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2.
  • Butler, P. A., et al. (författare)
  • The observation of vibrating pear-shapes in radon nuclei
  • 2019
  • Ingår i: Nature Communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 10:1
  • Tidskriftsartikel (refereegranskat)abstract
    • There is a large body of evidence that atomic nuclei can undergo octupole distortion and assume the shape of a pear. This phenomenon is important for measurements of electric-dipole moments of atoms, which would indicate CP violation and hence probe physics beyond the Standard Model of particle physics. Isotopes of both radon and radium have been identified as candidates for such measurements. Here, we observed the low-lying quantum states in 224Rn and 226Rn by accelerating beams of these radioactive nuclei. We show that radon isotopes undergo octupole vibrations but do not possess static pear-shapes in their ground states. We conclude that radon atoms provide less favourable conditions for the enhancement of a measurable atomic electric-dipole moment.
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5.
  • Gomez-Gener, L., et al. (författare)
  • Global carbon dioxide efflux from rivers enhanced by high nocturnal emissions
  • 2021
  • Ingår i: Nature Geoscience. - : Springer Science and Business Media LLC. - 1752-0894 .- 1752-0908. ; 14, s. 289-294
  • Tidskriftsartikel (refereegranskat)abstract
    • Carbon dioxide (CO2) emissions to the atmosphere from running waters are estimated to be four times greater than the total carbon (C) flux to the oceans. However, these fluxes remain poorly constrained because of substantial spatial and temporal variability in dissolved CO2 concentrations. Using a global compilation of high-frequency CO2 measurements, we demonstrate that nocturnal CO2 emissions are on average 27% (0.9 gC m(-2) d(-1)) greater than those estimated from diurnal concentrations alone. Constraints on light availability due to canopy shading or water colour are the principal controls on observed diel (24 hour) variation, suggesting this nocturnal increase arises from daytime fixation of CO2 by photosynthesis. Because current global estimates of CO2 emissions to the atmosphere from running waters (0.65-1.8 PgC yr(-1)) rely primarily on discrete measurements of dissolved CO2 obtained during the day, they substantially underestimate the magnitude of this flux. Accounting for night-time CO2 emissions may elevate global estimates from running waters to the atmosphere by 0.20-0.55 PgC yr(-1). Failing to account for emission differences between day and night will lead to an underestimate of global CO2 emissions from rivers by up to 0.55 PgC yr(-1), according to analyses of high-frequency CO2 measurements.
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6.
  • Butler, P. A., et al. (författare)
  • Evolution of Octupole Deformation in Radium Nuclei from Coulomb Excitation of Radioactive ^{222}Ra and ^{228}Ra Beams
  • 2020
  • Ingår i: Physical Review Letters. - 1079-7114. ; 124:4
  • Tidskriftsartikel (refereegranskat)abstract
    • There is sparse direct experimental evidence that atomic nuclei can exhibit stable "pear" shapes arising from strong octupole correlations. In order to investigate the nature of octupole collectivity in radium isotopes, electric octupole (E3) matrix elements have been determined for transitions in ^{222,228}Ra nuclei using the method of sub-barrier, multistep Coulomb excitation. Beams of the radioactive radium isotopes were provided by the HIE-ISOLDE facility at CERN. The observed pattern of E3 matrix elements for different nuclear transitions is explained by describing ^{222}Ra as pear shaped with stable octupole deformation, while ^{228}Ra behaves like an octupole vibrator.
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7.
  • Guseva, S., et al. (författare)
  • Variable Physical Drivers of Near-Surface Turbulence in a Regulated River
  • 2021
  • Ingår i: Water resources research. - : American Geophysical Union (AGU). - 0043-1397 .- 1944-7973. ; 57:11
  • Tidskriftsartikel (refereegranskat)abstract
    • Inland waters, such as lakes, reservoirs and rivers, are important sources of climate forcing trace gases. A key parameter that regulates the gas exchange between water and the atmosphere is the gas transfer velocity, which itself is controlled by near-surface turbulence in the water. While in lakes and reservoirs, near-surface turbulence is mainly driven by atmospheric forcing, in shallow rivers and streams it is generated by bottom friction of gravity-forced flow. Large rivers represent a transition between these two cases. Near-surface turbulence has rarely been measured in rivers and the drivers of turbulence have not been quantified. We analyzed continuous measurements of flow velocity and quantified turbulence as the rate of dissipation of turbulent kinetic energy over the ice-free season in a large regulated river in Northern Finland. Measured dissipation rates agreed with predictions from bulk parameters, including mean flow velocity, wind speed, surface heat flux, and with a one-dimensional numerical turbulence model. Values ranged from to . Atmospheric forcing or gravity was the dominant driver of near-surface turbulence for similar fraction of the time. Large variability in near-surface dissipation rate occurred at diel time scales, when the flow velocity was strongly affected by downstream dam operation. By combining scaling relations for boundary-layer turbulence at the river bed and at the air-water interface, we derived a simple model for estimating the relative contributions of wind speed and bottom friction of river flow as a function of depth.Plain Language SummaryInland water bodies such as lakes, reservoirs and rivers are an important source of climate forcing trace gases to the atmosphere. Gas exchange between water and the atmosphere is regulated by the gas transfer velocity and the concentration difference between the water surface and the atmosphere. The gas transfer velocity depends on near-surface turbulence, but robust formulations have not been developed for river systems. Their surface area is sufficiently large for meteorological forcing to cause turbulence, as in lakes and reservoirs, but turbulence generated from bed and internal friction of gravity-driven flows is also expected to contribute. Here we quantify near-surface turbulence using data from continuous air and water side measurements conducted over the ice-free season in a large subarctic regulated river in Finland. We find that turbulence, quantified as the dissipation rate of turbulent kinetic energy, is well described using equations for predicting turbulence from meteorological data for sufficiently high wind speeds whereas the contribution from bottom shear dominated at higher flow velocities. A one-dimensional river model successfully captured these processes. We provide a fundamental model for estimating the relative contributions of atmospheric forcing and bottom friction as a function of depth.
