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Sökning: WFRF:(Hietala A)

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  • Brasseur, Z., et al. (författare)
  • Measurement report: Introduction to the HyICE-2018 campaign for measurements of ice-nucleating particles and instrument inter-comparison in the Hyytiala boreal forest
  • 2022
  • Ingår i: Atmospheric Chemistry and Physics. - : Copernicus GmbH. - 1680-7316 .- 1680-7324. ; 22:8, s. 5117-5145
  • Tidskriftsartikel (refereegranskat)abstract
    • The formation of ice particles in Earth's atmosphere strongly influences the dynamics and optical properties of clouds and their impacts on the climate system. Ice formation in clouds is often triggered heterogeneously by ice-nucleating particles (INPs) that represent a very low number of particles in the atmosphere. To date, many sources of INPs, such as mineral and soil dust, have been investigated and identified in the low and mid latitudes. Although less is known about the sources of ice nucleation at high latitudes, efforts have been made to identify the sources of INPs in the Arctic and boreal environments. In this study, we investigate the INP emission potential from high-latitude boreal forests in the mixed-phase cloud regime. We introduce the HyICE-2018 measurement campaign conducted in the boreal forest of Hyytiala, Finland, between February and June 2018. The campaign utilized the infrastructure of the Station for Measuring Ecosystem-Atmosphere Relations (SMEAR) II, with additional INP instruments, including the Portable Ice Nucleation Chamber I and II (PINC and PINCii), the SPectrometer for Ice Nuclei (SPIN), the Portable Ice Nucleation Experiment (PINE), the Ice Nucleation SpEctrometer of the Karlsruhe Institute of Technology (INSEKT) and the Microlitre Nucleation by Immersed Particle Instrument (mu L-NIPI), used to quantify the INP concentrations and sources in the boreal environment. In this contribution, we describe the measurement infrastructure and operating procedures during HyICE-2018, and we report results from specific time periods where INP instruments were run in parallel for inter-comparison purposes. Our results show that the suite of instruments deployed during HyICE-2018 reports consistent results and therefore lays the foundation for forthcoming results to be considered holistically. In addition, we compare measured INP concentrations to INP parameterizations, and we observe good agreement with the Tobo et al. (2013) parameterization developed from measurements conducted in a ponderosa pine forest ecosystem in Colorado, USA.
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  • Hakkinen, K, et al. (författare)
  • Implementation of CYP2D6 copy-number imputation panel and frequency of key pharmacogenetic variants in Finnish individuals with a psychotic disorder
  • 2022
  • Ingår i: The pharmacogenomics journal. - : Springer Science and Business Media LLC. - 1473-1150 .- 1470-269X. ; 22:3, s. 166-172
  • Tidskriftsartikel (refereegranskat)abstract
    • We demonstrate that CYP2D6 copy-number variation (CNV) can be imputed using existing imputation algorithms. Additionally, we report frequencies of key pharmacogenetic variants in individuals with a psychotic disorder from the genetically bottle-necked population of Finland. We combined GWAS chip and CYP2D6 CNV data from the Breast Cancer Pain Genetics study to construct an imputation panel (n = 902) for CYP2D6 CNV. The resulting data set was used as a CYP2D6 CNV imputation panel in 9262 non-related individuals from the SUPER-Finland study. Based on imputation of 9262 individuals we confirm the higher frequency of CYP2D6 ultrarapid metabolizers and a 22-fold enrichment of the UGT1A1 decreased function variant rs4148323 (UGT1A1*6) in Finland compared with non-Finnish Europeans. Similarly, the NUDT15 variant rs116855232 was highly enriched in Finland. We demonstrate that imputation of CYP2D6 CNV is possible and the methodology enables studying CYP2D6 in large biobanks with genome-wide data.
