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  • 1. A. Hosseini, V.
    et al.
    Karlsson, L.
    Örnek, Cem
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. Swerea KIMAB AB.
    Reccagni, P.
    Wessman, S.
    Engelberg, D.
    Microstructure and functionality of a uniquely graded super duplex stainless steel designed by a novel arc heat treatment method2018In: Materials Characterization, ISSN 1044-5803, E-ISSN 1873-4189, Vol. 139, p. 390-400Article in journal (Refereed)
    Abstract [en]

    A novel arc heat treatment technique was applied to design a uniquely graded super duplex stainless steel (SDSS), by subjecting a single sample to a steady state temperature gradient for 10 h. A new experimental approach was used to map precipitation in microstructure, covering aging temperatures of up to 1430 °C. The microstructure was characterized and functionality was evaluated via hardness mapping. Nitrogen depletion adjacent to the fusion boundary depressed the upper temperature limit for austenite formation and influenced the phase balance above 980 °C. Austenite/ferrite boundaries deviating from Kurdjumov–Sachs orientation relationship (OR) were preferred locations for precipitation of σ at 630–1000 °C, χ at 560–1000 °C, Cr2N at 600–900 °C and R between 550 °C and 700 °C. Precipitate morphology changed with decreasing temperature; from blocky to coral-shaped for σ, from discrete blocky to elongated particles for χ, and from polygonal to disc-shaped for R. Thermodynamic calculations of phase equilibria largely agreed with observations above 750 °C when considering nitrogen loss. Formation of intermetallic phases and 475 °C-embrittlement resulted in increased hardness. A schematic diagram, correlating information about phase contents, morphologies and hardness, as a function of exposure temperature, is introduced for evaluation of functionality of microstructures.

  • 2.
    Abbasi, M.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Backstrom, J.
    Mid Sweden Univ, FSCN Mat Phys, Dept Nat Sci, SE-85170 Sundsvall, Sweden..
    Cornell, Ann M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Applied Electrochemistry.
    Fabrication of Spin-Coated Ti/TiHx/Ni-Sb-SnO2 Electrode: Stability and Electrocatalytic Activity2018In: Journal of the Electrochemical Society, ISSN 0013-4651, E-ISSN 1945-7111, Vol. 165, no 9, p. H568-H574Article in journal (Refereed)
    Abstract [en]

    A novel three-layer anode having the composition Ti/TiHx/Ni-Sb-SnO2 (Ti/TiHx/NATO) was successfully prepared by a spin-coating and pyrolysis process aiming at a long service lifetime and good electrocatalytic properties for ozone formation. The TiHx as an interlayer was produced by electrochemical cathodic reduction of a coated layer of the TiOx on the titanium substrate. Spin coating and thermal decomposition were used to deposit the Sn-Sb-Ni precursor on the surface of the prepared Ti/TiHx electrode. Cyclic and linear scanning voltammetry, Raman spectroscopy, scanning electron microscopy (SEM) and X-ray diffraction (XRD) were used to reveal the electrode performance and morphology. Results show that the onset potential for the oxygen evolution reaction (OER) of Ti/TiHx /NATO is higher than for Ti/NATO. They also indicate that the service lifetime of the Ti/TiHx/NATO is twice as long as the Ti/NATO at a current density of 50 mA.cm(-2) at room temperature. Electrochemical ozone generation and degradation of the methylene blue were investigated to confirm selectivity and activity of the electrodes. After 5 min electrolysis, a current efficiency for ozone generation of 56% was obtained the electrode with TiHx while 38% was obtained on Ti/NATO under same conditions. The results also confirm that the Ti/TiH x /NATO has a higher kinetic rate constant and decolorization efficiency for removal of the methylene blue compare to the Ti/NATO. The rate constant for the pseudo-first ordered reaction of methylene blue degradation showed high values of 350 x 10(-3) min(-1) for Ti/NATO and 440 x 10(-3) min(-1) for Ti/TiHx/NATO. 

  • 3.
    Abdel Alim, Richard
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Formation of Soft Paticles in Drop-in Fuels2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    As the mission to the decrease global warming and phase out highly pollutingenvironmental practices globally, regulations including Euro 6 and policies generated by theUnited Nations Framework Convention on Climate Change (UNFCCC) are pushing companiesto be more innovative when it comes to their energy sources. These regulations involve manyfactors related to the cleanliness of the fuel and produced emissions, for example, propertiesof the fuels such as sulfur content, ash content, water content, and resulting emission valuesof Carbon dioxide (CO2) and Nitrogen Oxides (NOx). Furthermore, Sweden has set achallenging target of a fossil-fuel-independent vehicle fleet by 2030 and no net greenhousegasemissions by 2050.One way to cut down on the polluting properties in the fuel, as well as weakening thedependence on fossil fuel based fuel includes utilizing higher blending ratios of biofuels in thetransport sector. This transition to biofuels comes with many challenges to the transportindustry due to higher concentrations of these new fuels leads to clogging of the filters in theengine, as well as, internal diesel injector deposits (IDIDs) that produce injector fouling. Thisclogging of the filters leads to lower performance by the engines which leads to higher repairtimes (uptime) and less time on the road to transport goods. The formation of these softparticles at the root of the clogging issue is a pivotal issue because the precise mechanismsbehind their formation are highly unknown. Scania, a leader in the Swedish automotiveindustry, is very interested in figuring out what mechanisms are the most influential in theformation of these particles in the engine. Understanding the key mechanisms would allowScania to make appropriate adjustments to the fuel or the engines to ensure more time onthe road and less maintenance.There are many conditions known to be possible causes of the formation of softparticles in engines such as water content, ash content, and temperature. After generatingsoft particles using a modified accelerated method, particles were analyzed using infraredtechnology (RTX-FTIR) and a Scanning Electric Microscope (SEM-EDX). Many differentexperiments were performed to be able to make a conclusion as to which mechanisms weremost influential including temperature, time, water, air, and oil. The combination of agingbiofuels (B100, B10, HVO) with metals, and water produced the largest amount of particlesfollowed by aging the biofuels with aged oil, metals, and water. Aging the fuels with aged oilincreased particles, meanwhile the addition of water prevented particle production possiblydue to additives. B100 produced the highest amount of particles when aged with Copper, B10with Brass, and HVO with Iron.

  • 4.
    Abdel-Magied, Ahmed F.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Nasser Abdelhamid, Hani
    Ashour, Radwa M.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Hierarchical porous zeolitic imidazolate framework nanoparticles for efficient adsorption of rare-earth elements2019In: Microporous and Mesoporous Materials, ISSN 1387-1811, E-ISSN 1873-3093, Vol. 278, p. 175-184Article in journal (Refereed)
  • 5.
    Abdirahman Ahmed, Fatima
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Reologistudie av vattenbaserade industrifärger2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The rheological properties of water-based paint have been studied and the parameters that were investigated were mobility, viscoelasticity, sagging and levelling. The methods that arepresented in this study can predict sagging before the paint is applied on a vertical surface. The purpose of this study is to understand how different paints behave when sprayed on a vertical surface. The main goal in this study is to develop a method that can predict sagging when the wet condition is 300 μm.

    The rheometer gave measurement data that could be graded on a scale. Every paint had a value on this graded scale. A "Shear Rate Loop Test" was used to grade the paints after a graphical analysis. The development on the graded scale gives the right information whether the paint sags or not.

    Different types of oscillation tests were performed and these tests were 3ITT, amplitude sweep and frequency sweep. Elastic and viscous behaviour were measured and they illustrated what behaviour was dominating in the paints. 28 water-based paints were analysed and the methods for these paints can predict how they flow on a vertical surface.

  • 6.
    Abdirahman, Khalid
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Förnberg, Sebastian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Styrsystem för solcellsladdade batterier2018Independent thesis Basic level (university diploma), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The use of solar cells is continuously increasing in Sweden and the powergenerated by the solar cells is usually stored in lead acid batteries. These batterieshave a bad impact on the environment as much energy and environmentallyhazardous materials like lead and sulfuric acid are required to manufacture thesebatteries. Östersjökompaniet AB and many of its customers realize the importanceof sustainable thinking and were interested in knowing if it was possible tomaximize the lifetime of these batteries. During the course of the work, differentmethods of battery charging and discharging were analyzed that could affect thebatteries lifetime and how to take care of them to optimize them. A chargecontroller was used to optimize the charge of the battery. To calculate theremaining state of charge in the battery, the Extended voltmeter method was used.A prototype that was able to charge the batteries optimally, warn when the batterycapacity became too low, and a user-friendly application for battery monitoring wasdesigned. The calculated lifetime of a battery is not an exact science. According tostudies the lifetime of a battery can be doubled if it is c

  • 7. Abtahi, Farhad
    et al.
    Forsman, Mikael
    Diaz-Olivazrez, Jose A.
    KTH, School of Technology and Health (STH).
    Yang, Liyun
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Ergonomics.
    Lu, Ke
    KTH, School of Technology and Health (STH).
    Eklund, Jörgen
    KTH, School of Technology and Health (STH).
    Lindecrantz, Kaj
    KTH, School of Technology and Health (STH).
    Seoane, Fernando
    Teriö, Heikki
    Mediavilla Martinez, Cesar
    Aso, Santiago
    Tiemann, Christian
    Big Data & Wearable Sensors Ensuring Safety and Health @Work2017In: GLOBAL HEALTH 2017, The Sixth International Conference on Global Health Challenges, 2017Conference paper (Refereed)
    Abstract [en]

    —Work-related injuries and disorders constitute a major burden and cost for employers, society in general and workers in particular. We@Work is a project that aims to develop an integrated solution for promoting and supporting a safe and healthy working life by combining wearable technologies, Big Data analytics, ergonomics, and information and communication technologies. The We@Work solution aims to support the worker and employer to ensure a healthy working life through pervasive monitoring for early warnings, prompt detection of capacity-loss and accurate risk assessments at workplace as well as self-management of a healthy working life. A multiservice platform will allow unobtrusive data collection at workplaces. Big Data analytics will provide real-time information useful to prevent work injuries and support healthy working life

  • 8.
    Adolfsson, Karin H.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lin, Chia-feng
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymer Technology.
    Hakkarainen, Minna
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Microwave Assisted Hydrothermal Carbonization and Solid State Postmodification of Carbonized Polypropylene2018In: ACS SUSTAINABLE CHEMISTRY & ENGINEERING, ISSN 2168-0485, Vol. 6, no 8, p. 11105-11114Article in journal (Refereed)
    Abstract [en]

    Functional carbon materials produced through a hydrothermal treatment of waste products have gained interest. Particularly, the method is considered more facile and green compared to conventional decomposition methods. Here, we demonstrated an upcycling of polypropylene (PP) waste to carbon materials by a microwave assisted hydro thermal treatment. The solid product obtained from the hydrothermal treatment was analyzed by multiple techniques to reveal the structure and the influence of processing conditions on PP degradation and hydrothermal carbonization. Chemical analyses showed the presence of carbonaceous material independent of acid amount (20 and 30 mL), temperature (210 and 250 degrees C), and time (20-80 min). A complete transformation of PP content to amorphous carbon required 60 min at 250 degrees C. The mass yield of the solid product decreased as a function of harsher processing conditions. At the same time, thermogravimetric analysis illustrated products with increasing thermal stability and a larger amount of remaining residue at 600 degrees C. The solid products consisted of irregular fragments and sheet-like structures. A solid state microwave process in air atmosphere was performed on a product with incomplete carbonization. The modification resulted in a decreased C/O ratio, and TGA analysis in nitrogen showed high thermal stability and degree of carbonization as indicated by the remaining residue of 86.4% at 600 degrees C. The new insights provided on the hydrothermal carbonization, and postmodification in air atmosphere, can catalyze effective handling of plastic waste by enabling transformation of low quality waste into functional carbon materials.

