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  • 1.
    Carlsson, Tobias
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Kamerlin, Natasha
    Arteca, Gustavo A.
    Elvingson, Christer
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology. Uppsala University, Disciplinary Domain of Science and Technology, Chemistry, Department of Chemistry - Ångström, Physical Chemistry.
    Structure and compression dynamics of two mutually approaching polymer brushesManuscript (preprint) (Other academic)
  • 2.
    Chai, Qian
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Singh, Bhupender
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Peisker, Kristin
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Dasgupta, Santanu
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Sanyal, Suparna
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Distribution of ribosomes in action and at rest in Escherichia coli: involvement of bacterial cytoskeletonManuscript (preprint) (Other academic)
  • 3.
    Eriksson, Jenny
    et al.
    Högskolan Dalarna, Materialvetenskap.
    Olsson, Mikael
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Ranking the performance of lubricants, tool steels and PVD coatings for the forming of high strength steel using pin-on-disc testing2009In: Tool09: Tool steels, june 2nd-4th 2009 in aachen, germany, 2009Conference paper (Other academic)
    Abstract [en]

    The increasing use of high strength steels in a variety of mechanical engineering applications has illuminated problems associated with galling in sheet metal forming operations. Galling is a tribological phenomenon associated with transfer of material from the steel sheet to the tool surface during forming resulting in seizure of the tool/steel sheet contact and extensive scratching of the steel sheet surface. As a result, a number of concepts have been developed in order to reduce the tendency to galling in sheet metal forming, including the development of new dry lubricants, new forming tool steel grades and improved surface engineering treatments such as the deposition of low friction CVD- and PVD-coatings. In the present study the potential performance of these concepts in the forming of hot and cold rolled high strength steel as well as electro and hot-dip galvanized high strength steel has been evaluated using pin-on disc testing. In the tests, two different lubricants, a dry lubricant and a pre-lube oil, two different cold work tool steels, a conventional steel grade and a nitrogen alloyed PM steel grade, and two different PVD coatings, (Ti,Al)n and CrC/C, were evaluated. Post-test examination of the tribosurfaces using FEG-SEM, EDX and 3D surface profilometry was performed in order to evaluate the mechanisms controlling the material transfer and wear. In summary, the results show that the laboratory testing combined with post-test microscopy and surface analysis give valuable information in order to rank the galling resistance of lubricants, tool steels and PVD-coatings.

  • 4.
    Fjodorov, Anton
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Automation of a long-term measurement of organic solar cells2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    Organic solar cells represent a clean and renewable source of energy. They are cheaper and handier than conventional silicon solar cells, but have lower efficiency and shorter lifetime. This project was conducted to assist a two years' outdoor study on the lifetime of organic solarcells, in order to better understand the lifetime-affecting factors. An outdoor stand for the solar cells was designed, a partly working Python program for automatic measurement control was made and a stable link between all hardware parts in the setup was established.

  • 5.
    Forsgren, Johan
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Pedersen, Christian
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Maria, Strømme
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Nanotechnology and Functional Materials.
    Engqvist, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Adjustable nanostructure of synthetic geopolymers enables tunable and sustained release of oxycodoneArticle in journal (Refereed)
  • 6. Gellein, Kristin
    et al.
    Roos, Per M.
    Evje, Lars
    Vesterberg, Olof
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Flaten, Trond Peder
    Nordberg, Monica
    Syversen, Tore
    Separation of proteins including metallothionein in cerebrospinal fluid by size exclusion HPLC and determination of trace elements by HR-ICP-MS2007In: Brain Research, ISSN 0006-8993, E-ISSN 1872-6240, Vol. 1174, p. 136-142Article in journal (Refereed)
    Abstract [en]

    A method to study the protein binding patterns of trace elements in human cerebrospinal fluid (CSF) is described. Proteins in CSF samples were separated by size exclusion chromatography combined with high performance liquid chromatography (SEC-HPLC). The column was calibrated to separate proteins in the molecular weight range 6-70 kDa. Fractions were then analyzed off-line for trace elements using high resolution inductively coupled plasma mass spectrometry (HR-ICP-MS). We were able to accurately determine more than 10 elements of clinical interest in the CSF fractions. Results are presented for Cd, Mn, Fe, Pb, Cu and Zn. The total concentrations of 16 trace elements in human plasma and CSF are also presented. The method was able to differentiate the relative contribution of metallothionein and other proteins towards metal binding in human CSF.