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  • Hauke, DJ, et al. (författare)
  • Multimodal prognosis of negative symptom severity in individuals at increased risk of developing psychosis
  • 2021
  • Ingår i: Translational psychiatry. - : Springer Science and Business Media LLC. - 2158-3188. ; 11:1, s. 312-
  • Tidskriftsartikel (refereegranskat)abstract
    • Negative symptoms occur frequently in individuals at clinical high risk (CHR) for psychosis and contribute to functional impairments. The aim of this study was to predict negative symptom severity in CHR after 9 months. Predictive models either included baseline negative symptoms measured with the Structured Interview for Psychosis-Risk Syndromes (SIPS-N), whole-brain gyrification, or both to forecast negative symptoms of at least moderate severity in 94 CHR. We also conducted sequential risk stratification to stratify CHR into different risk groups based on the SIPS-N and gyrification model. Additionally, we assessed the models’ ability to predict functional outcomes in CHR and their transdiagnostic generalizability to predict negative symptoms in 96 patients with recent-onset psychosis (ROP) and 97 patients with recent-onset depression (ROD). Baseline SIPS-N and gyrification predicted moderate/severe negative symptoms with significant balanced accuracies of 68 and 62%, while the combined model achieved 73% accuracy. Sequential risk stratification stratified CHR into a high (83%), medium (40–64%), and low (19%) risk group regarding their risk of having moderate/severe negative symptoms at 9 months follow-up. The baseline SIPS-N model was also able to predict social (61%), but not role functioning (59%) at above-chance accuracies, whereas the gyrification model achieved significant accuracies in predicting both social (76%) and role (74%) functioning in CHR. Finally, only the baseline SIPS-N model showed transdiagnostic generalization to ROP (63%). This study delivers a multimodal prognostic model to identify those CHR with a clinically relevant negative symptom severity and functional impairments, potentially requiring further therapeutic consideration.
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  • Piehl, F., et al. (författare)
  • Efficacy and Safety of Rituximab for New-Onset Generalized Myasthenia Gravis The RINOMAX Randomized Clinical Trial
  • 2022
  • Ingår i: Jama Neurology. - : American Medical Association (AMA). - 2168-6149 .- 2168-6157.
  • Tidskriftsartikel (refereegranskat)abstract
    • IMPORTANCE Rituximab is a third-line option for refractory generalized myasthenia gravis (MG) based on empirical evidence, but its effect in new-onset disease is unknown. OBJECTIVE To investigate the efficacy and safety of rituximab compared with placebo as an add-on to standard of care for MG. DESIGN, SETTING, AND PARTICIPANTS This randomized, double-blind, placebo-controlled study took place throughout 48 weeks at 7 regional clinics in Sweden. Key inclusion criteria were age older than 18 years, onset of generalized symptoms within 12 months or less, and a Quantitative Myasthenia Gravis (QMG) score of 6 or more. Patients were screened from October 20, 2016, to March 2, 2020. Key exclusion criteria included pure ocular MG, suspected thymoma, previous thymectomy, and prior noncorticosteroid immunosuppressants or high doses of corticosteroids. INTERVENTIONS Participants were randomized 1:1 without stratification to a single intravenous infusion of 500 mg of rituximab or matching placebo. MAIN OUTCOMES AND MEASURES Minimal disease manifestations at 16 weeks defined as a QMG score of 4 or less with prednisolone, 10 mg or less daily, and no rescue treatment. RESULTS Of 87 potentially eligible patients, 25 were randomized to rituximab (mean [SD] age, 67.4 [13.4] years; 7 [28%] female) and 22 to placebo (mean [SD] age, 58 [18.6] years; 7 [32%] female). Compared with placebo, a greater proportion with rituximab met the primary end point; 71% (17 of 24) in the rituximab group vs 29% (6 of 21) in the placebo group (Fisher exact test P = .007; probability ratio, 2.48 [95% CI, 1.20-5.11]). Secondary end points, comparing changes in Myasthenia Gravis Activities of Daily Living and Myasthenia Gravis Quality of Life at 16 weeks with QMG at 24 weeks did not differ between groups with censoring for rescue treatment (per-protocol analysis) but were in favor of active treatment when rescue treatment was taken into account by worst rank imputation (post hoc analysis). Rescue treatments were also more frequent in the placebo arm (rituximab: 1 [4%]; placebo, 8 [36%]). One patient in the placebo arm had a myocardial infarction with cardiac arrest and 1 patient in the active arm experienced a fatal cardiac event. CONCLUSIONS AND RELEVANCE A single dose of 500 mg of rituximab was associated with greater probability of minimal MG manifestations and reduced need of rescue medications compared with placebo. Further studies are needed to address long-term benefit-risk balance with this treatment.
