Numerical simulations of submerged and pressurised X65 steel pipes – COMPLAS XII

While in service, pipelines may from time to time be exposed to impact loads from anchors or trawl gear. A lot of parameters influence the behaviour of the pipeline during impact, e.g. the diameter and thickness of the pipeline, the impactor’s mass and velocity, and of course the material used. Also potentially influencing the deformation pattern is the presence of surrounding water, which can be a difficult parameter to include experimentally. The pressurised contents of the pipeline can also be an influencing factor. To gain some insight into how the water and possible pressure inside the pipeline affect the global impact behaviour, numerical investigations have been carried out using FSI- techniques available in the explicit finite element code Europlexus. One case was set up for validation against available experimental data, and additional cases examined numerically the effect of including pressure and/or surrounding water. The simulations generally captured the deformation and load levels from the experiments well, and may be assumed to represent the events with reasonable accuracy. Adding internal pressure generally led to a higher peak load, and created a more localised deformation. Submerging the pipe in water seemed to be of minor importance with respect to global and local deformation, but this depended heavily on the FSI conditions. Other parameters than the surrounding water, which for design purposes may be omitted, appear to be more significant to the global and local response

Force-velocity profiling in athletes: Reliability and agreement across methods

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Correlation between gene expression and MRI STIR signals in patients with chronic low back pain and Modic changes indicates immune involvement

Disability and distress caused by chronic low back pain (LBP) lacking clear pathoanatomical explanations cause huge problems both for patients and society. A subgroup of patients has Modic changes (MC), identifiable by MRI as vertebral bone marrow lesions. The cause of such changes and their relationship to pain are not yet understood. We explored the pathobiology of these lesions using profiling of gene expression in blood, coupled with an edema-sensitive MRI technique known as short tau inversion recovery (STIR) imaging. STIR images and total RNA from blood were collected from 96 patients with chronic LBP and MC type I, the most inflammatory MC state. We found the expression of 37 genes significantly associated with STIR signal volume, ten genes with edema abundancy (a constructed combination of STIR signal volume, height, and intensity), and one gene with expression levels significantly associated with maximum STIR signal intensity. Gene sets related to interferon signaling, mitochondrial metabolism and defense response to virus were identified as significantly enriched among the upregulated genes in all three analyses. Our results point to inflammation and immunological defense as important players in MC biology in patients with chronic LBP.publishedVersio

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Correction to: Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

The original version of this article unfortunately contained a mistake

Prevalence, associated factors and outcomes of pressure injuries in adult intensive care unit patients: the DecubICUs study

Funder: European Society of Intensive Care Medicine; doi: http://dx.doi.org/10.13039/501100013347Funder: Flemish Society for Critical Care NursesAbstract: Purpose: Intensive care unit (ICU) patients are particularly susceptible to developing pressure injuries. Epidemiologic data is however unavailable. We aimed to provide an international picture of the extent of pressure injuries and factors associated with ICU-acquired pressure injuries in adult ICU patients. Methods: International 1-day point-prevalence study; follow-up for outcome assessment until hospital discharge (maximum 12 weeks). Factors associated with ICU-acquired pressure injury and hospital mortality were assessed by generalised linear mixed-effects regression analysis. Results: Data from 13,254 patients in 1117 ICUs (90 countries) revealed 6747 pressure injuries; 3997 (59.2%) were ICU-acquired. Overall prevalence was 26.6% (95% confidence interval [CI] 25.9–27.3). ICU-acquired prevalence was 16.2% (95% CI 15.6–16.8). Sacrum (37%) and heels (19.5%) were most affected. Factors independently associated with ICU-acquired pressure injuries were older age, male sex, being underweight, emergency surgery, higher Simplified Acute Physiology Score II, Braden score 3 days, comorbidities (chronic obstructive pulmonary disease, immunodeficiency), organ support (renal replacement, mechanical ventilation on ICU admission), and being in a low or lower-middle income-economy. Gradually increasing associations with mortality were identified for increasing severity of pressure injury: stage I (odds ratio [OR] 1.5; 95% CI 1.2–1.8), stage II (OR 1.6; 95% CI 1.4–1.9), and stage III or worse (OR 2.8; 95% CI 2.3–3.3). Conclusion: Pressure injuries are common in adult ICU patients. ICU-acquired pressure injuries are associated with mainly intrinsic factors and mortality. Optimal care standards, increased awareness, appropriate resource allocation, and further research into optimal prevention are pivotal to tackle this important patient safety threat

