185 research outputs found

    Application of Fiber Optic Technology in Reservoir Monitoring

    Get PDF
    The purpose of this thesis was to gain an overview of fields of application of fiber optic technology in reservoir monitoring, how such a measurement system is operated, and challenges that can occur. For automated and integrated processes in the exploration and production of hydrocarbons, the information available before, during, and after operations is of great value. Where to place wells and templates, at which rate and when production and injection is to take place are just a few of the decisions in such processes. Fiber optic technology which is common in reservoir monitoring tools in a production well, is also used for seismic and monitoring of the subsurface and pipelines along the seabed. Fiber optic measurement systems are of great value thanks to real-time data, which are an advantage in decisions to be made on short notice. By implementing fiber optic sensing elements along a wellbore, from the reservoir section and up to the surface, well intervention operations, testing of downhole safety equipment, well integrity assurance, and an active reservoir management on drainage and injection strategies can be optimized and profitability maximized. With in-well fiber optics already in place, they can be used for various operations. From cementing a liner, reservoir monitoring, and fluid characterization, to measuring strain and conditions of downhole equipment. Published papers, course material and equipment from Weatherford, discussion with field specialists, and personal experience have been the basis of the thesis. It was successfully demonstrated how a bad splice affects the optical power transmitted through a fiber optic cable, that attenuation on the emitted light has a boundary, and how important a test of an entire measurement system before operations is. The installations by Equinor at the Johan Sverdrup field are a good example of benefiting from implementation of technology from the start of development. The digitalization of the green field is part of their high ambition of a 70 % recovery. Fiber optics are a great choice of measurement systems for reservoir monitoring with many sensing elements already available in today’s market, and will most likely be a preferred choice for monitoring many wells and reservoirs in the years to come

    Hva fremmer mestring til tross for motstand? En studie om seksuelt overgrep i barndommen

    Get PDF
    Foreliggende studie undersøker hva voksne utsatt for seksuelle overgrep i barndommen opplever som hjelpsomt for mestring. Data var erfaringer rapportert fra brukere av Støttesenteret for Incest og Seksuelle Overgrep (SMISO) og foregikk ved at besøkende fylte ut anonymiserte spørreskjema som omhandlet temaet. Totalt 25 deltakere ble med i studien. En mixed-methods design med fortolkende fenomenologisk analyse og deskriptiv statistikk ble benyttet for analyse. Studien viste alle personene gjorde aktive tiltak i forkant, under og/eller etter overgrep, i forsøk på å forhindre nye overgrep, redusere effekten av pågående overgrep og minimalisere ettervirkningene. Dette gjorde de ut fra hvilke strategier som de opplevde som mulige få til i aktuell situasjon. Sosial støtte i form av informativ og emosjonell ble ansatt som den mest hjelpsomme mestringsstrategien. Studien viser at økt kunnskap om seksuelle overgrep i barndommen og et større fokus på hjelpsomme faktorer vil være av stor betydning som forebyggende og behandlende tiltak

    Mortality in the rockpool shrimp Palaemon elegans following long-term exposure to low doses of the anti-parasitic drug Teflubenzuron

    Get PDF
    Anti-parasitic drugs used to control sea lice infestations in the salmonid aquaculture industry are a growing environmental concern due to their potential impacts on non-target crustacean species. This study examined the lethal effects of teflubenzuron, a common in-feed pharmaceutical drug used on Norwegian salmon farms, on a non-target species, rockpool shrimp Palaemon elegans, following an extended exposure period. The standard daily dose for treating salmon is 10 µg teflubenzuron g-1 fish. Adult shrimp were fed 1 of 6 low doses of teflubenzuron (0, 0.0025, 0.005, 0.05, 0.094, 0.188 and 1.88 µg g-1) twice a week for a period of 66 d. Cumulative mortality reached 15, 27, 82 and 100% amongst shrimp exposed to the highest treatment groups (0.05, 0.094, 0.188 and 1.88 µg g-1, respectively). Cumulative mortality amongst shrimp exposed to the 2 lowest teflubenzuron doses and control feed was low (5%). Dose response curves based on measured concentrations within the shrimp were used to calculate a series of lethal threshold concentrations (LCx). The LC5, LC50 and LC90 concentrations of teflubenzuron causing low, median and high levels of mortality in rockpool shrimp were estimated to be 1.2, 18.4 and 150.6 ng g-1, respectively. These concentrations are similar to those reported in wild crustacean species, including shrimp species in the vicinity of Norwegian fish farms, both during and after teflubenzuron medication, suggesting that exposure to low doses of this compound can pose a significant risk to wild shrimp populations.publishedVersio

