61 research outputs found
The future looks like the past: Introgression of domesticated Atlantic salmon escapees in a risk assessment framework
Escapes of domesticated fish from aquaculture, followed by interbreeding with wild conspecifics, represent a threat to the genetic integrity and evolutionary trajectory of natural populations. Approximately fifty years of Atlantic salmon production has left an unprecedented legacy of widespread introgression of domesticated escapees in wild Norwegian populations. A major question, however, is whether current aquaculture practice will lead to additional introgression in the near future. As part of the updated Norwegian risk assessment of fish farming, we conducted a risk assessment for further introgression of domesticated escapees in wild populations in Norway. Extensive data of reported numbers of escapees, observed proportions of escapees in rivers, removal of escapees pre‐spawning, and the resilience of wild populations through demographic and genetic status informed the risk assessment. The analysis revealed that rivers in 10 of the 13 aquaculture production zones covering Norway display a moderate or high risk of further introgression of domesticated escapees. This comes in addition to widespread introgression that is already documented. We therefore conclude that so long as aquaculture production continues at its present level and form, there is a moderate‐to‐high risk of further introgression of domesticated salmon in many native populations throughout much of Norway.publishedVersio
Perinatal exposure to potential endocrine disrupting chemicals and autism spectrum disorder: From Norwegian birth cohort to zebrafish studies
publishedVersionpublishedVersio
Comparison of Mitochondrial Respiration in M. triceps brachii and M. vastus lateralis Between Elite Cross-Country Skiers and Physically Active Controls
RationaleThe main purposes of this study were to compare mitochondrial respiration in M. triceps brachii and M. vastus lateralis between elite cross-country (XC) skiers and physically active controls (CON), and to explore the associations between mitochondrial respiration in these muscles and peak oxygen uptake (V˙O2peak) in arm- and leg-dominant exercise modes.MethodsThirteen male elite XC skiers (age: 25 ± 4; peak oxygen uptake (V˙O2peak): 75.5 ± 4.2 mL⋅kg-1⋅min-1) and twelve CON (age: 26 ± 3; V˙O2peak: 57.2 ± 6.4 mL⋅kg-1⋅min-1) had microbiopsies taken from M. vastus lateralis and M. triceps brachii, which were analyzed for various measures of mitochondrial respiration using high-resolution respirometry. Thereafter, all participants tested V˙O2peak in both running (RUN) and upper body poling (UBP).ResultsXC skiers had generally higher mitochondrial respiration in M. triceps brachii compared to CON (P < 0.001), whereas no significant group-differences in mitochondrial respiration in M. vastus lateralis were revealed. XC skiers had higher mitochondrial respiration in M. triceps brachii compared to M. vastus lateralis (P = 0.005–0.058), whereas in CON, most mitochondrial respiration measures were higher in M. vastus lateralis than in M. triceps brachii (P < 0.01). When all athletes were pooled, there was a strong positive correlation between V˙O2peak in UBP and mitochondrial respiration in M. triceps brachii on several measures (P < 0.01), whereas no correlation was found for RUN.ConclusionThe higher mitochondrial respiration found in M. triceps brachii compared to M. vastus lateralis among our elite XC skiers demonstrates the potential for the arm muscles to adapt to aerobic endurance training. The opposite pattern found in CON, clearly showed lower mitochondrial respiration in M. triceps brachii compared to XC skiers, whereas respiration in M. vastus lateralis did not differ between groups. The strong positive correlation between mitochondrial respiration in M. triceps brachii and V˙O2peak in UBP indicate that arm muscles’ respiratory function may be a limiting factor for V˙O2peak in arm-dominant exercise modes
Forskningsetiske retningslinjer for samfunnsvitenskap og humaniora
Den nasjonale forskningsetiske komité for samfunnsvitenskap og humaniora (NESH) er et uavhengig og rådgivende organ, som har ansvar for å utarbeide nasjonale forskningsetiske retningslinjer. Den første utgaven av NESHs retningslinjer ble utgitt i 1993, og de har kommet i reviderte utgaver i 1999, 2006 og 2016. For mer om NESH og retningslinjene, se vedlegg.