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8.
  • Hilton, J., et al. (författare)
  • α -spectroscopy studies of the new nuclides Pt 165 and Hg 170
  • 2019
  • Ingår i: Physical Review C. - 2469-9985. ; 100:1
  • Tidskriftsartikel (refereegranskat)abstract
    • The new nuclides Pt165 and Hg170 were produced in the reactions Mo92(Kr78,5n) and Ru96(Kr78,4n) at bombarding energies of 418 MeV and 390 MeV, respectively. For Hg170 an α-particle energy of Eα=7590(30)keV and half-life of t1/2=0.08-0.04+0.40ms were deduced, while for Pt165 the corresponding values were 7272(14) keV and 0.26-0.09+0.26ms. Comparison of the reduced α-decay widths with systematics indicates that both α decays are unhindered. Although combining the measured α-decay Q values with extrapolated masses suggests that both new nuclides are unbound to two-proton emission by more than 1 MeV, their α-decay half-lives are too short for this decay mode to compete. Improved data were also obtained for Pt166,167, produced via the Ru96(Kr78,α4n) and Ru96(Kr78,α3n) reactions at bombarding energies of 390 MeV and 418 MeV.
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9.
  • Rosentau, A., et al. (författare)
  • A Holocene relative sea-level database for the Baltic Sea
  • 2021
  • Ingår i: Quaternary Science Reviews. - : Elsevier BV. - 0277-3791 .- 1873-457X. ; 266
  • Tidskriftsartikel (refereegranskat)abstract
    • We present a compilation and analysis of 1099 Holocene relative shore-level (RSL) indicators located around the Baltic Sea including 867 relative sea-level data points and 232 data points from the Ancylus Lake and the following transitional phase. The spatial distribution covers the Baltic Sea and near-coastal areas fairly well, but some gaps remain mainly in Sweden. RSL data follow the standardized HOLSEA format and, thus, are ready for spatially comprehensive applications in, e.g., glacial isostatic adjustment (GIA) modelling. We apply a SQL database system to store the nationally provided data sets in their individual form and to map the different input into the HOLSEA format as the information content of the individual data sets from the Baltic Sea area differs. About 80% of the RSL data is related to the last marine stage in Baltic Sea history after 8.5 ka BP (thousand years before present). These samples are grouped according to their dominant RSL tendencies into three clusters: regions with negative, positive and complex (transitional) RSL tendencies. Overall, regions with isostatic uplift driven negative tendencies dominate and show regression in the Baltic Sea basin during the last marine stage. Shifts from positive to negative tendencies in RSL data from transitional regions show a mid-Holocene highstand around 7.5-6.5 ka BP which is consistent with the end of the final melting of the Laurentide Ice Sheet. Comparisons of RSL data with GIA predictions including global ICE-5G and ICE-6G_C ice histories show good fit with RSL data from the regions with negative tendencies, whereas in the transitional areas in the eastern Baltic, predictions for the mid-Holocene clearly overestimate the RSL and fail to recover the midHolocene RSL highstand derived from the proxy reconstructions. These results motivate improvements of ice-sheet and Earth-structure models and show the potential and benefits of the new compilation for future studies. (C) 2021 The Authors. Published by Elsevier Ltd.
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10.
  • Rosiak, D., et al. (författare)
  • Enhanced Quadrupole and Octupole Strength in Doubly Magic Sn 132
  • 2018
  • Ingår i: Physical Review Letters. - 0031-9007. ; 121:25
  • Tidskriftsartikel (refereegranskat)abstract
    • The first 2+ and 3- states of the doubly magic nucleus Sn132 are populated via safe Coulomb excitation employing the recently commissioned HIE-ISOLDE accelerator at CERN in conjunction with the highly efficient MINIBALL array. The Sn132 ions are accelerated to an energy of 5.49 MeV/nucleon and impinged on a Pb206 target. Deexciting γ rays from the low-lying excited states of the target and the projectile are recorded in coincidence with scattered particles. The reduced transition strengths are determined for the transitions 0g.s.+→21+, 0g.s.+→31-, and 21+→31- in Sn132. The results on these states provide crucial information on cross-shell configurations which are determined within large-scale shell-model and Monte Carlo shell-model calculations as well as from random-phase approximation and relativistic random-phase approximation. The locally enhanced B(E2;0g.s.+→21+) strength is consistent with the microscopic description of the structure of the respective states within all theoretical approaches. The presented results of experiment and theory can be considered to be the first direct verification of the sphericity and double magicity of Sn132.
