| 1. |
- Alehagen, Urban, et al.
(författare)
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Effects of an Intervention with Selenium and Coenzyme Q(10) on Five Selected Age-Related Biomarkers in Elderly Swedes Low in Selenium: Results That Point to an Anti-Ageing Effect-A Sub-Analysis of a Previous Prospective Double-Blind Placebo-Controlled Randomised Clinical Trial
- 2023
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Ingår i: Cells. - : MDPI. - 2073-4409. ; 12:13
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Tidskriftsartikel (refereegranskat)abstract
- Background: Ageing is associated with cardiovascular disease (CVD). As no single biomarker reflects the full ageing process, we aimed to investigate five CVD- and age-related markers and the effects of selenium and coenzyme Q10 intervention to elucidate the mechanisms that may influence the course of ageing. Methods: This is a sub-study of a previous prospective double-blind placebo-controlled randomized clinical trial that included 441 subjects low in selenium (mean age 77, 49% women). The active treatment group (n = 220) received 200 & mu;g/day of selenium and 200 mg/day of coenzyme Q10, combined. Blood samples were collected at inclusion and after 48 months for measurements of the intercellular adhesion molecule (ICAM-1), adiponectin, leptin, stem cell factor (SCF) and osteoprotegerin (OPG), using ELISAs. Repeated measures of variance and ANCOVA evaluations were used to compare the two groups. In order to better understand and reduce the complexity of the relationship between the biomarkers and age, factor analyses and structural equation modelling (SEM) were performed, and a structural model is presented. Results: Correlation analyses of biomarker values at inclusion in relation to age, and relevant markers related to inflammation, endothelial dysfunction and fibrosis, demonstrated the biomarkers association with these pathological processes; however, only ICAM1 and adiponectin were directly correlated with age. SEM analyses showed, however, that the biomarkers ICAM-1, adiponectin, SCF and OPG, but not leptin, all had significant associations with age and formed two independent structural factors, both significantly related to age. While no difference was observed at inclusion, the biomarkers were differently changed in the active treatment and placebo groups (decreasing and increasing levels, respectively) at 48 months (p & LE; 0.02 in all, adjusted), and in the SEM model, they showed an anti-ageing impact. Conclusions: Supplementation with selenium/Q10 influenced the analysed biomarkers in ways indicating an anti-ageing effect, and by applying SEM methodology, the interrelationships between two independent structural factors and age were validated.
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| 2. |
- Alehagen, Urban, 1951-, et al.
(författare)
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Improved cardiovascular health by supplementation with selenium and coenzyme Q10 : applying structural equation modelling (SEM) to clinical outcomes and biomarkers to explore underlying mechanisms in a prospective randomized double-blind placebo-controlled intervention project in Sweden
- 2022
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Ingår i: European Journal of Nutrition. - : Springer Heidelberg. - 1436-6207 .- 1436-6215. ; 61:6, s. 3135-3148
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Tidskriftsartikel (refereegranskat)abstract
- Purpose Selenium and coenzyme Q10 have synergistic antioxidant functions. In a four-year supplemental trial in elderly Swedes with a low selenium status, we found improved cardiac function, less cardiac wall tension and reduced cardiovascular mortality up to 12 years of follow-up. Here we briefly review the main results, including those from studies on biomarkers related to cardiovascular risk that were subsequently conducted. In an effort, to explain underlying mechanisms, we conducted a structured analysis of the inter-relationship between biomarkers. Methods Selenium yeast (200 mu g/day) and coenzyme Q10 (200 mg/ day), or placebo was given to 443 elderly community-living persons, for 48 months. Structural Equation Modelling (SEM) was used to investigate the statistical inter-relationships between biomarkers related to inflammation, oxidative stress, insulin-like growth factor 1, expression of microRNA, fibrosis, and endothelial dysfunction and their impact on the clinical effects. The main study was registered at Clinicaltrials.gov at 30th of September 2011, and has the identifier NCT01443780. Results In addition to positive clinical effects, the intervention with selenium and coenzyme Q10 was also associated with favourable effects on biomarkers of cardiovascular risk. Using these results in the SEM model, we showed that the weights of the first-order factors inflammation and oxidative stress were high, together forming a second-order factor inflammation/oxidative stress influencing the factors, fibrosis (beta = 0.74; p < 0.001) and myocardium (beta = 0.65; p < 0.001). According to the model, the intervention impacted fibrosis and myocardium through these factors, resulting in improved cardiac function and reduced CV mortality. Conclusion Selenium reduced inflammation and oxidative stress. According to the SEM analysis, these effects reduced fibrosis and improved myocardial function pointing to the importance of supplementation in those low on selenium and coenzyme Q10.