  • 7.
    Ghosh, Jaydip
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Larsson, Pontus
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Singh, Bhupender
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Pettersson, B. M. Fredrik
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Islam, Nurul M.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Sarkar, Sailendra Nath
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Dasgupta, Santanu
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Kirsebom, Leif A.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Sporulation in mycobacteria2009In: Proceedings of the National Academy of Sciences of the United States of America, ISSN 0027-8424, E-ISSN 1091-6490, Vol. 106, no 26, p. 10781-10786Article in journal (Refereed)
  • 8.
    Gustafsson, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Lågtempererade uppvärmningssystem och dess potential i nybyggda och energieffektiva kontorshus: En studie i att använda returtemperatur från befintlig bebyggelse till uppvärmning2018Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This master thesis examine how a low temperature radiator systemcan be implemented in a new built office and what effects this will have on the return temperature. One point in the system was logged and data was collected. A model was then developed in VIP-Energy to determine the heating demand for an office building which were compared to the supply. A cost analysis was also performed on different types of low temperature radiator systems. These were compared to a conventional radiator system with a supply temperature of 55°C and a return temperature of 45°C. A cost analysis was also done on whether to build energy efficient or not. The study shows a strong correlation between the heat demand and the time of day. The demand is low during office hours and high during nights and weekends with a peak demand of 70 kW. The low demand is due to the high amount of process energy an office uses. The point in the system can supply the heat demand during almost every hour of the year. For the few hours where there is a mismatch between supplied heat and demand, a shunt solution can supply the return water with primary heat. If the heat demand is scaled up with ten or twenty identical houses the point will be unable to supply enough power to cover the heat demand for more hours a year. The most cost-effective radiator system is Purmo Belize with a supply temperature of 40°C and a return temperature of 30°C. Purmo Belize has built in fans that can improve the heat supply to the room with up to 80 %. Compared to a conventional radiator the payback time is 9 years, with a return on investment of 12,8 percent and a net present value of 151 762 kr. A 40/30°C-system will lower the return temperature in the measured point with 0,4°C. For the whole system this means a reduced temperature of 0,00003°C if the total flow is 50 m3/s and the average return temperature is 50°C. From a strictly economic point of view, an extra energy efficient house will be beneficial if the extra cost is up to 5 000 000 kr or around 700 kr/m2 with a depreciation time of 25 years.

  • 9.
    Karlsson, Christoffer
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Olsson, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Strømme, Maria
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Sjödin, Martin
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Isoindole-4,7-dione Polymers As Candidates For Organic Lithium Ion Battery Cathodes2012Conference paper (Refereed)
  • 10. Kren, F.
    et al.
    Bashkanov, M.
    Bogoslawsky, D.
    Calén, Hans
    Uppsala University, The Svedberg Laboratory. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Clement, H.
    Demiroers, L.
    Ekström, Curt
    Uppsala University, The Svedberg Laboratory.
    Fransson, K.
    Uppsala University, The Svedberg Laboratory.
    Greiff, J.
    Uppsala University, The Svedberg Laboratory.
    Gustafsson, L.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Höistad, Bo
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Ivanov, G.
    Jacewicz, Marek
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Jiganov, E.
    Johansson, Tord
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Khakimova, O.
    Keleta, S.
    Uppsala University.
    Koch, I.
    Uppsala University.
    Kullander, Sven
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, High Energy Physics.
    Kupsc, Andrzej
    Uppsala University, The Svedberg Laboratory. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Marciniewski, Pawel
    Uppsala University, The Svedberg Laboratory. Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Meier, R.
    Morosov, B.
    Pauly, C.
    Petrén, Henrik
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Applied Nuclear Physics.
    Petukhov, Y.
    Povtorejko, A.
    Ruber, R. J. M. Y.
    Uppsala University, The Svedberg Laboratory.
    Schönning, Karin
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Scobel, W.
    Skorodko, T.
    Shwartz, B.
    Stepaniak, J.
    Thörngren-Engblom, P.
    Uppsala University.
    Tikhomirov, V.
    Wagner, G. J.
    Wolke, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Yamamoto, A.
    Zabierowski, J.
    Zlomanczuk, Jozef
    Uppsala University, Disciplinary Domain of Science and Technology, Physics, Department of Physics and Astronomy, Nuclear Physics.
    Exclusive measurements of pp -> d pi(+)pi(0): Double-pionic fusion without ABC effect2010In: Physics Letters B, ISSN 0370-2693, E-ISSN 1873-2445, Vol. 684, no 2-3, p. 110-113Article in journal (Refereed)
    Abstract [en]

    Exclusive measurements of the reaction pp -> d pi(+)pi(0) have been carried out at T-p = 1.1 GeV at the CELSIUS storage ring using the WASA detector. The isovector pi(+)pi(0) channel exhibits no enhancement at low invariant pi pi masses, i.e. no ABC effect. Therefore this most basic isovector double-pionic fusion reaction qualifies as an ideal test case for the conventional t-channel Delta Delta excitation process. Indeed, the obtained differential distributions reveal the conventional t-channel Delta Delta mechanism as the appropriate reaction process, which also accounts for the observed energy dependence of the total cross section.

  • 11.
    Lundstedt, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Implementation and Evaluation of Image Retrieval Method Utilizing Geographic Location Metadata2009Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    Multimedia retrieval systems are very important today with millions of content creators all over the world generating huge multimedia archives. Recent developments allows for content based image and video retrieval. These methods are often quite slow, especially if applied on a library of millions of media items.