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11.
  • Spagnoletti, P., et al. (författare)
  • Coulomb excitation of Rn 222
  • 2022
  • Ingår i: Physical Review C. - 2469-9985. ; 105:2
  • Tidskriftsartikel (refereegranskat)abstract
    • The nature of quadrupole and octupole collectivity in Rn222 was investigated by determining the electric-quadrupole (E2) and octupole (E3) matrix elements using subbarrier, multistep Coulomb excitation. The radioactive Rn222 beam, accelerated to 4.23 MeV/u, was provided by the HIE-ISOLDE facility at CERN. Data were collected in the Miniball γ-ray spectrometer following the bombardment of two targets, Sn120 and Ni60. Transition E2 matrix elements within the ground-state and octupole bands were measured up to 10ℏ and the results were consistent with a constant intrinsic electric-quadrupole moment, 518(11)efm2. The values of the intrinsic electric-octupole moment for the 0+→3- and 2+→5- transitions were found to be respectively 2360-210+300efm3 and 2300-500+300efm3 while a smaller value, 1200-900+500efm3, was found for the 2+→1- transition. In addition, four excited non-yrast states were identified in this work via γ-γ coincidences.
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12.
  • Stryjczyk, M., et al. (författare)
  • Decay studies of the long-lived states in Tl 186
  • 2020
  • Ingår i: Physical Review C. - 2469-9985. ; 102:2
  • Tidskriftsartikel (refereegranskat)abstract
    • Decay spectroscopy of the long-lived states in Tl186 has been performed at the ISOLDE Decay Station at ISOLDE, CERN. The α decay from the low-spin (2-) state in Tl186 was observed for the first time and a half-life of 3.4-0.4+0.5 s was determined. Based on the α-decay energy, the relative positions of the long-lived states were fixed, with the (2-) state as the ground state, the 7(+) state at 77(56) keV, and the 10(-) state at 451(56) keV. The level scheme of the internal decay of the Tl186(10(-)) state [T1/2=3.40(9) s], which was known to decay solely through emission of 374-keV γ-ray transition, was extended and a lower limit for the β-decay branching bβ>5.9(3)% was determined. The extracted retardation factors for the γ decay of the 10(-) state were compared to the available data in neighboring odd-odd thallium isotopes indicating the importance of the πd3/2 shell in the isomeric decay and significant structure differences between Tl184 and Tl186.
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  • Lennernäs, Hans, et al. (författare)
  • Oral biopharmaceutics tools - Time for a new initiative - An introduction to the IMI project OrBiTo
  • 2014
  • Ingår i: European Journal of Pharmaceutical Sciences. - : Elsevier BV. - 0928-0987 .- 1879-0720. ; 57:SI, s. 292-299
  • Forskningsöversikt (refereegranskat)abstract
    • OrBiTo is a new European project within the IMI programme in the area of oral biopharmaceutics tools that includes world leading scientists from nine European universities, one regulatory agency, one non-profit research organization, four SMEs together with scientists from twelve pharmaceutical companies. The OrBiTo project will address key gaps in our knowledge of gastrointestinal (GI) drug absorption and deliver a framework for rational application of predictive biopharmaceutics tools for oral drug delivery. This will be achieved through novel prospective investigations to define new methodologies as well as refinement of existing tools. Extensive validation of novel and existing biopharmaceutics tools will be performed using active pharmaceutical ingredient (API), formulations and supporting datasets from industry partners. A combination of high quality in vitro or in silico characterizations of API and formulations will be integrated into physiologically based in silica biopharmaceutics models capturing the full complexity of GI drug absorption. This approach gives an unparalleled opportunity to initiate a transformational change in industrial research and development to achieve model-based pharmaceutical product development in accordance with the Quality by Design concept. Benefits include an accelerated and more efficient drug candidate selection, formulation development process, particularly for challenging projects such as low solubility molecules (BCS II and IV), enhanced and modified-release formulations, as well as allowing optimization of clinical product performance for patient benefit. In addition, the tools emerging from OrBiTo are expected to significantly reduce demand for animal experiments in the future as well as reducing the number of human bioequivalence studies required to bridge formulations after manufacturing or composition changes.
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15.
  • Pereira-López, X., et al. (författare)
  • In-beam γ -ray spectroscopy of 94 Ag
  • 2023
  • Ingår i: European Physical Journal A. - : Springer Science and Business Media LLC. - 1434-6001 .- 1434-601X. ; 59:3
  • Tidskriftsartikel (refereegranskat)abstract
    • A recoil-beta-tagging experiment has been performed to study the excited T= 0 and T= 1 states in the odd–odd N= Z nucleus 94Ag, populated via the 40Ca(58Ni,1p3n)94Ag reaction. The experiment was conducted using the MARA recoil separator and JUROGAM3 array at the Accelerator Laboratory of the University of Jyväskylä. Through correlating fast, high-energy beta decays at the MARA focal plane with prompt γ rays emitted at the reaction target, a number of transitions between excited states in 94Ag have been identified. The timing characteristics of these transitions confirm that they fall within decay sequences that feed the short-lived T= 1 ground state of 94Ag. The transitions are proposed to proceed within and between the sets of states with T= 0 and T= 1. Possible correspondence between some of these transitions from analog states in 94Pd has been discussed, and shell-model calculations including multipole and monopole electromagnetic effects have been presented, in order to enable predictions of the decay patterns between the T= 0 and T= 1 states and to allow a theoretical set of Coulomb energy differences to be calculated for the A= 94 T= 1 analog states.
