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1.
  • Villforth, C., et al. (author)
  • Variability and stability in blazar jets on time-scales of years : optical polarization monitoring of OJ 287 in 2005-2009
  • 2010
  • In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 402:3, s. 2087-2111
  • Journal article (peer-reviewed)abstract
    • OJ 287 is a BL Lac object at redshift z = 0.306 that has shown double-peaked bursts at regular intervals of similar to 12 yr during the last similar to 40 yr. We analyse optical photopolarimetric monitoring data from 2005 to 2009, during which the latest double-peaked outburst occurred. The aim of this study is twofold: firstly, we aim to analyse variability patterns and statistical properties of the optical polarization light curve. We find a strong preferred position angle in optical polarization. The preferred position angle can be explained by separating the jet emission into two components: an optical polarization core and chaotic jet emission. The optical polarization core is stable on time-scales of years and can be explained as emission from an underlying quiescent jet component. The chaotic jet emission sometimes exhibits a circular movement in the Stokes plane. We find six such events, all on the time-scales of 10-20 d. We interpret these events as a shock front moving forwards and backwards in the jet, swiping through a helical magnetic field. Secondly, we use our data to assess different binary black hole models proposed to explain the regularly appearing double-peaked bursts in OJ 287. We compose a list of requirements a model has to fulfil to explain the mysterious behaviour observed in OJ 287. The list includes not only characteristics of the light curve but also other properties of OJ 287, such as the black hole mass and restrictions on accretion flow properties. We rate all existing models using this list and conclude that none of the models is able to explain all observations. We discuss possible new explanations and propose a new approach to understanding OJ 287. We suggest that both the double-peaked bursts and the evolution of the optical polarization position angle could be explained as a sign of resonant accretion of magnetic field lines, a 'magnetic breathing' of the disc.
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  • Debeffe, L., et al. (author)
  • Short- and long-term repeatability of docility in the roe deer: sex and age matter
  • 2015
  • In: Animal Behaviour. - : Elsevier BV. - 0003-3472 .- 1095-8282. ; 109, s. 53-63
  • Journal article (peer-reviewed)abstract
    • Behavioural consistency is a key assumption when evaluating how between-individual differences in behaviour influence life history tactics. Hence, understanding how and why variation in behavioural repeatability occurs is crucial. While analyses of behavioural repeatability are common, few studies of wild populations have investigated variation in repeatability in relation to individual status (e.g. sex, age, condition) and over different timescales. Here, we aimed to fill this gap by assessing within-population variation in the repeatability of docility, as assessed by the individual’s response to human handling, in a free-ranging population of European roe deer, Capreolus capreolus. Docility was an equally repeatable behaviour at both short- and long-term timescales, suggesting that this behavioural trait is stable across time. Repeatability did not differ markedly between age and sex categories but tended to be higher in juvenile males than in juvenile females. Finally, contrary to expectation, individual variation in the repeatability of docility was not correlated with individual body mass. Further studies are required to assess the life history consequences of the individual variation in docility we report here.
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  • Meiland, FJ M., et al. (author)
  • COGKNOW : helping people with mild dementia navigate their day
  • 2007
  • Conference paper (peer-reviewed)abstract
    • Dementia is a progressive, chronic disease affecting 5% of all persons above 65 and over 40% of people over 90. The aim of the COGKNOW project is to achieve a breakthrough with research that addresses the needs of those with dementia, particularly those with mild dementia living in the community. This entails cognitive reinforcement in four main areas: helping people to remember, helping to maintain social contact, helping with performing daily life and recreational activities and finally enhance feelings of safety. Based on a sound foundation of needs reported in dementia literature, workshops and individual interviews have been carried out with dementia sufferers and their carers in three European countries. A ranked analysis of information from workshops and interviews, and the state of the art of successful ICT solutions will be the basis for formulating the functionalities of the technical solution and for the development of a cognitive prosthetic device with associated services for people with mild dementia. The research and evaluation will be conducted from human factors, technology, and business perspectives in three phases of one year each. In this paper we discuss the design of the COGKNOW project, the first results of the user needs inquiry workshops and the ICT solutions the COGKNOW project will focus on in the first year.
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  • Romania, P., et al. (author)
  • Identification of a Genetic Variation in ERAP1 Aminopeptidase that Prevents Human Cytomegalovirus miR-UL112-5p-Mediated Immunoevasion
  • 2017
  • In: Cell Reports. - : Elsevier BV. - 2211-1247. ; 20:4, s. 846-853
  • Journal article (peer-reviewed)abstract
    • Herein, we demonstrate that HCMV miR-UL112-5p targets ERAP1, thereby inhibiting the processing and presentation of the HCMV pp65495-503 peptide to specific CTLs. In addition, we show that the rs17481334 G variant, naturally occurring in the ERAP1 30 UTR, preserves ERAP1 from miR-UL1125p-mediated degradation. Specifically, HCMV miRUL112-5p binds the 30 UTR of ERAP1 A variant, but not the 30 UTR of ERAP1 G variant, and, accordingly, ERAP1 expression is reduced both at RNA and protein levels only in human fibroblasts homozygous for the A variant. Consistently, HCMV-infected GG fibroblasts were more efficient in trimming viral antigens and being lysed by HCMV-peptide-specific CTLs. Notably, a significantly decreased HCMV seropositivity was detected among GG individuals suffering from multiple sclerosis, a disease model in which HCMV is negatively associated with adultonset disorder. Overall, our results identify a resistance mechanism to HCMV miR-UL112-5p-based immune evasion strategy with potential implications for individual susceptibility to infection and other diseases.