  • 9.
    Aguilera Costa, Joakim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Uppgradering och identifiering av cellulosa och hemicellulosa i restströmmar från jordbruk och skogsindustri2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    By-products are in focus for further processing. Residues from agriculture and forest industry contain a large amount of fiber, and this work investigates the qualitative properties of residues and whether there is potential for using them in the cellulose industry.

    By-products collected were wheat straw, rapeseed straw, wheat bran, betfor, silage, branches, primary sludge, sawdust and fiber rejects. A literature study was conducted around each by-product to get a better understanding of what they consist of and how they occur.

    By extracting holocellulose from the by-products, the qualitative properties of the fibers were analyzed. For the slightest change in the shape and dimensions of fibers, a maceration method was used to extract holocellulose from the by-products.

    Methods used to analyze the qualitative properties of the by-products were viscosity, titrations and gravimetric analyzes. With these methods, mass exchanges, ash levels, mass viscosities, peracetic acid and hydrogen peroxide levels could be determined for the extracted holocellulose masses.

    To investigate whether the extracted holocellulose masses can be used in the cellulosic industry, two types of processes were tested. One was aerogel production and the other a compression mold to produce high strength biocomposites.

    It was found that the fiber rejects yielded the greatest holocellulose exchange compared to the other residues. The analyzes gave the result that sawdust had the fibers with the highest degree of polymerization while wheat bran and betfor had the fibers with the lowest degree of polymerization. The dissociation of the holocellulose mass could not be performed because the test sample had either a too high mass viscosity or a too high a proportion of hemicellulose which prevents the solvent from dissolving the fibers. Compression molding of the holocellulose mass from wheat straw was successful as it was possible to make the soft pulp a lot more rigid. Compression molding of the holocellulose masses may be an alternative for producing additive manufacturing materials (3D printing).

  • 10.
    Ahlquist, Mårten S. G.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Marcos-Escartin, Rocio
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Theoretical Chemistry and Biology.
    Bicarbonate hydrogenation by iron: Effects of solvent and ligand on the mechanism2018In: Abstract of Papers of the American Chemical Society, ISSN 0065-7727, Vol. 255Article in journal (Other academic)
  • 11.
    Ahluwalia, A.
    et al.
    Italy.
    De Maria, C.
    Italy.
    Lantada, A. D.
    Spain.
    Pietro, L. D.
    Italy.
    Ravizza, A.
    Italy.
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Madete, J.
    Kenya.
    Makobore, P. N.
    Uganda.
    Aabloo, A.
    Estonia.
    Kitsing, R.
    Estonia.
    Leivobits, A.
    Estonia.
    Towards open source medical devices current situation, inspiring advances and challenges2018In: BIODEVICES 2018 - 11th International Conference on Biomedical Electronics and Devices, Proceedings; Part of 11th International Joint Conference on Biomedical Engineering Systems and Technologies, BIOSTEC 2018, SciTePress, 2018, p. 141-149Conference paper (Refereed)
    Abstract [en]

    Open Source Medical Devices may be part of the solution towards the democratization of medical technologies pursuing Universal Health Coverage as part of the Sustainable Development Goals for United Nations. Recent technological advances, especially in information and communication technologies, combined with innovative collaborative design methodologies and manufacturing techniques allow for the mass-personalization of biodevices and help to optimize the related development times and costs, while keeping safety in the foreground through the whole life cycle of medical products. These advantages can be further promoted by adequately fostering collaboration, communication, high value information exchange, and sustainable partnerships and by extending the employment of open source strategies. To this end, within the UBORA project, we are developing a framework for training the biomedical engineers of the future in open-source collaborative design strategies and for supporting the sharing of information and the assessment of safety and efficacy in novel biodevices. An essential part of this open-source collaborative framework is the UBORA e-infrastructure, which is presented in this study, together with some initial success cases. Main future challenges, connected with regulatory harmonization, with educational issues and with accessible and open design and manufacturing resources, among others, are also presented and discussed.

  • 12.
    Ahluwalia, Arti
    et al.
    Univ Pisa, Dept Ingn Informaz, Bioengn, Pisa, Italy..
    De Maria, Carmelo
    Univ Pisa, Dept Ingn Informaz, Bioengn, Pisa, Italy..
    Diaz Lantada, Andres
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Madete, June
    Univ Pisa, Res Ctr E Piaggio, Pisa, Italy.;Kenyatta Univ, Nairobi, Kenya..
    Makobore, Philippa Ngaju
    Uganda Ind Res Inst, Instrumentat Div, Kampala, Uganda..
    Ravizza, Alice
    Univ Pisa, Pisa, Italy..
    Di Pietro, Licia
    Mridha, Mannan
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Health Informatics and Logistics.
    Munoz-Guijosa, Juan Manuel
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Tanarro, Enrique Chacon
    UPM, ETSII, Dept Mech Engn, Madrid, Spain..
    Torop, Janno
    Tartu Ulikool, Inst Technol, Tartu, Estonia..
    Biomedical Engineering Project Based Learning: Euro-African Design School Focused on Medical Devices2018In: International Journal of Engineering ,Science and Innovative Technology, ISSN 0949-149X, E-ISSN 2277-3754, Vol. 34, no 5, p. 1709-1722Article in journal (Refereed)
    Abstract [en]

    Biomedical engineering (BME) has the potential of transforming medical care towards universal healthcare by means of the democratization of medical technology. To this end, innovative holistic approaches and multidisciplinary teams, built upon the gathering of international talent, should be encouraged within the medical industry. However, these transformations can only be accomplished if BME education also continuously evolves and focuses on the internationalization of students, the promotion of collaborative design strategies and the orientation towards context relevant medical needs. In this study we describe an international teaching-learning experience, the "UBORA (Swahili for 'excellence') Design School". During an intensive week of training and collaboration 39 engineering students lived through the complete development process for creating innovative open-source medical devices following the CDIO ("conceivedesign-implement-operate") approach and using the UBORA e-infrastructure as a co-design platform. Our post-school survey and analyses showed that this integral teaching-learning experience helped to promote professional skills and could nurture the future generation of biomedical engineers, who could transform healthcare technology through collaborative design oriented to open source medical devices.

  • 13.
    Ahmad, Shargeel
    et al.
    Dalian Univ Technol, Inst Artificial Photosynthesis, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Liu, Jinxuan
    Dalian Univ Technol, Inst Artificial Photosynthesis, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Ji, Wei
    Dalian Univ Technol, Inst Artificial Photosynthesis, State Key Lab Fine Chem, Dalian 116024, Peoples R China..
    Sun, Licheng
    KTH, School of Chemical Science and Engineering (CHE), Centres, Centre of Molecular Devices, CMD. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry. Dalian Univ Technol, Inst Artificial Photosynthesis, State Key Lab Fine Chem, Dalian 116024, Peoples R China.;KTH Royal Inst Technol, Sch Chem Sci & Engn, Dept Chem, S-10044 Stockholm, Sweden..
    Metal-Organic Framework Thin Film-Based Dye Sensitized Solar Cells with Enhanced Photocurrent2018In: Materials, ISSN 1996-1944, E-ISSN 1996-1944, Vol. 11, no 10, article id 1868Article in journal (Refereed)
    Abstract [en]

    Metal-organic framework thin film-based dye sensitized solar cell is fabricated with highly oriented, crystalline, and porous Zn-perylene metal-organic framework (MOF) thin film (SURMOF) which is integrated with Bodipy embedded in poly(methyl methacrylate). It has been demonstrated that the photocurrent can be enhanced by a factor of 5 relative to Zn-perylene MOF thin film due to triplet-triplet annihilation up-conversion between the Bodipy/PMMA sensitizer and the Zn-perylene MOF thin film acceptor using Co(bpy)(3)(2+/3+) as redox mediator.