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  • Helmens, Karin F., et al. (författare)
  • Warm summers and rich biotic communities during N-Hemisphere deglaciation
  • 2018
  • Ingår i: Global and Planetary Change. - : Elsevier BV. - 0921-8181 .- 1872-6364. ; 167, s. 61-73
  • Tidskriftsartikel (refereegranskat)abstract
    • Detailed studies on fossil remains of plants or animals in glacial lake sediments are rare. As a result, environmental conditions right at the moment of deglaciation of the large N-Hemisphere ice-sheets remain largely unknown. Here we study three deglacial phases of the Fennoscandian Ice Sheet as a unique, repeated element in a long sediment record preserved at Soldl in northern Finland. We summarize extensive multi-proxy data (diatoms, phytoliths, chironomids, pollen, spores, non-pollen palynomorphs, macrofossils, lithology, loss-on-ignition, C/N) obtained on glacial lake sediments dated to the early Holocene (ca. 10 kyr BP), early MIS 3 (ca. 50 kyr BP) and early MIS 5a (ca. 80 kyr BP). In contrast to the common view of an unproductive ice-marginal environment, our study reconstructs rich ecosystems both in the glacial lake and along the shores with forest on recently deglaciated land. Higher than present-day summer temperatures are reconstructed based on a large variety of aquatic taxa. Rich biota developed due to the insolation-induced postglacial warming and high nutrient levels, the latter resulting from erosion of fresh bedrock and sediment, leaching of surface soils, decay of plant material under shallow water conditions, and sudden decreases in lake volume. Aquatic communities responded quickly to deglaciation and warm summers and reflect boreal conditions, in contrast to the terrestrial ecosystem which responded with some delay probably due to time required for slow soil formation processes. Birch forest is reconstructed upon deglaciation of the large LGM ice-sheet and shrub tundra following the probably faster melting smaller MIS 4 and MIS 5b ice-sheets. Our study shows that glacial lake sediments can provide valuable palaeo-environmental data, that aquatic biota and terrestrial vegetation rapidly accommodated to new environmental conditions during deglaciation, and that glacial lake ecosystems, and the carbon stored in their sediments, should be included in earth system modeling.
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  • Lappalainen, Hanna K., et al. (författare)
  • Pan-Eurasian Experiment (PEEX) : towards a holistic understanding of the feedbacks and interactions in the land-atmosphere-ocean-society continuum in the northern Eurasian region
  • 2016
  • Ingår i: Atmospheric Chemistry And Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 16:22, s. 14421-14461
  • Tidskriftsartikel (refereegranskat)abstract
    • The northern Eurasian regions and Arctic Ocean will very likely undergo substantial changes during the next decades. The Arctic-boreal natural environments play a crucial role in the global climate via albedo change, carbon sources and sinks as well as atmospheric aerosol production from biogenic volatile organic compounds. Furthermore, it is expected that global trade activities, demographic movement, and use of natural resources will be increasing in the Arctic regions. There is a need for a novel research approach, which not only identifies and tackles the relevant multi-disciplinary research questions, but also is able to make a holistic system analysis of the expected feedbacks. In this paper, we introduce the research agenda of the Pan-Eurasian Experiment (PEEX), a multi-scale, multi-disciplinary and international program started in 2012 (https://www.atm.helsinki.fi/peex/). PEEX sets a research approach by which large-scale research topics are investigated from a system perspective and which aims to fill the key gaps in our understanding of the feedbacks and interactions between the land-atmosphereaquatic-society continuum in the northern Eurasian region. We introduce here the state of the art for the key topics in the PEEX research agenda and present the future prospects of the research, which we see relevant in this context.
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  • Seppä, H., et al. (författare)
  • Spatial structure of the 8200 cal yr BP event in northern Europe
  • 2007
  • Ingår i: Climate of the Past. - : Copernicus GmbH. - 1814-9324 .- 1814-9332. ; 3:2, s. 225-236
  • Tidskriftsartikel (refereegranskat)abstract
    • A synthesis of well-dated high-resolution pollen records suggests a spatial structure in the 8200 cal yr BP event in northern Europe. The temperate, thermophilous tree taxa, especially Corylus, Ulmus, and Alnus, decline abruptly between 8300 and 8000 cal yr BP at most sites located south of 61° N, whereas there is no clear change in pollen values at the sites located in the North-European tree-line region. Pollen-based quantitative temperature reconstructions and several other, independent palaeoclimate proxies, such as lacustrine oxygen-isotope records, reflect the same pattern, with no detectable cooling in the sub-arctic region. The observed patterns challenges the general view of the wide-spread occurrence of the 8200 cal yr BP event in the North Atlantic region. An alternative explanation is that the cooling during the 8200 cal yr BP event took place mostly during the winter and spring, and the ecosystems in the south responded sensitively to the cooling during the onset of the growing season. In contrast, in the sub-arctic area, where the vegetation was still dormant and lakes ice-covered, the cold event is not reflected in pollen-based or lake-sediment-based records.