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| 3. |
- Andersson, Stefan, FK, bibliotekarie, 1959-, et al.
(författare)
-
DiVA : 20 år av unikt samarbete
- 2021
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Ingår i: Uppsala universitetsbibliotek 1621–2021. - Uppsala : Acta Universitatis Upsaliensis. ; , s. 59-66
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Bokkapitel (populärvet., debatt m.m.)
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| 4. |
- Arnelo, Urban, et al.
(författare)
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Intraoperative pancreatoscopy can improve the detection of skip lesions during surgery for intraductal papillary mucinous neoplasia : a pilot study
- 2023
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Ingår i: Pancreatology (Print). - : Elsevier. - 1424-3903 .- 1424-3911. ; 23:6, s. 704-711
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Tidskriftsartikel (refereegranskat)abstract
- Objectives: Intraoperative pancreatoscopy is a promising procedure that might guide surgical resection for suspected main duct (MD) and mixed type (MT) intraductal papillary mucinous neoplasms (IPMNs). The aim of the present study was to assess the diagnostic yield and clinical impact of intraoperative pancreatoscopy in patients operated on for MD and MT-IPMNs.Methods: This is a retrospective cohort study. Patients undergoing surgery for suspected MD or MT-IPMN underwent intraoperative pancreatoscopy and frozen section analysis. In all patients who required extended resection due to pancreatoscopic findings, we compared the final histology with the results of the intraoperative frozen section analysis.Results: In total, 46 patients, 48% females, mean age (range) 67 years (45–82 years) underwent intraoperative pancreatoscopy. No mortality or procedure related complications were observed. Pancreatoscopy changed the operative course in 30 patients (65%), leading to extended resections in 20 patients (43%) and to parenchyma sparing procedures in 10 patients (22%). Analyzing the group of patients who underwent extended resections, 7 (35%) displayed lesions that needed further surgical treatment (six high grade dysplasia and one with G1 pancreatic neuroendocrine tumor) and among those 7, just 1 (14%) would have been detected exclusively with histological frozen section analysis of the transection margin. The combination of both pancreatoscopy and frozen section analysis lead to 86% sensitivity and 92% specificity for the detection of pathological tissue in the remnant pancreas.Conclusion: Intraoperative pancreatoscopy is a safe and feasible procedure and might allow the detection of skip lesions during surgery for suspect MD-involving IPMNs.
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| 5. |
- Felton, Adam, et al.
(författare)
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Correction to: Keeping pace with forestry : Multi-scale conservation in a changing production forest matrix (vol 49, pg 1050, 2020)
- 2020
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Ingår i: Ambio. - : Springer. - 0044-7447 .- 1654-7209. ; 49:5, s. 1065-1066
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Tidskriftsartikel (refereegranskat)abstract
- In the original published article, the sentence “Nevertheless, semi-natural forest remnants continue to be harvested and fragmented (Svensson et al. 2018; Jonsson et al. 2019), and over 2000 forest-associated species (of 15 000 assessed) are listed as threatened on Sweden’s red-list, largely represented by macro-fungi, beetles, lichens and butterflies (Sandström 2015).”under the section Introduction was incorrect. The correct version of the sentence is “Nevertheless, semi-natural forest remnants continue to be harvested and fragmented (Svensson et al. 2018; Jonsson et al. 2019), and approximately 2000 forest-associated species (of 15 000 assessed) are on Sweden’s red-list, largely represented by macro-fungi, beetles, lichens and butterflies (Sandström 2015).”