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  • Adamo, Angela, et al. (author)
  • Star cluster formation and evolution in Mrk 930 : properties of a metal-poor starburst
  • 2011
  • In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 415:3, s. 2388-2406
  • Journal article (peer-reviewed)abstract
    • We present the analysis of the large population of star clusters in the blue compact galaxy (BCG) Mrk 930. The study has been conducted by means of a photometric analysis of multiband data obtained with the Hubble Space Telescope (HST). We have reconstructed the spectral energy distributions of the star clusters and estimated the age, mass and extinction for a representative sample. Similar to previous studies of star clusters in BCGs, we observe a very young cluster population with 70 per cent of the systems formed less than 10 Myr ago. In Mrk 930, the peak in the star cluster age distribution at 4 Myr is corroborated by the presence of Wolf-Rayet spectral features, and by the observed optical and infrared (IR) line ratios [OIII]/H beta and [Ne III]/[Ne II]. The recovered extinction in these very young clusters shows large variations, with a decrease at older ages. It is likely that our analysis is limited to the optically brightest objects (i.e. systems only partially embedded in their natal cocoons; the deeply embedded clusters being undetected). We map the extinction across the galaxy using low-resolution spectra and the H alpha-to-H beta ratio, as obtained from ground-based narrow band imaging. These results are compared with the extinction distribution recovered from the clusters. We find that the mean optical extinction derived in the starburst regions is close to the averaged value observed in the clusters [more than 80 per cent of the systems have E(B - V) <= 0.2mag], but locally, do not trace the more extinguished clusters. Previous HST studies of BCGs have revealed a population of young and extremely red super star clusters. We detect a considerable fraction of clusters affected by a red excess also in Mrk 930. The nature of the red excess, which turns up at near-IR wavelengths (I band and longwards), remains unknown. We compare the cluster formation history and the star formation history, the latter derived from the fit of spectral population synthesis models to the spectra. We find a general agreement between the two independently estimated quantities. Using the cluster properties, we perform a study of the host environmental properties. We find that the cluster formation efficiency (the fraction of star formation happening in clusters) is significantly higher, suggesting a key role of the environment for the formation of these massive objects.
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  • Ahmed, Trifa M., et al. (author)
  • Automated clean-up, separation and detection of polycyclic aromatic hydrocarbons in particulate matter extracts from urban dust and diesel standard reference materials using a 2D-LC/2D-GC system
  • 2013
  • In: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 405:25, s. 8215-8222
  • Journal article (peer-reviewed)abstract
    • A multidimensional, on-line coupled liquid chromatographic/gas chromatographic system was developed for the quantification of polycyclic aromatic hydrocarbons (PAHs). A two-dimensional liquid chromatographic system (2D-liquid chromatography (LC)), with three columns having different selectivities, was connected on-line to a two-dimensional gas chromatographic system (2D-gas chromatography (GC)). Samples were cleaned up by combining normal elution and column back-flush of the LC columns to selectively remove matrix constituents and isolate well-defined, PAH enriched fractions. Using this system, the sequential removal of polar, mono/diaromatic, olefinic and alkane compounds from crude extracts was achieved. The LC/GC coupling was performed using a fused silica transfer line into a programmable temperature vaporizer (PTV) GC injector. Using the PTV in the solvent vent mode, excess solvent was removed and the enriched PAH sample extract was injected into the GC. The 2D-GC setup consisted of two capillary columns with different stationary phase selectivities. Heart-cutting of selected PAH compounds in the first GC column (first dimension) and transfer of these to the second GC column (second dimension) increased the baseline resolutions of closely eluting PAHs. The on-line system was validated using the standard reference materials SRM 1649a (urban dust) and SRM 1975 (diesel particulate extract). The PAH concentrations measured were comparable to the certified values and the fully automated LC/GC system performed the clean-up, separation and detection of PAHs in 16 extracts in less than 24 h. The multidimensional, on-line 2D-LC/2D-GC system eliminated manual handling of the sample extracts and minimised the risk of sample loss and contamination, while increasing accuracy and precision.
