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Abstract Background Insertion of an external ventricular drain (EVD) is a first-line treatment of acute hydrocephalus caused by aneurysmal subarachnoid haemorrhage (aSAH). Once the patient is clinically stable, the EVD is either removed or replaced by a permanent internal shunt. The optimal strategy for cessation of the EVD is unknown. Prompt closure carries a risk of acute hydrocephalus or redundant shunt implantations, whereas gradual weaning may increase the risk of EVD-related infections. Methods DRAIN (Danish RAndomised Trial of External Ventricular Drainage Cessation IN Aneurysmal Subarachnoid Haemorrhage) is an international multicentre randomised clinical trial comparing prompt closure versus gradual weaning of the EVD after aSAH. The primary outcome is a composite of VP-shunt implantation, all-cause mortality, or EVD-related infection. Secondary outcomes are serious adverse events excluding mortality and health-related quality of life (EQ-5D-5L). Exploratory outcomes are modified Rankin Scale, Fatigue Severity Scale, Glasgow Outcome Scale Extended, and length of stay in the neurointensive care unit and hospital. Outcome assessment will be performed 6 months after ictus. Based on the sample size calculation (event proportion 80% in the gradual weaning group, relative risk reduction 20%, alpha 5%, power 80%), 122 participants are required in each intervention group. Outcome assessment for the primary outcome, statistical analyses, and conclusion drawing will be blinded. Two independent statistical analyses and reports will be tracked using a version control system, and both will be published. Based on the final statistical report, the blinded steering group will formulate two abstracts. Conclusion We present a pre-defined statistical analysis plan for the randomised DRAIN trial, which limits bias, p-hacking, and data-driven interpretations. This statistical analysis plan is accompanied by tables with simulated data, which increases transparency and reproducibility. Trial registration ClinicalTrials.gov identifier: NCT03948256. Registered on May 13, 2019.

Extreme winds are by far the largest contributor to Norway’s insurance claims related to natural hazards. The predictive skills of four different damage functions are assessed for Norway at the municipality and national levels on daily and annual temporal scales using municipality-level insurance data and the high-resolution Norwegian hindcast (NORA3) wind speed data for the period 1985–2020. Special attention is given to extreme damaging events and occurrence probabilities of wind-speed-induced damage. Because of the complex topography of Norway and the resulting high heterogeneity of the population density, the wind speed is weighted with the population. The largest per capita losses and severe damage occur most frequently in the western municipalities of Norway, which are more exposed to incoming storms from the North Atlantic, whilst there are seldom any large losses further inland. There is no single damage function that outperforms others. However, a good agreement between the observed and estimated losses at municipality and national levels for a combination of damage functions suggests their usability in estimating severe damage associated with windstorms. Furthermore, the damage functions are able to successfully reconstruct the geographical pattern of losses caused by extreme windstorms with a high degree of correlation. From event occurrence probabilities, the present study devises a damage classifier that exhibits some skill at distinguishing between daily damaging and non-damaging events at the municipality level. While large-loss events are well captured, the skewness and zero inflation of the loss data greatly reduce the quality of both the damage functions and the classifier for moderate- and weak-loss events.

Abstract The Norwegian government recently agreed on the goal 30by40, which involves opening Norwegian offshore areas to host 30 GW of installed wind power by 2040. We address this goal by presenting a first mapping of wind power suitability scores (WPSS) for the entire Norwegian economic zone (NEZ) using a multi‐criteria decision analysis framework (MCDA), namely, the analytical hierarchical process (AHP) approach. We obtain WPSS considering relevant criteria like wind resources, techno‐economic aspects, social acceptance, environmental considerations, and met‐ocean constraints such as wind and wave conditions. The results starts with a baseline scenario, where the criterion importance is pairwise compared in the context of balancing economic incentives and conflicting interests. Additionally, to reveal regions that are robust to changes in criterion importance, we carry out a sensitivity analysis by introducing three additional scenarios. These scenarios represent stereotypical actors with distinct preferences for siting of wind farms: the investor, the environmentalist, and the fisherman. The results show that the southern part of the NEZ is the most suitable and robust region for offshore wind power deployment. This region receives the highest suitability category (“very high” suitability for wind power application) throughout all the scenarios. Areas in the Norwegian part of the Barents Sea and the near‐coastal areas outside mid‐Norway are also well suited regions, but these are more sensitive to the choice of criterion importance. The use of AHP within the framework of MCDA is shown to be a promising tool for pinpointing the best Norwegian offshore areas for wind power application.