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| 6. |
- Felton, Adam, et al.
(författare)
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Keeping pace with forestry : Multi-scale conservation in a changing production forest matrix
- 2020
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Ingår i: Ambio. - : Springer. - 0044-7447 .- 1654-7209. ; 49:5, s. 1050-1064
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Tidskriftsartikel (refereegranskat)abstract
- The multi-scale approach to conserving forest biodiversity has been used in Sweden since the 1980s, a period defined by increased reserve area and conservation actions within production forests. However, two thousand forest-associated species remain on Sweden's red-list, and Sweden's 2020 goals for sustainable forests are not being met. We argue that ongoing changes in the production forest matrix require more consideration, and that multi-scale conservation must be adapted to, and integrated with, production forest development. To make this case, we summarize trends in habitat provision by Sweden's protected and production forests, and the variety of ways silviculture can affect biodiversity. We discuss how different forestry trajectories affect the type and extent of conservation approaches needed to secure biodiversity, and suggest leverage points for aiding the adoption of diversified silviculture. Sweden's long-term experience with multi-scale conservation and intensive forestry provides insights for other countries trying to conserve species within production landscapes.
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| 7. |
- Lundqvist, Jennie Mari, et al.
(författare)
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A Phenomenographic Analysis Of Students’ Experience Of Geological Time
- 2021
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Ingår i: Journal of Astronomy & Earth Sciences Education (JAESE). - : Clute Institute. - 2374-6254 .- 2374-6246. ; 8:1, s. 1-26
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Tidskriftsartikel (refereegranskat)abstract
- Geological time is by many geoscience instructors considered a threshold concept for geoscience students, being acentral concept for how we experience geosceince phenomena that takes place on a spatio-temporal scale rangingfrom micro (e.g. cloud formation) to macro (e.g. plate tectonics). If one wishes to understand geoscience phenomenathat goes beyond human perception, one must move from the concrete toward the abstract—from experiencing aphenomenon with one’s senses toward an experience of the phenomenon that is based on an mind construct; we referto such competency as disciplinary spatio-temporal competency (DSTC). The purpose of this study is to gain anunderstanding of how first-year students in a geoscience program in Sweden experience and represent thephenomenon of geological time, i.e. to capture their DSTC. Analyazing data from three semi-structured groupinterviews using a phenomenographic approach revealed how the students express geological time through theirlanguage, their gestures, and their visualizations. From the result in this study, including four qualitatively differentthemes, or categories of description, it is possible to conclude that the students' way of expressing geological timegive rise to exciting interpretations and we believe that these expressions can provide information also about howstudents experience (and learn about) geological time. We report that through students’ illustrations and discussions,students experience geological time as something more than a static one-dimensional straight line. The data analysisshows that students connect geological time with spatio-temporal aspects from various geosientific phenomena, oneexample of such an dynamic description of geological time is “One simply fills it with more information” indicatingthat the students experience geological time as two-dimensional (space and time).
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| 8. |
- Nota, Kevin, 1993-, et al.
(författare)
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Norway spruce postglacial recolonization of Fennoscandia
- 2022
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Ingår i: Nature Communications. - : Nature Publishing Group. - 2041-1723. ; 13:1
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Tidskriftsartikel (refereegranskat)abstract
- Contrasting theories exist regarding how Norway spruce (Picea abies) recolonized Fennoscandia after the last glaciation and both early Holocene establishments from western microrefugia and late Holocene colonization from the east have been postulated. Here, we show that Norway spruce was present in southern Fennoscandia as early as 14.7 ± 0.1 cal. kyr BP and that the millennia-old clonal spruce trees present today in central Sweden likely arrived with an early Holocene migration from the east. Our findings are based on ancient sedimentary DNA from multiple European sites (N = 15) combined with nuclear and mitochondrial DNA analysis of ancient clonal (N = 135) and contemporary spruce forest trees (N = 129) from central Sweden. Our other findings imply that Norway spruce was present shortly after deglaciation at the margins of the Scandinavian Ice Sheet, and support previously disputed finds of pollen in southern Sweden claiming spruce establishment during the Lateglacial.
