100 research outputs found
Mackerel egg investigations in the North Sea
This paper deals with the mackerel egg investigations in the North Sea
in 1982 and 1983. The egg production is estimated by a computerized
method. The confidence limits of the egg samples were estimated at
20-30%. The optimum future distribution of sampling effort in the
area is calculated according to Neyman allocation. A comparison of the
fecundity of mackerel from different areas measured by different
methods is done. The size of the North Sea spawning stock is estimated
based on the egg surveys and the fecundity studies
Activation of ERK1/2 by the human 5-HT7 serotonin receptors
Receptor tyrosine kinases (RTKs) activate the mitogen-activated protein (MAP) kinases called extracellular signal-regulated kinases 1 and 2 (ERK1/2) through a signaling cascade involving proteins such as Shc, Grb2, SOS, Ras, Raf-1 and MEK. Activation of ERK1/2 directs proliferation and differentiation in a wide array of cell types. G-protein-coupled receptors (GPCRs) of many types have been shown to activate the ERK cascade, but the complete mechanisms are yet to be elucidated. Gs-coupled receptors activate adenylyl cyclase (AC) leading to a rapid increase in cyclic AMP (cAMP), and the main targets for cAMP are protein kinase A (PKA) and the Exchange Protein directly Activated by cAMP (Epac) specific for the small G-protein Rap1. It has been proposed for the Gs-coupled Ăą2-adrenergic receptor that activation of ERK1/2 proceeds through Rap1 and B-Raf in a manner independent of Ras. However, for the human Gs-coupled serotonin receptors 5-HT4(b) and 5-HT7(a) it has been shown that ERK1/2 activation occurs independently of Rap1, relying instead on PKA and Ras. In this project we have explored various signaling mechanisms originating from the human Gs-coupled 5-HT7 serotonin receptors, with particular interest in the mechanisms of activation of ERK1/2. We demonstrate the activation of ERK1/2 in HEK293 cells transfected with 5-HT7(b) and 5-HT7(d) receptors subsequent to stimulation with serotonin. For the 5-HT7(b) receptors, we show that the observed activation of ERK1/2 is dependent on cAMP and Ras, but not on Epac and Rap1. Furthermore, direct cytosolic calcium measurements have shown that treatment with serotonin leads to a rapid but transient elevation in intracellular calcium in HEK293 cells stably transfected with 5-HT7(b) receptors, and the observed phosphorylation of ERK1/2 is mediated, at least partly, through a calcium-dependent pathway. We show that HEK293 cells endogenously express the Ras specific, Ca2+/calmodulin-dependent guanine nucleotide exchange factor Ras-GRF1. Ras-GRF1 becomes phosphorylated
subsequent to 5-HT stimulation of 5-HT7(b) receptors, and it has previously been demonstrated that this phosphorylation enhances its towards Ras. This indicates that Ras-GRF1 has a role in the observed Ras-dependent activation of ERK1/2 mediated through 5-HT7(b) receptors
Remote sensing of aerosols in the Arctic for an evaluation of global climate model simulations
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License, which permits use and distribution in any medium, provided the original work is properly cited, the use is non-commercial and no modifications or adaptations are madeIn this study Moderate Resolution Imaging Spectroradiometer (MODIS) Aqua retrievals of aerosol optical thickness (AOT) at 555 nm are compared to Sun photometer measurements from Svalbard for a period of 9 years. For the 642 daily coincident measurements that were obtained, MODIS AOT generally varies within the predicted uncertainty of the retrieval over ocean (ÎAOT=±0.03±0.05·AOT). The results from the remote sensing have been used to examine the accuracy in estimates of aerosol optical properties in the Arctic, generated by global climate models and from in situ measurements at the Zeppelin station, Svalbard. AOT simulated with the Norwegian Earth System Model/Community Atmosphere Model version 4 Oslo global climate model does not reproduce the observed seasonal variability of the Arctic aerosol. The model overestimates clear-sky AOT by nearly a factor of 2 for the background summer season, while tending to underestimate the values in the spring season. Furthermore, large differences in all-sky AOT of up to 1 order of magnitude are found for the Coupled Model Intercomparison Project phase 5 model ensemble for the spring and summer seasons. Large differences between satellite/ground-based remote sensing of AOT and AOT estimated from dry and humidified scattering coefficients are found for the subarctic marine boundary layer in summer.Peer reviewe
Evaluation of âGLAMEPSââa proposed multimodel EPS for short range forecasting
Grand Limited Area Model Ensemble Prediction System (GLAMEPS) is prepared for pan-European, short-range probabilistic numerical weather prediction of fine synoptic-scale, quasi-hydrostatic atmospheric flows. Four equally sized ensembles are combined: EuroTEPS, a version of the global ECMWF EPS with European target; AladEPS, a downscaling of EuroTEPS using the ALADIN model; HirEPS_K and HirEPS_S, two ensembles using the HIRLAM
model nested into EuroTEPS including 3DVar data-assimilation for two control forecasts. A 52-member GLAMEPS thus samples forecast uncertainty by three analysed initial states combined with 12 singular vector-based perturbations, four different models and the stochastic physics tendencies in EuroTEPS. Over a 7-week test period in winter 2008, GLAMEPS produced better results than ECMWFâs EPS with 51 ensemble members. Apart from spatial resolution, the improvement is due to the multimodel combination and to a smaller extent the dedicated EuroTEPS. Ensemble
resolution and reliability are both improved. Combining uncalibrated ensembles is seen to produce a better combined ensemble than the best single-model ensemble of the same size, except when one of the single-model ensembles is considerably better than the others. Bayesian Model Averaging improves reliability, but needs further elaboration to account for geographical variations. These conclusions need to be confirmed by long-period evaluations
