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Berg, B., Lönn, M., Ni, X., Sun, T., Dong, L., Gaitnieks, T., . . . Johansson, M.-B. (2022). Decomposition rates in late stages of Scots pine and Norway spruce needle litter: Influence of nutrients and substrate properties over a climate gradient. Forest Ecology and Management, 522, Article ID 120452.
Open this publication in new window or tab >>Decomposition rates in late stages of Scots pine and Norway spruce needle litter: Influence of nutrients and substrate properties over a climate gradient
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2022 (English)In: Forest Ecology and Management, ISSN 0378-1127, E-ISSN 1872-7042, Vol. 522, article id 120452Article in journal (Refereed) Published
Abstract [en]

The aim of this paper is to show different patterns for decomposition of the main mass of needle litter from two boreal and temperate coniferous tree species, both leading to a stabilized fraction of litter. To this purpose we have reviewed information on decomposition patterns in the lignin-dominated (late) stages of two local foliar litter types, namely those of Scots pine (Pinus silvestris) and Norway spruce (Picea abies) from two climatic gradients of equal extension. We have also reviewed factors determining the limit values for both species.

Long-term decomposition studies were used to calculate annual mass loss in the lignin-dominated decomposition stage and relate these to mean annual temperature (MAT), mean annual precipitation (MAP) and concentrations of nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg), manganese (Mn) and acid unhydrolyzable residue (gravimetric lignin, AUR).

There was no effect of MAT on decomposition of either needle litter type. MAP had a rate-dampening effect on decomposition of Norway spruce litter. There was a rate-stimulating effect of Mn for Norway spruce litter but not for that of Scots pine. In spite of the strong negative effect of AUR and N on decomposition of Scots pine litter there was none at all for that of Norway spruce.

Limit values for decomposition were related to the litters’ initial concentrations of N, Mn and AUR and differed between litter types for locally collected, natural litter and for that from experimental litter, the latter having higher N and lower Mn concentrations than the natural litter.

We conclude that the two litter types have clear differences as regards rate- regulating factors for decomposition in the late lignin-dominated stage as well as for the stable fraction and suggest two different pathways for their decomposition. This is the first time that different pathways have been suggested for decomposing litter.

Place, publisher, year, edition, pages
Elsevier, 2022
Keywords
Plant litter decomposition, Acid unhydrolyzable residue, Annual mass loss, Limit values, Substrate nutrients, Climate gradient
National Category
Biological Sciences
Identifiers
urn:nbn:se:hig:diva-39876 (URN)10.1016/j.foreco.2022.120452 (DOI)000843362700006 ()2-s2.0-85136146817 (Scopus ID)
Available from: 2022-09-02 Created: 2022-09-02 Last updated: 2022-12-05Bibliographically approved
Berg, B. & Lönn, M. (2022). Long-term effects of climate and litter chemistry on rates and stable fractions of decomposing Scots pine and Norway spruce needle litter - A synthesis. Forests, 13(1), Article ID 125.
Open this publication in new window or tab >>Long-term effects of climate and litter chemistry on rates and stable fractions of decomposing Scots pine and Norway spruce needle litter - A synthesis
2022 (English)In: Forests, ISSN 1999-4907, E-ISSN 1999-4907, Vol. 13, no 1, article id 125Article in journal (Refereed) Published
Abstract [en]

We have reviewed information on early-, late- and limit-value decomposition stages for litter of Norway spruce (Picea abies) and Scots pine (Pinus silvestris). This synthesis covers c 16 studies/papers made along a climatic gradient; range in mean annual temperature (MAT) from −1 to +7 °C and mean annual precipitation (MAP) from 425 to 1070 mm. Scots pine has an early stage dominated by carbohydrate decomposition and a late stage dominated by decomposition of lignin; Norway spruce has just one stage dominated by lignin decomposition. We used data for annual mass loss to identify rate-regulating factors in both stages; climate data, namely, MAT and MAP, as well as substrate properties, namely, nitrogen (N), acid unhydrolyzable residue (AUR), manganese (Mn). Early-stage decomposition for Scots pine litter was dominated positively by MAT; the late stage was dominated negatively by MAT, N, and AUR, changing with decomposition stage; there was no effect of Mn. Norway spruce litter had no early stage; decomposition in the lignin-dominated stage was mainly negative to MAP, a negative relationship to AUR and non-significant relationships to N and MAT. Mn had a positive relationship. Limit values for decomposition, namely, the accumulated mass loss at which decomposition is calculated to be zero, were related positively to Mn and AUR for Scots pine litter and negatively to AUR for Norway spruce litter. With different sets of rate-regulating factors as well as different compounds/elements related to the limit values, the decomposition patterns or pathways are different.