  • 14.
    Akhter, Shirin
    et al.
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala Bioctr, Dept Plant Biol, Uppsala, Sweden..
    Kretzschmar, Warren W.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH Royal Inst Technol, Sch Engn Sci Biotechnol Chem & Hlth, Dept Gene Technol, Sci Life Lab, Solna, Sweden..
    Nordal, Veronika
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala Bioctr, Dept Plant Biol, Uppsala, Sweden..
    Delhomme, Nicolas
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Umea, Sweden..
    Street, Nathaniel R.
    Umea Sweden, Dept Plant Physiol, Umea Plant Sci Ctr, Umea, Sweden..
    Nilsson, Ove
    Swedish Univ Agr Sci, Dept Forest Genet & Plant Physiol, Umea Plant Sci Ctr, Umea, Sweden..
    Emanuelsson, Olof
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Sundström, Jens F.
    Swedish Univ Agr Sci, Linnean Ctr Plant Biol, Uppsala Bioctr, Dept Plant Biol, Uppsala, Sweden..
    Integrative Analysis of Three RNA Sequencing Methods Identifies Mutually Exclusive Exons of MADS-Box Isoforms During Early Bud Development in Picea abies2018In: Frontiers in Plant Science, ISSN 1664-462X, E-ISSN 1664-462X, Vol. 9, article id 1625Article in journal (Refereed)
    Abstract [en]

    Recent efforts to sequence the genomes and transcriptomes of several gymnosperm species have revealed an increased complexity in certain gene families in gymnosperms as compared to angiosperms. One example of this is the gymnosperm sister Glade to angiosperm TM3-like MADS-box genes, which at least in the conifer lineage has expanded in number of genes. We have previously identified a member of this subclade, the conifer gene DEFICIENS AGAMOUS LIKE 19 (DAL19), as being specifically upregulated in cone-setting shoots. Here, we show through Sanger sequencing of mRNA-derived cDNA and mapping to assembled conifer genomic sequences that DAL19 produces six mature mRNA splice variants in Picea abies. These splice variants use alternate first and last exons, while their four central exons constitute a core region present in all six transcripts. Thus, they are likely to be transcript isoforms. Quantitative Real-Time PCR revealed that two mutually exclusive first DAL19 exons are differentially expressed across meristems that will form either male or female cones, or vegetative shoots. Furthermore, mRNA in situ hybridization revealed that two mutually exclusive last DAL19 exons were expressed in a cell-specific pattern within bud meristems. Based on these findings in DAL19, we developed a sensitive approach to transcript isoform assembly from short-read sequencing of mRNA. We applied this method to 42 putative MADS-box core regions in P abies, from which we assembled 1084 putative transcripts. We manually curated these transcripts to arrive at 933 assembled transcript isoforms of 38 putative MADS-box genes. 152 of these isoforms, which we assign to 28 putative MADS-box genes, were differentially expressed across eight female, male, and vegetative buds. We further provide evidence of the expression of 16 out of the 38 putative MADS-box genes by mapping PacBio Iso-Seq circular consensus reads derived from pooled sample sequencing to assembled transcripts. In summary, our analyses reveal the use of mutually exclusive exons of MADS-box gene isoforms during early bud development in P. abies, and we find that the large number of identified MADS-box transcripts in P. abies results not only from expansion of the gene family through gene duplication events but also from the generation of numerous splice variants.

  • 15.
    Alander, B.
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Capezza, A.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials. Department of Plant Breeding, The Swedish University of Agricultural Sciences, Box 101, Alnarp, Sweden.
    Wu, Q.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Johansson, E.
    Olsson, Richard T.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Hedenqvist, Mikael
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    A facile way of making inexpensive rigid and soft protein biofoams with rapid liquid absorption2018In: Industrial crops and products (Print), ISSN 0926-6690, E-ISSN 1872-633X, Vol. 119, p. 41-48Article in journal (Refereed)
    Abstract [en]

    A novel and facile method to produce inexpensive protein biofoams suitable for sponge applications is presented. The protein used in the study was wheat gluten (WG), readily available as a by/co-product, but the method is expected to work for other cross-linkable proteins. The foams were obtained by high-speed stirring of pristine WG powder in water at room temperature followed by drying. Glutaraldehyde was used to crosslink the foam material in order to stabilize the dispersion, reduce its tackiness and improve the strength of the final foam. The foams were of medium to high density and absorbed readily both hydrophobic and hydrophilic liquids. The foam structure, consisting primarily of an open pore/channel system, led to a remarkably fast capillary-driven (pore-filling only) uptake of a hydrophobic liquid (limonene). Essentially all uptake occurred within the first second (to ca. 90% of the dry weight). In a polar liquid (water), the rapid pore-filling occurred in parallel with a more time-dependent swelling of the foam matrix material. Further improvement in the foam strength was achieved by making a denser foam or adding TEMPO-oxidized cellulose nanofibres. Soft foams were obtained by adding glycerol.

  • 16.
    Aldabbagh, Zina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    En undersökning av Rönningesjöns miljötillstånd, särskilt när det gäller metaller2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Lake Rönningesjön lies in a geological fault (a crack) and it is affected by the clay in the surrounding fields. The pH-values lie within the interval 7.1–7.7. The lake is also impacted by the roads around the lake. The incoming water contains large amounts of road salt. From the cars also large amounts of metal ions are transported by the incoming storm water. In this project copper, chromium and lead are measured. Most of the metals in the lake pass through the wetland at Löttingelund in one end of the lake and flows through the lake to the outlet, which delivers the metal ions into Hägernäsviken, which is a part of the Baltic Sea. However, a part of the metal ions are precipitated in the lake. The concentrations of metal ions in the lake water are too high. Metal ions are also stored in the sediments. Special dams should be constructed to remove particle bound metals from the storm water, by sedimentation.

  • 17.
    Alekseeva, L. A.
    et al.
    Natl Acad Sci Ukraine, B Verkin Inst Low Temp Phys & Engn, 47 Nauky Ave, UA-61103 Kharkov, Ukraine..
    Dobryden, Illia
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science.
    Determination of the low-temperature self-diffusion coefficient in solid p-H-2 from creep experiments2018In: Low temperature physics (Woodbury, N.Y., Print), ISSN 1063-777X, E-ISSN 1090-6517, Vol. 44, no 9, p. 946-951Article in journal (Refereed)
    Abstract [en]

    Dependencies of the relative elongation epsilon under the constantly applied stress at T = 1.8 K on the endurance time t of polycrystalline parahydrogen (p-H-2, similar to 0.2% of o-H-2) of high purity (99.9999 mol.%), with varying deuterium content, were measured. The region of linear dependence between the measured creep rates (epsilon) over dot of samples and the applied stress s was revealed. The conclusion that the low-temperature creep of the studied p-H-2 possesses a vacancy-type diffusion character was made on the basis of linear dependence (epsilon) over dot similar to s. Determination of the low-temperature self-diffusion coefficient of vacancies D in solid p-H-2, which characterizes the rate of low-temperature mass transfer, was performed. The cases of migration of vacancies in the crystal bulk, along boundaries separating individual crystallites, as well as between dislocations existing in crystals, are considered. A significant decrease in the (epsilon) over dot and D values with an increase in the isotope concentration in the samples was observed, while maintaining the linear relationship between (epsilon) over dot and s for the studied p-H-2. Published by AIP Publishing.

  • 18.
    Alemrajabi, Mahmood
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering, Transport Phenomena.
    Recovery of Rare Earth Elements from an Apatite Concentrate2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Rare earth elements (REE) are a group of 17 elements including lanthanides, yttrium and scandium; which are found in a variety of classes of minerals worldwide. The criticality of the application, lack of high grade and economically feasible REE resources and a monopolistic supply situation has raised significant attention in recovery of these metals from low grade ores and waste materials. In this thesis, the recovery of REE from an apatite concentrate, containing 0.5 mass% of REE, within the nitrophosphate route of fertilizer production has been investigated. Most of the REE (≥ 95%) content can be recovered into a phosphate precipitate with almost 30 mass% REE. Different processes have been developed to convert the REE phosphate precipitate into a more soluble form to obtain a solution suitable for further REE purification and individual separation. It has been shown that after reprecipitation of the REE phosphate concentrate as REE sodium double sulphate and then transformation into a REE hydroxide concentrate, a solution containing 45g/L REE free of Ca, Fe and P can be obtained. The results suggest that the apatite waste after processing of iron ore have the potential to be a very important source for REE in Europe and that the economy is strongly supported by the simultaneous extraction of phosphorous.

    The potential of using hollow fiber supported liquid membrane (HFSLM) extraction in individual and group separation of REE has been investigated. A hollow fiber supported liquid membrane plant in pilot scale has been operated according to the three main configurations: standard hollow fiber supported liquid membrane technology (HFSLM); hollow fiber renewal liquid membrane technology (HFRSLM) and emulsion pertraction technology (EPT). The standard HFSLM operation is more selective than HFRSLM and EPT, while higher metal transport rate is observed in EPT followed by HFRSLM and HFSLM. The HFRLM configuration helps to maintain the performance of the liquid membrane.

  • 19.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Dephosphorization and impurity removal from a rare earth phosphate concentrate2017Conference paper (Refereed)
  • 20.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke C.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Isolation of Rare Earth Element Phosphate Precipitates in the Nitrophosphate Process for Manufacturing of Fertilizer2016Conference paper (Refereed)
    Abstract [en]

    In the present study, the recovery of rare earth elements (REE) in the nitrophosphate process of fertilizer production is investigated. The apatite has been recovered from iron ore tailings by flotation. After digestion of apatite in concentrated nitric acid, Ca(NO3)2.4H2O is first separated by cooling crystallization and then the REEs are recovered by precipitation. Optimum conditions in these steps have been determined in a previous study. The precipitate mainly consists of CaHPO4.2H2O and REE phosphates. In the present study, selective dissolution and re-precipitation have been studied in order to obtain a precipitate that is more concentrated in REEs. The precipitate was selectively dissolved in nitric and phosphoric acid at different acidities (pH 6 to 0) with the liquid /solid ratio of 100 mL/g. It is shown that most of the CaHPO4.2H2O and other calcium containing compounds will be dissolved at pH 2 while the REE phosphates are not dissolved above a pH of approximately 2. Thus, by partial dissolution of the REE precipitate at pH 2.5 most of the solid calcium phosphates will be dissolved and the remaining solid phase, which is more concentrated in REEs, can be filtered off as a fairly concentrated REE solid mass and the liquor can be recycled back to recover more P nutrients. Alternatively, the REE enriched precipitate was dissolved completely in nitric acid and re-precipitated again by addition of ammonium hydroxide to pH 1.2. A chemical equilibrium software, MEDUSA (Puigdomenech, 2013) has been used to evaluate the experimental results and to estimate the optimum conditions for selectively dissolving the precipitate.

  • 21.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Recovery of phosphorous and rare earth elements from an apatite concentrate2018Conference paper (Refereed)
  • 22.
    Alemrajabi, Mahmood
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Korkmaz, Kivanc
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Upgrading of a rare earth phosphate concentrate within the nitrophosphate process2018In: Journal of Cleaner Production, ISSN 0959-6526, E-ISSN 1879-1786, Vol. 198, p. 551-563Article in journal (Refereed)
    Abstract [en]

    In the nitrophosphate process of fertilizer production, rare earth elements (REE) can be recovered as a REE phosphate concentrate. In this process, after digestion of apatite in concentrated nitric acid, Ca(NO3)2.4H2O is first separated by cooling crystallization and then the REE are precipitated in phosphate form by a partial neutralization step using ammonia. The obtained REE phosphate concentrate is contaminated by mainly calcium and iron, and the main solid phases are CaHPO4.2H2O, FePO4.2H2O and REEPO4.nH2O.