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  • Ahmed, Trifa M., et al. (author)
  • Determination of oxygenated and native polycyclic aromatic hydrocarbons in urban dust and diesel particulate matter standard reference materials using pressurized liquid extraction and LC-GC/MS
  • 2015
  • In: Analytical and Bioanalytical Chemistry. - : Springer Science and Business Media LLC. - 1618-2642 .- 1618-2650. ; 407:2, s. 427-438
  • Journal article (peer-reviewed)abstract
    • The objective of this study was to develop a novel analytical chemistry method, comprised of a coupled high-performance liquid chromatography-gas chromatography/mass spectrometry system (LC-GC/MS) with low detection limits and high selectivity, for the identification and determination of oxygenated polycyclic aromatic hydrocarbons (OPAHs) and polycyclic aromatic hydrocarbons (PAHs) in urban air and diesel particulate matter. The linear range of the four OPAHs, which include 9,10-anthraquinone, 4H-cyclopenta[def]phenanthrene-4-one, benzanthrone, and 7,12-benz[a]anthraquinone, was 0.7 pg-43.3 ng with limits of detection (LODs) and limits of quantification (LOQs) on the order of 0.2-0.8 and 0.7-1.3 pg, respectively. The LODs in this study are generally lower than values reported in the literature, which can be explained by using large-volume injection. The recoveries of the OPAHs spiked onto glass fiber filters using two different pressurized liquid extraction (PLE) methods were in the ranges of 84-107 and 67-110 %, respectively. The analytical protocols were validated using the following National Institute of Standards and Technology standard reference materials: SRM 1649a (Urban Dust), SRM 1650b (Diesel Particulate Matter), and SRM 2975 (Diesel Particulate Matter, Industrial Forklift). The measured mass fractions of the OPAHs in the standard reference materials (SRMs) in this present study are higher than the values from the literature, except for benzanthrone in SRM 1649a (Urban Dust). In addition to the OPAHs, 44 PAHs could be detected and quantified from the same particulate extract used in this protocol. Using data from the literature and applying a two-sided t test at the 5 % level using Bonferroni correction, significant differences were found between the tested PLE methods for individual PAHs. However, the measured mass fractions of the PAHs were comparable, similar to, or higher than those previously reported in the literature.
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  • Ahmed, Trifa M., et al. (author)
  • Native and oxygenated polycyclic aromatic hydrocarbons in ambient air particulate matter from the city of Sulaimaniyah in Iraq
  • 2015
  • In: Atmospheric Environment. - : Elsevier BV. - 1352-2310 .- 1873-2844. ; 116, s. 44-50
  • Journal article (peer-reviewed)abstract
    • The concentrations of 43 polycyclic aromatic hydrocarbons (PAHs) and 4 oxygenated PAHs (OPAHs) are reported for the first time in particulate matter (PM10) sampled in the air of the city of Sulaimaniyah in Iraq. The total PAH concentration at the different sampling sites varied between 9.3 and 114 ng/m(3). The corresponding values of the human carcinogen benzotalpyrene were between 0.3 and 6.9 ng/m(3), with most samples exceeding the EU annual target value of 1 ng/m(3). The highly carcinogenic dibenzopyrene isomers dibenzo[a,l]pyrene, dibenzo[a,e]pyrene, dibenzo[a,i]pyrene and dibenzo[a,h]pyrene constituted 0.1-0.4% of the total PAH concentration. However, when scaling for relative cancer potencies using toxic equivalency factors, a benzo[a]pyrene equivalent concentration of dibenzo[a,l]pyrene equal to that of benzo[a]pyrene was obtained, indicating that the contribution of dibenzo[a,l]pyrene to the carcinogenicity of the PAHs could be similar to that of benzo[a]pyrene. A high correlation between the determined concentrations of the dibenzopyrene isomers and benzo[a]pyrene was found, which supported the use of benzo[a]pyrene as an indicator for the carcinogenicity of PAHs in ambient air. The total concentrations of the four OPAHs, 9,10-anthraquinone, 4H-cyclopenta[def]phenanthren-4-one, benzanthrone, and 7,12-benz[a]anthraquinone, varied between 0.6 and 8.1 ng/m(3), with 9,10-anthraquinone being the most abundant OPAH in all of the samples.
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  • Bergvall, Anders, 1981, et al. (author)
  • Influence of 0001 tilt grain boundaries on the destruction of the quantum Hall effect in graphene
  • 2015
  • In: Physical Review B - Condensed Matter and Materials Physics. - 2469-9950 .- 2469-9969. ; 91:24
  • Journal article (peer-reviewed)abstract
    • The half-integer quantum Hall effect (QHE) is often suppressed in graphene grown by chemical vapor deposition on metals. The reason behind the suppression is unclear, and we hypothesize that it might be connected to extended defects in the material. In this paper we present results for the quantum Hall effect in graphene with [0001] tilt grain boundaries connecting opposite sides of Hall bar devices. Such grain boundaries contain 5-7 ring complexes that host defect states that hybridize to form bands with varying degree of metallicity depending on grain-boundary defect density. In a magnetic field, edge states on opposite sides of the Hall bar can be connected by the defect states along the grain boundary. This destroys Hall resistance quantization and leads to nonzero longitudinal resistance. Anderson disorder can partly recover quantization, where current instead flows along returning paths along the grain boundary depending on defect density in the grain boundary and on disorder strength. Since grain sizes in graphene made by chemical vapor deposition are usually small, this may help explain why the quantum Hall effect is usually poorly developed in devices made of this material.