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  • Telloni, D., et al. (författare)
  • Study of two interacting interplanetary coronal mass ejections encountered by Solar Orbiter during its first perihelion passage Observations and modeling
  • 2021
  • Ingår i: Astronomy and Astrophysics. - : EDP Sciences. - 0004-6361 .- 1432-0746. ; 656
  • Tidskriftsartikel (refereegranskat)abstract
    • Context. Solar Orbiter, the new-generation mission dedicated to solar and heliospheric exploration, was successfully launched on February 10, 2020, 04:03 UTC from Cape Canaveral. During its first perihelion passage in June 2020, two successive interplanetary coronal mass ejections (ICMEs), propagating along the heliospheric current sheet (HCS), impacted the spacecraft.Aims. This paper addresses the investigation of the ICMEs encountered by Solar Orbiter on June 7-8, 2020, from both an observational and a modeling perspective. The aim is to provide a full description of those events, their mutual interaction, and their coupling with the ambient solar wind and the HCS.Methods. Data acquired by the MAG magnetometer, the Energetic Particle Detector suite, and the Radio and Plasma Waves instrument are used to provide information on the ICMEs' magnetic topology configuration, their magnetic connectivity to the Sun, and insights into the heliospheric plasma environment where they travel, respectively. On the modeling side, the Heliospheric Upwind eXtrapolation model, the 3D COronal Rope Ejection technique, and the EUropean Heliospheric FORecasting Information Asset (EUHFORIA) tool are used to complement Solar Orbiter observations of the ambient solar wind and ICMEs, and to simulate the evolution and interaction of the ejecta in the inner heliosphere, respectively.Results. Both data analysis and numerical simulations indicate that the passage of two distinct, dynamically and magnetically interacting (via magnetic reconnection processes) ICMEs at Solar Orbiter is a possible scenario, supported by the numerous similarities between EUHFORIA time series at Solar Orbiter and Solar Orbiter data.Conclusions. The combination of in situ measurements and numerical simulations (together with remote sensing observations of the corona and inner heliosphere) will significantly lead to a deeper understanding of the physical processes occurring during the CME-CME interaction.
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  • Fliri, L., et al. (författare)
  • Solution-state nuclear magnetic resonance spectroscopy of crystalline cellulosic materials using a direct dissolution ionic liquid electrolyte
  • 2023
  • Ingår i: Nature Protocols. - : Springer Nature. - 1754-2189 .- 1750-2799. ; 18, s. 2084-2123
  • Tidskriftsartikel (refereegranskat)abstract
    • Owing to its high sustainable production capacity, cellulose represents a valuable feedstock for the development of more sustainable alternatives to currently used fossil fuel-based materials. Chemical analysis of cellulose remains challenging, and analytical techniques have not advanced as fast as the development of the proposed materials science applications. Crystalline cellulosic materials are insoluble in most solvents, which restricts direct analytical techniques to lower-resolution solid-state spectroscopy, destructive indirect procedures or to ‘old-school’ derivatization protocols. While investigating their use for biomass valorization, tetralkylphosphonium ionic liquids (ILs) exhibited advantageous properties for direct solution-state nuclear magnetic resonance (NMR) analysis of crystalline cellulose. After screening and optimization, the IL tetra-n-butylphosphonium acetate [P4444][OAc], diluted with dimethyl sulfoxide-d 6, was found to be the most promising partly deuterated solvent system for high-resolution solution-state NMR. The solvent system has been used for the measurement of both 1D and 2D experiments for a wide substrate scope, with excellent spectral quality and signal-to-noise, all with modest collection times. The procedure initially describes the scalable syntheses of an IL, in 24–72 h, of sufficient purity, yielding a stock electrolyte solution. The dissolution of cellulosic materials and preparation of NMR samples is presented, with pretreatment, concentration and dissolution time recommendations for different sample types. Also included is a set of recommended 1D and 2D NMR experiments with parameters optimized for an in-depth structural characterization of cellulosic materials. The time required for full characterization varies between a few hours and several days. 
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  • Hietala, M, et al. (författare)
  • DNA-based carrier screening in primary healthcare : screening for aspartylglucosaminuria mutations in maternity health offices
  • 1996
  • Ingår i: Clinical Chemistry. - 0009-9147 .- 1530-8561. ; 42:9, s. 1398-1404
  • Tidskriftsartikel (refereegranskat)abstract
    • Large-scale genetic screening programs are complex enterprises in which ethical, technical, medical, and socioeconomic aspects have to be handled with professional expertise. Establishment of automated, relatively robust, and inexpensive laboratory techniques is one step of this path. Here a pilot carrier-screening program for the mutations causing aspartylglucosaminuria was carried out for pregnant women in primary care maternity health offices. Women (1975) were tested before their 12th week of pregnancy, and 31 heterozygotes were detected. The sampling was based on dried blood strips, facilitating convenient handling and inexpensive mailing to the laboratory. The mutation detection technique, solid-phase mini-sequencing simplified by the use of scintillation microplates and automated equipment, proved to be rapid, simple, inexpensive, and reliable, with a low repeat rate (2.5%). In conclusion, we found that good collaboration between the primary healthcare unit, the laboratory, and counseling experts, combined with modern laboratory technology, facilitate reliable low-cost genetic testing.
