| 1. |
- Forsberg, Nils, 1981-, et al.
(författare)
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Population structure in landrace barley (Hordeum vulgare L.) during the late 19th century crop failures in Fennoscandia
- 2019
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Ingår i: Heredity. - : Springer Science and Business Media LLC. - 0018-067X .- 1365-2540. ; 123:6, s. 733-745
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Tidskriftsartikel (refereegranskat)abstract
- Agricultural disasters and the subsequent need for supply of relief seed can be expected to influence the genetic composition of crop plant populations. The consequences of disasters and seed relief have, however, rarely been studied since specimens sampled before the events are seldomly available. A series of crop failures struck northern Fennoscandia (Norway, Sweden and Finland) during the second half of the 19th century. In order to assess population genetic dynamics of landrace barley (Hordeum vulgare), and consequences of crop failure and possible seed relief during this time period, we genotyped seeds from 16 historical accessions originating from two time periods spanning the period of repeated crop failure. Reliable identification of genetic structuring is highly dependent on sampling regimes and detecting fine-scale geographic or temporal differentiation requires large sample sizes. The robustness of the results under different sampling regimes was evaluated by analyzing subsets of the data and an artificially pooled dataset. The results led to the conclusion that six individuals per accession were insufficient for reliable detection of the observed genetic structure. We found that population structure among the data was best explained by collection year of accessions, rather than geographic origin. The correlation with collection year indicated a change in genetic composition of landrace barley in the area after repeated crop failures, likely a consequence of introgression of relief seed in local populations. Identical genotypes were found to be shared among some accessions, suggesting founder effects and local seed exchange along known routes for trade and cultural exchange.
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| 2. |
- Hagenblad, Jenny, Associate Professor, 1974-, et al.
(författare)
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Population structure in landrace barley (Hordeum vulgare L.) during the late 19th century crop failures in Fennoscandia
- 2019
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Annan publikationabstract
- Agricultural disasters and the subsequent need for supply of relief seed can be expected to influence the genetic composition of crop plant populations. The consequences of disasters and seed relief have, however, rarely been studied since specimens sampled before the events are seldomly available. A series of crop failures struck northern Fennoscandia (Norway, Sweden and Finland) during the second half of the 19th century. In order to assess population genetic dynamics of landrace barley (Hordeum vulgare), and consequences of crop failure and possible seed relief during this time period, we genotyped seeds from 16 historical accessions originating from two time periods spanning the period of repeated crop failure. Reliable identification of genetic structuring is highly dependent on sampling regimes and detecting fine-scale geographic or temporal differentiation requires large sample sizes. The robustness of the results under different sampling regimes was evaluated by analyzing subsets of the data and an artificially pooled dataset. The results led to the conclusion that six individuals per accession were insufficient for reliable detection of the observed genetic structure. We found that population structure among the data was best explained by collection year of accessions, rather than geographic origin. The correlation with collection year indicated a change in genetic composition of landrace barley in the area after repeated crop failures, likely a consequence of introgression of relief seed in local populations. Identical genotypes were found to be shared among some accessions, suggesting founder effects and local seed exchange along known routes for trade and cultural exchange. MethodsIndividual 19th century seeds were genotyped using an Illumina Golden Gate assay for the C-384 barley SNP set detailed by Moragues et al. (2010). Quality control based on CG10 scores led to the exclusion of 26 low performance samples, including all nine negative controls. Samples with more than 25 % missing data (39 samples), markers with more than 20 % missing data (92 SNPs) and monomorphic SNPs (140 SNPs) were also excluded, in that order. Usage notesHeterozygous loci and missing values are given in the data set as -9. Genotypes in the dataset are homozygous genotypes.
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| 3. |
- Kirsten, Nils, 1981-
(författare)
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Kompetensutveckling som styrning : Om statliga insatser för lärares kompetensutveckling och hur de förhandlas i lärares lokala praktik
- 2020
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Doktorsavhandling (övrigt vetenskapligt/konstnärligt)abstract
- Teachers’ professional development (PD) is currently promoted as an important element of the pursuit of improved school results by researchers, politicians, and international organizations. Policy actors argue that the quality of teaching is the factor within school systems with the greatest significance for students’ learning outcomes, and that PD is an important instrument for enhancing such quality. Teachers’ PD has also become a higher priority among policy makers due to decentralization reforms that have deprived states of many of the policy measures previously available to them. However, teachers’ PD has rarely been investigated as a policy instrument. This is unfortunate for several reasons, including that surrounding governance structures are important for the effects of PD, and that most of the PD in which teachers partake is initiated by actors such as states, municipalities, or school leadership. Based on these arguments, the aim of this thesis is to develop knowledge about how teachers’ PD functions as an instrument for governing teachers’ work. The dissertation explores this issue through a comparative investigation of state initiatives for teachers’ PD in Sweden during the period 1991-2015. The dissertation devotes special attention to one intervention, the Literacy Boost (in Swedish Läslyftet), by also investigating its enactment at six schools during the 2015/16 academic year. The thesis shows that the Swedish state’s spending for teachers’ PD and school development increased significantly during the investigated period, especially after 2007, and, likewise, that teachers’ participation in PD increased. Moreover, article I shows that school agencies, since 1991, increased their engagement in teachers’ PD, that PD prescriptions became more detailed, and that evaluations of local enactment were used in more comprehensive ways. Based on the local enactment of the Literacy Boost, articles II and III illuminated the difficulty of translating external and cross-curricular messages to teachers’ local practice. While the PD model’s form of governance effectively induced teachers to discuss and enact instructions in the PD material, enactments took the form of additional activities rather than being made coherent with teachers’ present subject teaching. Thus, articles II and III indicated that, in order for PD messages to contribute to teaching, governance should be more specific to teachers’ present practice. Lastly, the dissertation illuminates a paradox regarding state-initiated PD in decentralized school systems. Although decentralization increases the state’s incentives to engage in teachers’ PD, the state’s ability to adapt PD initiatives to local needs is limited by the principles of decentralization.