    In this research a novel image retrieval method is proposed, which utilizes spatial metadata on images. By finding clusters of images based on their geographic location, the spatial metadata, and combining this information with existing content- based image retrieval algorithms, the proposed method enables efficient presentation of high quality image retrieval results to system users.

    Clustering methods considered include Vector Quantization, Vector Quantization LBG and DBSCAN. Clustering was performed on three different similarity measures; spatial metadata, histogram similarity or texture similarity.

    For histogram similarity there are many different distance metrics to use when comparing histograms. Euclidean, Quadratic Form and Earth Mover’s Distance was studied. As well as three different color spaces; RGB, HSV and CIE Lab. 

  • 12.
    Ly, Jimmy
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Low noise electrical measurement setup for graphene and molecules in a gas atmosphere2011Independent thesis Basic level (degree of Bachelor), 15 credits / 22,5 HE creditsStudent thesis
  • 13.
    Ly, Sandra
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Sundin, Helena
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Thell, Linda
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Electric cars: The climate impact of electric cars, focusing on carbon dioxide equivalent emissions2012Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    This bachelor thesis examines and models the emissions of carbon dioxide equivalents of the composition of automobiles in Sweden 2012. The report will be based on three scenarios of electricity valuation principles, which are a snapshot perspective, a retrospective perspective and a future perspective. The snapshot perspective includes high and low values for electricity on the margin, the retrospective perspective includes Nordic and European electricity mix and the future perspective includes electricity on the margin for modest and high climate goals at 2030. The study is applied to an upcoming climate smart district, Brunnshög in Lund, and the goal is to determine the amount of emissions of carbon dioxide equivalents for the mentioned alternatives.

    The environmental effects depends largely on the fuel consumption for the compared types of cars and what electricity valuation principle that is used. The car fleet of 2012 generated 10 300 tonnes of carbon dioxide emissions. The future car fleet generated 400 tonnes of emissions for Nordic electricity mix, 3 200 tonnes for European electricity mix, 3 100 tonnes for electricity on the margin with low values, 5 800 tonnes for electricity on the margin with high values, 1 200 tonnes for electricity on the margin at 2030 for high climate goals and 4 600 tonnes for electricity on the margin at 2030 for modest climate goals.

    The emissions of carbon dioxide equivalents are at least halved in Brunnshög if 100 % electric cars are used instead of the composition of petrol, diesel and ethanol cars that are primarily used in Sweden 2012. Hence, the result shows that the electric car is very beneficial from an environmental and health perspective, compared to the composition of cars in Sweden 2012. However, how beneficial the electric car is, largely depends on the fuel consumption for both the electric car and the alternative compared with. Although to be able to increase the use of electric cars there are many challenges that need to be dealt with. In order to increase the use of electric cars, it will require further work in the development of batteries, expansion of charging points and other incentives, such as legislation and investments. It will also require a significant technology development to increase the range of the electric car. A natural step in the transition phase could be plug-in hybrids. It is also important to continue to implement climate smart districts, such as Brunnshög in Lund. 

  • 14.
    Niklasson, Gunnar A.
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Lansåker, Pia C.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Li, Shu-Yi
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Electronics.
    Granqvist, Claes G.
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Solid State Physics.
    Plasmonic thin films for application to inproved chromogenic windows2015In: INERA Conference: Book of Abstracts / [ed] Nesheva, D; Chamati, H; Genova, J; Gesheva, K; Ivanova, T; Szekeres, A, 2015, article id 012003Conference paper (Refereed)
    Abstract [en]

    Nanocomposites consisting of noble metal nanoparticles in a transparent matrix exhibit plasmonic absorption in the visible wavelength range. On the other hand conducting oxide nanoparticles display a localized plasma absorption in the near infrared. These effects can be exploited in the design of energy-efficient windows in order to obtain improved performance. Electrochromic coatings that switch in the near infrared make use of the modulation of the plasma absorption of oxide nanoparticles due to charge insertion/extraction induced by an external voltage. Thermochromic nanocomposites are predicted to exhibit a much improved energy efficiency, as compared to thermochromics thin films. Plasmonic thermochromics switching in the near infrared has the potential to be significantly larger than in the case of a thin film. Very thin noble metal films are an interesting alternative to conducting oxides as transparent contacts to electrochromic devices. However, in this latter case plasmonic effects are to be avoided rather than exploited.

     

    In order to model and optimize chromogenic devices, a good theoretical understanding of plasmonic effects is necessary. The optical properties of nanocomposites are commonly described by effective medium theories. They describe the effective dielectric function of the composite using as input the dielectric functions of the constituents and their respective volume fractions. However, theoretical modelling by effective medium theories is not straightforward since the effective dielectric function is also sensitively dependent on the actual microgeometry of the composite. These structural effects can be described by the so-called spectral density function. In this paper we describe recent work on three topics related to energy efficient chromogenic window coatings: (1) The performance limits of plasmonic electrochromic coatings, (2) the performance of thermochromics nanocomposites and (3) a study of the optical properties of ultrathin silver films by the spectral density formalism.