I denne utgaven har NESH valgt å fremheve og tydeliggjøre de grunnleggende forskningsetiske normene. Formålet er å fremheve NESHs retningslinjer som en selvstendig kilde til forskningsetisk refleksjon og kontinuering diskusjon i forskerfellesskapet. NESH har også presisert hvordan forskning i økende grad er under press, og hvordan ulike aktører som oppdragsgivere, finansiører og samarbeidspartnere har medansvar for å ivareta forskningsetikken. Videre er skillet mellom etikk og juss presisert for å tydeliggjøre grenseflatene mot henholdsvis gransking av vitenskapelig uredelighet og krav om rettsgrunnlag ved behandling av personopplysninger.
Høsten 2020 ble det reviderte utkastet til nasjonale retningslinjer sendt på høring. NESH mottok over 60 innspill fra forskere, forskningsinstitusjoner og andre forskningsaktører. En arbeidsgruppe bestående av Elisabeth Staksrud (leder), Ivar Kolstad (nestleder) og Vidar Enebakk (sekretariatsleder) har gått gjennom alle innspill og utarbeidet forslag, som er grundig drøftet og vedtatt av alle medlemmene i komiteen.publishedVersio
The genetic architecture of the human cerebral cortex
The cerebral cortex underlies our complex cognitive capabilities, yet little is known about the specific genetic loci that influence human cortical structure. To identify genetic variants that affect cortical structure, we conducted a genome-wide association meta-analysis of brain magnetic resonance imaging data from 51,665 individuals. We analyzed the surface area and average thickness of the whole cortex and 34 regions with known functional specializations. We identified 199 significant loci and found significant enrichment for loci influencing total surface area within regulatory elements that are active during prenatal cortical development, supporting the radial unit hypothesis. Loci that affect regional surface area cluster near genes in Wnt signaling pathways, which influence progenitor expansion and areal identity. Variation in cortical structure is genetically correlated with cognitive function, Parkinson's disease, insomnia, depression, neuroticism, and attention deficit hyperactivity disorder
Texture-based probability mapping for automatic scar assessment in late gadolinium-enhanced cardiovascular magnetic resonance images
Purpose
To evaluate a novel texture-based probability mapping (TPM) method for scar size estimation in LGE-CMRI.
Methods
This retrospective proof-of-concept study included chronic myocardial scars from 52 patients. The TPM was compared with three signal intensity-based methods: manual segmentation, full-width-half-maximum (FWHM), and 5-standard deviation (5-SD). TPM is generated using machine learning techniques, expressing the probability of scarring in pixels. The probability is derived by comparing the texture of the 3 × 3 pixel matrix surrounding each pixel with reference dictionaries from patients with established myocardial scars. The Sørensen-Dice coefficient was used to find the optimal TPM range. A non-parametric test was used to test the correlation between infarct size and remodeling parameters. Bland-Altman plots were performed to assess agreement among the methods.
Results
The study included 52 patients (76.9% male; median age 64.5 years (54, 72.5)). A TPM range of 0.328–1.0 was found to be the optimal probability interval to predict scar size compared to manual segmentation, median dice (25th and 75th percentiles)): 0.69(0.42–0.81). There was no significant difference in the scar size between TPM and 5-SD. However, both 5-SD and TPM yielded larger scar sizes compared with FWHM (p < 0.001 and p = 0.002). There were strong correlations between scar size measured by TPM, and left ventricular ejection fraction (LVEF, r = −0.76, p < 0.001), left ventricular end-diastolic volume index (r = 0.73, p < 0.001), and left ventricular end-systolic volume index (r = 0.75, p < 0.001).