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  • Bergvall, M., et al. (author)
  • Better survival for patients with colon cancer operated on by specialized colorectal surgeons - a nationwide population-based study in Sweden 2007-2010
  • 2019
  • In: Colorectal Disease. - : Wiley. - 1462-8910 .- 1463-1318. ; 21:12, s. 1379-1386
  • Journal article (peer-reviewed)abstract
    • Aim Mortality and complication rates after surgery for colon cancer are high, especially after emergency procedures. The aim of the present study was to evaluate the importance of the formal competence of surgeons for survival and morbidity. Method The Swedish Colorectal Cancer Registry prospectively records data on patients diagnosed with cancer within the colon and rectum. A cohort of patients operated on for colon cancer between 2007 and 2010 were followed 5 years after surgery. Data on postoperative morbidity, mortality and long-term survival were compared with regard to formal competency of the most senior surgeon attending the procedure. Results This analysis includes 13 365 patients operated on for colon cancer, including 10 434 elective procedures and 2931 emergency cases. The overall 5-year survival was higher for those operated on by subspecialist colorectal surgeons compared with general surgeons (60% vs 48%; P < 0.001). Five-year survival after elective surgery was 63% vs 55% (P < 0.001) and 35% vs 31% (P < 0.05) after emergency procedures when performed by colorectal surgeons compared with general surgeons. Postoperative 30-day mortality was 3% after surgery performed by colorectal surgeons compared with 7% when performed by general surgeons. Mortality at 90 days was 6% after surgery performed by colorectal surgeons compared with 11% for patients operated on by general surgeons (P < 0.001). Conclusion Subspecialization in colorectal surgery is associated with better outcome for patients operated on for colon cancer, and effort should be made to increase the availability of colorectal surgeons for both acute and elective colon cancer surgery.
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  • Bergvall, M., et al. (author)
  • Validity of classification of distal radial fractures in the Swedish fracture register
  • 2021
  • In: Bmc Musculoskeletal Disorders. - : Springer Science and Business Media LLC. - 1471-2474. ; 22:1
  • Journal article (peer-reviewed)abstract
    • BackgroundDistal radial fractures (DRF) are one of the most common fractures with a small peak in incidence among young males and an increasing incidence with age among women. The reliable classification of fractures is important, as classification provides a framework for communicating effectively on clinical cases. Fracture classification is also a prerequisite for data collection in national quality registers and for clinical research. Since its inception in 2011, the Swedish Fracture Register (SFR) has collected data on more than 490,000 fractures. The attending physician classifies the fracture according to the AO/OTA classification upon registration in the SFR. Previous studies regarding the classification of distal radial fractures (DRF) have shown difficulties in inter- and intra-observer agreement. This study aims to assess the accuracy of the registration of DRF in adults in the SFR as it is carried out in clinical practice.MethodsA reference group of three experienced orthopaedic trauma surgeons classified 128 DRFs, randomly retrieved from the SFR, at two classification sessions 6 weeks apart. The classification the reference group agreed on was regarded as the gold standard classification for each fracture. The accuracy of the classification in the SFR was defined as the agreement between the gold standard classification and the classification in the SFR. Inter- and intra-observer agreement was evaluated and the degree of agreement was calculated as Cohen's kappa.ResultsThe accuracy of the classification of DRF in the SFR was kappa=0.41 (0.31-0.51) for the AO/OTA subgroup/group and kappa=0.48 (0.36-0.61) for the AO/OTA type. This corresponds to moderate agreement. Inter-observer agreement ranged from kappa 0.22-0.48 for the AO/OTA subgroup/group and kappa 0.48-0.76 for the AO/OTA type. Intra-observer agreement ranged from kappa 0.52-0.70 for the AO/OTA subgroup/group and kappa 0.71-0.76 for the AO/OTA type.ConclusionsThe study shows moderate accuracy in the classification of DRF in the SFR. Although the degree of accuracy for DRF appears to be lower than for other fracture locations, the accuracy shown in the current study is similar to that in previous studies of DRF.