Place, publisher, year, edition, pages
MDPI, 2022
Keywords
decomposition; acid unhydrolyzable residue; manganese; nitrogen; plant litter; limit values; annual mass loss; mean annual temperature; mean annual precipitation
National Category
Biological Sciences
Identifiers
urn:nbn:se:hig:diva-37771 (URN)10.3390/f13010125 (DOI)000747156500001 ()2-s2.0-85123028299 (Scopus ID)
Available from: 2022-01-31 Created: 2022-01-31 Last updated: 2022-11-01Bibliographically approved
Carpio, A. J., García, M., Hillström, L., Lönn, M., Carvalho, J., Acevedo, P. & Bueno, C. G. (2022). Wild boar effects on fungal abundance and guilds from sporocarp sampling in a boreal forest ecosystem. Animals, 12(19), Article ID 2521.
Open this publication in new window or tab >>Wild boar effects on fungal abundance and guilds from sporocarp sampling in a boreal forest ecosystem
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2022 (English)In: Animals, E-ISSN 2076-2615, Vol. 12, no 19, article id 2521Article in journal (Refereed) Published
Abstract [en]

Native wild boar (Sus scrofa) populations are expanding across Europe. This is cause for concern in some areas where overabundant populations impact natural ecosystems and adjacent agronomic systems. To better manage the potential for impacts, managers require more information about how the species may affect other organisms. For example, information regarding the effect of wild boar on soil fungi for management application is lacking. Soil fungi play a fundamental role in ecosystems, driving essential ecological functions; acting as mycorrhizal symbionts, sustaining plant nutrition and providing defense; as saprotrophs, regulating the organic matter decomposition; or as plant pathogens, regulating plant fitness and survival. During autumn (Sep–Nov) 2018, we investigated the effects of wild boar (presence/absence and rooting intensity) on the abundance (number of individuals) of fungal sporocarps and their functional guilds (symbiotic, saprotrophic and pathogenic). We selected eleven forested sites (400–500 × 150–200 m) in central Sweden; six with and five without the presence of wild boar. Within each forest, we selected one transect (200 m long), and five plots (2 × 2 m each) for sites without wild boar, and ten plots for sites with boars (five within and five outside wild boar disturbances), to determine the relationship between the intensity of rooting and the abundance of sporocarps for three fungal guilds. We found that the presence of wild boar and rooting intensity were associated with the abundance of sporocarps. Interestingly, this relationship varied depending on the fungal guild analyzed, where wild boar rooting had a positive correlation with saprophytic sporocarps and a negative correlation with symbiotic sporocarps. Pathogenic fungi, in turn, were more abundant in undisturbed plots (no rooting) but located in areas with the presence of wild boar. Our results indicate that wild boar activities can potentially regulate the abundance of fungal sporocarps, with different impacts on fungal guilds. Therefore, wild boar can affect many essential ecosystem functions driven by soil fungi in boreal forests, such as positive effects on energy rotation and in creating mineral availability to plants, which could lead to increased diversity of plants in boreal forests.