    Distribution and Persistence of Diflubenzuron and Teflubenzuron in the Marine Environment Around Salmonid Aquaculture Facilities

    Get PDF
    To achieve a sustainable salmonid aquaculture industry, the environmental impacts of chemicals used to treat sea lice (Caligidae) infestations need to be considered. Our ability to assess the risks associated with these treatments in relation to human and wildlife health is limited by the lack of information on their concentrations in marine coastal environments. Diflubenzuron and teflubenzuron are chitin synthesis inhibiting insecticides frequently used to treat sea lice infestations on Norwegian salmon farms. In the present study, the distribution, persistence and bioaccumulation of both compounds were assessed in marine sediments and benthic macrofauna collected at four Norwegian aquacultures sites. Both compounds were detected in sediments sampled at 30–1400 m from the selected farms and 8–22 months after the last treatments took place. Diflubenzuron was detected above the limit of quantification (LOQ) in 76% of sediment samples and measured levels ranged between 2.4 and 257 μg/kg dry weight (dw). Teflubenzuron was detected above the LOQ in 92% of sediment samples, at concentrations ranging between 1.3 and 3474 μg/kg dw. In all samples where diflubenzuron and teflubenzuron were detected, the measured levels exceeded the Norwegian environmental quality standards (EQSsediment; 0.2 and 0.0004 μg/kg dw, respectively), indicating that these compounds may pose a risk to benthic marine species living near fish farms. Both compounds were detected in wild fauna collected near the selected aquaculture sites with measured residue levels in the low micro-gramme per kilogramme wet weight range. The residue levels detected in economically important species caught for human consumption, such as pink shrimp (Pandalus montagui) and Norway lobster (Nephrops norvegicus), were substantially lower than biota EQS’s and maximum residue limits (MRL) set by the EU for salmon tissue. Further studies are needed to fully understand the ecological impacts of these compounds in the marine environment, with the potential for lethal and sub-lethal effects to occur in non-target organisms following chronic exposures.publishedVersio

    Vil sykepleieres økt kunnskap innen deeskaleringsteknikker kunne bidra til å redusere bruken av mekanisk tvang?

    Get PDF
    Bakgrunn Psykisk lidelse er noe som kan ramme hvem som helst, og føre til store belastninger. I 2018 mottok kontrollkommisjonen ett hundre og sekstien pasientklager fra personer utsatt for kortvarig fastholdning og mekaniske tvangsmidler. Det er nødvendig å undersøke muligheten for å redusere bruken av mekaniske tvangsmidler, og samtidig belyse bruken av deeskaleringsteknikker og effekten opplæring og kunnskap innen dette kan ha i utageringssituasjoner. Hensikt Oppgavens hensikt er å undersøke om økt kunnskap innen deeskalering vil bidra til å redusere bruken av mekanisk tvang, og hvilke faktorer som vil påvirke dette. Metode Vi har benyttet en integrativ litteraturstudie som metode, der vi har analysert fire forskningsartikler. Disse artiklene satt sammen med relevante oversiktsartikler danner grunnlag for vår besvarelse. Oppgaven besvares med et sykepleieperspektiv. Resultat Resultatene viste at sykepleiere var skuffet over at deeskaleringsteknikker ble sett på som bevisbasert praksis. Det ble avdekket at deltagerne la til rette for en forforståelse om at effekten av deeskaleringsteknikker var avhengig av at sykepleierne hadde en relasjon til pasienten. Funnene viser til at deeskalering har effekt i praksis, men at sykepleiere ikke har tillit til teknikkene dersom risikoen for vold er større. Egen angst i utageringssituasjoner ble identifisert som en viktig faktor for hvorfor det ble tatt i bruk mer restriktive tiltak fremfor deeskalering. Opplæringen innen deeskaleringsteknikker førte også til minimal innvirkning på sykepleieres evne til å regulere egne følelser av angst

    Vil sykepleiers økt kunnskap innen deeskaleringsteknikker kunne bidra til å redusere bruken av mekanisk tvang?