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  • Kloprogge, F., et al. (författare)
  • Artemether-lumefantrine dosing for malaria treatment in young children and pregnant women: A pharmacokinetic-pharmacodynamic meta-analysis
  • 2018
  • Ingår i: Plos Medicine. - : Public Library of Science (PLoS). - 1549-1676 .- 1549-1277. ; 15:6
  • Tidskriftsartikel (refereegranskat)abstract
    • Background The fixed dose combination of artemether-lumefantrine (AL) is the most widely used treatment for uncomplicated Plasmodium falciparum malaria. Relatively lower cure rates and lumefantrine levels have been reported in young children and in pregnant women during their second and third trimester. The aim of this study was to investigate the pharmacokinetic and pharmacodynamic properties of lumefantrine and the pharmacokinetic properties of its metabolite, desbutyl-lumefantrine, in order to inform optimal dosing regimens in all patient populations. A search in PubMed, Embase, ClinicalTrials. gov, Google Scholar, conference proceedings, and the WorldWide Antimalarial Resistance Network (WWARN) pharmacology database identified 31 relevant clinical studies published between 1 January 1990 and 31 December 2012, with 4,546 patients in whom lumefantrine concentrations were measured. Under the auspices of WWARN, relevant individual concentration-time data, clinical covariates, and outcome data from 4,122 patients were made available and pooled for the meta-analysis. The developed lumefantrine population pharmacokinetic model was used for dose optimisation through in silico simulations. Venous plasma lumefantrine concentrations 7 days after starting standard AL treatment were 24.2% and 13.4% lower in children weighing < 15 kg and 15-25 kg, respectively, and 20.2% lower in pregnant women compared with non-pregnant adults. Lumefantrine exposure decreased with increasing pre-treatment parasitaemia, and the dose limitation on absorption of lumefantrine was substantial. Simulations using the lumefantrine pharmacokinetic model suggest that, in young children and pregnant women beyond the first trimester, lengthening the dose regimen (twice daily for 5 days) and, to a lesser extent, intensifying the frequency of dosing (3 times daily for 3 days) would be more efficacious than using higher individual doses in the current standard treatment regimen (twice daily for 3 days). The model was developed using venous plasma data from patients receiving intact tablets with fat, and evaluations of alternative dosing regimens were consequently only representative for venous plasma after administration of intact tablets with fat. The absence of artemether-dihydroartemisinin data limited the prediction of parasite killing rates and recrudescent infections. Thus, the suggested optimised dosing schedule was based on the pharmacokinetic endpoint of lumefantrine plasma exposure at day 7. Our findings suggest that revised AL dosing regimens for young children and pregnant women would improve drug exposure but would require longer or more complex schedules. These dosing regimens should be evaluated in prospective clinical studies to determine whether they would improve cure rates, demonstrate adequate safety, and thereby prolong the useful therapeutic life of this valuable antimalarial treatment.
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  • Nyberg, J, et al. (författare)
  • Glucose-dependent insulinotropic polypeptide is expressed in adult hippocampus and induces progenitor cell proliferation
  • 2005
  • Ingår i: The Journal of neuroscience : the official journal of the Society for Neuroscience. - : Society for Neuroscience. - 1529-2401. ; 25:7, s. 1816-1825
  • Tidskriftsartikel (refereegranskat)abstract
    • The hippocampal dentate gyrus (DG) is an area of active proliferation and neurogenesis within the adult brain. The molecular events controlling adult cell genesis in the hippocampus essentially remain unknown. It has been reported previously that adult male and female rats from the strains Sprague Dawley (SD) and spontaneously hypertensive (SHR) have a marked difference in proliferation rates of cells in the hippocampal DG. To exploit this natural variability and identify potential regulators of cell genesis in the hippocampus, hippocampal gene expression from male SHR as well as male and female SD rats was analyzed using a cDNA array strategy. Hippocampal expression of the gene-encoding glucose-dependent insulinotropic polypeptide (GIP) varied strongly in parallel with cell-proliferation rates in the adult rat DG. Moreover, robust GIP immunoreactivity could be detected in the DG. The GIP receptor is expressed by cultured adult hippocampal progenitors and throughout the granule cell layer of the DG, including progenitor cells. Thus, these cells have the ability to respond to GIP. Indeed, exogenously delivered GIP induced proliferation of adult-derived hippocampal progenitorsin vivoas well asin vitro, and adult GIP receptor knock-out mice exhibit a significantly lower number of newborn cells in the hippocampal DG compared with wild-type mice. This investigation demonstrates the presence of GIP in the brain for the first time and provides evidence for a regulatory function for GIP in progenitor cell proliferation.