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22.
  • Szczesniak, T., et al. (författare)
  • A Time Resolution Study of a Continuous Crystal Detector for TOF PET
  • 2010
  • Ingår i: IEEE Transactions on Nuclear Science. - 0018-9499 .- 1558-1578. ; 57:1, s. 40-47
  • Tidskriftsartikel (refereegranskat)abstract
    • The majority of current Positron Emission Tomography (PET) systems are based on block-detectors consisting of many scintillating pixels read by a smaller number of photomultipliers (PMTs). An improvement of the time resolution, using a common light readout from a cluster of PMTs, was proposed by Kuhn et al., and tested by us earlier with LSO crystals. This, triggered an idea to design a new PET detector optimized for Time of Flight (TOF) systems, based on continuous crystals. In the present work, we report on optimization of timing with a 20 x 20 x 20 mm(3) LYSO crystal coupled to a 16-channel photomultiplier H8711-200MOD from Hamamatsu. First, measurements were performed of the transit time jitter, the number of photoelectrons and the time resolution using a small 10 x 10 x 5 mm(3) LSO crystal coupled to a H8711-200MOD PMT. Results were compared with data collected from fast timing photomultipliers like Photonis XP1020, XP3060, XP20D0 or Hamamatsu R9800. In the second part of the study, the time resolution measurements and the optimization of the system were made with a continuous LYSO crystal. The final results are discussed in terms of the measured photoelectron number and the requirements for the TOF-PET scanners.
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23.
  • White, MP, et al. (författare)
  • Associations between green/blue spaces and mental health across 18 countries
  • 2021
  • Ingår i: Scientific reports. - : Springer Science and Business Media LLC. - 2045-2322. ; 11:1, s. 8903-
  • Tidskriftsartikel (refereegranskat)abstract
    • Living near, recreating in, and feeling psychologically connected to, the natural world are all associated with better mental health, but many exposure-related questions remain. Using data from an 18-country survey (n = 16,307) we explored associations between multiple measures of mental health (positive well-being, mental distress, depression/anxiety medication use) and: (a) exposures (residential/recreational visits) to different natural settings (green/inland-blue/coastal-blue spaces); and (b) nature connectedness, across season and country. People who lived in greener/coastal neighbourhoods reported higher positive well-being, but this association largely disappeared when recreational visits were controlled for. Frequency of recreational visits to green, inland-blue, and coastal-blue spaces in the last 4 weeks were all positively associated with positive well-being and negatively associated with mental distress. Associations with green space visits were relatively consistent across seasons and countries but associations with blue space visits showed greater heterogeneity. Nature connectedness was also positively associated with positive well-being and negatively associated with mental distress and was, along with green space visits, associated with a lower likelihood of using medication for depression. By contrast inland-blue space visits were associated with a greater likelihood of using anxiety medication. Results highlight the benefits of multi-exposure, multi-response, multi-country studies in exploring complexity in nature-health associations.
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  • Andersson, Sara B. E., et al. (författare)
  • Interlaboratory Validation of Small-Scale Solubility and Dissolution Measurements of Poorly Water-Soluble Drugs
  • 2016
  • Ingår i: Journal of Pharmaceutical Sciences. - : Elsevier BV. - 0022-3549 .- 1520-6017. ; 105:9, s. 2864-2872
  • Tidskriftsartikel (refereegranskat)abstract
    • The purpose of this study was to investigate the interlaboratory variability in determination of apparent solubility (Sapp) and intrinsic dissolution rate (IDR) using a miniaturized dissolution instrument. Three poorly water-soluble compounds were selected as reference compounds and measured at multiple laboratories using the same experimental protocol. Dissolution was studied in fasted-state simulated intestinal fluid and phosphate buffer (pH 6.5). An additional 6 compounds were used for the development of an IDR measurement guide, which was then validated with 5 compounds. The results clearly showed a need for a standardized protocol including both the experimental assay and the data analysis. Standardization at both these levels decreased the interlaboratory variability. The results also illustrated the difficulties in performing disc IDR on poorly water-soluble drugs because the concentrations reached are typically below the limit of detection. The following guidelines were established: for compounds with Sapp > 1 mg/mL, the disc method is recommended. For compounds with Sapp <100 μg/mL, IDR is recommended to be performed using powder dissolution. Compounds in the interval 100 μg/mL to 1 mg/mL can be analyzed with either of these methods.
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26.
  • Becker, Jeroen H, et al. (författare)
  • ST Analysis of the Fetal Electrocardiogram in Intrapartum Fetal Monitoring: A Meta-Analysis.
