
    Cahill, Patrick Louis
    Cawthron Institute, New Zealand.
    Antifouling activity of portimine, select semisynthetic analogues, and other microalga-derived spirocyclic imines2018Inngår i: Biofouling (Print), ISSN 0892-7014, E-ISSN 1029-2454, Vol. 34, nr 8, s. 950-961Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A range of natural products from marine invertebrates, bacteria and fungi have been assessed as leads for nature-inspired antifouling (AF) biocides, but little attention has been paid to microalgal-derived compounds. This study assessed the AF activity of the spirocyclic imine portimine (1), which is produced by the benthic mat-forming dinoflagellate Vulcanodinium rugosum. Portimine displayed potent AF activity in a panel of four macrofouling bioassays (EC50 0.06–62.5 ng ml−1), and this activity was distinct from that of the related compounds gymnodimine-A (2), 13-desmethyl spirolide C (3), and pinnatoxin-F (4). The proposed mechanism of action for portimine is induction of apoptosis, based on the observation that portimine inhibited macrofouling organisms at developmental stages known to involve apoptotic processes. Semisynthetic modification of select portions of the portimine molecule was subsequently undertaken. Observed changes in bioactivity of the resulting semisynthetic analogues of portimine were consistent with portimine’s unprecedented 5-membered imine ring structure playing a central role in its AF activity.

  • 24.
    Chen, Chengdong
    et al.
    Xiamen University, China; KTH Royal Institute of Technology, Sweden.
    Hou, Ruiqing
    Xiamen University, China; Institute of Materials Research, Germany.
    Zhang, Fan
    KTH Royal Institute of Technology, Sweden.
    Dong, Shigang
    Xiamen University, China.
    Claesson, Per Martin
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. Xiamen University, China.
    Lin, Changjian
    KTH Royal Institute of Technology, Sweden.
    Pan, Jinshan
    KTH Royal Institute of Technology, Sweden.
    Heating-Induced Enhancement of Corrosion Protection of Carbon Steel by a Nanocomposite Film Containing Mussel Adhesive Protein2017Inngår i: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 164, nr 4, s. C188-C193Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Application of protective coatings on metals may involve a thermal treatment process. In this study, the effect of thermal treatment up to 200?C on the corrosion protection was investigated for nanocomposite films composed of mussel adhesive protein (MAP), CeO2 nanoparticles and Na2HPO4 deposited on carbon steel. The morphology and microstructure of the pre-formed nanocomposite film were characterized by scanning electron microscopy/energy dispersive spectroscopy and atomic force microscopy (AFM). The changes in the chemical structure of the nanocomposite film due to the thermal treatment were investigated by infrared reflection absorption spectroscopy. The corrosion protection of the unheated and heated nanocomposite films on carbon steel was evaluated by electrochemical impedance spectroscopy and details of the corrosion process were elucidated by in-situ AFM measurements in 0.1 M NaCl solution. The results show a certain increase in the corrosion protection with time of the nanocomposite film for carbon steel. The analyses reveal that thermal treatment leads to a reduction of water molecules in the nanocomposite film, and an enhanced cross-linking and cohesion of the film due to oxidation of catechols to o-quinones. As a result, the film becomes more compact and gives improved corrosion protection for carbon steel.

  • 25.
    Cheregi, O.
    et al.
    University of Gothenburg, Sweden.
    Ekendahl, Susanne
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Engelbrektsson, Johan
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Strömberg, Niklas
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Godhe, A.
    University of Gothenburg, Sweden.
    Spetea, C.
    University of Gothenburg, Sweden.
    Microalgae biotechnology in Nordic countries – the potential of local strains2019Inngår i: Physiologia Plantarum, ISSN 0031-9317, E-ISSN 1399-3054, Vol. 166, nr 1, s. 438-450Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Climate change, energy use and food security are the main challenges that our society is facing nowadays. Biofuels and feedstock from microalgae can be part of the solution if high and continuous production is to be ensured. This could be attained in year-round, low cost, outdoor cultivation systems using strains that are not only champion producers of desired compounds but also have robust growth in a dynamic climate. Using microalgae strains adapted to the local conditions may be advantageous particularly in Nordic countries. Here, we review the current status of laboratory and outdoor-scale cultivation in Nordic conditions of local strains for biofuel, high-value compounds and water remediation. Strains suitable for biotechnological purposes were identified from the large and diverse pool represented by saline (NE Atlantic Ocean), brackish (Baltic Sea) and fresh water (lakes and rivers) sources. Energy-efficient annual rotation for cultivation of strains well adapted to Nordic climate has the potential to provide high biomass yields for biotechnological purposes

  • 26.
    Chinga-Carrasco, Gary
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, PFI.
    Ehman, Nanci
    IMAM, Argentina.
    Filgueira, Daniel
    RISE - Research Institutes of Sweden, Bioekonomi, PFI.
    Johansson, Jenny
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Vallejos, Maria
    IMAM, Argentina.
    Felissia, Fernando
    IMAM, Argentina.
    Håkansson, Joakim
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Area, Maria
    IMAM, Argentina.
    Bagasse—A major agro-industrial residue as potential resource for nanocellulose inks for 3D printing of wound dressing devices2019Inngår i: Additive Manufacturing, ISSN 2214-8604, E-ISSN 2214-7810, Vol. 28, s. 267-274Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Sugarcane bagasse, an abundant residue, is usually burned as an energy source. However, provided that appropriate and sustainable pulping and fractionation processes are applied, bagasse can be utilized as a main source of cellulose nanofibrils (CNF). We explored in this study the production of CNF inks for 3D printing by direct-ink-writing technology. The CNF were tested against L929 fibroblasts cell line and we confirmed that the CNF from soda bagasse fibers were found not to have a cytotoxic potential. Additionally, we demonstrated that the alginate and Ca 2+ caused significant dimensional changes to the 3D printed constructs. The CNF-alginate grids exhibited a lateral expansion after printing and then shrank due to the cross-linking with the Ca 2+ . The release of Ca 2+ from the CNF and CNF-alginate constructs was quantified thus providing more insight about the CNF as carrier for Ca 2+ . This, combined with 3D printing, offers potential for personalized wound dressing devices, i.e. tailor-made constructs that can be adapted to a specific shape, depending on the characteristics of the wound healing treatment.