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  • Sandholm, Niina, et al. (författare)
  • New susceptibility loci associated with kidney disease in type 1 diabetes
  • 2012
  • Ingår i: PLOS Genetics. - San Francisco, USA : Public Library of Science, PLOS. - 1553-7390 .- 1553-7404. ; 8:9, s. e1002921-
  • Tidskriftsartikel (refereegranskat)abstract
    • Diabetic kidney disease, or diabetic nephropathy (DN), is a major complication of diabetes and the leading cause of end-stage renal disease (ESRD) that requires dialysis treatment or kidney transplantation. In addition to the decrease in the quality of life, DN accounts for a large proportion of the excess mortality associated with type 1 diabetes (T1D). Whereas the degree of glycemia plays a pivotal role in DN, a subset of individuals with poorly controlled T1D do not develop DN. Furthermore, strong familial aggregation supports genetic susceptibility to DN. However, the genes and the molecular mechanisms behind the disease remain poorly understood, and current therapeutic strategies rarely result in reversal of DN. In the GEnetics of Nephropathy: an International Effort (GENIE) consortium, we have undertaken a meta-analysis of genomewide association studies (GWAS) of T1D DN comprising similar to 2.4 million single nucleotide polymorphisms (SNPs) imputed in 6,691 individuals. After additional genotyping of 41 top ranked SNPs representing 24 independent signals in 5,873 individuals, combined meta-analysis revealed association of two SNPs with ESRD: rs7583877 in the AFF3 gene (P = 1.2 x 10(-8)) and an intergenic SNP on chromosome 15q26 between the genes RGMA and MCTP2, rs12437854 (P = 2.0 x 10(-9)). Functional data suggest that AFF3 influences renal tubule fibrosis via the transforming growth factor-beta (TGF-beta 1) pathway. The strongest association with DN as a primary phenotype was seen for an intronic SNP in the ERBB4 gene (rs7588550, P = 2.1 x 10(-7)), a gene with type 2 diabetes DN differential expression and in the same intron as a variant with cis-eQTL expression of ERBB4. All these detected associations represent new signals in the pathogenesis of DN.
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  • Collinson, Glyn A., et al. (författare)
  • Shocklets and Short Large Amplitude Magnetic Structures (SLAMS) in the High Mach Foreshock of Venus
  • 2023
  • Ingår i: Geophysical Research Letters. - : American Geophysical Union (AGU). - 0094-8276 .- 1944-8007. ; 50:18
  • Tidskriftsartikel (refereegranskat)abstract
    • Shocklets and short large-amplitude magnetic structures (SLAMS) are steepened magnetic fluctuations commonly found in Earth's upstream foreshock. Here we present Venus Express observations from the 26th of February 2009 establishing their existence in the steady-state foreshock of Venus, building on a past study which found SLAMS during a substantial disturbance of the induced magnetosphere. The Venusian structures were comparable to those reported near Earth. The 2 Shocklets had magnetic compression ratios of 1.23 and 1.34 with linear polarization in the spacecraft frame. The 3 SLAMS had ratios between 3.22 and 4.03, two of which with elliptical polarization in the spacecraft frame. Statistical analysis suggests SLAMS coincide with unusually high solar wind Alfvén mach-number at Venus (12.5, this event). Thus, while we establish Shocklets and SLAMS can form in the stable Venusian foreshock, they may be rarer than at Earth. We estimate a lower limit of their occurrence rate of ≳14%.
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  • Eriksson, Elin, et al. (författare)
  • Strong current sheet at a magnetosheath jet : Kinetic structure and electron acceleration
  • 2016
  • Ingår i: Journal of Geophysical Research - Space Physics. - : American Geophysical Union (AGU). - 2169-9380 .- 2169-9402. ; 121:10, s. 9608-9618
  • Tidskriftsartikel (refereegranskat)abstract
    • Localized kinetic-scale regions of strong current are believed to play an important role in plasma thermalization and particle acceleration in turbulent plasmas. We present a detailed study of a strong localized current, 4900 nA m(-2), located at a fast plasma jet observed in the magnetosheath downstream of a quasi-parallel shock. The thickness of the current region is similar to 3 ion inertial lengths and forms at a boundary separating magnetosheath-like and solar wind-like plasmas. On ion scales the current region has the shape of a sheet with a significant average normal magnetic field component but shows strong variations on smaller scales. The dynamic pressure within the magnetosheath jet is over 3 times the solar wind dynamic pressure. We suggest that the current sheet is forming due to high velocity shears associated with the jet. Inside the current sheet we observe local electron acceleration, producing electron beams, along the magnetic field. However, there is no clear sign of ongoing reconnection. At higher energies, above the beam energy, we observe a loss cone consistent with part of the hot magnetosheath-like electrons escaping into the colder solar wind-like plasma. This suggests that the acceleration process within the current sheet is similar to the one that occurs at shocks, where electron beams and loss cones are also observed. Therefore, electron beams observed in the magnetosheath do not have to originate from the bow shock but can also be generated locally inside the magnetosheath.