  • 15.
    Randau, Karl
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Livscykelanalys av sex olika fiskodlingssystem: Fiskens miljöpåverkan för konsumtion i Stockholm2012Independent thesis Advanced level (professional degree), 20 credits / 30 HE creditsStudent thesis
    Abstract [en]

    This thesis evaluates the environmental performance of six different fish farming systems. The thesis is part of the network group “Hållbar fiskförsörjning I Stockholms län” (HFFS) which tries to increase the domestic and regional production of fish in Stockholm and move to a more sustainable supply in the Stockholm county. Two of the chosen systems; pangasius from Vietnam and salmon from Norway are delivering a substantial part of the fish consumed in Stockholm today, although they are very different when it comes to system characteristics. One system, arctic char with conventional feed, is produced in a fairly small scale in the north of Sweden, while the three remaining systems are viewed upon as possible options to supply Stockholm with fish in the future. Two of these three systems are fed with Baltic Blend which is a new fish feed developed at SLU, Uppsala. The idea of the new feed is to lower the environmental burden by substituting parts of the fish meal with other protein sources such as mussels and microbes. Two of the Swedish systems are recirculating and land-based (RAS), which is a fairly new but growing fish production system worldwide.

    The life cycle assessment in this study shows that domestic production of fish not necessarily is environmentally preferable but has the potential to be so if some processes can be performed more efficiently. The greatest improvement potential is found in the production of the new feed ingredients, the grow-out phase and the slaughter and guttering of the fish. 

  • 16.
    Ranlöf, Martin
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Wallin, Mattias
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Bladh, Johan
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Lundin, Urban
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Experimental Study of the Effect of Damper Windings on Synchronous Generator HuntingIn: Electric power components and systems, ISSN 1532-5008, E-ISSN 1532-5016Article in journal (Refereed)
    Abstract [en]

    The performance of different damper winding designs with respect to the suppression of hunting is studied. The effect of an inter-pole connection between the pole damper cages on the damping capability of a 75 kVA salient-pole synchronous generator is determined experimentally. Results from tests are further compared with transient electromechanical responses obtained in simulations of the test system. The accuracy of the system model as regards electromechanical transient modeling is assessed and specific modeling challenges are highlighted. It is concluded that a high natural damping capability typically is assured if there exists a low-impedance path between the pole damper cages.

  • 17. Roos, Per M.
    et al.
    Lierhagen, Syverin
    Flaten, Trond Peder
    Syversen, Tore
    Vesterberg, Olof
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Nordberg, Monica
    Manganese in cerebrospinal fluid and blood plasma of patients with amyotrophic lateral sclerosis2012In: Experimental biology and medicine (Maywood, N.J.: Print), ISSN 1535-3702, E-ISSN 1535-3699, Vol. 237, no 7, p. 803-810Article in journal (Refereed)
    Abstract [en]

    Neurotoxic properties of manganese (Mn) are well documented. It is less known that Mn contributes to the development of neurodegenerative disorders in the general population. This study presents Mn data from patients with amyotrophic lateral sclerosis (ALS) in a well-defined cohort diagnosed by electrophysiological methods. Cerebrospinal fluid (CSF) and plasma were collected from patients and controls. Mn concentrations were analyzed by high-resolution inductively coupled plasma mass spectrometry. Concentrations of Mn were significantly higher in ALS CSF (median 5.67 mu g/L) than in CSF from controls (median 2.08 mu g/L). Also, ALS CSF Mn concentrations were higher than ALS plasma Mn concentrations (median 0.91 mu g/L), suggesting transport of Mn into the central nervous system. The properties of barrier systems between blood and the brain are discussed and the possibility of Mn accumulation contributing to the relentless course of ALS is introduced.

  • 18. Roos, Per M.
    et al.
    Vesterberg, Olof
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Syversen, Tore
    Flaten, Trond Peder
    Nordberg, Monica
    Metal Concentrations in Cerebrospinal Fluid and Blood Plasma from Patients with Amyotrophic Lateral Sclerosis2013In: Biological Trace Element Research, ISSN 0163-4984, E-ISSN 1559-0720, Vol. 151, no 2, p. 159-170Article in journal (Refereed)
    Abstract [en]

    Amyotrophic lateral sclerosis (ALS) is a progressive and fatal degenerative disorder of motor neurons. The cause of this degeneration is unknown, and different causal hypotheses include genetic, viral, traumatic and environmental mechanisms. In this study, we have analyzed metal concentrations in cerebrospinal fluid (CSF) and blood plasma in a well-defined cohort (n = 17) of ALS patients diagnosed with quantitative electromyography. Metal analyses were performed with high-resolution inductively coupled plasma mass spectrometry. Statistically significant higher concentrations of manganese, aluminium, cadmium, cobalt, copper, zinc, lead, vanadium and uranium were found in ALS CSF compared to control CSF. We also report higher concentrations of these metals in ALS CSF than in ALS blood plasma, which indicate mechanisms of accumulation, e.g. inward directed transport. A pattern of multiple toxic metals is seen in ALS CSF. The results support the hypothesis that metals with neurotoxic effects are involved in the pathogenesis of ALS.