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  • Jagannathan, Vidhya, et al. (author)
  • A Mutation in the SUV39H2 Gene in Labrador Retrievers with Hereditary Nasal Parakeratosis (HNPK) Provides Insights into the Epigenetics of Keratinocyte Differentiation
  • 2013
  • In: PLOS Genetics. - : Public Library of Science (PLoS). - 1553-7390 .- 1553-7404. ; 9:10, s. e1003848-
  • Journal article (peer-reviewed)abstract
    • Hereditary nasal parakeratosis (HNPK), an inherited monogenic autosomal recessive skin disorder, leads to crusts and fissures on the nasal planum of Labrador Retrievers. We performed a genome-wide association study (GWAS) using 13 HNPK cases and 23 controls. We obtained a single strong association signal on chromosome 2 (p(raw) = 4.4x10(-14)). The analysis of shared haplotypes among the 13 cases defined a critical interval of 1.6 Mb with 25 predicted genes. We re-sequenced the genome of one case at 38x coverage and detected 3 non-synonymous variants in the critical interval with respect to the reference genome assembly. We genotyped these variants in larger cohorts of dogs and only one was perfectly associated with the HNPK phenotype in a cohort of more than 500 dogs. This candidate causative variant is a missense variant in the SUV39H2 gene encoding a histone 3 lysine 9 (H3K9) methyltransferase, which mediates chromatin silencing. The variant c.972T>G is predicted to change an evolutionary conserved asparagine into a lysine in the catalytically active domain of the enzyme (p.N324K). We further studied the histopathological alterations in the epidermis in vivo. Our data suggest that the HNPK phenotype is not caused by hyperproliferation, but rather delayed terminal differentiation of keratinocytes. Thus, our data provide evidence that SUV39H2 is involved in the epigenetic regulation of keratinocyte differentiation ensuring proper stratification and tight sealing of the mammalian epidermis.
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  • Leitet, Elisabet, et al. (author)
  • Escape of Lyman continuum radiation from local galaxies : Detection of leakage from the young starburst Tol 1247-232
  • 2013
  • In: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 553
  • Journal article (peer-reviewed)abstract
    • Context. It has been suggested that the escape fraction of hydrogen ionizing photons (f(esc)) from galaxies is evolving with time, but the picture is far from clear. While evidence for significant escape fractions has been found at high redshifts in several studies, the picture looks different in the closer universe. The lack of local detections could in principle be a combined effect of an evolving escape fraction, the low number galaxies observed, the selection criteria of these targets, and technical problems associated with the instrument best adapted for low redshift targets, the Far Ultraviolet Spectroscopic Explorer (FUSE). Aims. In an attempt to tackle the last of these effects, we apply a new background routine developed for FUSE data to study galaxies from the archive in search of possible Lyman continuum (LyC) leakage. In the process, for the first time a stacked spectrum in the LyC has been produced for local galaxies. With this small sample, we also make a more tentative approach to looking for possible correlations between f(esc) and physical parameters, such as internal absorption E(B - V)(i), mass, H I mass, specific star formation rate (SSFR), metallicity, and Ly alpha emission. Methods. Eight star forming galaxies with redshifts z > 0.015 from the FUSE archive were re-examined. Also, a subsample of an additional four galaxies with lower redshifts were included, for which the escape fraction was estimated from residual flux in the low ionization interstellar C II lambda 1036 angstrom line. Results. Out of the eight galaxies, only one was found to have significant LyC leakage, Tol 1247-232 (S/N = 5.2). This is the second detection of a leaking galaxy in the local universe. From the first case, Haro 11, we derive an intrinsic Lyman break amplitude for starbursts at this young age of (f(1500) (angstrom)/f(900) (angstrom))(int) = 1.5(-0.5)(+0.6), which gives an absolute escape fraction for Tol 1247-232 of f(esc) = 2.4(-0.8)(+0.9) %. Tol 1247-232 exhibits an extremely blue far-UV slope reminiscent of high redshift LyC leaking galaxies, and although it does not classify as an AGN in the BPT diagram or by other available diagnostics, a minor AGN cannot be completely excluded. The stacked sample shows an excess in the LyC with f(esc) = 1.4(-0.5)(+0.6) %, but we note that there might be important selection biases involved, since the galaxies were originally handpicked for their star forming qualities. With the small sample, we suggest a possible trend toward higher f(esc) with lower mass and with enhanced SSFR. None of the galaxies with high values of E(B - V)(i) were found to show any sign of leakage.
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  • Lewis, Jeffrey, et al. (author)
  • PFAS – A threat for groundwater and drinking water supply in Sweden?
