The Effects of Alcohol Intoxication on Neuronal Activation at Different Levels of Cognitive Load

The aim of this study was to investigate how alcohol intoxication at two blood alcohol concentrations (BAC) affected neuronal activation during increasing levels of cognitive load. For this purpose we used functional magnetic resonance imaging (fMRI) together with a working memory n-back paradigm with three levels of difficulty. Twenty-five healthy male participants were scanned twice on two separate days. Participants in the control group (N=13) were scanned after drinking a soft-drink at both scanning sessions, while participants in the alcohol group (N=12) were scanned once after drinking an alcoholic beverage resulting in a BAC of 0.02%, and once after drinking an alcoholic beverage resulting in a BAC of 0.08%. A decrease in neuronal activation was seen in the dorsal anterior cingulate cortex (dACC) and in the cerebellum in the alcohol group at the BAC of 0.08% when the participants performed the most demanding task. The dACC is important in cognitive control, working memory, response inhibition, decision making and in error monitoring. The results have revealed that the effect of alcohol intoxication on brain activity is dependent on BAC and of cognitive load

Relative Age Effect Among the Best Norwegian Track and Field Athletes of All Time: Comparisons of Explosive and Endurance Events

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Comparison of Short-Sprint and Heavy Strength Training on Cycling Performance

Copyright © 2019 Kristoffersen, Sandbakk, Rønnestad and Gundersen. This is an open-access article distributed under the terms of the Creative Commons Attribution License (CC BY). The use, distribution or reproduction in other forums is permitted, provided the original author(s) and the copyright owner(s) are credited and that the original publication in this journal is cited, in accordance with accepted academic practice. No use, distribution or reproduction is permitted which does not comply with these terms.Purpose: To compare the effects of short-sprint training (SST) and heavy-strength training (HST) following a 4-week strength-training period on sprint and endurance capacities in well-trained cyclists. Methods: Twenty-eight competitive cyclists (age 29 ± 6 years) with maximal oxygen uptake (VO˙ 2max) of 61.1 ± 5.9 mL·min−1 ·kg−1 participated. After a 4-weeks preparation strength-training period, the participants were randomized to add either HST or SST to their usual endurance training for the subsequent 6 weeks. Body composition, VO˙ 2max and power output at blood lactate concentration ([La−]) of 4 mmol·L −1 , as well as a 100 min cycling test including 6 and 30-s sprints, 60 min cycling at [La−] of 2 mmol·L −1 and 5-min all-out cycling were performed before the 4-week preparation strengthtraining period, and before and after the 6-week intervention period. In addition, 1 repetition maximum (RM) in half-squat and 55-m maximal sprints on the cyclists’ own bikes were measured before and after the 6-week intervention. Results: SST was superior to HST in 6-s sprint performance, both in a fresh state (4.7 ± 2.6% vs. 1.1 ± 3.5%) and after prolong cycling (6.1 ± 1.8% vs. 1.8 ± 4.2%), in 30-s sprint (3.7 ± 2.8% vs. 1.3 ± 2.5%) and in 55-m seated sprint on own bike (4.3 ± 2.1% vs. 0.2 ± 1.8%) (all p < 0.002). HST induced a larger 1RM improvement in the half-squat test than SST (9.3 ± 3.6% vs. −3.9 ± 3.8%; p < 0.001). No group differences were revealed in the 5-min all-out test, VO˙ 2max, power output at 4 mmol·L −1 [La−], or in gross efficiency. Conclusion: SST led to a greater increase in average and peak power output on all sprint tests compared to HST, whereas HST led to a greater increase in maximal strength. No group differences were found in relative changes in endurance capacities. Altogether, our results show a high degree of specificity in the adaptations of both SST and HST.publishedVersio

The Price Responsiveness of Shale Producers: Evidence From Micro Data

Shale oil producers respond positively and significantly to favourable oil price signals. This finding is established using a novel proprietary data set consisting of more than 200,000 shale wells across ten U.S. states spanning almost two decades. We document large heterogeneity in the estimated responses across the various shale wells, suggesting that aggregation bias is an important issue for this kind of analysis. We find responses to be stronger for the largest oil producing firms, among wells that are spaced further apart and in regions where the density of shale wells is higher. The response also depend on the level of production. Our empirical results calls for new models that can account for a growing share of shale oil in the U.S., the inherent flexibility of shale extraction technology in production and the role of shale oil in transmitting oil price shocks to the U.S. economy