    In this study, a process to obtain a concentrate more enriched with REE with low concentration of calcium and iron and free of phosphorous is developed. In the developed process, enrichment and dephosphorization of the rare earth phosphate concentrate has been achieved by selective dissolution and re-precipitation of the REE as a sodium REE double sulfate salt. It is shown that by selective dissolution of the REE concentrate in nitric acid at a pH of 2.4, most of the calcium and phosphorus are dissolved, and a solid phase more enriched in REE is obtained. Thereafter, the REE phosphate concentrate is first dissolved in a mixture of sulfuric-phosphoric acid and then the REE are reprecipitated as NaREE(SO4)2.H2O by addition of a sodium salt. More than 95% of the Ca, Fe and P are removed and a REE concentrate containing almost 30 mass% total REE is obtained.

  • 23.
    Alemrajabi, Mahmoud
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Forsberg, Kerstin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Rasmuson, Åke
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemical Engineering.
    Recovery of REE from an apatite concentrate in the nitrophosphate process of fertilizer production.2015Conference paper (Refereed)
  • 24.
    Alexakis, Alexandros Efraim
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Preparation and Testing of FDCA based Nanocomposites2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    The project focuses on the use of diallyl 2,5-furanedicarboxylate (DAFDC) as a bio-based alternative for phthalic acid based thermosets. Initially, kinetic analysis, by means of Borchardt and Daniels method was performed to study the curing conditions. However, this model gave inaccurate results mainly due to different conditions apparent during Differential Scanning Calorimetry (DSC) measurement which were not able to be simulated in the experimental procedure that was followed. Nevertheless, by curing DAFDC with  of dicumyl peroxide (DCP), which comprise the matrix, and incorporating graphene oxide nanodots (GONDs) and carbon nanotubes (CNTs) in different weight amounts, in a staggered temperature and time fashion, nanocomposites based on DAFDC were produced. GONDs were oxidized from carbon nanospheres (CNs). The latter were produced from cellulose by adding a dialysis step in the protocol found in the literature 2.

    Through the characterization of the nanocomposites, it was concluded that the above protocol resulted in partially crosslinked materials which were further cured at elevated temperatures during Dynamical Mechanical Analysis (DMA). The fully crosslinked nanocomposites produced from this heating ramp exhibited enhanced properties. More specifically, the degradation temperature corresponding to  loss of mass, i.e. , seemed to be unaffected by the filler content and compared to the matrix it was enhanced by roughly  and  for GOND-filled and CNT-filled nanocomposites, respectively. Conductivity measurements gave an insight on the percolation threshold of the produced nanocomposites. On the one hand, CNT-filled nanocomposites exhibited a percolation threshold at  of CNT and their conductivity was increasing by increasing filler content. On the other hand, for GOND-filled nanocomposites, the filler content seemed to be lower than this threshold, since no electrical conductivity value could be monitored. The mechanical testing showed indications of enhanced properties of the fully cured nanocomposites compared to their partially cured analogues. However, due to the geometry and breaking of the cured samples during DMA, the mechanical properties could not be verified. Finally, the morphology of the nanocomposites was investigated by means of digital microscopy. Both sides of the samples were studied, since the side that was in contact with oxygen during curing, exhibited different morphological behavior than the side that was not in contact with oxygen. In particular, the side which was in contact with oxygen, showed a smoother surface than the side which was in contact with the mold.

    In conclusion, the possibility to produce a bio-based alternative of phthalic acid based thermosets was verified, giving the opportunity to eagerly investigate this monomer in different applications in the future.

  • 25.
    Ali pour, Nazanin
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Enebro, J.
    Strömberg, Emma
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Qualitative characterization of nanoclay particle emissions from PP nanocomposites after thermal degradation2015In: ICCM International Conferences on Composite Materials, International Committee on Composite Materials , 2015Conference paper (Refereed)
    Abstract [en]

    The use of nanomaterials in polymeric materials is a rapidly expanding field, and the polymer nanocomposites are being introduced into various markets. But there is still little known about the fate of nanocomposites and nanoparticles during service life and end-of-life of the materials. To avoid possible environmental, health and safety problems, simulating different scenarios for nanoparticles release from the polymer matrix plays a key role in commercialization of these advanced materials. The polymer/nanoclay nanocomposites show superior material properties in comparison with the pure polymers, such as improved mechanical properties, heat resistance, flame retardancy and decreased gas permeability. Polypropylene (PP) nanocomposites have attracted a considerable interest due to the material's low cost, low density and extensive production volumes. In this study, in order to obtain reliable results regarding the release of nanoclays from PP nanocomposites, homogenous composite with predetermined content of nanoclay was produced and characterized to obtain information regarding content, dispersion and size of the nanoclays in the matrix. The PP nanocomposite was degraded under controlled conditions and the surface morphology as well as oxidation of the material was characterized with scanning electron microscopy (SEM) and infrared spectroscopy during degradation. A prototype environmental chamber was designed in order to collect nano-sized particles in a controlled manner and subsequent characterization of the released or formed particles was performed with transmission electron microscopy (TEM) and the exposed nanocomposite was analysed with thermogravimetric analysis (TGA). 

  • 26.
    Aljure, Mauricio
    et al.
    KTH, School of Electrical Engineering and Computer Science (EECS).
    Becerra Garcia, Marley
    KTH, School of Electrical Engineering and Computer Science (EECS), Electromagnetic Engineering.
    Karlsson, Mattias E.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Polymeric Materials.
    Streamer Inception from Ultra-Sharp Needles in Mineral Oil Based Nanofluids2018In: Energies, ISSN 1996-1073, E-ISSN 1996-1073, Vol. 11, no 8, article id 2064Article in journal (Refereed)
    Abstract [en]

    Positive and negative streamer inception voltages from ultra-sharp needle tips (with tip radii below 0.5 m) are measured in TiO2, SiO2, Al2O3, ZnO and C-60 nanofluids. The experiments are performed at several concentrations of nanoparticles dispersed in mineral oil. It is found that nanoparticles influence positive and negative streamers in different ways. TiO2, SiO2 and Al2O3 nanoparticles increase the positive streamer inception voltage only, whilst ZnO and C-60 nanoparticles augment the streamer inception voltages in both polarities. Using these results, the main hypotheses explaining the improvement in the dielectric strength of the host oil due to the presence of nanoparticles are analyzed. It is found that the water adsorption hypothesis of nanoparticles is consistent with the increments in the reported positive streamer inception voltages. It is also shown that the hypothesis of nanoparticles reducing the electron velocity by hopping transport mechanisms fails to explain the results obtained for negative streamers. Finally, the hypothesis of nanoparticles attaching electrons according to their charging characteristics is found to be consistent with the results hereby presented on negative streamers.

  • 27.
    Almandoz-Gil, Leire
    et al.
    Uppsala Univ, Dept Publ Hlth & Caring Sci, Mol Geriatr, SE-75185 Uppsala, Sweden..
    Welander, Hedvig
    Uppsala Univ, Dept Publ Hlth & Caring Sci, Mol Geriatr, SE-75185 Uppsala, Sweden..
    Ihse, Elisabeth
    Uppsala Univ, Dept Publ Hlth & Caring Sci, Mol Geriatr, SE-75185 Uppsala, Sweden..
    Khoonsari, Payam Emami
    Uppsala Univ, Dept Med Sci, SE-75185 Uppsala, Sweden..
    Musunuri, Sravani
    Uppsala Univ, Dept Med Sci, SE-75185 Uppsala, Sweden..
    Lendel, Christofer
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry.
    Sigvardson, Jessica
    BioArctic AB, Warfvinges Vag 35, SE-11251 Stockholm, Sweden..
    Karlsson, Mikael
    Uppsala Univ, Dept Engn Sci, SE-75121 Uppsala, Sweden..
    Ingelsson, Martin
    Uppsala Univ, Dept Publ Hlth & Caring Sci, Mol Geriatr, SE-75185 Uppsala, Sweden..
    Kultima, Kim
    Uppsala Univ, Dept Med Sci, SE-75185 Uppsala, Sweden..
    Bergstrom, Joakim
    Uppsala Univ, Dept Publ Hlth & Caring Sci, Mol Geriatr, SE-75185 Uppsala, Sweden..
    Low molar excess of 4-oxo-2-nonenal and 4-hydroxy-2-nonenal promote oligomerization of alpha-synuclein through different pathways (vol 110, pg 421, 2017)2018In: Free Radical Biology & Medicine, ISSN 0891-5849, E-ISSN 1873-4596, Vol. 117, p. 258-258Article in journal (Refereed)
  • 28.
    Alneberg, Johannes
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Bioinformatic Methods in Metagenomics2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Microbial organisms are a vital part of our global ecosystem. Yet, our knowledge of them is still lacking. Direct sequencing of microbial communities, i.e. metagenomics, have enabled detailed studies of these microscopic organisms by inspection of their DNA sequences without the need to culture them. Furthermore, the development of modern high- throughput sequencing technologies have made this approach more powerful and cost-effective. Taken together, this has shifted the field of microbiology from previously being centered around microscopy and culturing studies, to largely consist of computational analyses of DNA sequences. One such computational analysis which is the main focus of this thesis, aims at reconstruction of the complete DNA sequence of an organism, i.e. its genome, directly from short metagenomic sequences.

    This thesis consists of an introduction to the subject followed by five papers. Paper I describes a large metagenomic data resource spanning the Baltic Sea microbial communities. This dataset is complemented with a web-interface allowing researchers to easily extract and visualize detailed information. Paper II introduces a bioinformatic method which is able to reconstruct genomes from metagenomic data. This method, which is termed CONCOCT, is applied on Baltic Sea metagenomics data in Paper III and Paper V. This enabled the reconstruction of a large number of genomes. Analysis of these genomes in Paper III led to the proposal of, and evidence for, a global brackish microbiome. Paper IV presents a comparison between genomes reconstructed from metagenomes with single-cell sequenced genomes. This further validated the technique presented in Paper II as it was found to produce larger and more complete genomes than single-cell sequencing.