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  • Hietala, H., et al. (författare)
  • Supermagnetosonic Jets behind a Collisionless Quasiparallel Shock
  • 2009
  • Ingår i: Physical Review Letters. - 0031-9007 .- 1079-7114. ; 103:24, s. 245001-
  • Tidskriftsartikel (refereegranskat)abstract
    • The downstream region of a collisionless quasiparallel shock is structured containing bulk flows with high kinetic energy density from a previously unidentified source. We present Cluster multispacecraft measurements of this type of supermagnetosonic jet as well as of a weak secondary shock front within the sheath, that allow us to propose the following generation mechanism for the jets: The local curvature variations inherent to quasiparallel shocks can create fast, deflected jets accompanied by density variations in the downstream region. If the speed of the jet is super(magneto)sonic in the reference frame of the obstacle, a second shock front forms in the sheath closer to the obstacle. Our results can be applied to collisionless quasiparallel shocks in many plasma environments.
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  • Hietala, H., et al. (författare)
  • Supermagnetosonic subsolar magnetosheath jets and their effects : from the solar wind to the ionospheric convection
  • 2012
  • Ingår i: Annales Geophysicae. - : Copernicus GmbH. - 0992-7689 .- 1432-0576. ; 30:1, s. 33-48
  • Tidskriftsartikel (refereegranskat)abstract
    • It has recently been proposed that ripples inherent to the bow shock during radial interplanetary magnetic field (IMF) may produce local high speed flows in the magnetosheath. These jets can have a dynamic pressure much larger than the dynamic pressure of the solar wind. On 17 March 2007, several jets of this type were observed by the Cluster spacecraft. We study in detail these jets and their effects on the magnetopause, the magnetosphere, and the ionospheric convection. We find that (1) the jets could have a scale size of up to a few RE but less than similar to 6 R-E transverse to the XGSE axis; (2) the jets caused significant local magnetopause perturbations due to their high dynamic pressure; (3) during the period when the jets were observed, irregular pulsations at the geostationary orbit and localised flow enhancements in the ionosphere were detected. We suggest that these inner magnetospheric phenomena were caused by the magnetosheath jets.
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  • Hietala, M., et al. (författare)
  • Moisture stability and mechanical durability of peat biocomposites
  • 2017
  • Ingår i: ICCM21 Proceedings. - : ICCM, International Committee on Composite Materials.
  • Konferensbidrag (refereegranskat)abstract
    • Peat, the organic matter formed from incomplete degradation of vegetation in peatlands, was studied as lignocellulosic raw material in manufacture of biocomposites. Peat mosses with varying degree of decomposition, namely slightly decomposed peat (H2) and moderately decomposed peat (H6), were ground into different particle size fractions which were used to prepare peat-polypropylene (PP) composites with 50 wt% peat content using extrusion compounding. The moisture absorption and dimensional stability as well as the mechanical properties and microstructure before and after cyclic freeze-thaw conditioning of the peat-PP composites were analysed and compared to reference wood-plastic composite (WPC). The mechanical properties of peat-PP composites were better than the properties of reference WPC before the freeze-thaw conditioning, and the mechanical permanence of peat-PP composites was better after the cyclic conditioning. Especially when peat with higher decomposition degree was used (H6), the mechanical permanence of peat-PP composites was improved. Likewise, the moisture absorption and the dimensional stability properties were improved the more decomposed the used peat was. The particle size did not affect the composite properties as much as the decomposition degree of peat, though the dimensional stability of peat-PP composite with moderately decomposed peat was better with smaller particle size peat.
