Strategisk analyse og verdsetjing av DNO

Vi har i denne utredninga føreteke ein strategisk rekneskapsanalyse og verdsetjing av DNO ASA, som er eit heilintegrert olje- og gasselskap. Gjennom den strategiske analysen avdekkja vi at oljebransjen har hatt ein bransjeorientert strategisk fordel dei seinare åra og at framtidsutsiktene framleis er lyse, men at det og er knytt vesentlig risiko til potensielle substituttar og intern rivalisering. Profitten og forventningane i bransjen er sterkt avhengig av oljeprisen til ei kvar tid. For DNO meinar vi det eksisterer interne ressursar som organisasjonsstruktur, kompetanse og omdøme som om dei vert forvalta rett kan gi dei ein varig strategisk fordel. Rekneskapsanalysen viste at selskapet både har god likviditet og soliditet, samt at rentabiliteten har vore god dei siste åra. Med bakgrunn i den strategisk rekneskapsanalysen utarbeida vi framtidsrekneskap og framtidsbalanse. Dette gav oss moglegheit til å foreta ei fundamental verdsetjing av DNO. Etter konvergering vart estimatet vårt målt opp mot børskursen og vi valte ein handlestrategi utifrå dette. Med vårt estimat på 47 pr aksje mot børskursen på 53 den 31.05.06 er vår tilråding å redusere behaldninga av DNO-aksjar. Sensitivitetsanalysen peikar på at det herskar stor uvisse i estimatet, særlig til forventningar om oljeprisen i framtida, og dette må ein ha med i tankane når ein vurderer handling

REBO - Bærekraftig oppdatering av etterkrigstidens boligblokker: Artikkelsamling fra Husbankens strategiske forskningsprogram REBO 2008-2012

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Plan Selection in Proton Therapy of Locally Advanced Prostate Cancer with Simultaneous Treatment of Multiple Targets

Purpose Intensity modulated proton therapy (IMPT) of locally advanced prostate cancer can spare the bowel considerably compared with modern photon therapy, but simultaneous treatment of the prostate (p), seminal vesicles (sv), and lymph nodes is challenging owing to day-to-day organ motion and range uncertainties. Our purpose was, therefore, to generate a plan library for use in adaptive IMPT to mitigate these uncertainties. Methods and Materials We retrospectively included 27 patients with a series of computed tomography scans throughout their treatment representing day-to-day variation. In 18 of the patients, target motion was analyzed using rigid shifts of prostate gold markers relative to bony anatomy. A plan library with different p and sv planning target volume (p/sv-PTV) positions was defined from the distribution and direction of these shifts. Delivery of IMPT using plan selection from the library was simulated for image guidance on bony anatomy, in the remaining patients and compared with nonadaptive IMPT. Results The plan library consisted of 3 small margin p/sv-PTVs: (1) p/sv-PTV shifted 1.5 systematic error (Σ) of the population mean in the anterior and cranial directions, (2) p/sv-PTV shifted 1.5Σ in the posterior and caudal directions, and (3) p/sv-PTV in the planning position. The conventional p/sv-PTV was also available for backup. Plan selection compared with nonadaptive IMPT resulted in a reduction of the rectum volume receiving 60 Gy relative biological effect (RBE) (V60GyRBE) from on average 12 mL to 9 mL. For the bladder the average V45GyRBE was reduced from 36% to 30%. Large and small bowel doses were also reduced, whereas target coverage was comparable or improved compared with nonadaptive IMPT. Conclusions Plan selection based on a population model of rigid target motion was feasible for all patients. Compared with conventional IMPT, plan selection resulted in significant dosimetric sparing of rectum and bladder without compromising target coverage.publishedVersio

Fine-scale spatial variation of northern shrimp and Atlantic cod across three Norwegian fjord systems and implications for management

The spatial complexity of coastal ecosystems represents a challenge for the management of inshore resources. Here we compared two large fjord systems in northern Norway that have been closed for all bottom trawling for 50 years to a fjord with continuous shrimp fishery with bottom trawls. No significant differences were found between fjords with and without commercial trawling in population density and stock composition of northern shrimp (Pandalus borealis) and their main predator, Atlantic cod (Gadus morhua). Shrimp density was instead linked with bottom depth, while shrimp size and stage composition as well as cod density were explained by seasonal effects and shrimp density. For shrimp, a large degree of the observed variation was captured by spatial correlation that could not be explained by other covariates. The results underline the complex ecology in heavily structured coastal habitats and indicate that coastal shrimp dynamics are shaped by an interplay of multiple ecological and environmental drivers, possibly in concert with local genetic adaptations. The substantial fine-scale spatial variation adds to the challenges of assessing and managing fisheries resources in these fjord ecosystems. Because shrimp are an important forage species, notably as prey for cod, there are potential management conflicts between rebuilding cod stocks and reopening closed shrimp trawling areas.publishedVersio

