74 research outputs found
Methylation of PP2A - Effects of heat stress on gene expression and phenotype of Arabidopsis thaliana
The possible connection between protein phosphatase 2A (PP2A) and heat stress performance was explored in Arabidopsis thaliana by comparing wild type (WT) with a lcmt1 knockout mutant. In healthy organisms the enzyme leucine carboxyl methyl transferase 1 (LCMT1) is responsible for methylating PP2A. A lcmt1 mutant will not be able to methylate PP2A, and although the importance of methylation is poorly understood it has been shown to have a big effect under stress.
The plants were grown in Petri dishes and in soil, exposed to various lengths of heat stress and any phenotype differences were observed. Certain differences in gene response were also observed by the use of real-time PCR.
Results showed healthy growth, but with some differences in the mutant lcmt1 compared with WT under normal condition. However, under stress WT would outperform lcmt1 with the difference becoming more clear with increased stress.
The expression levels of different genes were explored, and differences were found. Quantification cycle (Cq) and relative quantification (RQ) was examined, and especially values for heat shock protein 90-1 (HSP90-1) and iron-regulated transporter 1 (IRT1) stood out. Values were examined after 0 h, 1 h and 24 h of heat stress. The results were clearest after 24 h, where WT showed the strongest deviation from the control with strongly increased expression for HSP90-1 and strongly decreased expression for IRT1 compared with the mutant lcmt1
Implementation, demonstration and validation of a user-defined wall-function for direct precipitation fouling in ANSYS Fluent
In a previous paper (Johnsen et al., 2015) and presentation (Johnsen et al.,
2016), we developed and demonstrated a generic modelling framework for the
modelling of direct precipitation fouling from multi-component fluid mixtures
that become super-saturated at the wall. The modelling concept involves the
1-dimensional transport of the fluid species through the turbulent boundary
layer close to the wall. The governing equations include the Reynolds-averaged
(RANS) advection-diffusion equations for each fluid species, and the axial
momentum and energy equations for the fluid mixture. The driving force for the
diffusive transport is the local gradient in the species' chemical potential.
Adsorption mechanisms are not modelled per se, but the time-scale of adsorption
is reflected in the choice of Dirichlet boundary conditions for the depositing
species, at the fluid-solid interface.
In this paper, the modelling framework is implemented as a user-defined
function (UDF) for the CFD software ANSYS Fluent, to act as a wall boundary
condition for mass-transfer to the wall. The subgrid, 1-dimensional formulation
of the model reduces the computational cost associated with resolving the fine
length-scales at which the boundary-layer mass transfer is determined, and
allows for efficient modelling of industry-scale heat exchangers suffering from
fouling.
The current paper describes the modelling framework, and demonstrates and
validates its applicability in a simplified 2D heat exchanger geometry
(experimental and detailed CFD modelling data by P\"a\"akk\"onen et al. (2012,
2016)). By tuning the diffusivity, only, good agreement with the experimental
data and the detailed CFD model was obtained, in terms of area-averaged
deposition rates.Comment: 12th International Conference on CFD in Oil & Gas, Metallurgical and
Process Industries, SINTEF, Trondheim, NORWAY, May 30th - June 1st, 2017, 9
pages, 9 figure
Naturindeks Norge – Videreutvikling av kunnskapsgrunnlaget for åpent lavland: fase 3. Evaluering av metodikk for kartlegging og registrering av biologisk mangfold og miljøvariabler i semi‐naturlig eng. Underveisrapport.
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Norway and Fisheries Globalisation: Challenges and Policy Priorities
Norway is probably among the most obvious beneficiaries of globalisation, mainly because of the rich natural resources, skilled labour, advanced technology products and strong institutions. The fishing industry has been on the forefront in adjusting to new challenges and seeking the potential gains of economic integration, liberalisation and deregulation. The international orientation and exposure to fluctuations and rapid change have been key features of the industry for centuries, mainly due to extensive export and trade. Consequently the fishing industry is well accustomed to the drivers and forces of globalisation. The national
windfall benefits arising from globalisation do however add further pressure on the fishing industry in terms of continuous efficiency improvements, cost increases and greater competition. Given the limited nature of fisheries resources, regulation is a prerequisite to ensure sustainability, economic rents and national policy objectives. On the other hand the regulatory set-up should take into account the gains which arise from deregulation and greater flexibility, and empower the industry to maintain its competitiveness. Evidently both industry and government are faced with risks and challenges and the key concern is how to cope with these while at the same time reaping the benefits. Within the context of fisheries globalisation
issues like global governance and enforcement, IUU-fishing, level playing field, market access, food prices, foreign investments, relocation and fragmentation of production carry great importance. This paper explores the key challenges to the management of fisheries and how they are addressed through Norwegian policy priorities
Fødselsomsorgen kan bli bedre
Til tross for en god fødselsomsorg i Norge skjer det uønskede hendelser med alvorlig utfall for mor og/eller barn. I media kan man jevnlig lese om alvorlige hendelser i forbindelse med fødsel, der tema ofte er dødsfall eller skade som følge av manglende eller feil helsehjelp. Disse historiene gjør inntrykk.