  • 19.
    Sharma, Atul
    et al.
    Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India.
    Nitharwal, Ram G.
    Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India.
    Singh, Bhupender
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Dar, Ashraf
    Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India.
    Dasgupta, Santanu
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Dhar, Suman K.
    Special Centre for Molecular Medicine, Jawaharlal Nehru University, New Delhi, India.
    Helicobacter pylori single-stranded DNA bindingprotein – functional characterization and modulationof H. pylori DnaB helicase activity2009In: The FEBS Journal, ISSN 1742-464X, E-ISSN 1742-4658, Vol. 276, p. 519-531Article in journal (Refereed)
  • 20.
    Singh, Bhupender
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Kirsebom, Leif A.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Dasgupta, Santanu
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Growth and cell division in mycobacteria: Compensatory events for non-medial division sitesManuscript (preprint) (Other academic)
  • 21.
    Wikberg, Magnus
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Fundamental Properties of Functional Magnetic Materials2010Doctoral thesis, comprehensive summary (Other academic)
    Abstract [en]

    Magnetic properties of powders, thin films and single crystals have been investigated using magnetometry methods. This thesis provides analysis and conclusions that are supported by the results obtained from spectroscopic and diffraction measurements as well as from theoretical calculations.

    First, the magnetic behavior of transition metal (TM) doped ZnO with respect to doping, growth conditions and post annealing has been studied. Our findings indicate that the magnetic behavior stems from small clusters or precipitates of the dopant, with ferromagnetic or antiferromagnetic interactions. At the lowest dopant concentrations, the estimated cluster sizes are too small for high resolution imaging. Still, the clusters may be sufficiently large to generate a finite spontaneous magnetization even at room temperature and could easily be misinterpreted as an intrinsic ferromagnetic state of the TM:ZnO compound.

    Second, influence of lattice strain on both magnetic moment and anisotropy has been investigated for epitaxial MnAs thin films grown on GaAs substrates. The obtained magnetic moments and anisotropy values are higher than for bulk MnAs. The enhanced values are caused by highly strained local areas that have a stronger dependence on the in-plane axis strain than out-of plane axis strain.

    Finally, spin glass behavior in Li-layered oxides, used for battery applications, and a double perovskite material has been investigated. For both Li(NiCoMn)O2 and (Sr,La)MnWO6, a mixed-valence of one of the transition metal ions creates competing ferromagnetic and antiferromagnetic interactions resulting in a low temperature three-dimensional (3D) spin glass state. Additionally, Li(NiCoMn)O2 with large cationic mixing exhibits a percolating ferrimagnetic spin order in the high temperature region and coexists with a two-dimensional (2D) frustrated spin state in the mid temperature region. This is one of the rare observations where a dimensional crossover from 2D to 3D spin frustration appears in a reentrant material.

    List of papers
    1. Magnetocrystalline anisotropy and uniaxiality of MnAs/GaAs(100) films
    Open this publication in new window or tab >>Magnetocrystalline anisotropy and uniaxiality of MnAs/GaAs(100) films
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    2011 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 83, no 2, p. 024417-Article in journal (Refereed) Published
    Abstract [en]

    We present an investigation of the magnetic behavior of epitaxial MnAs films grown on GaAs(100). We address the dependence of the magnetic moment, ferromagnetic transition temperature (Tc), and magnetocrystalline anisotropy constants on epitaxial conditions. From thorough structural and magnetic investigations, our findings indicate a more complex relationship between strain and magnetic properties in MnAs films than a simple stretch/compression of the unit cell axes. While a small increase is seen in the anisotropy constants, the enhancement of the magnetic moment at saturation is significant. Results of x-ray magnetic circular dichroism show a behavior of the spin and orbital moment that is consistent with a structural transition at Tc. In particular, we find that the ratio of the orbital to the spin moment shows a marked increase in the coexistence region of the ferromagnetic α- and paramagnetic β-phases a result that is well in accord with the observed increase in the c/a ratio in the same temperature region. The ab initio density functional calculations reveal that the magnetic properties are more sensitive towards change in the ab-plane compared to change in the c-axis which is explained by the analysis of band structures. The effects of electron correlation in MnAs using ab initio dynamical mean field theory are also presented.