  • 27.
    Chinga-Carrasco, Gary
    et al.
    RISE - Research Institutes of Sweden, Bioekonomi, PFI.
    Ehman, Nanci V.
    IMAM Instituto de Materiales de Misiones, Argentina.
    Pettersson, Jennifer
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Vallejos, Maria E.
    IMAM Instituto de Materiales de Misiones, Argentina.
    Brodin, Malin
    RISE - Research Institutes of Sweden, Bioekonomi, PFI.
    Felissia, Fernando E.
    IMAM Instituto de Materiales de Misiones, Argentina.
    Håkansson, Joakim
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Area, Maria C.
    IMAM Instituto de Materiales de Misiones, Argentina.
    Pulping and Pretreatment Affect the Characteristics of Bagasse Inks for Three-dimensional Printing2018Inngår i: ACS Sustainable Chemistry and Engineering, E-ISSN 2168-0485, Vol. 6, nr 3, s. 4068-4075Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Bagasse is an underutilized agro-industrial residue with great potential as raw material for the production of cellulose nanofibrils (CNF) for a range of applications. In this study, we have assessed the suitability of bagasse for production of CNF for three-dimensional (3D) printing. First, pulp fibers were obtained from the bagasse raw material using two fractionation methods, i.e. soda and hydrothermal treatment combined with soda. Second, the pulp fibers were pretreated by TEMPO-mediated oxidation using two levels of oxidation for comparison purposes. Finally, the CNF were characterized in detail and assessed as inks for 3D printing. The results show that CNF produced from fibers obtained by hydrothermal and soda pulping were less nanofibrillated than the corresponding material produced by soda pulping. However, the CNF sample obtained from soda pulp was cytotoxic, apparently due to a larger content of silica particles. All the CNF materials were 3D printable. We conclude that the noncytotoxic CNF produced from hydrothermally and soda treated pulp can potentially be used as inks for 3D printing of biomedical devices. 

  • 28.
    Costa, Carolina
    et al.
    Mid Sweden University, Sweden.
    Mira, Isabel
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Yta, process och formulering.
    Benjamins, Jan-Willem
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Lindman, Björn
    Mid Sweden University, Sweden.
    Edlund, Håkan
    Mid Sweden University, Sweden.
    Norgren, Magnus
    Mid Sweden University, Sweden.
    Interfacial activity and emulsion stabilization of dissolved cellulose2019Inngår i: Journal of Molecular Liquids, ISSN 0167-7322, E-ISSN 1873-3166, Vol. 292, artikkel-id 111325Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Some aspects of the interfacial behavior of cellulose dissolved in an aqueous solvent were investigated. Cellulose was found to significantly decrease the interfacial tension (IFT) between paraffin oil and 85 wt% phosphoric acid aqueous solutions. This decrease was similar in magnitude to that displayed by non-ionic cellulose derivatives. Cellulose's interfacial activity indicated a significant amphiphilic character and that the interfacial activity of cellulose derivatives is not only related to the derivatization but inherent in the cellulose backbone. This finding suggests that cellulose would have the ability of stabilizing dispersions, like oil-in-water emulsions in a similar way as a large number of cellulose derivatives. In its molecularly dissolved state, cellulose proved to be able to stabilize emulsions of paraffin in the polar solvent on a short-term. However, long-term stability against drop-coalescence was possible to achieve by a slight change in the amphiphilicity of cellulose, effected by a slight increase in pH. These emulsions exhibited excellent stability against coalescence/oiling-off over a period of one year. Ageing of the cellulose solution before emulsification (resulting in molecular weight reduction) was found to favour the creation of smaller droplets.

  • 29.
    De Jong, Wim H.
    et al.
    RIVM National Institute for Public Health and the Environment, The Netherlands.
    Hoffmann, Sebastian
    Seh consulting + services, Germany.
    Lee, Michelle
    Nelson Laboratories Inc., USA.
    Kandárová, Helena
    MatVitro Life Science Laboratories, Slovakia.
    Pellevoisin, Christian
    EPISKIN, France.
    Haishima, Yuji
    NIHS National Institute of Health Sciences, Japan.
    Rollins, Beau
    Arthrex Inc., USA.
    Zdawczyk, Austin
    NAMSA, USA.
    Willoughby, Jamin
    Cyprotex US LCC, USA.
    Bachelor, Michael
    MatTek Corporation, USA.
    Schatz, Timothy
    American Preclinical Services LLC, USA.
    Skoog, Shelby
    US Food and Drug Administration, USA.
    Parker, Sherry
    WuXi AppTec, USA.
    Sawyer, Anita
    Becton Dickinson, USA.
    Pescio, Paolo
    Eurofins Biolab Srl., Italy.
    Fant, Kristina
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Kim, Kwang-Mahn
    Yonsei University, South Korea.
    Kwon, Jae Sung
    Yonsei University, South Korea.
    Gehrke, Helge
    Eurofins Biopharma, Germany.
    Hofman-Hüther, Hana
    Eurofins Biopharma, Germany.
    Meloni, Morisa
    VitroScreen, Italy.
    Julius, Conrad
    Envigo CRS GmbH, Germany.
    Briotet, Damien
    NAMSA, France.
    Letasiova, Silvia
    MatTek In Vitro Life Science Laboratories, Slovakia.
    Kato, Reiko
    NIHS National Institute of Health Sciences, Japan.
    Miyajima, Atsuko
    NIHS National Institute of Health Sciences, Japan.
    De La Fonteyne, Liset J. J.
    RIVM National Institute for Public Health and the Environment, The Netherlands.
    Videau, Christelle
    EPISKIN, France.
    Tornier, Carine
    EPISKIN, France.
    Turley, Audrey P.
    Nelson Laboratories Inc., USA.
    Christiano, Nicholas
    Arthrex Inc., USA.
    Rollins, Thor S.
    Nelson Laboratories Inc., USA.
    Coleman, Kelly P.
    Medtronic plc, USA.
    Round robin study to evaluate the reconstructed human epidermis (RhE) model as an in vitro skin irritation test for detection of irritant activity in medical device extracts2018Inngår i: Toxicology in Vitro, ISSN 0887-2333, E-ISSN 1879-3177, Vol. 50, s. 439-449Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Assessment of skin irritation is an essential component of the safety evaluation of medical devices. OECD Test Guideline 439 describes the use of reconstructed human epidermis (RhE) as an in vitro test system for classification of skin irritation by neat chemicals. An international round robin study was conducted to evaluate the RhE method for determination of skin irritant potential of medical device extracts. Four irritant polymers and three non-irritant controls were obtained or developed that had demonstrated their suitability to act as positive or negative test samples. The RhE tissues (EpiDerm™ and SkinEthic™ RHE) were dosed with 100 μL aliquots of either saline or sesame oil extract. Incubation times were 18 h (EpiDerm™) and 24 h (SkinEthic™ RHE). Cell viability reduction > 50% was indicative of skin irritation. Both the EpiDerm™ and SkinEthic™ RHE tissues were able to correctly identify virtually all of the irritant polymer samples either in the saline, sesame oil or both solvent extracts. Our results indicate that RhE tissue models can detect the presence of strong skin irritants at low levels in dilute medical device polymer extracts. Therefore, these models may be suitable replacements for the rabbit skin irritation test to support the biological evaluation of medical devices.