Det er ikke bare den berørte familien som blir hardt rammet, det er også de involverte fødselshjelperne. Den psykiske belastningen kan for noen være så stor at de ikke ønsker å arbeide videre i fødselsomsorgen (1). Omkring halvdelen av slike uønskede hendelser kunne vært unngått hvis fødselen hadde blitt håndtert annerledes (2–4). Hva er det som kan gå galt under fødsel, og hvorfor ser det ut til at samme type hendelser skjer igjen og igjen
How common is substandard obstetric care in adverse events of birth asphyxia, shoulder dystocia and postpartum hemorrhage? Findings from an external inspection of Norwegian maternity units
Introduction - The Norwegian Board of Health Supervision inspects healthcare institutions to ensure safety and quality of health and welfare services. A planned inspection of 12 maternity units aimed to investigate the practice of obstetric care in the case of birth asphyxia, shoulder dystocia and severe postpartum hemorrhage.
Material and methods - The inspection was carried out at two large, four medium and six small maternity units in Norway in 2016 to investigate adverse events that occurred between 1 January and 31 December 2014. Six of them were selected as control units. The Norwegian Board of Health Supervision searched the Medical Birth Registry of Norway to identify adverse events in each of the categories and then requested access to the medical records for all patients identified. Information about guidelines, formal teaching and simulation training at each unit was obtained by sending a questionnaire to the obstetrician in charge of each maternity unit.
Results - The obstetric units inspected had 553 serious adverse events of birth asphyxia, shoulder dystocia or severe postpartum hemorrhage among 17 323 deliveries. Twenty-nine events were excluded from further analysis due to erroneous coding or missing data in the patients’ medical records. We included 524 cases (3.0% of all deliveries) of adverse events in the final analysis. Medical errors caused by substandard care were present in 295 (56.2%) cases. There was no difference in the prevalence of substandard care among the maternity units according to their size. Surprisingly, we found significantly fewer cases with substandard care in the units which the supervisory authorities considered particularly risky before the inspection, compared with the control units. Seven of the 12 units had regular formal teaching and training arrangements for obstetric healthcare personnel as outlined in the national guidelines.
Conclusions - Prevalence of adverse events was 3% and similar in all maternity units irrespective of their size. A breach in the standard of care was observed in 56.2% of cases and almost half of the maternity units did not follow national recommendations regarding teaching and practical training of obstetric personnel, suggesting that they should focus on implementing guidelines and training their staff
Loss of LEUCINE CARBOXYL METHYLTRANSFERASE 1 interferes with metal homeostasis in Arabidopsis and enhances susceptibility to environmental stresses
The biochemical function of LEUCINE CARBOXYL METHYLTRANSFERASE 1 (LCMT1) is to transfer a methyl group from the methyl donor S-adenosylmethionine (SAM) to the catalytic subunits of PROTEIN PHOSPHATASE 2A (PP2Ac), PP4 and PP6. This post-translational modification by LCMT1 is found throughout eukaryotes from yeast to animals and plants, indicating that its function is essential. However, Arabidopsis with knocked out LCMT1 still grows and develops almost normally, at least under optimal growth conditions. We therefore proposed that the presence of LCMT1 would be important under non-optimal growth conditions and favoured plant survival during evolution. To shed light on the physiological functions of plant LCMT1, phenotypes of the lcmt1 mutant and wild type Arabidopsis were compared under various conditions including exposure to heavy metals, variable chelator concentrations, and increased temperature. The lcmt1 mutant was found to be more susceptible to these environmental changes than wild type and resulted in poor growth of seedlings and rosette stage plants. Element analysis of rosette stage plants mainly showed a difference between the lcmt1 mutant and wild type regarding concentrations of sodium and boron, two-fold up or halved, respectively. In both lcmt1 and wild type, lack of EDTA in the growth medium resulted in enhanced concentration of copper, manganese, zinc and sulphur, and especially lcmt1 growth was hampered by these conditions. The altered phenotype in response to stress, the element and mRNA transcript analysis substantiate that LCMT1 has an important role in metal homeostasis and show that functional LCMT1 is necessary to prevent damages from heat, heavy metals or lack of chelator.publishedVersio
The Psychological and HRQoL related Aftermaths of Extra Corporeal Membrane Oxygenation Treatment: A Cross‐Sectional Study
Objectives: To assess symptoms of post-traumatic stress disorder, anxiety, depression and health related quality of life in a sample of adult patients treated with veno-arterial extracorporeal membrane oxygenation.