  • 29.
    Alneberg, Johannes
    et al.
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology.
    Bennke, Christin
    Leibniz Institute for Baltic Sea Research, Warnemünde, Germany.
    Beier, Sara
    Leibniz Institute for Baltic Sea Research, Warnemünde, Germany.
    Pinhassi, Jarone
    Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden.
    Jürgens, Klaus
    Leibniz Institute for Baltic Sea Research, Warnemünde, Germany.
    Ekman, Martin
    Department of Ecology, Environment and Plant Sciences, Stockholm University Science for Life Laboratory, Solna, Sweden.
    Ininbergs, Karolina
    Department of Ecology, Environment and Plant Sciences, Stockholm University Science for Life Laboratory, Solna, Sweden.
    Labrenz, Matthias
    Leibniz Institute for Baltic Sea Research, Warnemünde, Germany.
    Andersson, Anders F.
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology.
    Recovering 2,032 Baltic Sea microbial genomes by optimized metagenomic binningManuscript (preprint) (Other academic)
    Abstract [en]

    Aquatic microorganism are key drivers of global biogeochemical cycles and form the basis of aquatic food webs. However, there is still much left to be learned about these organisms and their interaction within specific environments, such as the Baltic Sea. Crucial information for such an understanding can be found within the genome sequences of organisms within the microbial community.

    In this study, the previous set of Baltic Sea clusters, constructed by Hugert et al., is greatly expanded using a large set of metagenomic samples, spanning the environmental gradients of the Baltic Sea. In total, 124 samples were individually assembled and binned to obtain 2,032 Metagenome Assembled Genomes (MAGs), clustered into 353 prokaryotic and 14 eukaryotic species- level clusters. The prokaryotic genomes were widely distributed over the prokaryotic tree of life, representing 20 different phyla, while the eukaryotic genomes were mostly limited to the division of Chlorophyta. The large number of reconstructed genomes allowed us to identify key factors determining the quality of the genome reconstructions.

    The Baltic Sea is heavily influenced of human activities of which we might not see the full implications. The genomes reported within this study will greatly aid further studies in our strive for an understanding of the Baltic Sea microbial ecosystem.

  • 30.
    Alneberg, Johannes
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Karlsson, Christofer M. G.
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, EEMiS, Kalmar, Sweden..
    Divne, Anna-Maria
    Uppsala Univ, Dept Cell & Mol Biol, SciLifeLab, Uppsala, Sweden..
    Bergin, Claudia
    Uppsala Univ, Dept Cell & Mol Biol, SciLifeLab, Uppsala, Sweden..
    Homa, Felix
    Uppsala Univ, Dept Cell & Mol Biol, SciLifeLab, Uppsala, Sweden..
    Lindh, Markus V.
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, EEMiS, Kalmar, Sweden.;Lund Univ, Dept Biol, Lund, Sweden..
    Hugerth, Luisa
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Ettema, Thijs J. G.
    Uppsala Univ, Dept Cell & Mol Biol, SciLifeLab, Uppsala, Sweden..
    Bertilsson, Stefan
    Uppsala Univ, Dept Ecol & Genet, Sci Life Lab, Limnol, Uppsala, Sweden..
    Andersson, Anders F.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH Royal Inst Technol, Sch Engn Sci Chem Biotechnol & Hlth, Dept Gene Technol, Sci Life Lab, Stockholm, Sweden..
    Pinhassi, Jarone
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, EEMiS, Kalmar, Sweden..
    Genomes from uncultivated prokaryotes: a comparison of metagenome-assembled and single-amplified genomes2018In: Microbiome, ISSN 0026-2633, E-ISSN 2049-2618, Vol. 6, article id 173Article in journal (Refereed)
    Abstract [en]

    Background: Prokaryotes dominate the biosphere and regulate biogeochemical processes essential to all life. Yet, our knowledge about their biology is for the most part limited to the minority that has been successfully cultured. Molecular techniques now allow for obtaining genome sequences of uncultivated prokaryotic taxa, facilitating in-depth analyses that may ultimately improve our understanding of these key organisms. Results: We compared results from two culture-independent strategies for recovering bacterial genomes: single-amplified genomes and metagenome-assembled genomes. Single-amplified genomes were obtained from samples collected at an offshore station in the Baltic Sea Proper and compared to previously obtained metagenome-assembled genomes from a time series at the same station. Among 16 single-amplified genomes analyzed, seven were found to match metagenome-assembled genomes, affiliated with a diverse set of taxa. Notably, genome pairs between the two approaches were nearly identical (average 99.51% sequence identity; range 98.77-99.84%) across overlapping regions (30-80% of each genome). Within matching pairs, the single-amplified genomes were consistently smaller and less complete, whereas the genetic functional profiles were maintained. For the metagenome-assembled genomes, only on average 3.6% of the bases were estimated to be missing from the genomes due to wrongly binned contigs. Conclusions: The strong agreement between the single-amplified and metagenome-assembled genomes emphasizes that both methods generate accurate genome information from uncultivated bacteria. Importantly, this implies that the research questions and the available resources are allowed to determine the selection of genomics approach for microbiome studies.

  • 31.
    Alneberg, Johannes
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Karlsson, Christofer M.G.
    Centre for Ecology and Evolution in Microbial Model Systems, EEMiS, Linnaeus University, Barlastgatan 11, 391 82 Kalmar, Sweden.
    Divne, Anna-Maria
    Department of Cell and Molecular Biology, SciLifeLab, Uppsala University, Uppsala, Sweden .
    Bergin, Claudia
    Department of Cell and Molecular Biology, SciLifeLab, Uppsala University, Uppsala, Sweden .
    Homa, Felix
    Department of Cell and Molecular Biology, SciLifeLab, Uppsala University, Uppsala, Sweden .
    Lindh, Markus V.
    Centre for Ecology and Evolution in Microbial Model Systems, EEMiS, Linnaeus University, Barlastgatan 11, 391 82 Kalmar, Sweden.
    Hugerth, Luisa W.
    Karolinska Institutet, Science for Life Laboratory, Department of Molecular, Tumour and Cell Biology, Centre for Translational Microbiome Research, Solna, Sweden.
    Ettema, Thijs JG
    Department of Cell and Molecular Biology, SciLifeLab, Uppsala University, Uppsala, Sweden.
    Bertilsson, Stefan
    Department of Ecology and Genetics, Limnology and Science for Life Laboratory, Uppsala University, Uppsala, Sweden.
    Andersson, Anders F.
    KTH, Centres, Science for Life Laboratory, SciLifeLab. KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology.
    Pinhassi, Jarone
    Centre for Ecology and Evolution in Microbial Model Systems, EEMiS, Linnaeus University, Barlastgatan 11, 391 82 Kalmar, Sweden.
    Genomes from uncultivated prokaryotes: a comparison of metagenome-assembled and single-amplified genomesManuscript (preprint) (Other academic)
    Abstract [en]

    Background: Prokaryotes dominate the biosphere and regulate biogeochemical processes essential to all life. Yet, our knowledge about their biology is for the most part limited to the minority that has been successfully cultured. Molecular techniques now allow for obtaining genome sequences of uncultivated prokaryotic taxa, facilitating in-depth analyses that may ultimately improve our understanding of these key organisms.

    Results: We compared results from two culture-independent strategies for recovering bacterial genomes: single-amplified genomes and metagenome-assembled genomes. Single-amplified genomes were obtained from samples collected at an offshore station in the Baltic Sea Proper and compared to previously obtained metagenome-assembled genomes from a time series at the same station. Among 16 single-amplified genomes analyzed, seven were found to match metagenome-assembled genomes, affiliated with a diverse set of taxa. Notably, genome pairs between the two approaches were nearly identical (>98.7% identity) across overlapping regions (30-80% of each genome). Within matching pairs, the single-amplified genomes were consistently smaller and less complete, whereas the genetic functional profiles were maintained. For the metagenome-assembled genomes, only on average 3.6% of the bases were estimated to be missing from the genomes due to wrongly binned contigs; the metagenome assembly was found to cause incompleteness to a higher degree than the binning procedure.

    Conclusions: The strong agreement between the single-amplified and metagenome-assembled genomes emphasizes that both methods generate accurate genome information from uncultivated bacteria. Importantly, this implies that the research questions and the available resources are allowed to determine the selection of genomics approach for microbiome studies.

  • 32.
    Alneberg, Johannes
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Sundh, John
    Science for Life Laboratory, Department of Biochemistry and Biophysics, Stockholm University, Solna, Sweden.
    Bennke, Christin
    Leibniz Institute for Baltic Sea Research, Warnemünde, Germany.
    Beier, Sara
    Leibniz Institute for Baltic Sea Research, Warnemünde, Germany.
    Lundin, Daniel
    Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden.
    Hugerth, Luisa
    KTH Royal Institute of Technology, Science for Life Laboratory, School of Biotechnology, Stockholm, Sweden.
    Pinhassi, Jarone
    Centre for Ecology and Evolution in Microbial Model Systems, Linnaeus University, Kalmar, Sweden.
    Kisand, Veljo
    University of Tartu, Institute of Technology, Tartu, Estonia.
    Riemann, Lasse
    Section for Marine Biological Section, Department of Biology, University of Copenhagen, Helsingør, Denmark.
    Jürgens, Klaus
    Leibniz Institute for Baltic Sea Research, Warnemünde, Germany.
    Labrenz, Matthias
    Leibniz Institute for Baltic Sea Research, Warnemünde, Germany.
    Andersson, Anders F.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    BARM and BalticMicrobeDB, a reference metagenome and interface to meta-omic data for the Baltic SeaManuscript (preprint) (Other academic)
    Abstract [en]

    The Baltic Sea is one of the world’s largest brackish water bodies and is characterised by pronounced physicochemical gradients where microbes are the main biogeochemical catalysts. Meta-omic methods provide rich information on the composition of, and activities within microbial ecosystems, but are computationally heavy to perform. We here present the BAltic Sea Reference Metagenome (BARM), complete with annotated genes to facilitate further studies with much less computational effort. The assembly is constructed using 2.6 billion metagenomic reads from 81 water samples, spanning both spatial and temporal dimensions, and contains 6.8 million genes that have been annotated for function and taxonomy. The assembly is useful as a reference, facilitating taxonomic and functional annotation of additional samples by simply mapping their reads against the assembly. This capability is demonstrated by the successful mapping and annotation of 24 external samples. In addition, we present a public web interface, BalticMicrobeDB, for interactive exploratory analysis of the dataset.