  • 2015
  • In: EGU General Assembly 2015. ; 17
  • Conference paper (other academic/artistic)abstract
    • Perfluoroalkyl substances (PFAS) are a group of anthropogenic environmental pollutants that are widely distributed in the global environment. They have multiple industrial uses, including water repellents in clothing, paper coatings and firefighting foam. According to a study released by the Environmental Directorate of the OECD, they are persistent, bioaccumulative and toxic to mammalian species (OECD, 2002). In some municipal drinking water wells in Sweden, measured concentrations of PFAS found to be several hundred times higher than the allowed threshold values. This has created a huge public concern and has recently attracted much media attention in Sweden (e.g. Afzelius et al., 2014; Bergman et al., 2014; Lewis et al., 2014). PFAS findings raised questions such as “What can we do to solve the problem?” When it comes to drinking water, there are a number of techniques that can ensure that PFAS levels are reduced to acceptable levels. This may be a costly challenge, but from a technical point of view it is possible. To ensure the safety of drinking water from a public health perspective is obviously a top priority. However, international experience shows that the cost of cleaning up PFAS in groundwater may be significantly higher than continuously treat drinking water in water works. Approximately fifty percent of Sweden’s drinking water comes from groundwater. As a result, there are several ongoing and planned PFAS-related environmental and drinking-water investigations in Sweden. Many aquifers that supply municipal water plants are located in areas of sand and gravel deposits. Such soils have relatively high permeabilities, which permits extraction of large volumes of water. However, the downside to high permeabilities is that they also allow dissolved contaminants as PFAS to spread over large areas. If one disregards the health risks linked to its presence in drinking water, PFAS have an impact on three of Sweden’s national environmental quality objectives, namely, A Non-Toxic Environment, Flourishing Lakes and Streams and Good-Quality Groundwater. Although the survey of PFAS in our groundwater supplies will take time, it is feasible. Much research in the field of hydrogeology and geochemistry remains before a viable and cost-effective groundwater remediation method can be operational. Until then, it is essential that measures are taken to identify the present distribution and magnitude of PFAS in groundwater and prevents its further spread in our most important aquifers. Afzelius, H. et al., 2014. Vågar vi dricka kranvattnet? (Do we dare drinking tap water?), Svenska Dagbladet. Bergman, Å., Hansson, S.O., Hellsten, E., 2014. En miljöskandal av historiska mått (An environmental scandal of historic proportions), Svenska Dagbladet. Lewis, J. et al., 2014. Kartlägg det förorenade dricksvattnet (Survey the contaminated drinking water), Svenska Dagbladet. OECD, 2002. Hazard Assessment of Perfluorooctane Sulfonate (PFOS) and its Salt.
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  • Mulvenna, M.D., et al. (author)
  • Living Labs are innovation catalysts
  • 2011
  • In: Innovation through Knowledge Transfer 2010. - Berlin, Heidelberg : Springer Science+Business Media B.V.. - 9783642205071 ; , s. 253-264
  • Book chapter (peer-reviewed)abstract
    • Living labs are increasingly facilitating new ways to stimulate innovation. They offer the possibility to catalyse how innovation can be carried out, focusing on user communities supported by information technology. However, living labs are poorly understood by the business community, in particular by small to medium companies who arguably have the potential to benefit most from accessing the services provided by living labs. This position paper sets out the context for the rising popularity of living labs, explaining how public-private-academic partnerships offer new ways or carrying out innovation activities that are increasingly user-orientated. The paper also discusses the issues and opportunities arising from this new approach.
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  • Osman, Ahmed M. Shahat, et al. (author)
  • Big Data Analytics and Smart Cities : A Loose or Tight Couple?
  • 2017
  • In: Proceedings of the International Conference on ICT, Society and Human Beings 2017. - : IADIS. - 9789898533678 ; , s. 157-168
  • Conference paper (peer-reviewed)abstract
    • Smart City (SC) is an emerging concept aiming at mitigating the challenges raised due to the continuous urbanization development. To face these challenges, government decision makers sponsor SC projects targeting sustainable economic growth and better quality of life for inhabitants and visitors. Information and Communication Technologies (ICT) is the enabling technology for smartening. These technologies yield massive volumes of data known as Big Data (BD). If spawned BD are integrated and analyzed, both city decision makers and citizens can benefit from valuable insights and information services. The process of extracting information and insights from BD is known as Big Data Analytics (BDA). Although BDA involves non-trivial challenges, it attracted academician and industrialist. Surveying the literature reveals the novelty and increasing interest in addressing BD applications in SCs. Although literature is replete with abundant number of articles about SCs applications harnessing BD, comprehensive discussion on BDA frameworks fitting SCs requirements is still needed. This paper attempts to fill this gap. It is a systematic literature review on BDA frameworks in SCs. In this review, we will try to answer the following research questions: what are the big data analytics frameworks applied in smart cities? what are the functional gaps in the current available frameworks? what are the conceptual guidelines of designing integrated scalable big data analytics frameworks for smart cities purposes? The paper concludes with a proposal for a novel conceptual analytics framework to serve SCs requirements. Additionally, open issues and further research directions are presented.