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| 9. |
- Pietilä, Riikka, et al.
(författare)
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Molecular anatomy of adult mouse leptomeninges
- 2023
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Ingår i: Neuron. - : Elsevier. - 0896-6273 .- 1097-4199. ; 111:23
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Tidskriftsartikel (refereegranskat)abstract
- Leptomeninges, consisting of the pia mater and arachnoid, form a connective tissue investment and barrier enclosure of the brain. The exact nature of leptomeningeal cells has long been debated. In this study, we iden-tify five molecularly distinct fibroblast-like transcriptomes in cerebral leptomeninges; link them to anatomically distinct cell types of the pia, inner arachnoid, outer arachnoid barrier, and dural border layer; and contrast them to a sixth fibroblast-like transcriptome present in the choroid plexus and median eminence. Newly identified transcriptional markers enabled molecular characterization of cell types responsible for adherence of arach-noid layers to one another and for the arachnoid barrier. These markers also proved useful in identifying the molecular features of leptomeningeal development, injury, and repair that were preserved or changed after traumatic brain injury. Together, the findings highlight the value of identifying fibroblast transcriptional subsets and their cellular locations toward advancing the understanding of leptomeningeal physiology and pathology.
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| 10. |
- Simonsson, Johan, et al.
(författare)
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Worse patient-reported outcomes and higher risk of reoperation and adverse events after total hip replacement in patients with opioid use in the year before surgery: a Swedish register-based study on 80,483 patients
- 2022
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Ingår i: Acta Orthopaedica. - : Medical Journals Sweden AB. - 1745-3682 .- 1745-3674. ; 93, s. 190-197
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Tidskriftsartikel (refereegranskat)abstract
- Background and purpose - Recent studies indicate that preoperative use of opioids could be associated with higher rates of complications and worse patient-reported outcomes (PROs) after orthopedic surgery. We investigated the prevalence of preoperative opioid use and analyzed its influence on risk of revision, adverse events (AE), and PROs in patients with total hip replacement (THR). Patients and methods - This observational study included 80,483 patients operated on in 2008-2016 with THRs due to osteoarthritis. Data was obtained from the Swedish Hip Arthroplasty Register, Statistics Sweden's sociodemographic registers, the Swedish National Patient Register, and the Prescribed Drug Register. We focused on patients with ≥ 4 opioid prescriptions filled 1 year prior to THR. To control for confounding, we used propensity scores to weight subjects in our analyses. Logistic and linear regression was used for outcome variables with adjustments for sociodemographic variables and comorbidities. Results - Patients with ≥ 4 opioid prescriptions in the year before THR (n = 14,720 [18%]) had a higher risk of revision within 2 years (1.8% vs. 1.1% OR 1.4, 95% CI 1.3-1.6) and AE within 90 days (9.4% vs. 6.4% OR 1.2, 95% CI 1.2-1.3) compared with patients without opioid treatment in the preoperative period. Patients with ≥ 4 opioid prescriptions rated 5 points worse on a 0-100 scale of Pain Visual Analogue Scale (VAS) and 9 points worse on a general health (EQ) VAS 1 year postoperatively. Interpretation - Having ≥ 4 opioid prescriptions filled in the year before surgery is associated with a higher risk of revision, adverse events, and worse PROs after THR. Consequently, preoperative opioid treatment should be addressed in the clinical assessment of patients eligible for THR.
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| 11. |
- Soler, Josep M., et al.