Conclusion
The TPM method is comparable with current SI-based methods, both for the scar size assessment and the relationship with left ventricular remodeling when applied on LGE-CMRI.publishedVersio
Calcium signaling as a possible mechanism behind increased locomotor response in zebrafish larvae exposed to a human relevant persistent organic pollutant mixture or PFOS
Persistent organic pollutants (POPs) are widespread in the environment and their bioaccumulation can lead to adverse health effects in many organisms. Previously, using zebrafish as a model vertebrate, we found larvae exposed to a mixture of 29 POPs based on average blood levels from the Scandinavian population showed hyperactivity, and identified perfluorooctanesulfonic acid (PFOS) as the driving agent for the behavioral changes. In order to identify possible mechanisms, we exposed zebrafish larvae from 6 to 96 h post fertilization to the same mixture of POPs in two concentrations or a single PFOS exposure (0.55 and 3.83 μM) and performed behavioral tests and transcriptomics analysis. Behavioral alterations of exposed zebrafish larvae included hyperactivity and confirmed previously reported results. Transcriptomics analysis showed upregulation of transcripts related to muscle contraction that is highly regulated by the availability of calcium in the sarcoplasmic reticulum. Ingenuity pathway analysis showed that one of the affected pathways in larvae exposed to the POP mixture and PFOS was calcium signaling via the activation of the ryanodine receptors (RyR). Functional analyses with RyR inhibitors and behavioral outcomes substantiate these findings. Additional pathways affected were related to lipid metabolism in larvae exposed to the lower concentration of PFOS. By using omics technology, we observed that the altered behavioral pattern in exposed zebrafish larvae may be controlled directly by mechanisms affecting muscle function rather than via mechanisms connected to neurotoxicity.publishedVersio
Die Rolle von Abstraktheit und Wortbedeutungen bei der Unterscheidung von wörtlichen und nicht-wörtlichen Bedeutungen von deutschen Partikelverben
Ziel dieser Arbeit ist es, die wörtliche bzw. metaphorische Verwendung von deutschen Partikelverben richtig identifizieren zu können. Als erster Schritt werden hier der von Köper und Schulte im Walde (2016) vorgeschlagene Klassifizierer in Python reimplementiert und die Menge der verwendeten Daten erweitert. Als zweiten zentralen Schritt dieser Arbeit variieren wir die verwendeten Abstraktheitsfeatures und experimentieren mit eigens erzeugten Werten. Als letztes Feature werfen wir einen Blick auf die Verwendung der Wortbedeutungen in Form der im Duden definierten Senses, welche wir mithilfe des Lesk-Algorithmus (Lesk, 1986) sowie Wortvektoren bestimmen
Comparison of Physiological and Perceptual Responses to Upper-, Lower-, and Whole-Body Exercise in Elite Cross-Country Skiers
Undebakke, V, Berg, J, Tjønna, AE, and Sandbakk, Ø. Comparison of physiological and perceptual responses to upper-, lower-, and whole-body exercise in elite cross-country skiers. J Strength Cond Res 33(4): 1086–1094, 2019—The primary purpose of the present study was to compare physiological and perceptual responses to maximal and submaximal exercise between upper-, lower-, and whole-body exercise modes in elite cross-country (XC) skiers. Twelve elite XC skiers performed 5–7 submaximal 5-minute stages and an incremental test to exhaustion using upper-body poling (UP), running (RUN), and diagonal skiing (DIA), randomized on 3 separate days. Here, power output, cardiorespiratory variables, heart rate (HR), blood lactate concentration (BLa), and rating of perceived exertion (RPE) were determined. Peak power output increased gradually from UP to RUN and DIA, whereas peak oxygen uptake (V[Combining Dot Above]O2peak), peak HR, O2pulse, and total RPE were clearly lower in UP than RUN and DIA (p < 0.05). At submaximal workloads matched for either RPE, %HR, or BLa, the main pattern was that BLa was higher and V[Combining Dot Above]O2 and HR lower in UP compared with RUN and DIA (p < 0.05). DIA showed ∼10 and 35% higher V[Combining Dot Above]O2 than RUN and UP at RPE 10–13 and had lower muscular RPE values than UP and RUN at a given % of peak HR (p < 0.05). Most of the differences in cardiorespiratory variables between modes were eliminated when they were normalized to V[Combining Dot Above]O2peak or peak HR in the respective mode. Because of the low power production in UP, endurance training in this mode exhibits too low values of V[Combining Dot Above]O2 to tax the cardiovascular system sufficiently. In RUN and DIA, the similar V[Combining Dot Above]O2peak values indicate that both modes can be effectively used during high-intensity training and to determine V[Combining Dot Above]O2max in elite XC skiers. However, the relatively high V[Combining Dot Above]O2 values at low perceptual stress with submaximal DIA indicate that the large amount of power produced when combining upper- and lower-body work exhibits high oxidative flux even during low-intensity training. Overall, these findings should be taken into account when athletes and coaches are monitoring and prescribing training in future approaches, in particular in sports where athletes vary between training with upper-, lower-, and whole-body exercise modes
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