  • 2012
  • Ingår i: Obstetrics and Gynecology. - 1873-233X. ; 119:1, s. 145-154
  • Forskningsöversikt (refereegranskat)abstract
    • OBJECTIVE:: To compare the effects of ST-waveform analysis in combination with cardiotocography with conventional cardiotocography for intrapartum fetal monitoring. DATA SOURCES:: We searched MEDLINE, Embase, and PubMed for randomized controlled trials (RCTs) evaluating ST-waveform analysis for intrapartum fetal monitoring. METHODS OF STUDY SELECTION:: We identified RCTs that compared ST-waveform analysis and conventional cardiotocography for intrapartum fetal monitoring of singleton pregnancies in cephalic presentation beyond 34 weeks of gestation and evaluating at least one of the following: metabolic acidosis, umbilical cord pH less than 7.15, umbilical cord pH less than 7.10, umbilical cord pH less than 7.05, umbilical cord pH less than 7.00, Apgar scores less than 7 at 5 minutes, admittance to the neonatal intensive care unit, need for intubation, presence of hypoxic ischemic encephalopathy, perinatal death, operative delivery, and number of fetal blood samplings. TABULATION, INTEGRATION, AND RESULTS:: Five RCTs, which included 15,352 patients, met the selection criteria. Random-effects models were used to estimate the combined relative risks (RRs) of ST analysis compared with conventional cardiotocography. Compared with conventional cardiotocography, ST analysis showed a nonsignificant reduction in metabolic acidosis (RR 0.72, 95% confidence interval 0.43-1.19, number needed to treat [NNT] 357). ST analysis significantly reduced the incidence of additional fetal blood sampling (RR 0.59, 95% confidence interval 0.44-0.79, NNT 11), operative vaginal deliveries (RR 0.88, 95% confidence interval 0.80-0.97, NNT 64), and total operative deliveries (RR 0.94, 95% confidence interval 0.89-0.99, NNT 64). For other outcomes, no differences in effect were seen between ST analysis and conventional cardiotocography, or data were not suitable for meta-analysis. CONCLUSION:: The additional use of ST analysis for intrapartum monitoring reduced the incidence of operative vaginal deliveries and the need for fetal blood sampling but did not reduce the incidence of metabolic acidosis at birth.
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27.
  • Bergquist, Magnus, 1960-, et al. (författare)
  • SJIS Mission : Topical areas and research approaches
  • 2018
  • Ingår i: Scandinavian Journal of Information Systems. - Gothenburg : IRIS Association. - 0905-0167 .- 1901-0990. ; 30:2, s. 3-4
  • Tidskriftsartikel (refereegranskat)
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31.
  • Elbasani, E, et al. (författare)
  • Kaposi's Sarcoma-Associated Herpesvirus Reactivation by Targeting of a dCas9-Based Transcription Activator to the ORF50 Promoter
  • 2020
  • Ingår i: Viruses. - : MDPI AG. - 1999-4915. ; 12:9
  • Tidskriftsartikel (refereegranskat)abstract
    • CRISPR activation (CRISPRa) has revealed great potential as a tool to modulate the expression of targeted cellular genes. Here, we successfully applied the CRISPRa system to trigger the Kaposi’s sarcoma-associated herpesvirus (KSHV) reactivation in latently infected cells by selectively activating ORF50 gene directly from the virus genome. We found that a nuclease-deficient Cas9 (dCas9) fused to a destabilization domain (DD) and 12 copies of the VP16 activation domain (VP192) triggered a more efficient KSHV lytic cycle and virus production when guided to two different sites on the ORF50 promoter, instead of only a single site. To our surprise, the virus reactivation induced by binding of the stable DD-dCas9-VP192 on the ORF50 promoter was even more efficient than reactivation induced by ectopic expression of ORF50. This suggests that recruitment of additional transcriptional activators to the ORF50 promoter, in addition to ORF50 itself, are needed for the efficient virus production. Further, we show that CRISPRa can be applied to selectively express the early lytic gene, ORF57, without disturbing the viral latency. Therefore, CRISPRa-based systems can be utilized to facilitate virus–host interaction studies by controlling the expression of not only cellular but also of specific KSHV genes.
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32.
  • Golub, Malgorzata, et al. (författare)
  • Diel, seasonal, and inter-annual variation in carbon dioxide effluxes from lakes and reservoirs
  • 2023
  • Ingår i: Environmental Research Letters. - : IOP Publishing. - 1748-9326. ; 18:3
  • Tidskriftsartikel (refereegranskat)abstract
    • Accounting for temporal changes in carbon dioxide (CO2) effluxes from freshwaters remains a challenge for global and regional carbon budgets. Here, we synthesize 171 site-months of flux measurements of CO2 based on the eddy covariance method from 13 lakes and reservoirs in the Northern Hemisphere, and quantify dynamics at multiple temporal scales. We found pronounced sub-annual variability in CO2 flux at all sites. By accounting for diel variation, only 11% of site-months were net daily sinks of CO2. Annual CO2 emissions had an average of 25% (range 3%-58%) interannual variation. Similar to studies on streams, nighttime emissions regularly exceeded daytime emissions. Biophysical regulations of CO2 flux variability were delineated through mutual information analysis. Sample analysis of CO2 fluxes indicate the importance of continuous measurements. Better characterization of short- and long-term variability is necessary to understand and improve detection of temporal changes of CO2 fluxes in response to natural and anthropogenic drivers. Our results indicate that existing global lake carbon budgets relying primarily on daytime measurements yield underestimates of net emissions.