Design and setting: This is a cross-sectional study. The population were all patients discharged (2008–2018) from a thoracic surgical intensive ward at a tertiary university hospital in Norway. A sample of 20 patients was recruited.
Main outcome measures: Symptoms of post-traumatic stress disorder were assessed using Impact of Events Scale-Revised, while symptoms of depression and anxiety were assessed using Hospital Anxiety and Depression Scale. RAND 36-Item Short Form Health Survey was applied to measure health-related quality of life.
Results: Symptoms of post-traumatic stress disorder were reported by 40% of the participants. Twenty percent reported symptoms of depression and anxiety. Compared to the general population, participants reported poorer health-related quality of life on all domains, and significantly worse on the domains physical function, general health and social function.
Conclusion: Patients in our study reported symptoms of post-traumatic stress disorder, anxiety, depression and impaired health-related quality of life following treatment with veno-arterial extra corporeal membrane oxygenation. Addressing possible emotional and psychological distress could represent a potential major improvement in health care provided to this group. Further research is needed to incorporate prophylactic methods, such as identifying vulnerable patients and implement corresponding interventions, into clinical practice.publishedVersio
Cenozoic uplift and erosion of the Norwegian Barents Shelf – A review
Uplift and erosion are complex phenomena in terms of their governing processes, precise timing and exact magnitude. The intricate relationship between different geodynamic processes leading to uplift may increase uncertainties in estimating spatial and temporal patterns. Sediment distribution from uplifted (and eroded) topography and the corresponding paleoenvironmental reconstructions require reliable constrains. The Barents Shelf provides a unique arena to study uplift and erosion due to extensive seismic and well data attributed to high petroleum activity. This particular interest has led to a voluminous literature about this topic over the last three decades. Here, we present the current status of the Cenozoic uplift and erosion on the Norwegian Barents Shelf by reviewing the key terminology, its tectonic history and paleoenvironment, methods in quantifying uplift and erosion, as well as timing and possible mechanisms. Our new erosion maps show an increase in net erosion to the north and northeast that represents key underlying concepts, including tectonic (compression, rift-flank uplift, thermo-mechanical coupling, mantle dynamics, flexural/isostatic response) as well as magmatic and glacial processes. We have integrated pre-glacial and glacial net erosion using the mass balance method and added our results from sonic velocity, interval velocity and sandstone diagenesis methods to the new maps. This review shows that discrepancies of net erosion estimates from different methods are on the order of 500 m. Finally, we identify research gaps for future studies, with implications for the Barents Shelf and other uplifted basins worldwide
Discovery of shale gas in organic rich Jurassic successions, Adventdalen, Central Spitsbergen, Norway
Thermogenic dry gas flowed from Jurassic sections in the DH5R research well drilled onshore in Adventdalen, central Spitsbergen, Arctic Norway. The DH5R gas originates from the organic-rich units of the mudstone-dominated Middle Jurassic to Lower Cretaceous Agardhfjellet Formation, which is the onshore equivalent to the Fuglen Formation and the prolific oil and gas generating Hekkingen Formation in the southern Barents Shelf. Low-permeable, low-porosity sandstones from the Upper Triassic De Geerdalen Formation of the neighbouring DH4 well were oil-stained and gas was also collected from this interval. Gas from the two stratigraphic intervals have different compositions; the gas from the Agardhfjellet Formation is drier and isotopically heavier than the gas from the Upper Triassic succession. Both gases originated from source rocks of maturity near the end of the oil window (1.1 < Ro < 1.4% Ro). Maceral analyses of the Agardhfjellet Formation indicate that the more silty parts contain a high percentage of vitrinite-rich type III kerogen, whereas the clay-dominated parts are rich in liptinitic type II kerogen. The Agardhfjellet Formation has therefore the potential to generate both oil and gas. Several simulations based on pressure data and flow rates from the DH5R well were run to evaluate if the gas accumulation in the Agardhfjellet Formation is producible, i.e., can it be commercial shale gas. The models demonstrate how changes in the drainage area size and form, well types (vertical versus horizontal), number and length of induced fractures and thickness of the Agardhfjellet Formation affect gas production rates and producible volumes. Despite uncertainties in the input data, simulations indicate that the shale gas accumulation characterised in Adventdalen is producible. This gas can have major environmental benefits as an alternative for local power generation compared to coal.publishedVersio
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