Provenance of the Asker Group, Oslo Rift : A detrital zircon U-Pb and Lu-Hf study

To identify possible protosources for the Asker Group 573 in situ LA-MC-ICPMS uranium-lead and 509 lutetium-hafnium analyses were performed on detrital zircon grains from seven samples. The samples from the Kolsås and Skaugum Formations did not yield enough zircons (2 and 5, respectively) to be statistically viable, while for each of the five other samples, where three belong to the Tanum formation and two were taken from an area where no formational subdivision has been done, ∼ 100 zircon grains were analyzed. Major peaks and age clusters in the recorded 313 ± 4 to 2844 ± 14 Ma age span coincides with virtually every significant period of magmatism in Fennoscandia – including Archean, Svecofennian, TIB, Gothian, Sveconorwegian and Caledonian magmatism. This is also confirmed by the initial 176Hf/177Hf ratios. One major peak at c. 350 Ma does not correspond with any known magmatism in Fennoscandia, and is thus likely from the Variscides of Central Europe or the British Isles. Comparison of the recorded data with U-Pb and Lu-Hf data from the Ringerike Group and the Orsa sandstone suggests that the bulk zircon detritus of the Asker Group were derived from recycled Silurian sandstone cover sequences outside the Oslo Rift area, with a significant contribution from the Variscan mountains

Position technologies for internet connected mobile terminals, offering location based audio services

The company Infotain wishes to offer location based audio guiding at museums. They wish that this audio is going to be available through the visitor’s mobile phone. However, to be able to offer location based audio guiding a suitable positioning technology for mobile phones has to be found. Therefore the purpose of this thesis is to gather information about the technologies that can be used for location based information. After the technologies have been thoroughly examined we have to give Infotain a recommendation about what technology seems to best satisfy the demands. Important factors in evaluating the technologies are accuracy, response time, infrastructure power needs, and the ability to relocate site infrastructure. The seven technologies we found suitable are GPS, Mobile positioning, A-GPS, WLAN, Bluetooth, NFC and 2D barcodes. The two technologies NFC and 2D Barcodes were found the most promising as they satisfied the requirements to a high degree. Therefore these two were included in the testing phase. The testing was designed to simulate the situations a user of the guiding service could experience. Key factors recorded during the testing were time used and number of key strokes used. These results assisted in the choosing of a technology as they give a good picture of how the different technologies function. Based on its independence from electricity, its high accuracy, low response time and ease of site relocation, QR Codes was recommended as the most suitable technology

Phase-Field Modelling of Precipitation Mechanisms in Al-Mg-Si Alloys

Denne masteravhandlingen studerer utfellingsprosessen av β′′ utfellinger under kunstig eldning av aluminiumslegeringer i 6xxx-serien ved å benytte seg av fase-felt metoden. I løpet av de siste to tiårene har det blitt utført eksperimentelle studier der et eksternt felt ble satt på over en legeringsprøve av en aluminiumslegering samtidig som prøven var under kunstig eldning. Disse studiene oppdaget at legeringsprøvene oppnådde høyere maksimal styrke og raskere eldning under denne behandlingen. Arbeidet i denne avhandlingen ser på effekten av elektronvind på mikrostrukturen, forårsaket av at det blir satt på en elektrisk likestrøm gjennom legeringsprøven. Bidraget fra elastisk tøyning som følge av at gitterstrukturen til β′′ utfellingene passer dårlig inn i aluminiumsgitteret blir også lagt til i fase-felt modellen for å oppnå den typiske nål-formen til disse utfellingene. Det blir beregnet en karakteristisk tidsskala for diffusjonen av temperatur i mikrostrukturen som kommer frem til at det tar t = 156 ps å propagere en temperaturfront 100 nm, og dette indikerer at temperatursvingninger kan ses bort fra i modellering av mikrostrukturen. Simuleringsresultatene tilknyttet systemet med påført elektriske likestrøm over legeringsprøven oppnår ikke de samme utviklingsmekanismene i mikrostrukturen som har blitt sett i eksperimentelle undersøkelser av lignende systemer. Dette kan indikere at bidraget fra elektronvinden utgjør lite i forhold til andre utviklingsmekanismer i legeringer