(författare)
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Predictive and Inverse Modeling of a Radionuclide Diffusion Experiment in Crystalline Rock at ONKALO (Finland)
- 2023
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Ingår i: Nuclear Technology. - : Informa UK Limited. - 0029-5450 .- 1943-7471. ; 209:11, s. 1765-1784
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Tidskriftsartikel (refereegranskat)abstract
- The REPRO-TDE test was performed at a depth of about 400 m in the ONKALO underground research facility in Finland. Synthetic groundwater containing radionuclide tracers [tritiated water tracer (HTO), 36Cl, 22Na, 133Ba, and 134Cs] was circulated for about 4 years in a packed-off interval of the injection borehole. Tracer activities were additionally monitored in two observation boreholes. The test was the subject of a modeling exercise by the SKB GroundWater Flow and Transport of Solutes Task Force. Eleven teams participated in the exercise, using different model concepts and approaches. Predictive model calculations were based on laboratory-based information concerning porosities, diffusion coefficients, and sorption partition coefficients. After the experimental results were made available, the teams were able to revise their models to reproduce the observations. General conclusions from these back-analysis calculations include the need for reduced effective diffusion coefficients for 36Cl compared to those applicable to HTO (anion exclusion), the need to implement weaker sorption for 22Na compared to results from laboratory batch sorption experiments, and the observation of large differences between the theoretical initial concentrations for the strongly sorbing 133Ba and 134Cs, and the first measured values a few hours after tracer injection. Different teams applied different concepts, concerning mainly the implementation of isotropic versus anisotropic diffusion, or the possible existence of borehole disturbed zones around the different boreholes. The role of microstructure was also addressed in two of the models.
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| 12. |
- Soler, Josep, et al.
(författare)
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Modelling of the LTDE-SD radionuclide diffusion experiment in crystalline rock at the Aspo Hard Rock Laboratory (Sweden)
- 2022
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Ingår i: Geologica Acta. - : Universitat Autònoma de Barcelona. - 1695-6133 .- 1696-5728. ; 20, s. 1-32
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Tidskriftsartikel (refereegranskat)abstract
- This study shows a comparison and analysis of results from a modelling exercise concerning a field experiment involving the transport and retention of different radionuclide tracers in crystalline rock. This exercise was performed within the Swedish Nuclear Fuel and Waste Management Company (SKB) Task Force on Modelling of Groundwater Flow and Transport of Solutes (Task Force GWFTS). Task 9B of the Task Force GWFTS was the second subtask within Task 9 and focused on the modelling of experimental results from the Long Term Sorption Diffusion Experiment in situ tracer test. The test had been performed at a depth of about 410m in the Aspo Hard Rock Laboratory. Synthetic groundwater containing a cocktail of radionuclide tracers was circulated for 198 days on the natural surface of a fracture and in a narrow slim hole drilled in unaltered rock matrix. Overcoring of the rock after the end of the test allowed for the measurement of tracer distribution profiles in the rock from the fracture surface (A cores) and also from the slim hole (D cores). The measured tracer activities in the rock samples showed long profiles (several cm) for non-or weakly-sorbing tracers (Cl-36, Na-22), but also for many of the more strongly-sorbing radionuclides. The understanding of this unexpected feature was one of the main motivations for this modelling exercise. However, re-evaluation and revision of the data during the course of Task 9B provided evidence that the anomalous long tails at low activities for strongly sorbing tracers were artefacts due to cross-contamination during rock sample preparation. A few data points remained for Cs-137, Ba-133, Ni-63 and Cd-109, but most measurements at long distances from the tracer source (>10mm) were now below the reported detection limits. Ten different modelling teams provided results for this exercise, using different concepts and codes. The tracers that were finally considered were Na-22, Cl-36, Co-57, Ni-63, Ba-133, Cs-137, Cd-109, Ra-226 and Np-237. Three main types of models were used: i) analytical solutions to the transport-retention equations, ii) continuum -porous-medium numerical models, and iii) microstructure-based models accounting for small-scale heterogeneity (i.e. mineral grains, porosities and/or microfracture distributions) and potential centimetre-scale fractures. The modelling by the different teams led to some important conclusions, concerning for instance the presence of a disturbed zone (a few mm in thickness) next to the fracture surface and to the wall of the slim hole and the role of micro-fractures and cm-scale fractures in the transport of weakly sorbing tracers. These conclusions could be reached after the re-evaluation and revision of the experimental data (tracer profiles in the rock) and the analysis of the different sets of model results provided by the different teams.