Place, publisher, year, edition, pages
MDPI, 2022
Keywords
disturbance; ectomycorrhiza; fungal guilds; rooting; Sus scrofa; Sweden; wild boar
National Category
Biological Sciences
Identifiers
urn:nbn:se:hig:diva-40272 (URN)10.3390/ani12192521 (DOI)000866615500001 ()36230261 (PubMedID)2-s2.0-85139783060 (Scopus ID)
Available from: 2022-10-17 Created: 2022-10-17 Last updated: 2024-01-17Bibliographically approved
Berg, B., Sun, T., Johansson, M.-B., Sanborn, P., Ni, X. & Lönn, M. (2021). Magnesium dynamics in decomposing foliar litter - a synthesis. Geoderma, 382, Article ID 114756.
Open this publication in new window or tab >>Magnesium dynamics in decomposing foliar litter - a synthesis
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2021 (English)In: Geoderma, ISSN 0016-7061, E-ISSN 1872-6259, Vol. 382, article id 114756Article in journal (Refereed) Published
Abstract [en]

We synthesized available data for magnesium (Mg) dynamics in newly shed and decomposing foliar litter of mainly pine (Pinus) species, Norway spruce (Picea abies), and birch (Betula) species. Using original, measured data from 40 stands organized in climatic gradients we intended to determine patterns of Mg concentration and net release vs accumulated mass loss of the litter. This synthesis is likely the first synthesis of Mg dynamics in decomposing litter.

In paired stands, litter of both Norway spruce and lodgepole pine (Pinus contorta) had higher Mg concentrations than Scots pine (Pinus silvestris), with concentrations in Norway spruce litter even twice as high.

In decomposing litter, Mg concentrations followed a quadratic (X2-X) function vs accumulated mass loss and consequently had minima, different for Norway spruce and Scots pine litter. Out of 68 decomposition studies 53 gave minimum concentration. The Mg minimum concentration during decomposition was positively related to initial Mg concentration for Scots pine and Scots pine plus lodgepole pine but not for Norway spruce. The increase in concentration suggests that after the minimum Mg was temporarily limiting.

For Norway spruce litter there was a relationship between minimum concentration of Mg and the limit value. There was no such relationship for Scots pine and not for the combined pine data.

Magnesium net release started directly after the incubation and was linear to accumulated mass loss of litter, giving a slope coefficient (release rate) for each study. The net release rate was linear to initial Mg concentration and all studies combined gave a negative linear relationship.

Place, publisher, year, edition, pages
Elsevier, 2021
Keywords
Litter, Decomposition, Magnesium, Mg dynamics, Mg release, Accumulated mass loss
National Category
Biological Sciences
Identifiers
urn:nbn:se:hig:diva-30878 (URN)10.1016/j.geoderma.2020.114756 (DOI)000590747200021 ()2-s2.0-85093957591 (Scopus ID)
Available from: 2019-11-04 Created: 2019-11-04 Last updated: 2022-11-01Bibliographically approved
Ivarsson, L. N., Andren, T., Moros, M., Andersen, T. J., Lönn, M. & Andren, E. (2019). Baltic Sea Coastal Eutrophication in a Thousand Year Perspective. Frontiers in Environmental Science, 7, Article ID 88.
Open this publication in new window or tab >>Baltic Sea Coastal Eutrophication in a Thousand Year Perspective
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2019 (English)In: Frontiers in Environmental Science, E-ISSN 2296-665X, Vol. 7, article id 88Article in journal (Refereed) Published
Abstract [en]

Sediment cores from three sites along the east-coast of Sweden, north-western Baltic Proper, have been studied with respect to lithologies, geochemistry, and diatom assemblages to trace and date early human impact with emphasis on nutrient discharge. The three sites Braviken, Himmerfjarden, and Adfjarden, have been impacted to various degree during the last millennia by multiple stressors like excessive nutrient discharge and hazardous substances, leading to coastal hypoxia, eutrophication, and pollution. These stressors are mainly caused by drivers in the drainage area as increased human population, changed land use, and point sources as industries and a sewage treatment plant. Even though their detailed history differs, the results show similar general patterns for all three sites. We find no evidence in our data from the coastal zone supporting the hypothesis that the extensive areal distribution of hypoxia in the open Baltic Sea during the Medieval Climate Anomaly was caused by human impact. Timing of the onset of man-made eutrophication, as identified from delta N-15 and changes in diatom composition, differs between the three sites, reflecting the site specific geography and local environmental histories of these areas. The onset of eutrophication dates to similar to 1800 CE in Braviken and Himmerfjarden areas, and to similar to 1900 CE in the less urban area of Adfjarden. We conclude that the recorded environmental changes during the last centuries are unique in a thousand year perspective.