    Get PDF
    Bakgrunn Psykisk lidelse er noe som kan ramme hvem som helst, og føre til store belastninger. I 2018 mottok kontrollkommisjonen ett hundre og sekstien pasientklager fra personer utsatt for kortvarig fastholdning og mekaniske tvangsmidler. Det er nødvendig å undersøke muligheten for å redusere bruken av mekaniske tvangsmidler, og samtidig belyse bruken av deeskaleringsteknikker og effekten opplæring og kunnskap innen dette kan ha i utageringssituasjoner. Hensikt Oppgavens hensikt er å undersøke om økt kunnskap innen deeskalering vil bidra til å redusere bruken av mekanisk tvang, og hvilke faktorer som vil påvirke dette. Metode Vi har benyttet en integrativ litteraturstudie som metode, der vi har analysert fire forskningsartikler. Disse artiklene satt sammen med relevante oversiktsartikler danner grunnlag for vår besvarelse. Oppgaven besvares med et sykepleieperspektiv. Resultat Resultatene viste at sykepleiere var skuffet over at deeskaleringsteknikker ble sett på som bevisbasert praksis. Det ble avdekket at deltagerne la til rette for en forforståelse om at effekten av deeskaleringsteknikker var avhengig av at sykepleierne hadde en relasjon til pasienten. Funnene viser til at deeskalering har effekt i praksis, men at sykepleiere ikke har tillit til teknikkene dersom risikoen for vold er større. Egen angst i utageringssituasjoner ble identifisert som en viktig faktor for hvorfor det ble tatt i bruk mer restriktive tiltak fremfor deeskalering. Opplæringen innen deeskaleringsteknikker førte også til minimal innvirkning på sykepleieres evne til å regulere egne følelser av angst

    Novel hybridization- and tag-based error-corrected method for sensitive ctDNA mutation detection using ion semiconductor sequencing

    Get PDF
    Circulating tumor DNA (ctDNA) analysis has emerged as a clinically useful tool for cancer diagnostics and treatment monitoring. However, ctDNA detection is complicated by low DNA concentrations and technical challenges. Here we describe our newly developed sensitive method for ctDNA detection on the Ion Torrent sequencing platform, which we call HYbridization- and Tag-based Error-Corrected sequencing (HYTEC-seq). This method combines hybridization-based capture with molecular tags, and the novel variant caller PlasmaMutationDetector2 to eliminate background errors. We describe the validation of HYTEC-seq using control samples with known mutations, demonstrating an analytical sensitivity down to 0.1% at > 99.99% specificity. Furthermore, to demonstrate the utility of this method in a clinical setting, we analyzed plasma samples from 44 patients with advanced pancreatic cancer, revealing mutations in 57% of the patients at allele frequencies as low as 0.23%.publishedVersio

    Interleukin-1-related activity and hypocretin-1 in cerebrospinal fluid contribute to fatigue in primary Sjögren’s syndrome

    Get PDF
    Background Fatigue is a common and sometimes debilitating phenomenon in primary Sjögren’s syndrome (pSS) and other chronic inflammatory diseases. We aimed to investigate how IL-1 β-related molecules and the neuropeptide hypocretin-1 (Hcrt1), a regulator of wakefulness, influence fatigue. Methods Hcrt1 was measured by radioimmunoassay (RIA) in cerebrospinal fluid (CSF) from 49 patients with pSS. Interleukin-1 receptor antagonist (IL-1Ra), IL-1 receptor type 2 (IL-1RII), IL-6, and S100B protein were measured by enzyme-linked immunosorbent assay (ELISA). Fatigue was rated by the fatigue visual analog scale (fVAS). Results Simple univariate regression and multiple regression analyses with fatigue as a dependent variable revealed that depression, pain, and the biochemical variable IL-1Ra had a significant association with fatigue. In PCA, two significant components were revealed. The first component (PC1) was dominated by variables related to IL-1β activity (IL-1Ra, IL-1RII, and S100B). PC2 showed a negative association between IL-6 and Hcrt1. fVAS was then introduced as an additional variable. This new model demonstrated that fatigue had a higher association with the IL-1β-related PC1 than to PC2. Additionally, a third component (PC3) became significant between low Hcrt1 concentrations and fVAS scores. Conclusions The main findings of this study indicate a functional network in which several IL-1β-related molecules in CSF influence fatigue in addition to the classical clinical factors of depression and pain. The neuropeptide Hcrt1 seems to participate in fatigue generation, but likely not through the IL-1 pathway.publishedVersio
    • …
    corecore