Pseudomonas aeruginosa contamination of mouth swabs during production causing a major outbreak
BACKGROUND: In 2002 we investigated an outbreak comprising 231 patients in Norway, caused by Pseudomonas aeruginosa and linked to the use of contaminated mouth swabs called Dent-O-Sept. Here we describe the extent of contamination of the swabs, and identify critical points in the production process that made the contamination possible, in order to prevent future outbreaks. METHODS: Environmental investigation with microbiological examination of production, ingredients and product, molecular typing of bacteria and a system audit of production. RESULTS: Of the 1565 swabs examined from 149 different production batches the outbreak strain of P. aeruginosa was detected in 76 swabs from 12 batches produced in 2001 and 2002. In total more than 250 swabs were contaminated with one or more microbial species. P. aeruginosa was detected from different spots along the production line. The audit revealed serious breeches of production regulations. Health care institutions reported non-proper use of the swabs and weaknesses in their purchasing systems. CONCLUSION: Biofilm formation in the wet part of the production is the most plausible explanation for the continuous contamination of the swabs with P. aeruginosa over a period of at least 30 weeks. When not abiding to production regulations fatal consequences for the users may ensue. For the most vulnerable patient groups only documented quality-controlled, high-level disinfected products and items should be used in the oropharynx
Effect of caudal epidural steroid or saline injection in chronic lumbar radiculopathy: multicentre, blinded, randomised controlled trial
Objective To assess the efficacy of caudal epidural steroid or saline
injection in chronic lumbar radiculopathy in the short (6 weeks),
intermediate (12 weeks), and long term (52 weeks).
Design Multicentre, blinded, randomised controlled trial.
Setting Outpatient multidisciplinary back clinics of five Norwegian
hospitals.
Participants Between October 2005 and February 2009, 461 patients
assessed for inclusion (presenting with lumbar radiculopathy >12 weeks).
328 patients excluded for cauda equina syndrome, severe paresis,
severe pain, previous spinal injection or surgery, deformity, pregnancy,
ongoing breast feeding, warfarin therapy, ongoing treatment with
non-steroidal anti-inflammatory drugs, body mass index >30, poorly
controlled psychiatric conditions with possible secondary gain, and
severe comorbidity.
Interventions Subcutaneous sham injections of 2 mL 0.9% saline,
caudal epidural injections of 30 mL 0.9% saline, and caudal epidural
injections of 40 mg triamcinolone acetonide in 29 mL 0.9% saline.
Participants received two injections with a two week interval.
Main outcome measures Primary: Oswestry disability index scores.
Secondary: European quality of life measure, visual analogue scale
scores for low back pain and for leg pain.
Results Power calculations required the inclusion of 41 patients per
group. We did not allocate 17 of 133 eligible patients because their
symptoms improved before randomisation. All groups improved after
the interventions, but we found no statistical or clinical differences
between the groups over time. For the sham group (n=40), estimated
change in the Oswestry disability index from the adjusted baseline value
was â4.7 (95% confidence intervals â0.6 to â8.8) at 6 weeks, â11.4
(â6.3 to â14.5) at 12 weeks, and â14.3 (â10.0 to â18.7) at 52 weeks.
For the epidural saline intervention group (n=39) compared with the
sham group, differences in primary outcome were â0.5 (â6.3 to 5.4) at
6 weeks, 1.4 (â4.5 to 7.2) at 12 weeks, and â1.9 (â8.0 to 4.3) at 52
weeks; for the epidural steroid group (n=37), corresponding differences
were â2.9 (â8.7 to 3.0), 4.0 (â1.9 to 9.9), and 1.9 (â4.2 to 8.0). Analysis
adjusted for duration of leg pain, back pain, and sick leave did not change
this trend.
Conclusions Caudal epidural steroid or saline injections are not
recommended for chronic lumbar radiculopathy
Trends in extreme weather events in Europe: implications for national and European Union adaptation strategies
This report, based on a comprehensive collection of scientific data from the last 20 years, provides a rallying call for Europeâs policy makers to come together to devise common strategies to help mitigate the physical, human and economic costs of the rising number of extreme weather events in Europe, such as extreme heat and cold, extremes of precipitation, storms, winds and surges, and drought. Highlights refer to the nature of the evidence for climate-driven changes in extreme weather in the past, the potential impact of further climate change in altering the pattern of these extremes, and possible adaptation strategies for dealing with extreme weather impacts.
It first provides information on extreme weather events and trends in recent decades as well as related impacts upon society. It is followed by an introduction to the scientific background on global warming and weather extremes, and the projections of future trends of meteorological extreme events that emerge from climate models under various scenarios of future greenhouse gas emissions. Finally, approaches to adaptation are introduced and recommendations provided. Readers wishing to obtain full source details for the figures, tables and references are recommended to consult the full report, which also includes more detailed analyses of the climatic conditions in various sub-regions of the EU
Research needs and data gaps of importance for food safety and protection of biodiversity. Summary report from VKMâs scientific opinions in the period 2005 - 2015.
Related version: VKM Report 2016: 48 : https://vkm.no/download/18.7e19596115dabec04172717/1501849448865/30664700ba.pdfThe aim of the present report is to highlight research needs and data gaps that are of future importance for food safety and protection of biodiversity. The Norwegian Scientific Committee for Food Safety (VKM) produces and communicates scientific opinions, i.e. risk-and risk-benefitassessments, with the main goal of securing food safety and protection of biodiversity
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