    National Category
    Inorganic Chemistry Engineering and Technology
    Research subject
    Chemistry with specialization in Inorganic Chemistry; Engineering Science with specialization in Solid State Physics
    Identifiers
    urn:nbn:se:uu:diva-133316 (URN)10.1103/PhysRevB.83.024417 (DOI)000286755100007 ()
    Available from: 2010-11-06 Created: 2010-11-06 Last updated: 2017-12-12
    2. Annealing effects on structural and magnetic properties of Co implanted ZnO single crystals
    Open this publication in new window or tab >>Annealing effects on structural and magnetic properties of Co implanted ZnO single crystals
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    2011 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 109, no 8, p. 083918-Article in journal (Refereed) Published
    Abstract [en]

    Single crystals of ZnO were implanted with 100 keV-Co ions at room temperature with a fluence of 4.8 x 10(16) cm(-2) and subsequently annealed at different temperatures up to 800 degrees C. The samples were analyzed by Rutherford backscattering spectrometry, secondary ion mass spectrometry, X-ray diffraction, X-ray photoemission spectroscopy and magnetometry. The as-implanted Co:ZnO crystal shows a homogeneous distribution of Co in the near surface region of the crystal. Upon annealing, clear evidence of secondary phases is found. At the highest annealing temperature (800 degrees C) a ferromagnetic behavior is observed at room temperature with a coercive field of 120 Oe assigned mainly to metallic fcc Co nano-crystallites. We find that for the annealed samples, the temperature dependent magnetization cannot be explained within a model containing only a paramagnetic contribution due to well dispersed Co ions and a ferromagnetic contribution due to Co nano-crystallites, at least one more ferromagnetic contribution is needed for a consistent explanation of the experimental results.

    National Category
    Inorganic Chemistry Engineering and Technology
    Research subject
    Chemistry with specialization in Inorganic Chemistry; Engineering Science with specialization in Solid State Physics
    Identifiers
    urn:nbn:se:uu:diva-133317 (URN)10.1063/1.3559263 (DOI)000290047000110 ()
    Available from: 2010-11-06 Created: 2010-11-06 Last updated: 2017-12-12
    3. Magnetic and electronic characterization of highly Co-doped ZnO: An annealing study at the solubility limit
    Open this publication in new window or tab >>Magnetic and electronic characterization of highly Co-doped ZnO: An annealing study at the solubility limit
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    2010 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 82, no 9, p. 094438-Article in journal (Refereed) Published
    Abstract [en]

    We report on investigations of the electronic structure and magnetic properties of ZnO doped with 15 at. % Co and postgrowth annealed at temperatures ranging between 250 and 800°C. In particular, we demonstrate how the presence of Co3+, indicative of secondary phases, is manifested in spectroscopy. Through resonant photoemmision spectroscopy we have found that x-ray diffraction in some cases underestimates or does not reveal the presence of secondary phases, possibly due to unrelaxed structures or structural arrangements with sizes below the detection limit. The magnetic properties are in most cases understood by assuming small antiferromagnetic clusters but can also show a behavior indicative of ferromagnetic interactions.

    National Category
    Physical Sciences Engineering and Technology Inorganic Chemistry
    Research subject
    Chemistry with specialization in Inorganic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-133314 (URN)10.1103/PhysRevB.82.094438 (DOI)000282097200003 ()
    Available from: 2010-11-06 Created: 2010-11-06 Last updated: 2017-12-12
    4. Electronic structure and chemical and magnetic interactions in ZnO doped with Co and Al: Experiments and ab initio density-functional calculations
    Open this publication in new window or tab >>Electronic structure and chemical and magnetic interactions in ZnO doped with Co and Al: Experiments and ab initio density-functional calculations
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    2008 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 78, no 8, p. 085319-Article in journal (Refereed) Published
    Abstract [en]

    We present results of electronic structure and magnetization measurements of Co:ZnO and Co:ZnO codoped with Al thin-film samples fabricated by solution-based methods together with ab initio electronic structure calculations. Electronic structure measurements indicate that the Co states lie close to the valence-band edge with pinning of the Fermi level primarily due to native defects yielding a heavily n-doped material. The findings in the electronic structure measurements are corroborated by results from theoretical calculations. We find that it is necessary to go beyond the local-density approximation to achieve agreement with experiments. Moreover, the theoretical calculations indicate a tendency for the formation of Co clusters, giving rise to an antiferromagnetic exchange interaction between the Co atoms. The magnetization measurements are well in line with the theoretical predictions, showing a dominating superparamagnetic behavior arising from small antiferromagnetic clusters containing uncompensated spins.

    National Category
    Physical Sciences Engineering and Technology
    Identifiers
    urn:nbn:se:uu:diva-107891 (URN)10.1103/PhysRevB.78.085319 (DOI)000259406900078 ()
    Available from: 2009-09-01 Created: 2009-08-31 Last updated: 2017-12-13
    5. Magnetic order, aging, and spin frustration in a percolating spin system, LiNi0.8Co0.1Mn0.1O2
    Open this publication in new window or tab >>Magnetic order, aging, and spin frustration in a percolating spin system, LiNi0.8Co0.1Mn0.1O2
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    2010 (English)In: Journal of Applied Physics, ISSN 0021-8979, E-ISSN 1089-7550, Vol. 108, no 8, p. 083909-Article in journal (Refereed) Published
    Abstract [en]

    Structural and magnetic properties of the Li layered oxide, LiNi0.8Co0.1Mn0.1O2, have been studied by means of x-ray diffraction, dc magnetization, ac linear, and nonlinear susceptibility as well as by magnetic aging and temperature cycling experiments. A percolating spin system interacting via antiferromagnetic and ferromagnetic superexchange interactions of different strength induce a ferrimagnetic quasilong-range order with a transition temperature Tc ≈ 70 K, a Weiss temperature of −25 K and an effective magnetic moment of 2.07 μB. On cooling below Tc the two-dimensional (2D) triangular lattice built up of edge-sharing metal oxide octahedras first exhibits a 2D spin glass like behavior followed by complete spin frustration in three dimensions below 30 K. The findings correlate well with expectations for a ferrimagnetic reentrant cluster glass system as well as with predictions of the percolating cluster model.