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  • Hietala, Riikka, et al. (författare)
  • A note on the deep-water inflow to the Bothnian Sea
  • 2007
  • Ingår i: Journal of marine systems. - : Elsevier BV. - 0924-7963. ; 68:1-2, s. 255-264
  • Tidskriftsartikel (refereegranskat)abstract
    • The deepest connection between the Bothnian Sea and the Baltic Proper is the narrow Understen-Märket trench with a threshold depth of around 90 m. The deep-water flow through this passage, which is of great importance for the hydrographic state of the entire Gulf of Bothnia, was surveyed by the R/V Aranda in October 2004. On the basis of these field results as well as climatological data, it has been concluded that the deep-water flow can be described using a hydraulic framework applied to a channel of parabolic cross-section. The Understen-Märket trench is sufficiently narrow to, in principle, permits neglect of the Coriolis force. Since it may prove useful for other systems, the study, however, also includes the analysis and evaluation of a scheme to determine rotational first-order corrections to controlled transports predicted using standard non-rotating hydraulic theory.
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  • Hirvonen, J, et al. (författare)
  • Measurement of striatal and extrastriatal dopamine transporter binding with high-resolution PET and [11C]PE2I: quantitative modeling and test-retest reproducibility
  • 2008
  • Ingår i: Journal of cerebral blood flow and metabolism : official journal of the International Society of Cerebral Blood Flow and Metabolism. - : SAGE Publications. - 0271-678X. ; 28:5, s. 1059-1069
  • Tidskriftsartikel (refereegranskat)abstract
    • [11C]PE2I is a novel positron emission tomography (PET) radiotracer for the dopamine transporter (DAT). The reproducibility and reliability of [11C]PE2I measurements, especially in the small DAT-rich brain regions, is unknown and of critical importance to the interpretation of the data. Five healthy volunteers were scanned twice during the same day using [11C]PE2I and the HRRT PET scanner. Methods based on metabolite-corrected arterial plasma curve and reference region were used to estimate distribution volumes ( VT) and binding potential ( BP). Within-subject and between-subject variabilities were compared. [11C]PE2I accumulated in the DAT-rich striatum and the midbrain. Equilibrium of specific binding appeared late in the striatum, whereas it was reached earlier in the midbrain. Plasma metabolite analysis showed that the potentially brain-penetrant 4-hydroxymethyl metabolite represented 15% to 20% of total plasma radioactivity. VT and BP measurements were associated with low within-subject variability. Measurement of DAT binding in small brain regions, including the substantia nigra, is reproducible and reliable using [11C]PE2I and high-resolution research tomograph. A scanning time of more than 70 mins is required for the striatum, while less is sufficient for DAT quantification in the midbrain. The previously suggested involvement of the potentially brain-penetrant radioactive metabolite in the quantification should be further studied.
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  • Kurko, TAT, et al. (författare)
  • Long-term use of benzodiazepines: Definitions, prevalence and usage patterns - a systematic review of register-based studies
  • 2015
  • Ingår i: European psychiatry : the journal of the Association of European Psychiatrists. - : Cambridge University Press (CUP). - 1778-3585. ; 30:8, s. 1037-1047
  • Tidskriftsartikel (refereegranskat)abstract
    • BackgroundNumerous treatment guidelines recommend that long-term use of benzodiazepines (BZD) should be avoided primarily due to development of tolerance and a risk for BZD dependence. Despite this, long-term BZD use remains a controversial subject in clinical patient care with “for and against” debates. However, there is no explicit understanding of what is meant by long-term BZD use in real world. The aim of this study was to assess different definitions, usage patterns, prevalence and other characteristics of long-term BZD use based on published register-based studies. Synthesis of these characteristics is essential to derive a meaningful definition of long-term BZD.MethodsSystematic review of register-based studies on long-term BZD use published in 1994–2014.ResultsFourty-one studies met our predetermined inclusion criteria. The length of BZD use defined as “long-term” varied in these studies ranging from one month to several years. The most common definition was six months or longer during a year. The prevalence of long-term BZD use in the general population was estimated to be about 3%. The relative proportion of long-term BZD users (all definitions) in adult BZD users ranged from 6% to 76% (mean 24%; 95% CL 13–36%). The estimates were higher in studies only on the elderly (47%; 95% CL 31–64%). Long-term use involved typically steady treatment with low BZD doses. However, in elderly patients long-term BZD use and exceeding recommended doses was relatively common. Several characteristics associated with long-term use were found.ConclusionsLong-term BZD use is common and a clinical reality. Uniform definitions for “long-term”, which is in line with population-based evidence, is needed to have more comparable results between studies. Our systematic review suggests that duration of BZD treatment over six months, the most common definition for long-term BZD use in the included studies. As also recommended previously, it is a useful starting point for further analyses on disadvantages but also potential advantages associated with long-term BZD use.