Place, publisher, year, edition, pages
FRONTIERS MEDIA SA, 2019
Keywords
diatom stratigraphy, stable nitrogen isotopes, hypoxia, Medieval Climate Anomaly, NW Baltic proper, nutrient discharge
National Category
Biological Sciences
Identifiers
urn:nbn:se:hig:diva-31064 (URN)10.3389/fenvs.2019.00088 (DOI)000471701600001 ()2-s2.0-85068480167 (Scopus ID)
Available from: 2019-11-25 Created: 2019-11-25 Last updated: 2022-11-01Bibliographically approved
Larsson, J., Lind, E. E., Corell, H., Grahn, M., Smolarz, K. & Lönn, M. (2017). Regional genetic differentiation in the blue mussel from the Baltic Sea area. Estuarine, Coastal and Shelf Science, 195, 98-109
Open this publication in new window or tab >>Regional genetic differentiation in the blue mussel from the Baltic Sea area
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2017 (English)In: Estuarine, Coastal and Shelf Science, ISSN 0272-7714, E-ISSN 1096-0015, Vol. 195, p. 98-109Article in journal (Refereed) Published
Abstract [en]

Connectivity plays an important role in shaping the genetic structure and in evolution of local adaptation. In the marine environment barriers to gene flow are in most cases caused by gradients in environmental factors, ocean circulation and/or larval behavior. Despite the long pelagic larval stages, with high potential for dispersal many marine organisms have been shown to have a fine scale genetic structuring. In this study, by using a combination of high-resolution genetic markers, species hybridization data and biophysical modeling we can present a comprehensive picture of the evolutionary landscape for a keystone species in the Baltic Sea, the blue mussel. We identified distinct genetic differentiation between the West Coast, Baltic Proper and Bothnian Sea regions, with lower gene diversity in the Bothnian Sea. Oceanographic connectivity together with salinity and to some extent species identity provides explanations for the genetic differentiation between the West Coast and the Baltic Sea (Baltic Proper and Bothnian Sea). The genetic differentiation between the Baltic Proper and Bothnian Sea cannot be directly explained by oceanographic connectivity, species identity or salinity, while the lower connectivity to the Bothnian Sea may explain the lower gene diversity. © 2016.

Keywords
AFLP, Baltic Sea, Barrier, Gene flow, Oceanographic connectivity, Population genetics
National Category
Environmental Sciences
Research subject
Environmental Studies; Baltic and East European studies
Identifiers
urn:nbn:se:hig:diva-23380 (URN)10.1016/j.ecss.2016.06.016 (DOI)1328/42/2010 (Local ID)1328/42/2010 (Archive number)1328/42/2010 (OAI)
Projects
Evolutionary adaptation to environmental disturbance in marine ecosystems: genetic ecotoxicology in the Baltic Sea
Funder
The Foundation for Baltic and East European Studies, A063-10
Available from: 2016-07-20 Created: 2017-01-27 Last updated: 2019-08-26Bibliographically approved
Mutvei, A., Lönn, M. & Mattsson, J.-E. (2016). Observation not only perception but also cognition. In: Conference proceedings: New perspectives in science education : 5th conference edition : Florence, Italy, 17-18 March 2016. Paper presented at New perspectives in science education, 5th ed, Florence,Italy, March 17-18, 2016. (pp. 365-369). Padova: Libreria Universitaria
Open this publication in new window or tab >>Observation not only perception but also cognition
2016 (English)In: Conference proceedings: New perspectives in science education : 5th conference edition : Florence, Italy, 17-18 March 2016, Padova: Libreria Universitaria , 2016, p. 365-369Conference paper, Published paper (Refereed)
Abstract [en]

According to the Swedish curriculum for primary school it is important in science subjects to develop skills to observe, to describe the observations and to put them into a theoretical framework already starting year 1–3.

Thus, it may be important for the teacher not only to be accustomed to the methods of observing but also to be an expert on using these observations in order to design teaching situations where these skills may be developed.