  • 33.
    Alneberg, Johannes
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    Sundh, John
    Stockholm Univ, Sci Life Lab, Dept Biochem & Biophys, S-17165 Solna, Sweden..
    Bennke, Christin
    Leibniz Inst Balt Sea Res Warnemunde, D-18119 Rostock, Germany..
    Beier, Sara
    Leibniz Inst Balt Sea Res Warnemunde, D-18119 Rostock, Germany..
    Lundin, Daniel
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, S-39182 Kalmar, Sweden..
    Hugerth, Luisa W.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab. Karolinska Inst, Dept Mol Tumor & Cell Biol, Ctr Translat Microbiome Res, Sci Life Lab, S-17165 Solna, Sweden..
    Pinhassi, Jarone
    Linnaeus Univ, Ctr Ecol & Evolut Microbial Model Syst, S-39182 Kalmar, Sweden..
    Kisand, Veljo
    Univ Tartu, Inst Technol, EE-50411 Tartu, Estonia..
    Riemann, Lasse
    Univ Copenhagen, Sect Marine Biol Sect, Dept Biol, DK-3000 Helsingor, Denmark..
    Juergens, Klaus
    Leibniz Inst Balt Sea Res Warnemunde, D-18119 Rostock, Germany..
    Labrenz, Matthias
    Leibniz Inst Balt Sea Res Warnemunde, D-18119 Rostock, Germany..
    Andersson, Anders F.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Gene Technology. KTH, Centres, Science for Life Laboratory, SciLifeLab.
    BARM and BalticMicrobeDB, a reference metagenome and interface to meta-omic data for the Baltic Sea2018In: Scientific Data, E-ISSN 2052-4463, Vol. 5, article id 180146Article in journal (Refereed)
    Abstract [en]

    The Baltic Sea is one of the world's largest brackish water bodies and is characterised by pronounced physicochemical gradients where microbes are the main biogeochemical catalysts. Meta-omic methods provide rich information on the composition of, and activities within, microbial ecosystems, but are computationally heavy to perform. We here present the Baltic Sea Reference Metagenome (BARM), complete with annotated genes to facilitate further studies with much less computational effort. The assembly is constructed using 2.6 billion metagenomic reads from 81 water samples, spanning both spatial and temporal dimensions, and contains 6.8 million genes that have been annotated for function and taxonomy. The assembly is useful as a reference, facilitating taxonomic and functional annotation of additional samples by simply mapping their reads against the assembly. This capability is demonstrated by the successful mapping and annotation of 24 external samples. In addition, we present a public web interface, BalticMicrobeDB, for interactive exploratory analysis of the dataset.

  • 34.
    Alsaeede, Mustafa
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Test and Evaluation of a Novel Passive Tool Used For Blood Dilution in Hematology Analyzers2017Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Executive Summary

    The Complete Blood Count (CBC) is considered one of the most commonly performed screening tests in medical diagnostics. The CBC is performed using a hematological analyzer, which counts the numbers and types of different cells within the blood. However, due to the high concentration of cells in the blood samples to be counted, the dilution process is considered an essential factor for obtaining accurate counting results. Below is an investigation for an invention of a unique method and device for blood sample dilution in hematology analyzers. As mentioned, before starting an analysis a hematology cell counter device must dilute a precise defined volume of a whole blood sample with a diluent reagent (in this study 20ml of a blood sample is diluted with 4,5ml of diluent reagent). This dilution process must be accurate and repeatable with a high precision to produce the target dilution ratio (here 1:200). Exclusive to almost all hematology analyzers today, shear values (SV) are used to obtain highly precise volumes. These SV components are however very costly and add a higher complexity to the systems. This thesis was therefore aimed as an experimental evaluation for a novel passive dilution tool called shearing block (SB), which could possibly then replace the SV and be used in the coming Haematology Analyzer Devices manufactured by Boule Medical AB. The SB has the advantages of being low cost, having a simple mechanism, being much more flexible for integration with any microfluidic system and also eliminates the need for complex control systems or equipment, thereby lowering the need for calibration and maintenance. If a SB could replace the SV with an equally precise accuracy on the 20ml blood volume it would be highly beneficial.

     

    The set hypothesis was that the dilution process via the SB, will only be affected by blood viscosity. Through changing the blood’s viscosity, via changing the hematocrit concentration (HCT) and blood sample temperature, this study aimed to conclude if this gave a significant effect on the blood sample dilution via the SB. This was achieved through two performed experiments both including the same control group (CG) along with a test group (TG). All tests were performed using the same blood sample, the same reference measuring device (Medonic M32) and experimental setup. The experimental setup included the control group, CG, (N=30) consisting of 20µl blood samples aspirated through an electronic pipette in room temperature condition being mixed with 4,5ml of diluent reagent that had been automatically dispensed by the Medonic M32 instrument. The 20µl blood together with the 4,5ml diluent resulted in the targeted 1:200 dilution ratio. The test group, TG, (where N=30 for each respective group) was diluted through the SB through a fully automated process for the targeted 1:200 dilution. All diluted blood samples were then analyzed on the Medonic M32 for all hematology parameters and the hemoglobin (HGB) parameter was used as an indicator to quantify the blood volume in the TG runs as compared to the CG reference runs. Two test groups (TG) were analyzed: the first investigating the effect of the HCT and the second of the sample temperature on the blood volume (before dilution) in the SB. The HCT concentration levels were tested at 15%, 27%, 33% and 58% with samples and test run and kept at a constant 25°C. The second test group investigated the effect of 15°C, 25°C, 35°C and 39°C on a blood sample with a constant HCT of 33%.

    The main aim of this experimental study was to validate the SB simulation. However, the experiments results, showed that the diluted blood volume via SB was strongly influenced by changes in hematocrit concentration and that the unwanted additional blood volume, was increasing directly proportionally with hematocrit concentration.  On the other hand, there seemed to be no apparent change in the blood volume on the SB diluted samples for the various temperature differences between 15-35°C. To conclude, the experiments results were not consistent with predictions of SB simulation model and there are two reasons that could explain that. Firstly, in the simulation the blood was approximated with a homogeneous fluid with a given viscosity. The second reason is the mismatch between the dilution process via the SB and the simulation (the simulation started with an idealized initial status, whereas the SB channel was prefilled by blood). This means that the simulation excluded any effect that may occur as a convection effect during blood flow inside the channel and whilst encountering diluent reagent. These two reasons explain why the results of the simulation was not consistent with that of the experiments, regarding the unwanted blood volume. Therefore, a new simulation is required. Recommendations for future actions: undoubtedly there are several optimizations that may increase the accuracy of the proposed SB design such as; removing the diluent's reservoir for eliminating the effect of bubbles, changing the geometrical angles or use a smaller diameter for the inlets and outlets of the microchannels to reduce the convection and diffusion effect, (which in turn would reduce the unwanted blood volume). Therefore, determining the best SB's microchannel structure to perform the dilution process with minimum unwanted blood volume remains a near future next step follow-up project.

  • 35. Altai, M.
    et al.
    Liu, Hao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science.
    Ding, Haozhong
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science.
    Mitran, B.
    Edqvist, P. -H
    Tolmachev, V.
    Orlova, A.
    Gräslund, Torbjörn
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science.
    Affibody-derived drug conjugates: Potent cytotoxic molecules for treatment of HER2 over-expressing tumors2018In: Journal of Controlled Release, ISSN 0168-3659, E-ISSN 1873-4995, Vol. 288, p. 84-95Article in journal (Refereed)
    Abstract [en]

    Patients with HER2-positive tumors often suffer resistance to therapy, warranting development of novel treatment modalities. Affibody molecules are small affinity proteins which can be engineered to bind to desired targets. They have in recent years been found to allow precise targeting of cancer specific molecular signatures such as the HER2 receptor. In this study, we have investigated the potential of an affibody molecule targeting HER2, ZHER2:2891, conjugated with the cytotoxic maytansine derivate MC-DM1, for targeted cancer therapy. ZHER2:2891 was expressed as a monomer (ZHER2:2891), dimer ((ZHER2:2891)2) and dimer with an albumin binding domain (ABD) for half-life extension ((ZHER2:2891)2-ABD). All proteins had a unique C-terminal cysteine that could be used for efficient and site-specific conjugation with MC-DM1. The resulting affibody drug conjugates were potent cytotoxic molecules for human cells over-expressing HER2, with sub-nanomolar IC50-values similar to trastuzumab emtansine, and did not affect cells with low HER2 expression. A biodistribution study of a radiolabeled version of (ZHER2:2891)2-ABD-MC-DM1, showed that it was taken up by the tumor. The major site of off-target uptake was the kidneys and to some extent the liver. (ZHER2:2891)2-ABD-MC-DM1 was found to have a half-life in circulation of 14 h. The compound was tolerated well by mice at 8.5 mg/kg and was shown to extend survival of mice bearing HER2 over-expressing tumors. The findings in this study show that affibody molecules are a promising class of engineered affinity proteins to specifically deliver small molecular drugs to cancer cells and that such conjugates are potential candidates for clinical evaluation on HER2-overexpressing cancers. 