Abstract Resistance breathing may restore cardiac output (CO) and cerebral blood flow (CBF) during hypovolemia. We assessed CBF and cerebral autoregulation (CA) during tilt, resistance breathing, and paced breathing in 10 healthy subjects. Blood velocities in the internal carotid artery (ICA), middle cerebral arteries (MCA, four subjects), and aorta were measured by Doppler ultrasound in 30° and 60° semi‐recumbent positions. ICA blood flow and CO were calculated. Arterial blood pressure (ABP, Finometer), and end‐tidal CO2 (ETCO2) were recorded. ICA blood flow response was assessed by mixed‐models regression analysis. The synchronization index (SI) for the variable pairs ABP–ICA blood velocity, ABP–MCA velocities in 0.005–0.08 Hz frequency interval was calculated as a measure of CA. Passive tilting from 30° to 60° resulted in 12% decrease in CO (p = 0.001); ICA blood flow tended to fall (p = 0.04); Resistance breathing restored CO and ICA blood flow despite a 10% ETCO2 drop. ETCO2 and CO contributed to ICA blood flow variance (adjusted R2: 0.9, p

IntroductionSurvivors of aneurysmal subarachnoid hemorrhage (aSAH) often recover without severe physical or cognitive deficits. However, strikingly low levels of engagement in productive employment have also been reported in aSAH patients with good or excellent outcomes. Knowledge about return to work (RTW) after aSAH and predictors of no RTW remain limited and controversial. The study aimed to delineate the return to maximum work capacity up to 5 years after the ictus in a larger number of consecutive aSAH patients from the entire aSAH severity spectrum and to identify demographic and medical predictors of no RTW.MethodsData were acquired from a prospective institutional database. We included all 500 aSAH survivors aged > 18 years who were treated between January 2012 and March 2018. In addition to gathering data on work status and the type of work at ictus, we retrieved demographical data and assessed aSAH severity based on the quantification of subarachnoid, intraventricular, and intraparenchymal blood (ICH), as well as the World Federation of Neurological Societies (WFNS) grade. We registered the mode of aneurysm repair (endovascular or surgical) and recorded complications such as vasospasm, newly acquired cerebral infarctions, and chronic hydrocephalus.ResultsFurthermore, work status and the grade of fatigue at follow-up were registered. RTW was assessed among 299 patients who were employed at ictus. Among them, 63.2% were women, and their age was 51.3 ± 9.4 (20–71) years. Return to gainful employment was 51.2%, with complete RTW accounting for 32.4%. The independent predictors of no RTW at ictus were age, the WFNS grade 3, and active smoking. The strongest independent predictor was the presence of clinically significant fatigue, which increased the risk of not returning to work by 5-fold. The chance to return to gainful employment significantly increased with the individual's years of education prior to their hemorrhage. The mode of aneurysm repair was not relevant with regard to RTW. Patients in the WFNS grades 1–2 more often returned to work than those in the WFNS grades 3–5, but our results indicate that neurological motor deficits are linked closer to no RTW than aSAH severity per se.ConclusionFatigue needs to be addressed as an important element on the path to return to work integration.

Windstorms cause severe damages and are the dominant natural hazard responsible for insurance payouts in Norway. Using future wind speeds from twenty bias corrected regional climate model simulations from EURO-CORDEX and four damage functions, fitted on municipality level to observed insurance losses, we estimate storm related losses to increase in all Norwegian counties due to climate change. At national level, there is an increase in storm losses in the far future, but some counties and municipalities can still exhibit a decrease in losses. Under a changing climate, despite a decrease in the 98th percentile of the wind speed, the most extreme winds increase, and this drives an increase in the windstorm damages. We also show that the wind load design values may need to be re-evaluated to take into account the changing wind speeds. In addition to climate change, the impact of future exposure changes in the form of population changes using municipality-level population projections is shown to be important for determining the level of future windstorm damage risk. Overall, the loss projections show a large spread, highlighting their sensitivity to the choice of the storm-damage function and to the choice of the simulation.

Measurement(s) atmospheric wind speed and wind power Technology Type(s) Computational technology

We validate a new high-resolution (3 km) numerical mesoscale weather simulation for offshore wind power purposes for the time period 2004–2016 for the North Sea and the Norwegian Sea. The 3 km Norwegian reanalysis (NORA3) is a dynamically downscaled data set, forced with state-of-the-art atmospheric reanalysis as boundary conditions. We conduct an in-depth validation of the simulated wind climatology towards the observed wind climatology to determine whether NORA3 can serve as a wind resource data set in the planning phase of future offshore wind power installations. We place special emphasis on evaluating offshore wind-power-related metrics and the impact of simulated wind speed deviations on the estimated wind power and the related variability. We conclude that the NORA3 data are well suited for wind power estimates but give slightly conservative estimates of the offshore wind metrics. In other words, wind speeds in NORA3 are typically 5 % (0.5 m s−1) lower than observed wind speeds, giving an underestimation of offshore wind power of 10 %–20 % (equivalent to an underestimation of 3 percentage points in the capacity factor) for a selected turbine type and hub height. The model is biased towards lower wind power estimates due to overestimation of the wind speed events below typical wind speed limits of rated wind power (u–13 m s−1) and underestimation of high-wind-speed events (u>11–13 m s−1). The hourly wind speed and wind power variability are slightly underestimated in NORA3. However, the number of hours with zero power production caused by the wind conditions (around 12 % of the time) is well captured, while the duration of each of these events is slightly overestimated, leading to 25-year return values for zero-power duration being too high for the majority of the sites. The model performs well in capturing spatial co-variability in hourly wind power production, with only small deviations in the spatial correlation coefficients among the sites. We estimate the observation-based decorrelation length to be 425.3 km, whereas the model-based length is 19 % longer.