Here we present a study where 25 pre-service primary school teacher students at the beginning of a 20 weeks course established a relation to a study site focused on ecological questions. The task during the first week of that course was to observe and describe two habitats in the field and suggest what abiotic and biotic factors that had shaped the variation focussing at competition as an important ecological factor. In order to connect those ecological aspects with evolutionary aspects, specimen of the common species in the two habitats were collected and brought to the lab where the students constructed phenetic trees based on morphology but also on ecologically relevant properties like roots/no roots, expecting the set-up to awake evolutionary reflection. A main goal with this week was to give the students tools to investigate nature – to observe and describe patterns and to explain them by observing abiotic and biotic variation and evolutionary features and limitations.

Later during the course we created other, often not obviously similar, situations where the students had the opportunity to use the experiences of this first training week. We used open questions for reflections and examinations in order to get written material to assess the development of the skills.

We found notable personal development in most students and a greater awareness about the importance of personal cognitive activities in order to create better understanding and ability to use achieved knowledge in different situations.

Place, publisher, year, edition, pages
Padova: Libreria Universitaria, 2016
National Category
Learning
Identifiers
urn:nbn:se:hig:diva-23382 (URN)978-88-6292-705-5 (ISBN)
Conference
New perspectives in science education, 5th ed, Florence,Italy, March 17-18, 2016.
Available from: 2017-01-15 Created: 2017-01-27 Last updated: 2018-03-13Bibliographically approved
Larsson, J., Lönn, M., Lind, E. E., Świeżak, J., Smolarz, K. & Grahn, M. (2016). Sewage treatment plant associated genetic differentiation in the blue mussel from the Baltic Sea and Swedish west coast. PeerJ, 4, Article ID e2628.
Open this publication in new window or tab >>Sewage treatment plant associated genetic differentiation in the blue mussel from the Baltic Sea and Swedish west coast
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2016 (English)In: PeerJ, E-ISSN 2167-8359, Vol. 4, article id e2628Article in journal (Refereed) Published
Abstract [en]

Human-derived environmental pollutants and nutrients that reach the aquatic environment through sewage effluents, agricultural and industrial processes are constantly contributing to environmental changes that serve as drivers for adaptive responses and evolutionary changes in many taxa. In this study, we examined how two types of point sources of aquatic environmental pollution, harbors and sewage treatment plants, affect gene diversity and genetic differentiation in the blue mussel in the Baltic Sea area and off the Swedish west coast (Skagerrak). Reference sites (REF) were geographically paired with sites from sewage treatments plant (STP) and harbors (HAR) with a nested sampling scheme, and genetic differentiation was evaluated using a high-resolution marker amplified fragment length polymorphism (AFLP). This study showed that genetic composition in the Baltic Sea blue mussel was associated with exposure to sewage treatment plant effluents. In addition, mussel populations from harbors were genetically divergent, in contrast to the sewage treatment plant populations, suggesting that there is an effect of pollution from harbors but that the direction is divergent and site specific, while the pollution effect from sewage treatment plants on the genetic composition of blue mussel populations acts in the same direction in the investigated sites.

National Category
Biological Sciences Environmental Sciences
Research subject
Baltic and East European studies
Identifiers
urn:nbn:se:hig:diva-23381 (URN)10.7717/peerj.2628 (DOI)000387168200015 ()27812424 (PubMedID)2-s2.0-84994409132 (Scopus ID)
Funder
The Foundation for Baltic and East European Studies, A063-10]
Available from: 2016-11-11 Created: 2017-01-27 Last updated: 2023-08-28Bibliographically approved
Prentice, H. C., Li, Y., Lönn, M., Tunlid, A. & Ghatnekar, L. (2015). A horizontally transferred nuclear gene is associated with microhabitat variation in a natural plant population. Proceedings of the Royal Society of London. Biological Sciences, 282(1821), Article ID 20152453.
Open this publication in new window or tab >>A horizontally transferred nuclear gene is associated with microhabitat variation in a natural plant population
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2015 (English)In: Proceedings of the Royal Society of London. Biological Sciences, ISSN 0962-8452, E-ISSN 1471-2954, Vol. 282, no 1821, article id 20152453Article in journal (Refereed) Published
Abstract [en]