  • 30.
    Drake, Henrik
    et al.
    Linnæus University, Sweden.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Sweden.
    Bengtson, Stefan
    Swedish Museum of Natural History, Sweden.
    Heim, Christine
    Georg-August University, Germany.
    Siljeström, Sandra
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Whitehouse, Martin J.
    Swedish Museum of Natural History, Sweden.
    Broman, Curt
    Stockholm University, Sweden.
    Belivanova, Veneta
    Swedish Museum of Natural History, Sweden.
    Åström, Mats E.
    Linnæus University, Sweden.
    Anaerobic consortia of fungi and sulfate reducing bacteria in deep granite fractures2017Inngår i: Nature Communications, E-ISSN 2041-1723, Vol. 8, nr 1, artikkel-id 55Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The deep biosphere is one of the least understood ecosystems on Earth. Although most microbiological studies in this system have focused on prokaryotes and neglected microeukaryotes, recent discoveries have revealed existence of fossil and active fungi in marine sediments and sub-seafloor basalts, with proposed importance for the subsurface energy cycle. However, studies of fungi in deep continental crystalline rocks are surprisingly few. Consequently, the characteristics and processes of fungi and fungus-prokaryote interactions in this vast environment remain enigmatic. Here we report the first findings of partly organically preserved and partly mineralized fungi at great depth in fractured crystalline rock (-740 m). Based on environmental parameters and mineralogy the fungi are interpreted as anaerobic. Synchrotron-based techniques and stable isotope microanalysis confirm a coupling between the fungi and sulfate reducing bacteria. The cryptoendolithic fungi have significantly weathered neighboring zeolite crystals and thus have implications for storage of toxic wastes using zeolite barriers. © 2017 The Author(s).

  • 31.
    Drake, Henrik
    et al.
    Linnæus University, Sweden.
    Roberts, Nick
    British Geological Survey, UK.
    Heim, Christine
    Georg-August University, Germany.
    Whitehouse, Martin
    Swedish Museum of Natural History, Sweden.
    Siljeström, Sandra
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Kooijman, Ellen
    Swedish Museum of Natural History, Sweden.
    Broman, Curt
    Stockholm University, Sweden.
    Ivarsson, Magnus
    Swedish Museum of Natural History, Sweden; University of Southern Denmark, Denmark.
    Åström, Mats
    Linnæus University, Sweden.
    Timing and origin of natural gas accumulation in the Siljan impact structure, Sweden2019Inngår i: Nature Communications, E-ISSN 2041-1723, Vol. 10, nr 1, artikkel-id 4736Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Fractured rocks of impact craters may be suitable hosts for deep microbial communities on Earth and potentially other terrestrial planets, yet direct evidence remains elusive. Here, we present a study of the largest crater of Europe, the Devonian Siljan structure, showing that impact structures can be important unexplored hosts for long-term deep microbial activity. Secondary carbonate minerals dated to 80 ± 5 to 22 ± 3 million years, and thus postdating the impact by more than 300 million years, have isotopic signatures revealing both microbial methanogenesis and anaerobic oxidation of methane in the bedrock. Hydrocarbons mobilized from matured shale source rocks were utilized by subsurface microorganisms, leading to accumulation of microbial methane mixed with a thermogenic and possibly a minor abiotic gas fraction beneath a sedimentary cap rock at the crater rim. These new insights into crater hosted gas accumulation and microbial activity have implications for understanding the astrobiological consequences of impacts. © 2019, The Author(s).

  • 32.
    Ekendahl, Susanne
    et al.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Bark, Mathias
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Engelbrektsson, Johan
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Karlsson, Carl-Anton
    Nordic Paper Bäckhammars Bruk AB, Sweden.
    Niyitegeka, Domitille
    Nordic Paper Bäckhammars Bruk AB, Sweden.
    Strömberg, Niklas
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Energy-efficient outdoor cultivation of oleaginous microalgae at northern latitudes using waste heat and flue gas from a pulp and paper mill2018Inngår i: Algal Research, ISSN 2211-9264, Vol. 31, s. 138-146Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Energy efficient cultivation is the major bottleneck for microalgal biomass production on a large scale and considered very difficult to attain at northern latitudes. In this study an unconventional method for industrial microalgae cultivation for bio-oil production using pulp and paper mill waste resources while harvesting only once a year was performed, mainly in order to investigate the energy efficiency of the process. Algae were cultivated for three months in 2014 in covered pond systems with access to flue gas and waste heat from the industry, and the biomass was recovered as thick sediment sludge after dewatering. The cultivation systems, designed to manage the waste resources, reached a promising photosynthetic efficiency of at most 1.1%, a net energy ratio (NER) of 0.25, and a projected year-round energy biomass yield per area 5.2 times higher than corresponding rapeseed production at the location. Thus, microalgae cultivation was, for the first time, proven energy efficient in a cold continental climate. Energy-rich indigenous communities quickly out-competed the oleaginous monocultures used for inoculation. The recovered biomass had higher heating values of 20–23 MJ kg− 1 and contained 14–19% oil dominated by C16 followed by C18 fatty acids. The cultivation season at 59°15′N, 14°18′E was projected to be efficient for 10 months and waste heat drying of the biomass is suggested for two winter months. The technique is proposed for carbon sequestering and energy storage in the form of microalgal sludge or dry matter for later conversion into biochemicals.

  • 33.
    Farajzadeh Khosroshahi, S.
    et al.
    University of Padova, Italy.
    Olsson, Robin
    RISE - Research Institutes of Sweden, Material och produktion, SICOMP.
    Wysocki, Maciej
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Zaccariotto, M.
    University of Padova, Italy.
    Galvanetto, U.
    University of Padova, Italy.
    Response of a helmet liner under biaxial loading2018Inngår i: Polymer testing, ISSN 0142-9418, E-ISSN 1873-2348, Vol. 72, s. 110-114Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Helmets are the most effective protective item for motorcyclists. The liner of the helmet is the part of the helmet which dissipates most of the impact energy and mitigates the risk of head injuries. It has been proposed that the helmet test standards should include assessment of the helmets for oblique impacts that is not currently addressed in the standards. A conventional uniaxial compression test method is still used for characterization of the helmet liner material. However, compressive tests of EPS foams provide reliable results for normal loading on EPS, but do not provide a realistic result for oblique impacts. Therefore, we carried out experimental tests to measure the response of EPS foams, which are commonly used for helmet liners, under biaxial loading. The result of our experiments show that the shear response of EPS foams is a function of axial compression, and increasing the axial strain leads to increased shear stiffness, and thus higher levels of shear stress. We also showed that including shear-stiffening of EPS in the FE assessment of helmets may change the headform rotational acceleration by 25%. Therefore, such behavior of EPS foams should be included in FE analysis of helmets in the case of oblique impacts for a more realistic assessment of their performance.