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  • Pardy, Stephen A., et al. (author)
  • Detection Of H I In Emission In The LY Alpha Emitting Galaxy Haro 11
  • 2016
  • In: Astronomical Journal. - : American Astronomical Society. - 0004-6256 .- 1538-3881. ; 152:6
  • Journal article (peer-reviewed)abstract
    • We present the first robust detection of H I 21 cm emission in the blue compact galaxy Haro 11 using the 100 m Robert C. Byrd Green Bank Telescope (GBT). Haro 11 is a luminous blue compact galaxy with emission in both Ly alpha and the Lyman continuum. We detect (5.1 +/- 0.7 x 10(8)) M-circle dot of H I gas at an assumed distance of 88 Mpc, making this galaxy H I deficient compared to other local galaxies with similar optical properties. Given this small H I mass, Haro 11 has an elevated MH2/MH I ratio and a very low gas fraction compared to most local galaxies, and contains twice as much mass in ionized hydrogen as in neutral hydrogen. The H I emission has a linewidth of 71 km s(-1) and is offset 60 km s(-1) redward of the optical line center. It is undergoing a starburst after a recent merger that has elevated the star formation rate, and will deplete the gas supply in <0.2 Gyr. Although this starburst has elevated the star formation rate (SFR) compared to galaxies with similar H I masses and line widths, Haro 11 matches a trend of lower gas fractions toward higher SFRs and is below the general trend of increasing H I mass with increasing luminosity. Taken together, our results paint Haro 11 as a standard low-mass galaxy that is undergoing an unusually efficient star formation episode.
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33.
  • Puschnig, Johannes, et al. (author)
  • The Lyman continuum escape and ISM properties in Tololo 1247-232-new insights from HST and VLA
  • 2017
  • In: Monthly notices of the Royal Astronomical Society. - : Oxford University Press (OUP). - 0035-8711 .- 1365-2966. ; 469:3, s. 3252-3269
  • Journal article (peer-reviewed)abstract
    • Low- and intermediate-mass galaxies are widely discussed as cause of reionization at redshift z similar to 10-6. However, observational proof of galaxies that are leaking ionizing radiation (Lyman continuum; LyC) is a currently ongoing challenge and the list of LyC emitting candidates is still short. Tololo 1247-232 is among those very few galaxies with recently reported leakage. We performed intermediate resolution ultraviolet spectroscopy with the Cosmic Origins Spectrograph onboard the Hubble Space Telescope and confirm ionizing radiation emerging from Tololo 1247-232. Adopting an improved data reduction procedure, we find that LyC escapes from the central stellar clusters, with an escape fraction of 1.5 +/- 0.5 per cent only, i.e. the lowest value reported for the galaxy so far. We further make use of far-ultraviolet absorption lines of Si II and Si IV as a probe of the neutral and ionized interstellar medium ( ISM). We find that most of the ISM gas is ionized, likely facilitating LyC escape from density bounded regions. Neutral gas covering as a function of line-of-sight velocity is derived using the apparent optical depth method. The ISM is found to be sufficiently clumpy, supporting the direct escape of LyC photons. We further report on broad-band UV and optical continuum imaging as well as narrow-band imaging of Lya, Ha and H beta. Using stellar population synthesis, an Lya escape fraction of 8 per cent was derived. We also performed Very Large Array 21cm imaging. The hydrogen hyperfine transition was not detected, but a deep upper limit atomic gas mass of less than or similar to 10(9) M-circle dot could be derived. The upper limit gas fraction defined as M-HI/M-* is only 20 per cent. Evidence is found that the HI gas halo is relatively small compared to the Lyman Alpha Reference Sample (Hayes et al. 2013, 2014; Ostlin et al. 2014).
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34.
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35.
  • Stutz, Rebecca S., et al. (author)
  • Borrowed plant defences : Deterring browsers using a forestry by-product
  • 2017
  • In: Forest Ecology and Management. - : Elsevier BV. - 0378-1127 .- 1872-7042. ; 390, s. 1-7
  • Journal article (peer-reviewed)abstract
    • Mammalian browsers can cause ecologically and economically significant damage to important tree species, particularly at the vulnerable seedling stage. Some tree species or particular parts of trees are less preferred as a result of chemical defences - harnessing such defences could reduce the appeal of more preferred trees and thus their loss to browsing. We tested the potential of birch bark extract, a forestry by-product, to protect seedlings of Scots pine Pinus sylvestris from two globally significant browsers: moose Alces alces and red deer Cervus elaphus. We quantified the responses by captive animals to extract application as a function of both the distance between seedlings and whether the extract was applied to all or alternate seedlings. Both moose and red deer consumed pine seedlings less frequently when seedlings were treated with birch bark extract, but their responses differed when only alternate seedlings were treated. At inter-seedling distances equivalent to those used in forestry, red deer browsed untreated seedlings more frequently when alternate seedlings were treated than when none were treated (associational susceptibility), whereas moose browsed untreated seedlings less frequently with treated than untreated neighbours (associational refuge). These neighbourhood effects were not evident at inter-seedling distances three times larger or smaller than those used in forestry. There was also no significant difference in the frequency of browsing on treated seedlings in alternate compared to completely treated arrangements at any inter-seedling distance. Red deer removed significantly less foliage from treated than untreated seedlings once browsed. Browsing by moose followed a similar but non-significant trend. The relative number of untreated to treated seedlings browsed was 2:1 for red deer and 4:1 for moose. Red deer used a finer scale of selection than moose for choosing between seedlings, consistent with their smaller body mass. However, the coarser-scale of selection used by moose resulted in consumption of more untreated relative to treated seedlings. Our study highlights the potential of existing plant defensive chemistry, harvested from forestry by-products, to reduce herbivore damage to tree seedlings. We also demonstrate the need to consider both plant associational effects and the foraging strategies of the dominant herbivores in applying repellents.