Horizontal gene transfer involves the non-sexual interspecific transmission of genetic material. Even if they are initially functional, horizontally transferred genes are expected to deteriorate into non-expressed pseudogenes, unless they become adaptively relevant in the recipient organism. However, little is known about the distributions of natural transgenes within wild species or the adaptive significance of natural transgenes within wild populations. Here, we examine the distribution of a natural plant-to-plant nuclear transgene in relation to environmental variation within a wild population. Festuca ovina is polymorphic for an extra (second) expressed copy of the nuclear gene (PgiC) encoding cytosolic phosphoglucose isomerase, with the extra PgiC locus having been acquired horizontally from the distantly related grass genus Poa. We investigated variation at PgiC in samples of F. ovina from a fine-scale, repeating patchwork of grassland microhabitats, replicated within spatially separated sites. Even after accounting for spatial effects, the distributions of F. ovina individuals carrying the additional PgiC locus, and one of the enzyme products encoded by the locus, are significantly associated with fine-scale habitat variation. Our results suggest that the PgiC transgene contributes, together with the unlinked 'native' PgiC locus, to local adaptation to a fine-scale mosaic of edaphic and biotic grassland microhabitats.

National Category
Evolutionary Biology
Identifiers
urn:nbn:se:hig:diva-23383 (URN)10.1098/rspb.2015.2453 (DOI)000368096900028 ()26674953 (PubMedID)
Available from: 2015-12-19 Created: 2017-01-27 Last updated: 2021-06-21Bibliographically approved
Lönn, M., Mutvei, A. & Mattsson, J.-E. (2015). Results and Comparison of Different Complementary Assessment Methods of Science Learning Outcome. In: Conference proceedings. New perspectives in science education, 4th ed.: . Paper presented at New perspectives in science education, 4th ed, Florence, March 20-21, 2015.. Libreria universitaria
Open this publication in new window or tab >>Results and Comparison of Different Complementary Assessment Methods of Science Learning Outcome
2015 (English)In: Conference proceedings. New perspectives in science education, 4th ed., Libreria universitaria , 2015Conference paper, Published paper (Refereed)
Abstract [en]

To assess the quality of different aspects of the learning outcomes in relation to knowledge requirements as results of teaching several assessment methods have to be used. For most teachers it is also obvious that students differ in their ability to demonstrate the learning outcome depending on the assessment method used. In order to compare different assessment methods of the learning outcome of pre-school teacher students’ different types of tasks were evaluated and compared in order to identify the potential of each method to give the students fair chances of showing their skills. Thus, assessments based on multiple choice questionnaires of different types, long answer questions, practical laboratory experiments, experiment construction and the students ability to evaluate experiment plans were compared. Having Swedish as mother tongue also was included as an explanatory variable since we suspected that some of the assessment methods in reality rather evaluates the linguistic skills in interpreting texts rather than evaluating the content knowledge of the subject. The results for each student when different methods were used were compared in order to evaluate if some of the methods for assessment gave similar results or if the methods induced differences in the results for the same student. We use ordination techniques to assess and visualize main trends in the data and linear models and classification trees to evaluate specific associations. There is correlation between results from several assessment methods, there are positive correlation between combinations of results from long answers, experiment and experiment construction, meaning students who showed good results with one method did so also with the others - but in some comparisons like long answer questions and multiple choice questions good results were independent of each other. There was a negative effect of having a non-Swedish mother tongue on the results in multiple choice questionnaires, but a positive effect of a non-Swedish mother tongue on the combined scores on experimental construction and experiment. Linear models show that good achievements in experimental construction are explained by high summed scores of Doll´s criteria, the four R’s richness, recursion, relations, and rigor.

Place, publisher, year, edition, pages
Libreria universitaria, 2015
National Category
Didactics
Identifiers
urn:nbn:se:hig:diva-23387 (URN)978-88-6292-600-3 (ISBN)
Conference
New perspectives in science education, 4th ed, Florence, March 20-21, 2015.
Available from: 2015-09-18 Created: 2017-01-27 Last updated: 2021-06-21Bibliographically approved
Projects
Environmental Risk Governance of the Baltic Sea (RISKGOV) [A032-2008_OSS]; Södertörn University
Organisations
Identifiers
ORCID iD: ORCID iD iconorcid.org/0000-0002-5013-6462

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