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| 13. |
- Svensson, Carl, 1974-, et al.
(författare)
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Early and repeated nutrient additions support far greater stemwood production in Norway spruce than traditional late-rotation fertilisation
- 2023
-
Ingår i: Forest Ecology and Management. - : Elsevier. - 0378-1127 .- 1872-7042. ; 549
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Tidskriftsartikel (refereegranskat)abstract
- Silvicultural techniques aimed at promoting forest biomass production can help meet the growing demand for renewable materials and mitigate climate change. One-time nitrogen (N) addition late in the rotation is a well-established method to stimulate growth in coniferous forests in northern Europe, but the potential gains from earlier and repeated fertiliser application remain uncertain. Here, we tested the impact of repeated fertilisation in juvenile Norway spruce stands across 9 sites covering a wide range of growing conditions over a 700 km stretch from central to southern Sweden. We tested the fertilisation effects using two separate studies: i) an interval trial with a fertilisation frequency of one (F1), two (F2), or three years (F3) performed at plot-level across five sites (2002–2014), and ii) a practice-oriented trial with a two-year fertilisation interval (F2) applied at stand-level and replicated at four sites (2003–2013). The composition of the nutrient mix in each plot was optimised based on foliar nutrient analyses. In the interval trial, all three fertilisation schedules strongly increased periodic annual increment (PAI) (F1: 105 %, F2: 93 %, F3: 79 %) relative to the unfertilised control, resulting in more than a doubling of stem volume yield in the F1 and F2 treatments (120 % and 110 %, respectively) and a significantly smaller but still sizeable yield stimulation of 82 % in the F3 treatment. Nitrogen use efficiency (NUE, stemwood volume increase per unit mass of N added) was similar among fertilisation intervals (on average 130 m3 ha−1 1000 kg N−1), indicating that the extra N provided through yearly fertilisation (F1) is redundant given the similar stemwood yields in the F2 treatment. In the practice-oriented trial, the sole F2 treatment increased PAI by 95 % over the control, translating into a yield stimulation of 114 % and an almost identical NUE to that of the interval trial. NUE greatly exceeded the figures typically observed with traditional late-rotation fertilisation and correlated inversely with baseline site productivity (using site index as a proxy) in the F1 and F2 treatments (the latter pooled across the two trials). Our results clearly indicate that nutrient limitation restricts growth and carbon (C) capture in young Norway spruce plantations in northern Europe to less than half of their potential, highlighting repeated fertilisation at nutrient-poor sites as an effective management tool to support a growing bioeconomy and enhance C sequestration.
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| 14. |
- Svensson, Kim, et al.
(författare)
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Active and passive transductions—definitions and implications for learning
- 2022
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Ingår i: European Journal of Physics. - : IOP Publishing. - 1361-6404 .- 0143-0807. ; 43:2, s. 025705-025705
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Tidskriftsartikel (refereegranskat)abstract
- To move between different semiotic systems, such as graphs and formulas, is a necessary step in learning physics or solving problems. In social semiotics, this movement of semiotic material is called a transduction and during a transduction a student must unpack, filter, and highlight different aspects of the concept or problem. Unpacking, filtering, and highlighting have been shown to be important to the meaning-making process and transductions should be seen as indicators of meaning-making and learning. However, in this paper we argue that not all transductions performed by students requires unpacking, filtering, or highlighting, and hence the definition of transduction needs to be refined in its description. We introduce the ideas of passive and active transductions that separates transductions that may lead to meaning-making from transductions that may not. This separation is done through shown engagement with the semiotic material of the transduction. We connect shown engagement with the semiotic material to the already established anatomy of disciplinary discernment to create a useful tool when evaluating student engagement and discernment. In the paper, we showcase examples of passive and active transductions and provide a short description of how to identify them in different learning situations.
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| 15. |
- Svensson, Kim, et al.