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35.
  • Henrich, C., et al. (författare)
  • Coulomb excitation of 142Xe
  • 2018
  • Ingår i: Acta Physica Polonica B. - 0587-4254. ; 49:3, s. 529-533
  • Tidskriftsartikel (refereegranskat)abstract
    • The even-even nucleus 142Xe lies north-east of the doubly magic 132Sn on the neutron-rich side of the nuclear chart. In order to gain further information on the octupole collectivity and the evolution of quadrupole collectivity in this region, a "safe" Coulomb excitation experiment was carried out at the new HIE-ISOLDE facility (CERN) at the end of 2016. As the gamma-ray detector the Miniball spectrometer was used. Beam and target nuclei were detected using C-REX, i.e. an array of segmented Si detectors, covering forward as well as backward angles in the laboratory frame.
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36.
  • Horejs, CM, et al. (författare)
  • Preventing tissue fibrosis by local biomaterials interfacing of specific cryptic extracellular matrix information
  • 2017
  • Ingår i: Nature communications. - : Springer Science and Business Media LLC. - 2041-1723. ; 8, s. 15509-
  • Tidskriftsartikel (refereegranskat)abstract
    • Matrix metalloproteinases (MMPs) contribute to the breakdown of tissue structures such as the basement membrane, promoting tissue fibrosis. Here we developed an electrospun membrane biofunctionalized with a fragment of the laminin β1-chain to modulate the expression of MMP2 in this context. We demonstrate that interfacing of the β1-fragment with the mesothelium of the peritoneal membrane via a biomaterial abrogates the release of active MMP2 in response to transforming growth factor β1 and rescues tissue integrity ex vivo and in vivo in a mouse model of peritoneal fibrosis. Importantly, our data demonstrate that the membrane inhibits MMP2 expression. Changes in the expression of epithelial-to-mesenchymal transition (EMT)-related molecules further point towards a contribution of the modulation of EMT. Biomaterial-based presentation of regulatory basement membrane signals directly addresses limitations of current therapeutic approaches by enabling a localized and specific method to counteract MMP2 release applicable to a broad range of therapeutic targets.
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37.
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38.
  • Kasurinen, Ville, et al. (författare)
  • Modeling nonlinear responses of DOC transport in boreal catchments in Sweden
  • 2016
  • Ingår i: Water resources research. - 0043-1397 .- 1944-7973. ; 52:7, s. 4970-4989
  • Tidskriftsartikel (refereegranskat)abstract
    • Stream water dissolved organic carbon (DOC) concentrations display high spatial and temporal variation in boreal catchments. Understanding and predicting these patterns is a challenge with great implications for water quality projections and carbon balance estimates. Although several biogeochemical models have been used to estimate stream water DOC dynamics, model biases common during both rain and snow melt-driven events. The parsimonious DOC-model, K-DOC, with 10 calibrated parameters, uses a nonlinear discharge and catchment water storage relationship including soil temperature dependencies of DOC release and consumption. K-DOC was used to estimate the stream water DOC concentrations over 5 years for eighteen nested boreal catchments having total area of 68 km2 (varying from 0.04 to 67.9 km2). The model successfully simulated DOC concentrations during base flow conditions, as well as, hydrological events in catchments dominated by organic and mineral soils reaching NSEs from 0.46 to 0.76. Our semimechanistic model was parsimonious enough to have all parameters estimated using statistical methods. We did not find any clear differences between forest and mire-dominated catchments that could be explained by soil type or tree species composition. However, parameters controlling slow release and consumption of DOC from soil water behaved differently for small headwater catchments (less than 2 km2) than for those that integrate larger areas of different ecosystem types (10–68 km2). Our results emphasize that it is important to account for nonlinear dependencies of both, soil temperature, and catchment water storage, when simulating DOC dynamics of boreal catchments.
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39.
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40.
  • Lahtinen, M. H., et al. (författare)
  • The impact of thermomechanical pulp fiber modifications on thermoplastic lignin composites
  • 2021
  • Ingår i: Composites Part C: Open Access. - : Elsevier BV. - 2666-6820. ; 6
  • Tidskriftsartikel (refereegranskat)abstract
    • Cellulose and lignin are abundant renewable biopolymers that can be used for the manufacture of new, environmentally friendly materials. The objective of this study was to produce composites of kraft lignin, which were reinforced with cellulosic thermomechanical pulp (TMP) fibers. Furthermore, the fibers were chemically modified resulting in cross-linking or increased hydrophobicity. Ideally, these modifications improve interaction between the components in the composite. The effects of the modifications on the tensile strength and thermal properties of the composites were investigated, and the interactions between components were examined by infrared spectroscopy and scanning electron microscopy. When the fibers were cross-linked with polyethylene glycol diglycidyl ether (PEGDE), the tensile strength properties of the composite were significantly improved. Depending on the amount of PEGDE added, tensile strength was increased by 16–34%, and Young's Modulus by 6–18%, but at the same time the strain at break remained the same. Similarly, by using PEGDE, the amount of free plasticizer (PEG) could be reduced, which also improved the water-resistance of the composite. According to scanning electron microscopy, all chemical treatments improved the compatibility of the fibers with the lignin matrix. However, the increase in compatibility was highest when the fibers were cross-linked with a combination of glyoxal and neopentyl glycol (GL/NPG) or by increasing hydrophobicity through acetylation (AC), although the tensile strength properties were the best in case of cross-linking with PEGDE. 