  • 34.
    Ferraris, M.
    et al.
    Politecnico di Torino, Italy.
    Perero, S.
    Politecnico di Torino, Italy.
    Ferraris, S.
    Politecnico di Torino, Italy.
    Miola, M.
    Politecnico di Torino, Italy.
    Vernè, E.
    Politecnico di Torino, Italy.
    Skoglund, S.
    KTH Royal Institute of Technology, Sweden.
    Blomberg, Eva
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden.
    Odnevall Wallinder, I.
    KTH Royal Institute of Technology, Sweden.
    Antibacterial silver nanocluster/silica composite coatings on stainless steel2017Inngår i: Applied Surface Science, ISSN 0169-4332, E-ISSN 1873-5584, Vol. 396, s. 1546-1555Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    A coating made of silver nanocluster/silica composites has been deposited, via a radio frequency (RF) co-sputtering technique, for the first time onto stainless steel (AISI 304L) with the aim to improve its antibacterial properties. Different thermal treatments after coating deposition have been applied in order to optimize the coating adhesion, cohesion and its antibacterial properties. Its applicability has been investigated at realistic conditions in a cheese production plant. The physico-chemical characteristics of the coatings have been analyzed by means of different bulk and surface analytical techniques. Field emission scanning electron microscopy (FESEM), X-ray Photoelectron Spectroscopy (XPS), contact angle measurements and atomic force microscopy (AFM) were employed to assess coating morphology, composition, surface roughness, wetting properties, size and local distribution of the nanoparticles within the coating. Tape tests were used to determine the adhesion/cohesion properties of the coating. The amount and time-dependence of released silver in solutions of acetic acid, artificial water, artificial tap water and artificial milk were determined by means of Atomic Absorption Spectroscopy (AAS). The antibacterial effect of the coating was evaluated at different experimental conditions using a standard bacterial strain of Staphylococcus aureus in compliance with National Committee for Clinical Laboratory Standards (NCCLS) and AATCC 147 standards. The Ahearn test was performed to measure the adhesion of bacteria to the coated stainless steel surface compared with a control surface. The antibacterial coating retained its antibacterial activity after thermal treatment up to 450 °C and after soaking in common cleaning products for stainless steel surfaces used for e.g. food applications. The antibacterial capacity of the coating remained at high levels for 1-5 days, and showed a good capacity to reduce the adhesion of bacteria up to 30 days. Only a few percent of silver in the coating was released into acetic acid, even after 10 days of exposure at 40 °C. Most silver (> 90%) remained also in the coating even after 240 h of continuous exposure. Similar observations were made after repeated exposure at 100 °C. Very low levels of released silver in solution were observed in artificial milk. No release of silver nanoparticles was observed either in synthetic tap water or in artificial milk at given conditions. The coating further displayed good antibacterial properties also when tested during working conditions in a cheese production plant.

  • 35.
    Ferreira, Ana R. V.
    et al.
    NOVA University Lisbon, Portugal.
    Haapanen, Janne
    Tampere University of Technology, Finland.
    Mäkelä, Jyrki M.
    Tampere University of Technology, Finland.
    Bratvold, Jon E.
    University of Oslo, Norway.
    Nilsen, Ola
    University of Oslo, Norway.
    Tuominen, Mikko
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Alves, Vitor D.
    University of Lisbon, Portugal.
    Coelhoso, Isabel M.
    NOVA University Lisbon, Portugal.
    Comparison of different coating techniques on the properties of FucoPol films2017Inngår i: International Journal of Biological Macromolecules, ISSN 0141-8130, E-ISSN 1879-0003, Vol. 103, s. 268-274Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Plasma deposition, liquid flame spray (LFS) and atomic layer deposition (ALD) were used to form inorganic coatings in new exopolysaccharide (FucoPol) biodegradable films. Coated films were characterised in terms of surface, optical and barrier properties in order to evaluate their potential use in food packaging. FucoPol films presented dense and homogeneous surface with instant water contact angle of 95̊. Plasma deposition of perfluorohexane (PFH) on FucoPol surface has not shown significant improvement in the hydrophobic behaviour over the time. The FucoPol coating of SiO2 nanoparticles deposited by LFS and plasma deposition of PFH have shown higher instant water contact angle (135°) caused by coating surface roughness, but this hydrophobic behaviour was not stable over time. FucoPol films coated only with TiO2 deposited by ALD and combination of that with plasma deposition of PFH have shown stable water contact angle during time (90̊ and 115̊, respectively), transparency in the same order of magnitude and significantly lower permeability to water vapour (3.45 × 10−11 mol/m s Pa and 3.45 × 10−11 mol/m s Pa when compared to uncoated films with 5.32 × 10−11 mol/m s Pa). Moreover, films coated with TiO2-PFH have also shown a permeability to oxygen of 1.70 × 10−16 molm/m2s Pa which is 67% lower than uncoated films.

  • 36.
    Flys, Olena
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Mätteknik. Halmstad University, Sweden.
    Jarlemark, Per
    RISE - Research Institutes of Sweden (2017-2019), Säkerhet och transport, Mätteknik.
    Petronis, Sarunas
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Stenlund, Patrik
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Rosen, B. -G
    Halmstad University, Sweden.
    Applicability of characterization techniques on fine scale surfaces2018Inngår i: Surface Topography: Metrology and Properties, ISSN 2051-672X, Vol. 6, nr 3, artikkel-id 034015Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In this study, several surface topographies typical for dental implants were evaluated by different measurement techniques. The samples were prepared by machine turning, wet chemical etching and electrochemical polishing of titanium discs. The measurement techniques included an atomic force microscope (AFM), coherence scanning interferometer (CSI) and a 3D stereo scanning electron microscope (SEM). The aim was to demonstrate and discuss similarities and differences in the results provided by these techniques when analyzing submicron surface topographies. The estimated surface roughness parameters were not directly comparable since the techniques had different surface spatial wavelength band limits. However, the comparison was made possible by applying a 2D power spectral density (PSD) function. Furthermore, to simplify the comparison, all measurements were characterized using the ISO 25178 standard parameters. Additionally, a Fourier transform was applied to calculate the instrument transfer function in order to investigate the behavior of CSI at different wavelength ranges. The study showed that 3D stereo SEM results agreed well with AFM measurements for the studied surfaces. Analyzed surface parameter values were in general higher when measured by CSI in comparison to both AFM and 3D stereo SEM results. In addition, the PSD analysis showed a higher power spectrum density in the lower frequency range 10-2-10-1 μm-1 for the CSI compared with the other techniques.