  • 36.
    Altai, M.
    et al.
    Immunology, Genetics and Pathology, Uppsala, SWEDEN, .
    Vorobyeva, A.
    Immunology, Genetics and Pathology, Uppsala, SWEDEN, .
    Westerlund, Kristina
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Protein Engineering.
    Mitran, B.
    Div Mol Imaging, Uppsala, Sweden..
    Orlova, A.
    Div Mol Imaging, Uppsala, Sweden..
    Eriksson Karlström, Amelie
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Protein Engineering.
    Tolmachev, V.
    Immunology, Genetics and Pathology, Uppsala, SWEDEN, .
    A novel method for conjugation of PNA to antibodies for radionuclide based pretargeting: proof of principal2018In: European Journal of Nuclear Medicine and Molecular Imaging, ISSN 1619-7070, E-ISSN 1619-7089, Vol. 45, p. S648-S648Article in journal (Other academic)
  • 37. Altai, Mohamed
    et al.
    Liu, Hao
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Protein Engineering.
    Ding, Haozhong
    Mitran, Bogdan
    Edqvist, Per-Henrik
    Tolmachev, Vladimir
    Orlova, Anna
    Gräslund, Torbjorn
    Affibody-derived Drug Conjugates: Potent Cytotoxic Drugs ForTreatment Of HER2 Over-Expressing TumorsManuscript (preprint) (Other academic)
  • 38.
    Alvarez, Victor S
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Kleiven, Svein
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems, Neuronic Engineering.
    Effect of pediatric growth on cervical spine kinematics and deformations in automotive crashes2018In: Journal of Biomechanics, ISSN 0021-9290, E-ISSN 1873-2380, Vol. 71, p. 76-83, article id S0021-9290(18)30075-7Article in journal (Refereed)
    Abstract [en]

    Finite element (FE) models are a powerful tool that can be used to understand injury mechanisms and develop better safety systems. This study aims to extend the understanding of pediatric spine biomechanics, where there is a paucity of studies available. A newly developed and continuously scalable FE model was validated and scaled to 1.5-, 3-, 6-, 10-, 14- and 18-year-old using a non-linear scaling technique, accounting for local topological changes. The oldest and youngest ages were also scaled using homogeneous geometric scaling. To study the effect of pediatric spinal growth on head kinematics and intervertebral disc strain, the models were exerted to 3.5 g acceleration pulse at the T1 vertebra to simulate frontal, rear and side impacts. It was shown that the head rotation increases with age, but is over predicted when geometrically scaling down from 18- to 1.5-year-old and under predicted when geometrically scaling up from 1.5- to 18-year-old. The strain in the disc, however, showed a clear decrease with age in side impact and for the upper cervical spine in rear impact, indicating a higher susceptibility for neck injury at younger ages. In the frontal impact, no clear age dependence could be seen, suggesting a large contribution from changed facet joint angles, and lower levels of strain, suggesting a lower risk of injury. The results also highlight the benefit of rearward facing children in a seat limiting head lateral motion.

  • 39.
    Aminzadeh, Selda
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Valorization of Kraft Lignin by Fractionation and Chemical Modifications for Different Applications2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Abstract

    Lignin is one of the most abundant biopolymers. Approximately 70 million tons of technical lignin is generated annually, but only little is used for products other than energy. The complexity of lignin hinders full utilization in high-value products and materials. In spite of the large recent progress of knowledge of lignin structure and biosynthesis, much is still not fully understood, including structural inhomogeneity. We made synthetic lignin at different pH’s and obtained structural differences that might explain the structural inhomogeneity of lignin.

    Technical lignins from the chemical pulping are available in large scale, but the processes result in alterations, such as oxidation and condensation. Therefore, to utilize technical lignin, modifications, such as fractionation and/or chemical modifications are necessary. Fractionation with ceramic membranes is one way to lower the polydispersity of lignin. The main advantage is their tolerance towards high temperature and harsh conditions. We demonstrated that low Mw lignin was extracted from industrially produced LignoBoost lignin aiming: i) to investigate the performance of the membrane over time; ii) to analyze the antioxidant properties of the low Mw lignin.

    Chemical modification can also improve the properties of lignin. By adding moieties, different properties can be obtained. Amination and methacrylation of kraft lignin were performed, as well as lignin-silica hybrid materials with potential for the adsorption were produced and investigated.

    Non-modified and methacrylated lignin were used to synthesize lignin-St-DVB porous microspheres to be utilized as a sorbent for organic pollutants. The possibility to substitute styrene with methacrylated lignin was evaluated, demonstrating that interaction between lignin and DVB, and porosity increased.

    Lignin has certain antibacterial properties. Un-modified and modified (aminated) lignin samples and sphere nanoparticles of lignin were tested for their effect against gram-positive and gram-negative bacteria’s and an injectable hydrogel was developed with encapsulated lignin for being used as an injectable gel for the open wounds. Results demonstrated promising antibacterial efficiency of lignins against gram-positive, more especially better inhibition with aminated lignins against gram-positive and negative bacterium.

     

     

    The full text will be freely available from 2019-11-22 11:08
  • 40.
    Aminzadeh, Selda
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Haghniaz, R.
    Ottenhall, A.
    Sevastyanova, Olena
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Lindström, E.
    Khademhosseini, A.
    Lignin based hydrogel for the antibacterial applicationManuscript (preprint) (Other academic)
  • 41.
    Amiri, Fatemeh
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Nouiser, Sara
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Optisk metod för glukosmätning: En studie för framtida icke-invasiva blodglukosmätningar2017Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Today there are currently living around 365 000 people with diabetes in Sweden. Measuring of blood sugar can be experienced as painful and difficult with blood glucose monitoring devices found in the market. Using lancets and test strip makes direct contact with blood which increases the risk of infection. To reduce these risks and difficulties a non-invasive method is required. This method can even provide an opportunity for healthy individuals to monitor their blood glucose and prevent the disease.This thesis presents the disease, sequelae and the problem around blood glucose monitoring. The work is based on an earlier study about optic measurement of glucose. By illumine a solution of saline and glucose, with infrared-light from a LED, absorption is carried out by the glucose. The amount of transmitted light is detected and processed by a photodetector which generates a current that is converted to a voltage and amplified. This report examines a modification of the circuit used in the previous study to establish a correlation between the glucose concentration and the output voltage by adding a transimpedance amplifier around the photodetector.The results corroborate that the modification with the transimpedance gives a better correlation between the measured output voltage and glucose concentration. The measurements were compiled and plotted to compare which circuit gave a better correlation between the measured output voltage and glucose concentration. The study showed that the modification with transimpedance amplifier gives a better correlation, though it is not enough for clinical use.

  • 42.
    Ammendrup, Katrin
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Framework for Wireless Acquisition of Surface EMG and Real-Time Control2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Muscle driven devices are controlled or powered with muscle activation. These devices open up the possibility of offering patients with limited muscle function to automatically control assistive devices - for instance exoskeletons - with input from their own muscles. This solution would help a number of patient groups suffering from common conditions, such as spinal cord injuries, stroke and cerebral palsy.

    To use muscle activation as input it is necessary to have a way to communicate with the mus- cles. Electromyography (EMG) is a technology used to gain information about muscle function and activation. It is performed by measuring and analyzing electrical signals conducted by the muscles during activation. Activation and activation level can be seen from analyzed EMG signal. EMG signals are frequently measured and analyzed afterwards, however, to use it as a controlling an assistive devices, real time analysis is necessary. In this thesis real time acquisi- tion and analysis of EMG was performed. The measured signal was used as an input to control a simple MATLAB computer game.

    The EMG of a muscle of the forearm, Brachioradialis, was measured with Myon Aktos sys- tem. The measured signal was written to a server as soon as the measurements were acquired. MATLAB was used to connect to the server and performing the signal analysis. The analysis was kept simple in order to limit delay.

    The result showed that it was possible to acquire real time signal with this method. The delay was negligible, both for the testing and for the game play.

    Showing that it is possible to play a game with muscle activation supports the idea of a motor that can be controlled automatically with muscle input. Future work should focus on understanding movement intent with respect to EMG and on analyzing multiple signals from different muscles at the same time.

  • 43.
    Andersson, Linn
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Enskilda brunnars vattenkvalitet samt förekommande vattenreningstekniker2018Independent thesis Basic level (professional degree), 10 credits / 15 HE creditsStudent thesis
  • 44.
    Andreasson, Jörgen
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Organizational preconditions and supportive resources for Swedish healthcare managers.: Factors that contribute to or counteract changes2018Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Swedish Healthcare managers’ organizational preconditions and supportive resources are important for their ability to work with planned change in a sustainable way. This thesis further investigates these factors together with an output measure, healthcare process quality (HPQ).

    The overall aim was to investigate how healthcare managers’ organizational preconditions and support contribute to or counteract managers’ work with planned change in order to implement process development in a sustainable way. Specific aims were: to improve knowledge of managers’ views of and approaches to increasing their employees’ influence on and engagement in models for improving care processes (study I); to investigate relationships among managers’ organizational preconditions, support, and work to improve quality of care and HPQ over time (study II); to investigate whether managers’ coaching style, preconditions, implementation strategy, appraisal of change, and clinical autonomy are associated with HPQ (study III ); and to assess the influence of support from superiors, colleagues, external sources, subordinates, and private life on managers’ own health (study IV ).

    The data for Studies I – III came from five hospitals collected over a three-year period. The data were collected by means of interviews (Study I, qualitative analysis) and annual questionnaires (Studies II and III, quantitative and mixed-method analyses). The data for Study IV were based on questionnaires administered to first- and second-line managers in municipal care, twice during a two-year period.

    The results revealed that the healthcare managers were key actors in implementing planned change, but were dependent on their employees’ engagement in order to succeed. Managers’ appraisal of work with planned change became more positive with strong support from other managers, employees, and the organization as well as with long managerial experience. Support from private life and networks, as well as the managers’ attitudes towards their managerial role, predicted their own health. For new managers or managers with many employees, organizational support predicted their health-related sustainability. Managers practising a more distanced style of coaching (e.g., clearly delegating responsibility for implementation work to employees) were associated with better HPQ outcomes than were managers who were more involved in implementation. In conclusion, implementation of planned change are facilitated by, engaged managers, employees with knowledge of implementation work and of the healthcare system, as well as organizational structures that support the managers. Strong support from various sources as well as managerial experience are important for managers’ appraisal of work with planned change. Strong managerial support and a more delegated leadership style are both important factors related to higher estimated HPQ.

  • 45.
    Andreasson, Jörgen
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH).
    Ljungar, Erik
    Ahlstrom, Linda
    Hermansson, Jonas
    Dellve, Lotta
    Professional Bureaucracy and Health Care Managers’Planned Change Strategies: Governance in SwedishHealth Care2018In: Nordic Journal of Working Life Studies, ISSN 2245-0157, E-ISSN 2245-0157, Vol. 8, no 1, p. 23-41Article in journal (Refereed)
    Abstract [en]

    To increase efficiency and quality, process development has been implemented in many Swedish

    hospitals. These hospitals are usually organized as professional bureaucracies in which

    health care managers have limited decision control. The new governance principles has been

    implemented without removing bureaucratic elements. This study analyzes how managers implement

    planned change in these professional bureaucracies, considering if managers coaching

    style, organizational preconditions, implementation strategy, appraisal of change and clinic autonomy,

    is associated with health care process quality (HPQ). The study is based on interviews

    with health care managers and longitudinal assessments of HPQ. The results revealed significant

    differences between coaching style, organizational preconditions, and HPQ over time. The

    conclusion is that leadership and preconditions is of importance for the health care manager’s

    ability to work with planned change, as that the health care managers understand how management

    methods, governance principles, and professional bureaucracies work in practice.