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44.
  • Ojala, A. E. K., et al. (författare)
  • Ice-sheet scale distribution and morphometry of triangular-shaped hummocks (murtoos): a subglacial landform produced during rapid retreat of the Scandinavian Ice Sheet
  • 2019
  • Ingår i: Annals of Glaciology. - : Cambridge University Press (CUP). - 0260-3055 .- 1727-5644. ; 60:80, s. 115-126
  • Tidskriftsartikel (refereegranskat)abstract
    • High-resolution digital elevation models of Finland and Sweden based on LiDAR (Light Detection and Ranging) reveal subglacial landforms in great detail. We describe the ice-sheet scale distribution and morphometric characteristics of a glacial landform that is distinctive in morphology and occurs commonly in the central parts of the former Scandinavian Ice Sheet, especially up-ice of the Younger Dryas end moraine zone. We refer to these triangular or V-shaped landforms as murtoos (singular, `murtoo'). Murtoos are typically 30-200 m in length and 30-200 m in width with a relief of commonly <5 m. Murtoos have straight and steep edges, a triangular tip oriented parallel to ice-flow direction, and an asymmetric longitudinal profile with a shorter, but steeper down-ice slope. The spatial distribution of murtoos and their geomorphic relation to other landforms indicate that they formed subglacially during times of climate warming and rapid retreat of the Scandinavian Ice Sheet when large amounts of meltwater were delivered to the bed. Murtoos are formed under warm-based ice and may be associated with a non-channelized subglacial hydraulic system that evacuated large discharges of subglacial water.
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45.
  • Ojala, JRM, et al. (författare)
  • A novel scavenger receptor 5-based antibiotic-independent selection method for generation of stable recombinant protein-producing mammalian cell lines especially suitable for proteins affecting cell adhesion
  • 2012
  • Ingår i: BioTechniques. - : Future Science Ltd. - 1940-9818 .- 0736-6205. ; 53:4, s. 221-
  • Tidskriftsartikel (refereegranskat)abstract
    • The establishment of stable recombinant protein-producing mammalian cell lines is an expensive, time-consuming, tedious procedure. In some cases, expressed recombinant proteins have adverse effects on host cell function, including cell adhesion. Based on the adhesive properties of SCARA5, a scavenger receptor (SR) of the class A SR family, we developed a method for selection of stable recombinant protein-producing cell clones that relies on an internal ribosome entry site (IRES) vector where the protein of interest is expressed in the same messenger RNA as SCARA5, resulting in improved adhesion and increased cell viability of recombinant protein-producing cells in serum-free media. This method does not depend on antibiotics, complicated selective cell culture media or equipment, and thus offers the advantages of being inexpensive, environmentally friendly, and simple.
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46.
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47.
  • Ojala, O., et al. (författare)
  • Associations of impulsivity, hyperactivity, and inattention with nonsuicidal self-injury and suicidal behavior: longitudinal cohort study following children at risk for neurodevelopmental disorders into mid-adolescence
  • 2022
  • Ingår i: BMC Psychiatry. - : Springer Science and Business Media LLC. - 1471-244X. ; 22:1
  • Tidskriftsartikel (refereegranskat)abstract
    • Background The knowledge of how the separate Attention-Deficit/Hyperactivity Disorder (ADHD) subdimensions (impulsivity, hyperactivity, and inattention) are associated with nonsuicidal self-injury (NSSI) and suicidal behavior (SB) is limited. The objective of this study was to investigate the associations of childhood ADHD subdimensions with NSSI and SB in children at risk of neurodevelopmental disorders (NDDs; including ADHD). Methods The sample (N = 391) included twin pairs where at least one twin screened positive for at least one NDD or common comorbidity at age 9 or 12. Data on ADHD subdimensions was collected through a telephone interview with a caregiver/legal guardian at age 9 or 12, and data on NSSI and SB was collected through an in-person clinical assessment at age 15. The associations between the ADHD subdimensions and NSSI or SB were tested in three different models: (1) univariable, (2) together with the other ADHD subdimensions, and (3) in a confounder-adjusted model including other NDD symptoms in addition to ADHD subdimensions, for NSSI and SB separately. Results A total of 32 (8.2%) adolescents reported life-time engagement of NSSI, and 18 (4.6%) SB. Childhood impulsivity was associated with SB and childhood inattention with NSSI, in all models. Hyperactivity was not meaningfully associated with any of the outcomes. Conclusion Impulsivity and inattention, but not hyperactivity, may be of particular importance in understanding SB and NSSI. Brief screening for impulsivity and inattention in childhood could facilitate detection of children vulnerable to NSSI and SB and indicate valuable information for preventive and intervention strategies.
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