  • 37.
    Fornaro, Teresa
    et al.
    Geophysical Laboratory of the Carnegie Institution for Science, USA; NAF-Astrophysical Observatory of Arcetri, Italy.
    Boosman, Arjen
    Utrecht University, The Netherlands.
    Brucato, John R.
    NAF-Astrophysical Observatory of Arcetri, Italy.
    ten Kate, Inge Loes
    Utrecht University, The Netherlands.
    Siljeström, Sandra
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Poggiali, Giovanni
    NAF-Astrophysical Observatory of Arcetri, Italy; Università degli Studi di Firenze, Italy.
    Steele, Andrew
    Geophysical Laboratory of the Carnegie Institution for Science, USA.
    Hazen, Robert M.
    Geophysical Laboratory of the Carnegie Institution for Science, USA.
    UV irradiation of biomarkers adsorbed on minerals under Martian-like conditions: Hints for life detection on Mars2018Inngår i: Icarus, ISSN 0019-1035, E-ISSN 1090-2643, Vol. 313, s. 38-60Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Laboratory simulations of Martian conditions are essential to develop quantitative models for the survival of organic biomarkers for future Mars exploration missions. In this work, we report the results of ultraviolet (UV) irradiation processing of biomarkers adsorbed on minerals under Martian-like conditions. Specifically, we prepared Mars soil analogues by doping forsterite, lizardite, antigorite, labradorite, natrolite, apatite and hematite minerals with organic compounds considered as potential biomarkers of extant terrestrial life such as the nucleotides adenosine monophosphate (AMP) and uridine monophosphate (UMP). We characterized such Mars soil analogues by means of Time-of-Flight Secondary Ion Mass Spectrometry (ToF-SIMS), Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) and Confocal Raman Imaging Spectroscopy (CRIS), in order to get insights into the specific molecule-mineral interactions and explore the capabilities of different techniques to reveal diagnostic features of these biomarkers. Then, we performed irradiation experiments in the mid-UV spectral region under simulated Martian conditions and under terrestrial ambient conditions for comparison, monitoring the degradation process through DRIFTS. We observed that degradation under Martian-like conditions occurs much slower than in terrestrial ambient conditions. The minerals labradorite and natrolite mainly promote photodegradation of nucleotides, hematite and forsterite exhibit an intermediate degrading effect, while apatite, lizardite and antigorite do not show any significant catalytic effect on the degradation of the target organic species.

  • 38.
    Fromell, Karin
    et al.
    Uppsala University, Sweden.
    Yang, Yi
    University of Gothenburg, Sweden.
    Nilsson Ekdahl, Kristina
    Linnaeus University, Sweden.
    Nilsson, Bo
    Linnaeus University, Sweden.
    Berglin, Mattias
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Elwing, Hans
    University of Gothenburg, Sweden.
    Absence of conformational change in complement factor 3 and factor XII adsorbed to acrylate polymers is related to a high degree of polymer backbone flexibility2017Inngår i: Biointerphases, ISSN 1934-8630, E-ISSN 1559-4106, Vol. 12, nr 2, artikkel-id 02D417Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    In previous investigations, the authors have examined the adsorption of albumin, immunoglobulin, and fibrinogen to a series of acrylate polymers with different backbone and side-group flexibility. The authors showed that protein adsorption to acrylates with high flexibility, such as poly(lauryl methacrylate) (PLMA), tends to preserve native conformation. In the present study, the authors have continued this work by examining the conformational changes that occur during the binding of complement factor 3 (C3) and coagulation factor XII (FXII). Native C3 adsorbed readily to all solid surfaces tested, including a series of acrylate surfaces of varying backbone flexibility. However, a monoclonal antibody recognizing a "hidden" epitope of C3 (only exposed during C3 activation or denaturation) bound to the C3 on the rigid acrylate surfaces or on polystyrene (also rigid), but not to C3 on the flexible PLMA, indicating that varying degrees of conformational change had occurred with binding to different surfaces. Similarly, FXII was activated only on the rigid poly(butyl methacrylate) surface, as assessed by the formation of FXIIa-antithrombin (AT) complexes; in contrast, it remained in its native form on the flexible PLMA surface. The authors also found that water wettability hysteresis, defined as the difference between the advancing and receding contact angles, was highest for the PLMA surface, indicating that a dynamic change in the interface polymer structure may help protect the adsorbed protein from conformational changes and denaturation.

  • 39.
    Földváry, Veronika
    et al.
    Slovak University of Technology, Slovakia.
    Bekö, Gabriel
    DTU Technical University of Denmark, Denmark.
    Langer, Sarka
    IVL Swedish Environmental Research Institute, Sweden; Chalmers University of Technology, Sweden.
    Arrhenius, Karine
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Petráš, Dusan
    Slovak University of Technology, Slovakia.
    Effect of energy renovation on indoor air quality in multifamily residential buildings in Slovakia2017Inngår i: Building and Environment, ISSN 0360-1323, E-ISSN 1873-684X, Vol. 122, s. 363-372Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Buildings are responsible for a substantial portion of the global energy consumption. Most of the multifamily residential buildings built in the 20th century in Central and Eastern Europe do not satisfy the current requirements on energy efficiency. Nationwide measures taken to improve the energy efficiency of these buildings rarely consider their impact on the indoor air quality (IAQ). The objective of the present study was to evaluate the impact of simple energy renovation on IAQ, air exchange rates (AER) and occupant satisfaction in Slovak residential buildings. Three pairs of identical naturally ventilated multifamily residential buildings were examined. One building in each pair was newly renovated, the other was in its original condition. Temperature, relative humidity (RH) and the concentration of carbon dioxide (CO2) were measured in 94 apartments (57%) during one week in the winter. A questionnaire related to perceived air quality, sick building syndrome symptoms and airing habits was filled by the occupants. In a companion experiment, the IAQ was investigated in 20 apartments (50%) of a single residential building before and after its renovation. In this experiment, concentrations of nitrogen dioxide (NO2), formaldehyde and total and individual volatile organic compounds (VOC) were also measured. CO2 concentrations were significantly higher and AERs were lower in the renovated buildings. Formaldehyde concentrations increased after renovation and were positively correlated with CO2 and RH. Energy renovation was associated with lower occupant satisfaction with IAQ. Energy retrofitting efforts should be complemented with improved ventilation in order to avoid adverse effects on IAQ.