    Keywords
    ageing, cobalt compounds, ferrimagnetic materials, frustration, lithium compounds, long-range order, magnetic moments, magnetic susceptibility, magnetisation, manganese compounds, nickel compounds, superexchange interactions, X-ray diffraction
    National Category
    Physical Sciences Inorganic Chemistry Engineering and Technology
    Research subject
    Chemistry with specialization in Inorganic Chemistry; Engineering Science with specialization in Solid State Physics
    Identifiers
    urn:nbn:se:uu:diva-133312 (URN)10.1063/1.3493243 (DOI)000283745100090 ()
    Funder
    StandUp
    Available from: 2010-11-06 Created: 2010-11-06 Last updated: 2017-12-30
    6. Dimensionality crossover and frustrated spin dynamics on a triangular lattice
    Open this publication in new window or tab >>Dimensionality crossover and frustrated spin dynamics on a triangular lattice
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    2010 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 81, no 22, p. 224411-Article in journal (Refereed) Published
    Abstract [en]

    Investigations of the magnetic behavior of the layered oxide, LiNi0.65Co0.25Mn0.10O2, through ac and time-dependent susceptibility, dc linear and nonlinear susceptibility as well as neutron-diffraction measurements are presented. A ferrimagneticlike spin ordering appears at 119 K with a spontaneous magnetization coexisting with spin frustration in two dimensions (2D). At lower temperature, a cluster-glass transition is found at 17.4 K indicating a transformation to a completely frustrated state in three dimensions (3D). A dimensionality crossover with temperature, from 2D to 3D, in a magnetically frustrated system has been demonstrated. The observed magnetic behavior is believed to originate from a percolating system of spin clusters defined by disordered and frustrated exchange interactions and the findings conform well with predictions of the percolation cluster model.

    National Category
    Physical Sciences Inorganic Chemistry Engineering and Technology
    Research subject
    Chemistry with specialization in Inorganic Chemistry; Engineering Science with specialization in Solid State Physics
    Identifiers
    urn:nbn:se:uu:diva-133311 (URN)10.1103/PhysRevB.81.224411 (DOI)000278482500002 ()
    Funder
    StandUp
    Available from: 2010-11-06 Created: 2010-11-06 Last updated: 2017-12-30
    7. A delithiated LiNi0.65Co0.25Mn0.10O2 electrode material: A structural, magnetic and electrochemical study
    Open this publication in new window or tab >>A delithiated LiNi0.65Co0.25Mn0.10O2 electrode material: A structural, magnetic and electrochemical study
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    2009 (English)In: Electrochimica Acta, ISSN 0013-4686, E-ISSN 1873-3859, Vol. 54, no 11, p. 3211-3217Article in journal (Refereed) Published
    Abstract [en]

    A crystalline LiNi0.65Co0.25Mn0.10O2 electrode material was synthesized by the combustion method at 900 °C for 1 h. Rietveld refinement shows less than 3% of Li/Ni disorder in the structure. Lithium extraction involves only the Ni2+/Ni4+ redox couple while Co3+ and Mn4+ remain electrochemically inactive. No structural transition was detected during cycling in the whole composition range 0 < x < 1.0. Furthermore, the hexagonal cell volume changes by only 3% when all lithium was removed indicating a good mechanical stability of the studied compound. LiNi0.65Co0.25Mn0.10O2 has a discharge capacity of 150 mAh/g in the voltage range 2.5–4.5 V, but the best electrochemical performance was obtained with an upper cut-off potential of 4.3 V. Magnetic measurements reveal competing antiferromagnetic and ferromagnetic interactions – varying in strength as a function of lithium content – yielding a low temperature magnetically frustrated state. The evolution of the magnetic properties with lithium content confirms the preferential oxidation of Ni ions compared to Co3+ and Mn4+ during the delithiation process.