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36.
  • Tengvall, Katarina, 1980-, et al. (author)
  • Transcriptomes from German shepherd dogs reveal differences in immune activity between atopic dermatitis affected and control skin
  • 2020
  • In: Immunogenetics. - : Springer Science and Business Media LLC. - 0093-7711 .- 1432-1211. ; 72:5, s. 315-323
  • Journal article (peer-reviewed)abstract
    • Canine atopic dermatitis (CAD) is an inflammatory and pruritic allergic skin disease with both genetic and environmental risk factors described. We performed mRNA sequencing of non-lesional axillary skin biopsies from nine German shepherd dogs. Obtained RNA sequences were mapped to the dog genome (CanFam3.1) and a high-quality skin transcriptome was generated with 23,510 expressed gene transcripts. Differentially expressed genes (DEGs) were defined by comparing three controls to five treated CAD cases. Using a leave-one-out analysis, we identified seven DEGs: five known to encode proteins with functions related to an activated immune system (CD209, CLEC4G, LOC102156842 (lipopolysaccharide-binding protein-like), LOC480601 (regakine-1-like), LOC479668 (haptoglobin-like)), one (OBP) encoding an odorant-binding protein potentially connected to rhinitis, and the last (LOC607095) encoding a novel long non-coding RNA. Furthermore, high mRNA expression of inflammatory genes was found in axillary skin from an untreated mild CAD case compared with healthy skin. In conclusion, we define genes with different expression patterns in CAD case skin helping us understand post-treatment atopic skin. Further studies in larger sample sets are warranted to confirm and to transfer these results into clinical practice.
  •  
37.
  • Tesch, J., et al. (author)
  • Impurity scattering and size quantization effects in a single graphene nanoflake
  • 2017
  • In: Physical Review B. - 2469-9969 .- 2469-9950. ; 95:7
  • Journal article (peer-reviewed)abstract
    • By using Fourier-transform scanning tunneling spectroscopy we measure the interference patterns produced by the impurity scattering of confined Dirac quasiparticles in epitaxial graphene nanoflakes. Upon comparison of the experimental results with tight-binding calculations of realistic model flakes, we show that the characteristic features observed in the Fourier-transformed local density of states are related to scattering between different transverse modes (subbands) of a graphene nanoflake and allow direct insight into the gapped electronic spectrum of graphene. We also observe a strong reduction of quasiparticle lifetime which is attributed to the interaction with the underlying substrate. In addition, we show that the distribution of the on-site energies at flower defects leads to an effectively broken pseudospin selection rule, where intravalley backscattering is allowed.
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38.
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39.
  • Umbuzeiro, Gisela A., et al. (author)
  • Sensitivity of salmonella YG5161 for detecting PAH-associated mutagenicity in air particulate matter
  • 2014
  • In: Environmental and Molecular Mutagenesis. - Stockholm : Wiley. - 0893-6692 .- 1098-2280. ; 55:6, s. 510-517
  • Journal article (peer-reviewed)abstract
    • The Salmonella/microsome assay is the most used assay for the evaluation of air particulate matter (PM) mutagenicity and a positive correlation between strain TA98 responses and benzo[a]pyrene (B[a]P) levels in PM has been found. However, it seems that the major causes of PM mutagenicity in this assay are the nitro and oxy-PAHs. Salmonella YG5161, a 30-times more responsive strain to B[a]P has been developed. To verify if YG5161 strain was sufficiently sensitive to detect mutagenicity associated with B[a]P mutagenicity, PM samples were collected in Brazil and Sweden, extracted with toluene and tested in the Salmonella/microsome microsuspension assay. PAHs and B[a]P were determined and the extracts were tested with YG5161 and its parental strain TA1538. The extracts were also tested with YG1041 and its parental strain TA98. For sensitivity comparisons, we tested B[a]P and 1-nitropyrene (1-NP) using the same conditions. The minimal effective dose of B[a]P was 155 ng/plate for TA1538 and 7 ng/plate for YG5161. Although the maximum tested dose, 10 m3/plate containing 9 ng of B[a]P in the case of Brazilian sample, was sufficient to elicit a response in YG5161, mutagenicity was detected at a dose as low as 1 m3/plate (0.9 ng). This is probably caused by nitro-compounds that have been shown to be even more potent than B[a]P for YG5161. It seems that the mutagenicity of B[a]P present in PM is not detectable even with the use of YG5161 unless more efficient separation to remove the nitro-compounds from the PAH extract is performed.
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