  • 40.
    Gavilán, Helena
    et al.
    CSIC Instituto de Ciencia de Materiales de Madrid, Spain.
    Kowalski, Anja
    Micromod Partikeltechnologie GmbH, Germany.
    Heinke, David
    NanoPET Pharma GmbH, Germany.
    Sugunan, Abhilash
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Sommertune, Jens
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Varón, Miriam
    DTU Technical University of Denmark, Denmark.
    Bogart, Lara K.
    UCL University College London, UK.
    Posth, Oliver
    PTB Physikalisch-Technische Bundesanstalt, Germany.
    Zeng, Lunjie
    Chalmers University of Technology, Sweden.
    González-Alonso, David
    University of Cantabria, Spain.
    Balceris, Chrsitoph
    TU Braunschweig, Germany.
    Fock, Jeppe
    DTU Technical University of Denmark, Denmark.
    Wetterskog, Erik
    Uppsala University, Sweden.
    Frandsen, Cathrine
    DTU Technical University of Denmark, Denmark.
    Gehrke, Nicole
    NanoPET Pharma GmbH, Germany.
    Grüttner, Cordula
    Micromod Partikeltechnologie GmbH, Germany.
    Fornara, Andrea
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Ludwig, Frank
    TU Braunschweig, Germany.
    Veintemillas-Verdaguer, Sabino
    CSIC Instituto de Ciencia de Materiales de Madrid, Spain.
    Johansson, Christer
    RISE - Research Institutes of Sweden, ICT, Acreo.
    Morales, M. Puerto
    CSIC Instituto de Ciencia de Materiales de Madrid, Spain.
    Colloidal Flower-Shaped Iron Oxide Nanoparticles: Synthesis Strategies and Coatings2017Inngår i: Particle & particle systems characterization, ISSN 0934-0866, E-ISSN 1521-4117, Vol. 34, nr 7, artikkel-id 1700094Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The assembly of magnetic cores into regular structures may notably influence the properties displayed by a magnetic colloid. Here, key synthesis parameters driving the self-assembly process capable of organizing colloidal magnetic cores into highly regular and reproducible multi-core nanoparticles are determined. In addition, a self-consistent picture that explains the collective magnetic properties exhibited by these complex assemblies is achieved through structural, colloidal, and magnetic means. For this purpose, different strategies to obtain flower-shaped iron oxide assemblies in the size range 25–100 nm are examined. The routes are based on the partial oxidation of Fe(OH)2, polyol-mediated synthesis or the reduction of iron acetylacetonate. The nanoparticles are functionalized either with dextran, citric acid, or alternatively embedded in polystyrene and their long-term stability is assessed. The core size is measured, calculated, and modeled using both structural and magnetic means, while the Debye model and multi-core extended model are used to study interparticle interactions. This is the first step toward standardized protocols of synthesis and characterization of flower-shaped nanoparticles.

  • 41.
    Gebbie, Matthew A.
    et al.
    Stanford University, USA.
    Smith, Alexander M.
    University of Oxford, UK.
    Dobbs, Howard A.
    University of California, USA.
    Lee, Alpha A.
    Harvard University, USA.
    Warr, Gregory G.
    University of Sydney, Australia.
    Banquy, Xavier
    Universite de Montreal, Canada.
    Valtiner, Markus
    Max Planck Institut fur Eisenforschung GmbH, Germany.
    Rutland, Mark W.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. KTH Royal Institute of Technology, Sweden .
    Israelachvili, Jacob N.
    University of California, USA.
    Perkin, Susan
    University of Oxford, UK.
    Atkin, Rob
    University of Newcastle, Australia.
    Long range electrostatic forces in ionic liquids2017Inngår i: Chemical Communications, ISSN 1359-7345, E-ISSN 1364-548X, Vol. 53, nr 7, s. 1214-1224Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Ionic liquids are pure salts that are liquid under ambient conditions. As liquids composed solely of ions, the scientific consensus has been that ionic liquids have exceedingly high ionic strengths and thus very short Debye screening lengths. However, several recent experiments from laboratories around the world have reported data for the approach of two surfaces separated by ionic liquids which revealed remarkable long range forces that appear to be electrostatic in origin. Evidence has accumulated demonstrating long range surface forces for several different combinations of ionic liquids and electrically charged surfaces, as well as for concentrated mixtures of inorganic salts in solvent. The original interpretation of these forces, that ionic liquids could be envisioned as “dilute electrolytes,” was controversial, and the origin of long range forces in ionic liquids remains the subject of discussion. Here we seek to collate and examine the evidence for long range surface forces in ionic liquids, identify key outstanding questions, and explore possible mechanisms underlying the origin of these long range forces. Long range surface forces in ionic liquids and other highly concentrated electrolytes hold diverse implications from designing ionic liquids for energy storage applications to rationalizing electrostatic correlations in biological self-assembly.

  • 42.
    Goesmann, Fred
    et al.
    Max-Planck-Institut für Sonnensystemforschung, Germany.
    Brinckerhoff, William B.
    NASA GSFC, USA.
    Raulin, Francoise
    CNRS, France.
    Goetz, Walter
    Max-Planck-Institut für Sonnensystemforschung, Germany.
    Danell, Ryan M.
    Danell Consulting, USA.
    Getty, Stephanie A.
    NASA GSFC, USA.
    Siljeström, Sandra
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Mißbach, Helge
    Max-Planck-Institut für Sonnensystemforschung, Germany.
    Steininger, Harald
    Max-Planck-Institut für Sonnensystemforschung, Germany.
    Arevalo, Ricardo D.
    NASA GSFC, USA.
    Buch, Arnaud
    École Centrale Paris, France.
    Freissinet, Caroline
    LATMOS IPSL, France.
    Grubisic, Andrei
    NASA GSFC, USA; University of Maryland, USA.
    Meierhenrich, Uwe J.
    Université de Nice-Sophia Antipolis, France.
    Pinnick, Veronica T.
    NASA GSFC, USA.
    Stalport, Fabien
    CNRS, France.
    Szopa, Cyriel
    LATMOS IPSL, France; Institut Universitaire de France, France.
    Vago, Jorge L.
    ESA, The Netherlands.
    Lindner, Robert
    ESA, The Netherlands.
    Schulte, Mitchell D.
    NASA Headquarters, USA.
    Brucato, John R.
    INAF Astrophysical Observatory of Arcetri, Italy.
    Glavin, Danil P.
    NASA GSFC, USA.
    Grand, Noel
    CNRS, France.
    Li, Xiang
    NASA GSFC, USA; University of Maryland, USA.
    Van Amerom, Frisco H. W.
    Mini-Mass Consulting, USA.
    The Mars Organic Molecule Analyzer (MOMA) Instrument: Characterization of Organic Material in Martian Sediments2017Inngår i: Astrobiology, ISSN 1531-1074, E-ISSN 1557-8070, Vol. 17, nr 6-7, s. 655-685Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The Mars Organic Molecule Analyzer (MOMA) instrument onboard the ESA/Roscosmos ExoMars rover (to launch in July, 2020) will analyze volatile and refractory organic compounds in martian surface and subsurface sediments. In this study, we describe the design, current status of development, and analytical capabilities of the instrument. Data acquired on preliminary MOMA flight-like hardware and experimental setups are also presented, illustrating their contribution to the overall science return of the mission..