    Place, publisher, year, edition, pages
    Elsevier Ltd, 2009
    National Category
    Chemical Sciences Engineering and Technology
    Research subject
    Inorganic Chemistry
    Identifiers
    urn:nbn:se:uu:diva-121033 (URN)10.1016/j.electacta.2008.11.057 (DOI)000265342100039 ()
    Available from: 2010-03-18 Created: 2010-03-18 Last updated: 2017-12-30
    8. Effect of the synthesis temperature on the structure and electrochemical behaviour of the LiNi0.65Co0.25Mn0.1O2 positive electrode material
    Open this publication in new window or tab >>Effect of the synthesis temperature on the structure and electrochemical behaviour of the LiNi0.65Co0.25Mn0.1O2 positive electrode material
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    2008 (English)In: Solid State Ionics, ISSN 0167-2738, E-ISSN 1872-7689, Vol. 178, no 31-32, p. 1668-1675Article in journal (Refereed) Published
    Abstract [en]

    Three kinds of LiNi0.65Co0.25Mn0.1O2 samples were prepared using a combustion method at different synthetic conditions (C1: 900 °C/1 h; C2: 900 °C/12 h and C3: 1000 °C/12 h). The samples were characterized using X-ray diffraction, scanning electron microscopy and magnetization measurements before their use as positive electrode material in lithium-ion batteries. Sample C1 presents the most ordered structure with less than 3% of nickel ions in the lithium plane. Increasing synthesis temperature and/or time lead to an increase of the Li/Ni disorder. The amount of extra-nickel ions in the lithium plane strongly affects the magnetic behaviour and the electrochemical performances of the prepared material. LiNi0.65Co0.25Mn0.1O2 prepared at 900 °C for 1 h presents the best cycling properties.

    Keywords
    Layered oxides, Magnetization, Crystal structure, Li-ion batteries, Electrochemical cycling
    National Category
    Chemical Sciences Engineering and Technology
    Research subject
    Engineering Science with specialization in Solid State Physics
    Identifiers
    urn:nbn:se:uu:diva-12778 (URN)10.1016/j.ssi.2007.10.019 (DOI)000252531200007 ()
    Funder
    StandUp
    Available from: 2008-01-15 Created: 2008-01-15 Last updated: 2017-12-30
    9. Spin-glass transition in a La-doped Sr2MnWO6 double perovskite
    Open this publication in new window or tab >>Spin-glass transition in a La-doped Sr2MnWO6 double perovskite
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    2008 (English)In: Physical Review B. Condensed Matter and Materials Physics, ISSN 1098-0121, E-ISSN 1550-235X, Vol. 77, no 6, p. 064418-Article in journal (Refereed) Published
    Abstract [en]

    Polycrystalline Sr2-xLaxMnWO6 (x=0.25 and 0.5) materials have been prepared by a traditional solid state sintering method and studied by neutron powder diffraction (NPD) and magnetization measurements. Rietveld analysis of the temperature dependent NPD data shows that the compounds crystallize in monoclinic symmetry (space group P2(1)/n). The unit cell volume decreases with increasing La3+ concentration at the A site. The crystal structure contains alternating MnO6 and WO6 octahedra, considerably tilted due to the relative small size of the cations that occupy the A sublattice of the perovskite. ac and dc magnetization measurements show a destruction of the low temperature antiferromagnetic phase by electron doping through substitution of Sr2+ for La3+. The electron doping creates a mixed tungsten valence (W6+/W5+) resulting in a low temperature spin-glass state.

    National Category
    Engineering and Technology
    Research subject
    Engineering Science with specialization in Solid State Physics
    Identifiers
    urn:nbn:se:uu:diva-112392 (URN)10.1103/PhysRevB.77.064418 (DOI)000253764100055 ()
    Available from: 2010-01-13 Created: 2010-01-13 Last updated: 2017-12-12Bibliographically approved
  • 22.
    Wågberg, Linus
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    Olsson, Andreas
    Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology.
    MeasureApp: Utveckling av en Android-applikation för mätning och kartvisning med hjälp av GPS2011Independent thesis Basic level (degree of Bachelor), 10 credits / 15 HE creditsStudent thesis
    Abstract [en]

    The objective of this project was to develop an application for mobile phones using the Android operating system. The main goal was, with the help of GPS, to pinpoint locations, measure distance traveled and illustrate the progress on a map. Functionalities for just showing the map, fetching addresses and saving to a database was also implemented. The result of the work was a proper application, called MeasureApp, that fulfills the goals set in the planning stages of the project. MeasureApp can be used to measure distances where accuracy is not a main factor, i.e walks or runs. The function of showing the map in combination with the ability of getting addresses makes it a good navigational tool as well. Since a GUI takes a lot of effort to design the focus of the project has been to establish a working application with few bugs. As a development environment Eclipse together with the Android SDK has been used. The application has mainly been written in Java except for the GUI which was constructed in XML. 

  • 23.
    Åberg, Jonas
    et al.
    Uppsala University, Disciplinary Domain of Science and Technology. Uppsala University, Disciplinary Domain of Science and Technology, Faculty of Science and Technology. Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    Pankotai, Eszter
    Hulsart Billström, Gry
    Weszl, Miklós
    Larsson, Sune
    Forster-Horváth, Csaba
    Lacza, Zsombor
    Engqvist, Håkan
    Uppsala University, Disciplinary Domain of Science and Technology, Technology, Department of Engineering Sciences, Applied Materials Sciences.
    In vivo evaluation of an injectable premixed radiopaque calcium phosphate cement International Journal of BiomaterialsIn: International Journal of BiomaterialsArticle in journal (Refereed)
1 - 23 of 23
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