Platinum-based chemotherapies such as cisplatin are used as first-line treatment for the paediatric tumour neuroblastoma. Although the majority of neuroblastoma tumours respond to therapy, there is a high fraction of high-risk neuroblastoma patients that eventually relapse with increased resistance. Here, we show that one key determinant of cisplatin sensitivity is phosphorylation of the cyclin-dependent kinase inhibitor p21Cip1/Waf1. A panel of eight neuroblastoma cell lines and a TH-MYCN mouse model were investigated for the expression of p21Cip1/Waf1 using RT-qPCR, Western blot, and immunofluorescence. This was followed by investigation of sensitivity towards cisplatin and the p21Cip1/Waf1 inhibitor UC2288. Whereas the cell lines and the mouse model showed low levels of un-phosphorylated p21Cip1/Waf1, the phosphorylated p21Cip1/Waf1 (Thr145) was highly expressed, which in the cell lines correlated to cisplatin resistance. Furthermore, the neuroblastoma cell lines showed high sensitivity to UC2288, and combination treatment with cisplatin resulted in considerably decreased cell viability and delay in regrowth in the two most resistant cell lines, SK-N-DZ and BE(2)-C. Thus, targeting p21Cip1/Waf1 can offer new treatment strategies and subsequently lead to the design of more efficient combination treatments for high-risk neuroblastoma.

Pore pressure is crucial in triggering debris slides and flows. Here we present measurements of groundwater pore pressure and temperature recorded by a piezometer 1.6 m below the surface on a slope susceptible to debris flows in western Norway. One of the largest oscillations in data collected over 4 years coincided with a debris flow event on the slope that occurred during storm Hilde on 15–16 November 2013. More than 100 landslides were registered during the storm. Precipitation totaled about 80–100 mm in 24 h, locally up to 129 mm, and an additional trigger factor for the landslides was a rapid rise in air temperature that caused snowmelt. In the studied slope a fraction of the precipitation first fell as snow. On 15 November, the groundwater level in the hillslope rose by 10 cm/h and reached 44 cm below the surface. At the same time, air temperature rose from 0 ∘C to over 8 ∘C, and the groundwater temperature dropped by 1.5 ∘C. The debris flow probably occurred late in the evening of 15 November, when the groundwater level reached its peak. Measurements of the groundwater in the hillslope in the period 2010–2013 show that the event in 2013 was not exceptional. Storm Dagmar on 25–26 December 2011 caused a similar rise in groundwater level but did not trigger any failures. The data suggest that during heavy rainstorms the slope is in a critical state for a landslide to be triggered for a short time – about 4–5 h.

Weather features, such as extratropical cyclones, atmospheric rivers (ARs), and fronts, contribute to substantial amounts of precipitation globally and are associated with different precipitation characteristics. However, future changes in these characteristics, as well as their representation in climate models, remain uncertain. We attribute 6‐hourly accumulated precipitation to cyclones, moisture transport axes (AR‐like features), fronts, and cold air outbreaks, and the combinations thereof in 10 ensemble members of the CESM2‐LE between 1960 and 2100 under the SSP3‐7.0 scenario. We find that, despite some biases in both precipitation and weather features, CESM2‐LE adeptly represents the precipitation characteristics associated with the different combinations of weather features. The combinations of weather features that contribute most to precipitation in the present climate also contribute the most to future changes, both due to changes in intensity as well as frequency. While the increase in precipitation intensity dominates the overall response for total precipitation in the storm track regions, the precipitation intensity for the individual weather features does not necessarily change significantly. Instead, approximately half of the increase in precipitation intensity in the storm track regions can be attributed to a higher occurrence of the more intensely precipitating combinations of weather features, such as the co‐occurrence of extratropical cyclones, fronts, and moisture transport axes. Plain Language Summary: Most precipitation is associated with weather features such as storms, atmospheric rivers, and fronts. Different combinations of these weather features are associated with different precipitation characteristics, but how these characteristics are represented in climate models as well as their possible future changes is not known. We attribute 6‐hourly accumulated precipitation to weather features, such as storms, fronts, and atmospheric rivers, from 1960 to 2100 under a high greenhouse emission scenario in a climate model. Despite some biases, the climate model represents the precipitation characteristics associated with these weather features well. We find that the weather features with the largest contribution to precipitation in the current climate also contribute the most to future changes in precipitation. The changes are caused by changes in both frequency of occurrence and precipitation intensity. Key Points: We attribute precipitation to cyclones, fronts, moisture transport axes, and cold air outbreaks in 10 ensemble members CESM2‐LE in 1960–2100CESM2‐LE adeptly represents the precipitation characteristics associated with the different weather features and their combinationsCo‐occurring weather features, associated with intense precipitation, contribute to a larger fraction of the precipitation in the future [ABSTRACT FROM AUTHOR]