  • 43.
    Grady, Moniqa M
    et al.
    Open University, UK ; The Natural History Museum, UK.
    Wright, Ian
    Open University, UK.
    Engrand, Cecile
    University Paris Sud, France.
    Siljeström, Sandra
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    The Rosetta mission and the chemistry of organic species in comet 67P/Churyumov-Gerasimenko2018Inngår i: Elements, ISSN 1811-5209, E-ISSN 1811-5217, Vol. 14, nr 2, s. 95-100Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Comets are regarded as probably the most primitive of solar system objects, preserving a record of the materials from which the solar system aggregated. Key amongst their components are organic compounds - molecules that may trace their heritage to the interstellar medium from which the protosolar nebula eventually emerged. The most recent cometary space mission, Rosetta, carried instruments designed to characterize, in unprecedented detail, the organic species in comet 67P/Churyumov-Gerasimenko (67P). Rosetta was the first mission to match orbits with a comet and follow its evolution over time, and also the first mission to land scientific instruments on a comet surface. Results from the mission revealed a greater variety of molecules than previously identified and indicated that 67P contained both primitive and processed organic entities. 

  • 44.
    Granskog, Viktor
    et al.
    KTH Royal Institute of Technology, Sweden.
    García-Gallego, Sandra
    KTH Royal Institute of Technology, Sweden.
    von Kieseritzky, Johanna
    Karolinska Institutet, Sweden.
    Rosendahl, Jennifer
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Stenlund, Patrik
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Zhang, Yuning
    KTH Royal Institute of Technology, Sweden.
    Petronis, Sarunas
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Lyvén, Benny
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Arner, Marianne
    Karolinska Institutet, Sweden.
    Håkansson, Joakim
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material.
    Malkoch, Michael
    KTH Royal Institute of Technology, Sweden.
    High-Performance Thiol–Ene Composites Unveil a New Era of Adhesives Suited for Bone Repair2018Inngår i: Advanced Functional Materials, ISSN 1616-301X, E-ISSN 1616-3028, Vol. 28, nr 26, artikkel-id 1800372Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The use of adhesives for fracture fixation can revolutionize the surgical procedures toward more personalized bone repairs. However, there are still no commercially available adhesive solutions mainly due to the lack of biocompatibility, poor adhesive strength, or inadequate fixation protocols. Here, a surgically realizable adhesive system capitalizing on visible light thiol–ene coupling chemistry is presented. The adhesives are carefully designed and formulated from a novel class of chemical constituents influenced by dental resin composites and self-etch primers. Validation of the adhesive strength is conducted on wet bone substrates and accomplished via fiber-reinforced adhesive patch (FRAP) methodology. The results unravel, for the first time, on the promise of a thiol–ene adhesive with an unprecedented shear bond strength of 9.0 MPa and that surpasses, by 55%, the commercially available acrylate dental adhesive system Clearfil SE Bond of 5.8 MPa. Preclinical validation of FRAPs on rat femur fracture models details good adhesion to the bone throughout the healing process, and are found biocompatible not giving rise to any inflammatory response. Remarkably, the FRAPs are found to withstand loads up to 70 N for 1000 cycles on porcine metacarpal fractures outperforming clinically used K-wires and match metal plates and screw implants.

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  • 45.
    Gren, Johan A.
    et al.
    Lund University, Sweden.
    Sjövall, Peter
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Eriksson, Mats E.
    Lund University, Sweden.
    Sylvestersen, Rene L.
    MUSERUM, Denmark.
    Marone, Frederica
    Paul Scherrer Institute, Switzerland.
    Sigfridsson Clauss, Kajsa G. V.
    MAX IV Laboratory, Sweden.
    Taylor, Gavin J.
    Lund University, Sweden.
    Carlson, Stefan
    MAX IV Laboratory, Sweden.
    Uvdal, Per
    Lund University, Sweden.
    Lindgren, Johan
    Lund University, Sweden.
    Molecular and microstructural inventory of an isolated fossil bird feather from the Eocene Fur Formation of Denmark2017Inngår i: Palaeontology, ISSN 0031-0239, E-ISSN 1475-4983, Vol. 60, nr 1, s. 73-90Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    An isolated, yet virtually intact contour feather (FUM-1980) from the lower Eocene Fur Formation of Denmark was analysed using multiple imaging and molecular techniques, including field emission gun scanning electron microscopy (FEG-SEM), X-ray absorption spectroscopy and time-of-flight secondary ion mass spectrometry (ToF-SIMS). Additionally, synchrotron radiation X-ray tomographic microscopy (SRXTM) was employed in order to produce a digital reconstruction of the fossil. Under FEG-SEM, the proximal, plumulaceous part of the feather revealed masses of ovoid microstructures, about 1.7 μm long and 0.5 μm wide. Microbodies in the distal, pennaceous portion were substantially smaller (averaging 0.9 × 0.2 μm), highly elongate, and more densely packed. Generally, the microbodies in both the plumulaceous and pennaceous segments were aligned along the barbs and located within shallow depressions on the exposed surfaces. Biomarkers consistent with animal eumelanins were co-localized with the microstructures, to suggest that they represent remnant eumelanosomes (i.e. eumelanin-housing cellular organelles). Additionally, ToF-SIMS analysis revealed the presence of sulfur-containing organics – potentially indicative of pheomelanins – associated with eumelanin-like compounds. However, since there was no correlation between melanosome morphology and sulfur content, we conclude these molecular structures derive from diagenetically incorporated sulfur rather than pheomelanin. Melanosomes corresponding roughly in both size and morphology with those in the proximal part of FUM-1980 are known from contour feathers of extant parrots (Psittaciformes), an avian clade that has previously been reported from the Fur Formation.

  • 46.
    Hakonen, Aron
    et al.
    RISE - Research Institutes of Sweden. Sensor Visions AB, Sweden.
    Karlsson, Anders
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Lindman, Lena
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Büker, Oliver
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Arrhenius, Karine
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Particles in fuel-grade Liquefied Natural Gas2018Inngår i: Journal of Natural Gas Science and Engineering, ISSN 1875-5100, E-ISSN 2212-3865, Vol. 55, s. 350-353Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The utilization of Liquefied Natural Gas (LNG) in the heavy-duty transport sector is a convenient and cost-effective step towards a sustainable future. However, there are questions regarding LNG fuel quality and destructive particles for engines. Basically nothing is known about particles in the commercial LNG being fueled today. The gravimetric and SEM-EDX results here demonstrates that there are precarious metal and silicon dioxide particles in fuel-grade LNG that can clog and erode engine parts. Considering these results further research in the direction of this study, including standardized method development, is highly motivated.