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44.
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45.
  • 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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46.
  • Norrman, AE, et al. (författare)
  • Salivary Biomarkers and Oral Health in Liver Transplant Recipients, with an Emphasis on Diabetes
  • 2021
  • Ingår i: Diagnostics (Basel, Switzerland). - : MDPI AG. - 2075-4418. ; 11:4
  • Tidskriftsartikel (refereegranskat)abstract
    • Salivary biomarkers have been linked to various systemic diseases. We examined the association between salivary biomarkers, periodontal health, and microbial burden in liver transplant (LT) recipients with and without diabetes, after transplantation. We hypothesized that diabetic recipients would exhibit impaired parameters. This study included 84 adults who received an LT between 2000 and 2006 in Finland. Dental treatment preceded transplantation. The recipients were re-examined, on average, six years later. We evaluated a battery of salivary biomarkers, microbiota, and subjective oral symptoms. Periodontal health was assessed, and immunosuppressive treatments were recorded. Recipients with impaired periodontal health showed higher matrix metalloproteinase-8 (MMP-8) levels (p < 0.05) and MMP-8/tissue inhibitor of matrix metalloproteinase 1 (TIMP1) ratios (p < 0.001) than recipients with good periodontal health. Diabetes post-LT was associated with impaired periodontal health (p < 0.05). No difference between groups was found in the microbial counts. Salivary biomarker levels did not seem to be affected by diabetes. However, the advanced pro-inflammatory state induced by and associated with periodontal inflammation was reflected in the salivary biomarker levels, especially MMP-8 and the MMP-8/TIMP-1 molar ratio. Thus, these salivary biomarkers may be useful for monitoring the oral inflammatory state and the course of LT recipients.
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47.
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48.
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49.
  • Rahpeymai, Yalda, 1977, et al. (författare)
  • Complement: a novel factor in basal and ischemia-induced neurogenesis.
  • 2006
  • Ingår i: The EMBO journal. - : Wiley. - 0261-4189 .- 1460-2075. ; 25:6, s. 1364-74
  • Tidskriftsartikel (refereegranskat)abstract
    • Through its involvement in inflammation, opsonization, and cytolysis, the complement protects against infectious agents. Although most of the complement proteins are synthesized in the central nervous system (CNS), the role of the complement system in the normal or ischemic CNS remains unclear. Here we demonstrate for the first time that neural progenitor cells and immature neurons express receptors for complement fragments C3a and C5a (C3a receptor (C3aR) and C5a receptor). Mice that are deficient in complement factor C3 (C3(-/-)) lack C3a and are unable to generate C5a through proteolytic cleavage of C5 by C5-convertase. Intriguingly, basal neurogenesis is decreased both in C3(-/-) mice and in mice lacking C3aR or mice treated with a C3aR antagonist. The C3(-/-) mice had impaired ischemia-induced neurogenesis both in the subventricular zone, the main source of neural progenitor cells in adult brain, and in the ischemic region, despite normal proliferative response and larger infarct volumes. Thus, in the adult mammalian CNS, complement activation products promote both basal and ischemia-induced neurogenesis.
  •  
50.
  • Riklund, Katrine, et al. (författare)
  • A putative mechanism for the non-specific uptake of intact radiolabelled monoclonal antibodies in the testes and prostate.
  • 1996
  • Ingår i: Acta Oncologica. - 0284-186X .- 1651-226X. ; 35:3, s. 303-307
  • Tidskriftsartikel (refereegranskat)abstract
    • Non-specific testicular accumulation of radiolabelled intact anti-CEA monoclonal antibody (MAb), (A431/26, Behringwerke AG) was observed in 11 out of 12 patients with the testes and prostate included in the examination field at radioimmunoscintigraphy (RIS). Previous studies have shown that placental alkaline phosphatase (PLAP) serves as an Fc-receptor, mediating IgG transport through the placenta. A closely related protein, the germ cell alkaline phosphatase (GCAP), is expressed in the testes. The testicular uptake of IgG is observed only when intact but not fragmented MAbs are used, indicating involvement of Fc-receptors. MDCK cells (dog kidney cell line) transfected with the plasmid pSVT7 containing the GCAP gene were shown to acquire the capacity to both express membrane bound GCAP and to bind IgG on the cell surface. This might indicate that GCAP is responsible for the non-specific accumulation of intact MAb in the testes and prostate often observed when intact murine MAbs are used for radioimmunolocalization (RIL).
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