The Price Responsiveness of Shale Producers: Evidence from Micro Data

We show that shale oil producers respond positively to favourable oil price signals, and that this response is mainly associated with the timing of production decisions through well completion and refracturing, consistent with the Hotelling theory of optimal extraction. This finding is established using a novel proprietary data set consisting of more than 200,000 shale wells across ten U.S. states spanning almost two decades. We document large heterogeneity in the estimated responses across the various shale wells, suggesting that aggregation bias is an important issue for this kind of analysis. Our empirical results call for new models that can account for a growing share of shale oil in the U.S., the inherent flexibility of shale extraction technology in production and the role of shale oil in transmitting oil price shocks to the global economy.publishedVersio

Low cadence interval training at moderate intensity does not improve cycling performance in highly trained veteran cyclists

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Vurdering av kraftproduksjon fra strømning langs ferjefri E39

Rapporten ser på potensialet for kraftproduksjon i forbindelse med mulige brukryssinger langs en fergefri E39. Da tidevannsstrømmen er den mest stabile strømmen har vi konsentrert oss om denne. Energien i strømmen er anslått på grunnlag av etablerte formler for energitetthet og energifluks. Andre former for energiuttak er også kort omtalt. Både strømobservasjoner og estimater av strømstyrke basert på tidevannsforskjeller og fjordarealer er brukt i estimatene. Generelt viser våre beregninger at potensialet for energiuttak fra tidevannsstrøm er begrenset. Dette skyldes at de planlagte bruene vil gå over relativt breie og dype fjorder hvor en må regne med små strømhastigheter. Det finnes flere kjente sterke tidevannsstrømmer nær den aktuelle veitraseen der det bør være mulig å produsere energi fra tidevannsstrøm ved hjelp av turbiner. Noen av disse er omtalt.Statens vegvesen Vegdirektorate

Organisering av svømmeopplæring, selvberging og livredning i grunnskolen: Bruk av eksterne aktører og egne ansatte

Skriftserien ved HVL, RapportSiden 2015/2016 har regjeringens nasjonale satsing på svømmeopplæring bidratt til økt samarbeid mellom skoler og eksterne aktører som frivillige organisasjoner og svømmeklubber. Dette samarbeidet har vært tema for diskusjon, særlig med tanke på balansen mellom skolens ansvar og bruken av ekstern kompetanse. Omtrent halvparten av skolene gjennomfører opplæringen med egne ansatte, mens den andre halvparten samarbeider med eksterne aktører. Slike samarbeid er mest utbredt i større kommuner og skoler, spesielt innen svømming og selvberging, mens mindre skoler i større grad bruker egne ansatte. Når det gjelder opplæring i livredning, rapporterer litt under halvparten av skolene om samarbeid med eksterne aktører, uavhengig av kommune- eller skolestørrelse. Vanlige årsaker til samarbeid med eksterne aktører inkluderer kommunale beslutninger, kvalitetshensyn, og manglende kompetanse blant skolens ansatte. Frivillige organisasjoner og svømmeinstruktører/-klubber er ofte involvert, og skolene bidrar hovedsakelig med assistanse og logistikk. På den andre siden oppgir skolene som benytter egne ansatte at det er enklere, gir bedre helhet i opplæringen, og bygger på elevenes kjennskap til lærerne. Kroppsøvingslærere med relevant utdanning eller kurs er vanligst ansvarlige. Samarbeid med eksterne aktører har tydeliggjort skolens behov for kompetanse, men også utfordringer knyttet til organisering og ansvarsfordeling. For å sikre en helhetlig opplæring og progresjon, er det viktig at skolene og kommunene evaluerer hvordan opplæringen best kan organiseres med eller uten eksterne aktører, samtidig som skolens ansvar ivareta

Soft bottom benthos and responses to climate variation and eutrophication in Skagerrak

Skagerrak has been subject to several anthropogenic influences over the past decades, with climate change and eutrophication being considered as the most serious and large-scale disturbance factors. The present study reports monitoring data from six soft bottom stations in 50–380 m depth at the Norwegian Skagerrak coast aimed at investigating to which degree changes in environmental conditions have affected species communities and diversity. Sampling was carried out yearly in the period 1990–2010. Links between benthic community patterns and climate factors and physicochemical variables from the water mases were examined using uni- and multivariate statistical methods. Throughout the period species richness gradually increased. Although all stations showed distinct species assemblages, the community composition gradually changed towards increased importance of sensitive small molluscs and tube-building annelids concurrent with a general temperature increase and reduction of nutrients in the water masses. The trend was largely similar over the stations, indicating that large-scale changes in the Skagerrak water masses were driving factors compared to possible influences from local sources. The faunal changes during the study period thus indicate an improved status of the soft bottom benthos, which possibly could be related to a reduction in the eutrophication. On a shorter scale, species richness was found to vary in relation to North Atlantic Oscillation (NAO) Index in the previous year (decline), nutrient concentrations in spring (decline), and winter water temperature (incline).acceptedVersio