  • 46.
    Anette, Kniberg
    et al.
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    Nokto, David
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Biomedical Engineering and Health Systems.
    A Benchmark of Prevalent Feature Selection Algorithms on a Diverse Set of Classification Problems2018Independent thesis Advanced level (degree of Master (Two Years)), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Feature selection is the process of automatically selecting important features from data. It is an essential part of machine learning, artificial intelligence, data mining, and modelling in general. There are many feature selection algorithms available and the appropriate choice can be difficult. The aim of this thesis was to compare feature selection algorithms in order to provide an experimental basis for which algorithm to choose. The first phase involved assessing which algorithms are most common in the scientific community, through a systematic literature study in the two largest reference databases: Scopus and Web of Science. The second phase involved constructing and implementing a benchmark pipeline to compare 31 algorithms’ performance on 50 data sets.The selected features were used to construct classification models and their predictive performances were compared, as well as the runtime of the selection process. The results show a small overall superiority of embedded type algorithms, especially types that involve Decision Trees. However, there is no algorithm that is significantly superior in every case. The pipeline and data from the experiments can be used by practitioners in determining which algorithms to apply to their respective problems.

  • 47. Angiolini, L.
    et al.
    Valetti, S.
    Cohen, B.
    Feiler, Adam
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Chemistry, Surface and Corrosion Science. Nanologica AB, Södertälje, Sweden.
    Douhal, A.
    Fluorescence imaging of antibiotic clofazimine encapsulated within mesoporous silica particle carriers: Relevance to drug delivery and the effect on its release kinetics2018In: Physical Chemistry, Chemical Physics - PCCP, ISSN 1463-9076, E-ISSN 1463-9084, Vol. 20, no 17, p. 11899-11911Article in journal (Refereed)
    Abstract [en]

    We report on the encapsulation of the antibiotic clofazimine (CLZ) within the pores of mesoporous silica particles having hydrophilic (CBET value of 137) and more hydrophobic (CBET value of 94 after calcination at 600 °C) surfaces. We studied the effect of pH on the released amount of CLZ in aqueous solutions and observed a maximum at pH 4.1 in correlation with the solubility of the drug. Less release of the drug was observed from the more hydrophobic particles which was attributed to a difference in the affinity of the drug to the carrier particles. Fluorescence lifetime imaging microscopy, emission spectra, and fluorescence lifetimes of single drug loaded particles provided detailed understanding and new knowledge of the physical form of the encapsulated drug and the distribution within the particles. The distribution of CLZ within the particles was independent of the surface chemistry of the particles. The confirmation of CLZ molecules as monomers or aggregates was revealed by controlled removal of the drug with solvent. Additionally, the observed optical "halo effect" in the fluorescent images was interpreted in terms of specific quenching of high concentration of molecules. The emission lifetime experiments suggest stronger interaction of CLZ with the more hydrophobic particles, which is relevant to its release. The results reported in this work demonstrate that tuning the hydrophilicity/hydrophobicity of mesoporous silica particles can be used as a tool to control the release without impacting their loading ability.

  • 48.
    Annelies, Nonneman
    et al.
    KU Leuven Univ Leuven, Dept Neurosci, Lab Neurobiol & Expt Neurol, Herestr 49, B-3000 Leuven, Belgium.;LBI, Herestr 49, B-3000 Leuven, Belgium.;Ctr Brain & Dis Res, VIB, Herestr 49, B-3000 Leuven, Belgium..
    Nathan, Criem
    Ctr Brain & Dis Res, VIB, Herestr 49, B-3000 Leuven, Belgium.;KU Leuven Univ Leuven, Dept Cardiovasc Sci, Ctr Mol & Vasc Biol, Herestr 49, B-3000 Leuven, Belgium.;KU Leuven Univ Leuven, Dept Human Genet, Herestr 49, B-3000 Leuven, Belgium..
    Lewandowski, Sebastian
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Protein Science, Affinity Proteomics. KTH, Centres, Science for Life Laboratory, SciLifeLab. Karolinska Inst, Dept Clin Neurosci, S-17177 Stockholm, Sweden..
    Rik, Nuyts
    KU Leuven Univ Leuven, Dept Neurosci, Lab Neurobiol & Expt Neurol, Herestr 49, B-3000 Leuven, Belgium.;LBI, Herestr 49, B-3000 Leuven, Belgium.;Ctr Brain & Dis Res, VIB, Herestr 49, B-3000 Leuven, Belgium..
    Dietmar, Thal R.
    KU Leuven Univ Leuven, Dept Neurosci, Lab Neuropathol, Herestr 49, B-3000 Leuven, Belgium.;Univ Hosp Leuven, Dept Neurol, Herestr 49, B-3000 Leuven, Belgium..
    Frank, Pfrieger W.
    Univ Strasbourg, CNRS UPR 3212, Inst Cellular & Integrat Neurosci, F-67084 Strasbourg, France..
    John, Ravits
    Univ Calif San Diego, Dept Neurosci, 9500 Gilman Dr, San Diego, CA 92093 USA..
    Philip, Van Damme
    KU Leuven Univ Leuven, Dept Neurosci, Lab Neurobiol & Expt Neurol, Herestr 49, B-3000 Leuven, Belgium.;LBI, Herestr 49, B-3000 Leuven, Belgium.;Ctr Brain & Dis Res, VIB, Herestr 49, B-3000 Leuven, Belgium.;Univ Hosp Leuven, Dept Neurol, Herestr 49, B-3000 Leuven, Belgium..
    An, Zwijsen
    Ctr Brain & Dis Res, VIB, Herestr 49, B-3000 Leuven, Belgium.;KU Leuven Univ Leuven, Dept Cardiovasc Sci, Ctr Mol & Vasc Biol, Herestr 49, B-3000 Leuven, Belgium.;KU Leuven Univ Leuven, Dept Human Genet, Herestr 49, B-3000 Leuven, Belgium..
    Ludo, Van Den Bosch
    KU Leuven Univ Leuven, Dept Neurosci, Lab Neurobiol & Expt Neurol, Herestr 49, B-3000 Leuven, Belgium.;LBI, Herestr 49, B-3000 Leuven, Belgium.;Ctr Brain & Dis Res, VIB, Herestr 49, B-3000 Leuven, Belgium..
    Wim, Robberecht
    KU Leuven Univ Leuven, Dept Neurosci, Lab Neurobiol & Expt Neurol, Herestr 49, B-3000 Leuven, Belgium.;LBI, Herestr 49, B-3000 Leuven, Belgium.;Ctr Brain & Dis Res, VIB, Herestr 49, B-3000 Leuven, Belgium.;Univ Hosp Leuven, Dept Neurol, Herestr 49, B-3000 Leuven, Belgium..
    Astrocyte-derived Jagged-1 mitigates deleterious Notch signaling in amyotrophic lateral sclerosis2018In: Neurobiology of Disease, ISSN 0969-9961, E-ISSN 1095-953X, Vol. 119, p. 26-40Article in journal (Refereed)
    Abstract [en]

    Amyotrophic lateral sclerosis (ALS) is a late-onset devastating degenerative disease mainly affecting motor neurons. Motor neuron degeneration is accompanied and aggravated by oligodendroglial pathology and the presence of reactive astrocytes and microglia. We studied the role of the Notch signaling pathway in ALS, as it is implicated in several processes that may contribute to this disease, including axonal retraction, microgliosis, astrocytosis, oligodendrocyte precursor cell proliferation and differentiation, and cell death. We observed abnormal activation of the Notch signaling pathway in the spinal cord of SOD1(G93A) mice, a well-established model for ALS, as well as in the spinal cord of patients with sporadic ALS (sALS). This increased activation was particularly evident in reactive GFAP-positive astrocytes. In addition, one of the main Notch ligands, Jagged-1, was ectopically expressed in reactive astrocytes in spinal cord from ALS mice and patients, but absent in resting astrocytes. Astrocyte-specific inactivation of Jagged-1 in presymptomatic SOD1(G93A) mice further exacerbated the activation of the Notch signaling pathway and aggravated the course of the disease in these animals without affecting disease onset. These data suggest that aberrant Notch signaling activation contributes to the pathogenesis of ALS, both in sALS patients and SOD1(G93A) mice, and that it is mitigated in part by the upregulation of astrocytic Jagged-1.

  • 49.
    Ansari, Farhan
    et al.
    Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA..
    Ding, Yichuan
    Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA..
    Berglund, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology.
    Dauskardt, Reinhold H.
    Stanford Univ, Dept Mat Sci & Engn, Stanford, CA 94305 USA..
    Toward Sustainable Multifunctional Coatings Containing Nanocellulose in a Hybrid Glass Matrix2018In: ACS Nano, ISSN 1936-0851, E-ISSN 1936-086X, Vol. 12, no 6, p. 5495-5503Article in journal (Refereed)
    Abstract [en]

    We report on a sustainable route to protective nanocomposite coatings, where one of the components, nanocellulose fibrils, is derived from trees and the glass matrix is an inexpensive sol-gel organic-inorganic hybrid of zirconium alkoxide and an epoxy-functionalized silane. The hydrophilic nature of the colloidal nanocellulose fibrils is exploited to obtain a homogeneous one-pot suspension of the nanocellulose in the aqueous sol-gel matrix precursors solution. The mixture is then sprayed to form nano composite coatings of a well-dispersed, random in-plane nano cellulose fibril network in a continuous organic inorganic glass matrix phase. The nanocellulose incorporation in the sol-gel matrix resulted in nanostructured composites with marked effects on salient coating properties including optical transmittance, hardness, fracture energy, and water contact angle. The particular role of the nanocellulose fibrils on coating fracture properties, important for coating reliability, was analyzed and discussed in terms of fibril morphology, molecular matrix, and nanocellulose/matrix interactions.

  • 50.
    Ansari, Farhan
    et al.
    KTH, School of Engineering Sciences (SCI), Centres, VinnExcellence Center BiMaC Innovation.
    Galland, Sylvain
    Fernberg, P.
    Berglund, Lars
    KTH, School of Engineering Sciences in Chemistry, Biotechnology and Health (CBH), Fibre- and Polymer Technology, Biocomposites.
    Stiff and ductile nanocomposites of epoxy reinforced with cellulose nanofibrils2013In: ICCM International Conferences on Composite Materials, International Committee on Composite Materials , 2013, p. 5575-5582Conference paper (Refereed)
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