(författare)
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Concept of a transductive link
- 2020
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Ingår i: Physical Review Physics Education Research. - 2469-9896. ; 16:2
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Tidskriftsartikel (refereegranskat)abstract
- This theoretical paper defines and explores the concepts of transductive links and transductive chains, as part of the theoretical framework of social semiotics. Social semiotics stems from the multimodal framework, which provides a theoretical perspective, constructs, and a language to describe a shift of semiotic material within or between semiotic systems, such as rewriting a text or moving from a function to a plot. Within this framework a shift of semiotic material between two such systems is referred to as a transduction. This paper aims to expand on the concept of transduction by identifying a theoretical contribution to the modeling of this process, referred to as a transductive link. This link is suggested to affect the transduction process and the resulting learning experience. For example, when plotting measurement data, a computer program can be employed to read the data and to transform the data into pixel information. In this case, programming, or the act of programming, acts as a link between the two resources in the transduction process - a transductive link. In other cases, multiple transductions can be performed one after another resulting in these links creating what we define as a transductive chain. By observing and analyzing the use of different semiotic systems in different learning situations, transductive links and chains can be identified and examined. From this identification one has the possibility to find weak links in the transductive chain and address them accordingly. As such, we suggest that transductive links and chains are powerful tools to be able to understand students' learning experiences.
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| 16. |
- Svensson, Kim, et al.
(författare)
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Programming and its affordances for physics education: A social semiotic and variation theory approach to learning physics
- 2020
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Ingår i: Physical Review Physics Education Research. - 2469-9896. ; 16:1
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Tidskriftsartikel (refereegranskat)abstract
- The paper describes a theoretical analysis of programming and what it offers in terms of the meaning-making process. It finds that programming provide opportunity to iterate, to visualise and to perform transductions. Each affordance has been shown to affect the meaning-making process and can enhance it if used in a meaningful way. By using variation theory as a lens of these affordances, we identify that the different affordances, provided by programming, can be used to great effect in a learning environment and showcases some excerpts from an earlier study that shows this.
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| 17. |
- Svensson, Kim, et al.
(författare)
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Programming as a semiotic system to support physics students' construction of meaning: A pilot study
- 2020
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Ingår i: International Conference on Physics Education (ICPE) 2018. - : IOP Publishing. - 1742-6596. ; 1512
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Konferensbidrag (refereegranskat)abstract
- The paper describes a pilot study where programming was introduced to a small group of Swedish upper secondary students with the intent to showcase how programming could be used to construct meaning about different physics concepts. The study found that the students realized the potential of programming as a tool to investigate and explore physics. The results were then described using the theoretical frameworks of social semiotics and variation theory.
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| 18. |
- Wei, C. T., et al.
(författare)
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Cryptic species in a colorful genus: Integrative taxonomy of the bush robins (Aves, Muscicapidae, Tarsiger) suggests two overlooked species
- 2022
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Ingår i: Molecular Phylogenetics and Evolution. - : Elsevier BV. - 1055-7903 .- 1095-9513. ; 175
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Tidskriftsartikel (refereegranskat)abstract
- Several cryptic avian species have been validated by recent integrative taxonomic efforts in the Sino-Himalayan mountains, indicating that avian diversity in this global biodiversity hotspot may be underestimated. In the present study, we investigated species limits in the genus Tarsiger, the bush robins, a group of montane forest specialists with high species richness in the Sino-Himalayan region. Based on comprehensive sampling of all 11 subspecies of the six currently recognized species, we applied an integrative taxonomic approach by combining multilocus, acoustic, plumage and morphometric analyses. Our results reveal that the isolated north-central Chinese populations of Tarsiger cyanurus, described as the subspecies albocoeruleus but usually considered invalid, is distinctive in genetics and vocalisation, but only marginally differentiated in morphology. We also found the Taiwan endemic T. indicus formosanus to be distinctive in genetics, song and morphology from T. i. indicus and T. i. yunnanensis of the Sino-Himalayan mountains. Moreover, Bayesian species delimitation using BPP suggests that both albocoeruleus and formosanus merit full species status. We propose their treatment as 'Qilian Bluetail' T. albocoeruleus and 'Taiwan Bush Robin' T. formosanus, respectively.
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