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| 4. |
- Lundström, Maria, 1986-, et al.
(författare)
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Genetic analyses of Scandinavian desiccated, charred and waterlogged remains of barley (Hordeum vulgare L.)
- 2018
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Ingår i: Journal of Archaeological Science. - : Elsevier BV. - 2352-409X .- 2352-4103. ; 22, s. 11-20
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Tidskriftsartikel (refereegranskat)abstract
- Barley, Hordeum vulgare L., has been cultivated in Fennoscandia (Denmark, Norway, Sweden, Finland) since the start of the Neolithic around 4000 years BCE. Genetic studies of extant and 19th century barley landraces from the area have previously shown that distinct genetic groups exist with geographic structure according to latitude, suggesting strong local adaptation of cultivated crops. It is, however, not known what time depth these patterns reflect. Here we evaluate different archaeobotanical specimens of barley, extending several centuries in time, for their potential to answer this question by analysis of aDNA. Forty-six charred grains, nineteen waterlogged specimens and nine desiccated grains were evaluated by PCR and KASP genotyping. The charred samples did not contain any detectable endogenous DNA. Some waterlogged samples permitted amplification of endogenous DNA, however not sufficient for subsequent analysis. Desiccated plant materials provided the highest genotyping success rates of the materials analysed here in agreement with previous studies. Five desiccated grains from a grave from 1679 in southern Sweden were genotyped with 100 SNP markers and data compared to genotypes of 19th century landraces from Fennoscandia. The results showed that the genetic composition of barley grown in southern Sweden changed very little from late 17th to late 19th century and farmers stayed true to locally adapted crops in spite of societal and agricultural development.
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| 5. |
- Vavruch, Ludvig, et al.
(författare)
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Vertebral Axial Asymmetry in Adolescent Idiopathic Scoliosis.
- 2018
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Ingår i: Spine Deformity. - : Elsevier. - 2212-134X. ; 6:2, s. 112-120.e1
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Tidskriftsartikel (refereegranskat)abstract
- Study DesignRetrospective study.ObjectivesTo investigate parameters of axial vertebral deformation in patients with scoliosis compared to a control group, and to determine whether these parameters correlated with the severity of spine curvature, measured as the Cobb angle.Summary of Background DataAdolescent idiopathic scoliosis (AIS) is the most common type of spinal deformity. Many studies have investigated vertebral deformation, in terms of wedging and pedicle deformations, but few studies have investigated actual structural changes within vertebrae.MethodsThis study included 20 patients with AIS (Lenke 1–3, mean age: 15.6 years, range: 11–20). We compared preoperative low-dose computed tomography(CT) examinations of patients with AIS to those of a control group matched for age and sex. The control individuals had no spinal deformity, but they were admitted to the emergency department for trauma CTs. We measured the Cobb angles and the axial vertebral rotation (AVR), axial vertebral bodyasymmetry (AVBA), and frontal vertebral body rotation (FVBR) for the superior end, inferior end, and apical vertebrae, with in-house–developed software. Correlations between entities were investigated with the Pearson correlation test.ResultsThe average Cobb angles were 49.3° and 1.3° for the scoliotic and control groups, respectively. The patient and control groups showed significant differences in the AVRs of all three vertebra levels (p < .01), the AVBAs of the superior end and apical vertebrae (p < .008), and the FVBR of the apical vertebra (p = .011). Correlations were only found between the AVBA and FVBR in the superior end vertebra (r = 0.728, p < .001) and in the apical vertebra (r = 0.713, p < .001).ConclusionsCompared with controls, patients with scoliosis showed clear morphologic differences in the midaxial plane vertebrae. Differences in AVR, AVBA, and FVBR were most pronounced at the apical vertebra. The FVBR provided valuable additional information about the internal rotation and deformation of vertebrae.Level of EvidenceLevel III.
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