This study uses a unique set of hourly wind speed data observed over a period of 16 years to quantify the potential of collective offshore wind power production. We address the well-known intermittency problem of wind power for five locations along the Norwegian continental shelf. Mitigation of wind power intermittency is investigated using a hypothetical electricity grid. The degree of mitigation is examined by connecting different configurations of the sites. Along with the wind power smoothing effect, we explore the risk probability of the occurrence and duration of wind power shutdown due to too low or high winds. Typical large-scale atmospheric situations resulting in long term shutdown periods are identified. We find that both the wind power variability and the risk of not producing any wind power decrease significantly with an increasing array of connected sites. The risk of no wind power production for a given hour is reduced from the interval 8.0 %–11.2 % for a single site to under 4 % for two sites. Increasing the array size further reduces the risk, but to a lesser extent. The average atmospheric weather pattern resulting in wind speed that is too low (too high) to produce wind power is associated with a high-pressure (low-pressure) system near the production sites.

Fatigue after aneurysmal subarachnoid hemorrhage (post-aSAH fatigue) is a frequent, often long-lasting, but still poorly studied sequel. The aim of the present study was to characterize the nature of post-aSAH fatigue with an itemized analysis of the Fatigue Severity Scale (FSS) and Mental Fatigue Scale (MFS). We further wanted to assess the association of fatigue with other commonly observed problems after aSAH: mood disorders, cognitive problems, health-related quality of life (HRQoL), weight gain, and return to work (RTW). Ninety-six good outcome aSAH patients with fatigue completed questionnaires measuring fatigue, depression, anxiety, and HRQoL. All patients underwent a physical and neurological examination. Cognitive functioning was assessed with a neuropsychological test battery. We also registered prior history of fatigue and mood disorders as well as occupational status and RTW. The patients experienced fatigue as being among their three most disabling symptoms and when characterizing their fatigue they emphasized the questionnaire items “low motivation,” “mental fatigue,” and “sensitivity to stress.” Fatigue due to exercise was their least bothersome aspect of fatigue and weight gain was associated with depressive symptoms rather than the severity of fatigue. Although there was a strong association between fatigue and mood disorders, especially for depression, the overlap was incomplete. Post-aSAH fatigue related to reduced HRQoL. RTW was remarkably low with only 10.3% of patients returning to their previous workload. Fatigue was not related to cognitive functioning or neurological status. Although there was a strong association between fatigue and depression, the incomplete overlap supports the notion of these two being distinct constructs. Moreover, post-aSAH fatigue can exist without significant neurological or cognitive impairments, but is related to reduced HRQoL and contributes to the low rate of RTW.

Extreme precipitation events in Norway in all seasons are often linked to atmospheric rivers (AR). We show that during the period 1979–2018 78.5% of the daily extreme precipitation events in Southwestern Norway are linked to ARs, this percentage decreasing to 59% in the more northern coastal regions and ~40% in the inland regions. The association of extreme precipitation with AR occurs most often in fall for the coastal areas and in summer inland. All Norwegian regions experience stronger winds and 1–2°C increase of the temperature at 850 hPa during AR events compared to the climatology, the extreme precipitation largely contributing to the wet climatology (only considering rainy days) in Norway but also in Denmark and Sweden when the rest of Europe is dry. A cyclone is found nearby the AR landfall point in 70% of the cases. When the cyclone is located over the British Isles, as it is typically the case when ARs reach Southeastern Norway, it is associated with cyclonic Rossby wave breaking whereas when the ARs reach more northern regions, anticyclonic wave breaking occurs over Northern Europe. Cyclone-centered composites show that the mean sea level pressure is not significantly different between the eight Norwegian regions, that baroclinic interaction can still take place although the cyclone is close to its decay phase and that the maximum precipitation occurs ahead of the AR. Lagrangian air parcel tracking shows that moisture uptake mainly occurs over the North Atlantic for the coastal regions with an additional source over Europe for the more eastern and inland regions.