  • 47.
    Hakonen, Aron
    et al.
    Sensor Visions AB, Sweden.
    Strömberg, Niklas
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Fluorescence and naked-eye detection of Pb2+ in drinkingwater using a low-cost ionophore based sensing scheme2018Inngår i: Chemosensors, ISSN 2227-9040, Vol. 6, nr 4, artikkel-id 51Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Drinking water contamination of lead from various environmental sources, leaching consumer products, and intrinsic water-pipe infrastructure is still today a matter of great concern. Therefore, new highly sensitive and convenient Pb2+ measurement schemes are necessary, especially for in-situ measurements at a low cost. Within this work dye/ionophore/Pb2+ co-extraction and effective water phase de-colorization was utilized for highly sensitive lead measurements and sub-ppb naked-eye detection. A low-cost ionophore Benzo-18-Crown-6-ether was used, and a simple test-tube mix and separate procedure was developed. Instrumental detection limits were in the low ppt region (LOD = 3, LOQ = 10), and naked-eye detection was 500 ppt. Note, however, that this sensing scheme still has improvement potential as concentrations of fluorophore and ionophore were not optimized. Artificial tap-water samples, leached by a standardized method, demonstrated drinking water application. Implications for this method are convenient in-situ lead ion measurements.

  • 48.
    Hakonen, Aron
    et al.
    RISE - Research Institutes of Sweden (2017-2019), Biovetenskap och material, Kemi och material. Chalmers University of Technology, Sweden.
    Wang, Fengshao
    University of Science and Technology of China, China.
    Andersson, Per Ola
    Uppsala University, Sweden; FOI Swedish Defense Research Agency, Sweden.
    Wingfors, Håkan
    FOI Swedish Defense Research Agency, Sweden.
    Rindzevicius, Tomas
    DTU Technical University of Denmark, Denmark.
    Schmidt, Michael S.
    DTU Technical University of Denmark, Denmark.
    Soma, Venugopal Roi
    University of Hyderabad, India.
    Xu, Shicai
    Dezhou University, China.
    Li, YingQi
    University of Science and Technology of China, China.
    Boisen, Anja
    DTU Technical University of Denmark, Denmark.
    Wu, HengAn
    University of Science and Technology of China, China.
    Hand-Held Femtogram Detection of Hazardous Picric Acid with Hydrophobic Ag Nanopillar SERS Substrates and Mechanism of Elasto-Capillarity2017Inngår i: ACS Sensors, E-ISSN 2379-3694, Vol. 2, nr 2, s. 198-202Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Picric acid (PA) is a severe environmental and security risk due to its unstable, toxic, and explosive properties. It is also challenging to detect in trace amounts and in situ because of its highly acidic and anionic character. Here, we assess sensing of PA under nonlaboratory conditions using surface-enhanced Raman scattering (SERS) silver nanopillar substrates and hand-held Raman spectroscopy equipment. The advancing elasto-capillarity effects are explained by molecular dynamics simulations. We obtain a SERS PA detection limit on the order of 20 ppt, corresponding attomole amounts, which together with the simple analysis methodology demonstrates that the presented approach is highly competitive for ultrasensitive analysis in the field.

  • 49.
    Haloua, Frederique
    et al.
    LNE Laboratoire national de métrologie et d'essais, France.
    Bacquart, Thomas
    NPL National Physical Laboratory, UK.
    Arrhenius, Karine
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material.
    Delobelle, Benoit
    MAHYTEC, France.
    Ent, Hugo
    VSL Van Swinden Laboratorium, The Netherlands.
    Metrology for hydrogen energy applications: a project to address normative requirements2018Inngår i: Measurement science and technology, ISSN 0957-0233, E-ISSN 1361-6501, Vol. 29, nr 3, artikkel-id Special Section on the 18th International Congress of Metrology (CIM 2017)Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    Hydrogen represents a clean and storable energy solution that could meet worldwide energy demands and reduce greenhouse gases emission. The joint research project (JRP) ‘Metrology for sustainable hydrogen energy applications’ addresses standardisation needs through pre- and co-normative metrology research in the fast emerging sector of hydrogen fuel that meet the requirements of the European Directive 2014/94/EU by supplementing the revision of two ISO standards that are currently too generic to enable a sustainable implementation of hydrogen. The hydrogen purity dispensed at refueling points should comply with the technical specifications of ISO 14687-2 for fuel cell electric vehicles. The rapid progress of fuel cell technology now requires revising this standard towards less constraining limits for the 13 gaseous impurities. In parallel, optimized validated analytical methods are proposed to reduce the number of analyses. The study aims also at developing and validating traceable methods to assess accurately the hydrogen mass absorbed and stored in metal hydride tanks; this is a research axis for the revision of the ISO 16111 standard to develop this safe storage technique for hydrogen. The probability of hydrogen impurity presence affecting fuel cells and analytical techniques for traceable measurements of hydrogen impurities will be assessed and new data of maximum concentrations of impurities based on degradation studies will be proposed. Novel validated methods for measuring the hydrogen mass absorbed in hydrides tanks AB, AB2 and AB5 types referenced to ISO 16111 will be determined, as the methods currently available do not provide accurate results. The outputs here will have a direct impact on the standardisation works for ISO 16111 and ISO 14687-2 revisions in the relevant working groups of ISO/TC 197 ‘Hydrogen technologies’.

  • 50.
    Hannestad, Jonas
    et al.
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. Chalmers University of Technology, Sweden.
    Höök, Fredrik
    Chalmers University of Technology, Sweden.
    Sjövall, Peter
    RISE - Research Institutes of Sweden, Biovetenskap och material, Kemi och material. Chalmers University of Technology, Sweden.
    Nanometer-scale molecular organization in lipid membranes studied by time-of-flight secondary ion mass spectrometry2018Inngår i: Biointerphases, ISSN 1934-8630, E-ISSN 1559-4106, Vol. 13, nr 3, artikkel-id 03B408Artikkel i tidsskrift (Fagfellevurdert)
    Abstract [en]

    The organization of lipid membranes plays an important role in a wide range of biological processes at different length scales. Herein, the authors present a procedure based on time-of-flight secondary ion mass spectrometry (ToF-SIMS) to characterize the nanometer-scale ordering of lipids in lipid membrane structures on surfaces. While ToF-SIMS is a powerful tool for label-free analysis of lipid-containing samples, its limited spatial resolution prevents in-depth knowledge of how lipid properties affect the molecular assembly of the membrane. The authors overcome this limitation by measuring the formation of lipid dimers, originating in the same nanometer-sized primary ion impact areas. The lipid dimers reflect the local lipid environment and thus allow us to characterize the membrane miscibility on the nanometer level. Using this technique, the authors show that the chemical properties of the constituting lipids are critical for the structure and organization of the membrane on both the nanometer and micrometer length scales. Our results show that even at lipid surface compositions favoring two-phase systems, lipids are still extracted from solid, gel phase, domains into the surrounding fluid supported lipid bilayer surrounding the gel phase domains. The technique offers a means to obtain detailed knowledge of the chemical composition and organization of lipid membranes with potential application in systems where labeling is not possible, such as cell-derived supported lipid bilayers.

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