Implementation of a double scattering nozzle for Monte Carlo recalculation of proton plans with variable relative biological effectiveness

A constant relative biological effectiveness (RBE) of 1.1 is currently used in clinical proton therapy. However, the RBE varies with factors such as dose level, linear energy transfer (LET) and tissue type. Multiple RBE models have been developed to account for this biological variation. To enable recalculation of patients treated with double scattering (DS) proton therapy, including LET and variable RBE, we implemented and commissioned a Monte Carlo (MC) model of a DS treatment nozzle. The main components from the IBA nozzle were implemented in the FLUKA MC code. We calibrated and verified the following entities to experimental measurements: range of pristine Bragg peaks (PBPs) and spread-out Bragg peaks (SOBPs), energy spread, lateral profiles, compensator range degradation, and absolute dose. We recalculated two patients with different field setups, comparing FLUKA vs. treatment planning system (TPS) dose, also obtaining LET and variable RBE doses. We achieved good agreement between FLUKA and measurements. The range differences between FLUKA and measurements were for the PBPs within ±0.9 mm (83% ≤ 0.5 mm), and for SOBPs ±1.6 mm (82% ≤ 0.5 mm). The differences in modulation widths were below 5 mm (79% ≤ 2 mm). The differences in the distal dose fall off (D80%–D20%) were below 0.5 mm for all PBPs and the lateral penumbras diverged from measurements by less than 1 mm. The mean dose difference (RBE = 1.1) in the target between the TPS and FLUKA were below 0.4% in a three-field plan and below 1.4% in a four-field plan. A dose increase of 9.9% and 7.2% occurred when using variable RBE for the two patients, respectively. We presented a method to recalculate DS proton plans in the FLUKA MC code. The implementation was used to obtain LET and variable RBE dose and can be used for investigating variable RBE for previously treated patients.publishedVersio

Inter-patient variations in relative biological efectiveness for craniospinal irradiation with protons

Cranio-spinal irradiation (CSI) using protons has dosimetric advantages compared to photons and is expected to reduce risk of adverse effects. The proton relative biological effectiveness (RBE) varies with linear energy transfer (LET), tissue type and dose, but a variable RBE has not replaced the constant RBE of 1.1 in clinical treatment planning. We examined inter-patient variations in RBE for ten proton CSI patients. Variable RBE models were used to obtain RBE and RBE-weighted doses. RBE was quantified in terms of dose weighted organ-mean RBE (RBEd = mean RBE-weighted dose/mean physical dose) and effective RBE of the near maximum dose (D2%), i.e. RBED2% = D2%,RBE/D2%,phys, where subscripts RBE and phys indicate that the D2% is calculated based on an RBE model and the physical dose, respectively. Compared to the median RBEd of the patient population, differences up to 15% were observed for the individual RBEd values found for the thyroid, while more modest variations were seen for the heart (6%), lungs (2%) and brainstem (<1%). Large inter-patient variation in RBE could be correlated to large spread in LET and dose for these organs at risk (OARs). For OARs with small inter-patient variations, the results show that applying a population based RBE in treatment planning may be a step forward compared to using RBE of 1.1. OARs with large inter-patient RBE variations should ideally be selected for patient-specific biological or RBE robustness analysis if the physical doses are close to known dose thresholds.publishedVersio

Musculoskeletal diseases in Marfan syndrome:a nationwide registry study

BACKGROUND: Marfan syndrome is associated with abnormalities in the musculoskeletal system including scoliosis, pectus deformities, protrusio acetabuli, and foot deformities. Over a life span, many patients with Marfan syndrome will need treatment; however, the musculoskeletal morbidity over a life span is not well described. The aim of the present study was to assess the overall burden of musculoskeletal disease in patients with Marfan syndrome. MATERIALS AND METHODS: A registry-based, nationwide epidemiological study of patients with a Ghent II verified Marfan syndrome diagnosis from 1977 to 2014. Each patient was matched on age, and sex with up to 100 controls from the background population. RESULTS: We identified 407 patients with Marfan syndrome and 40,700 controls and compared their musculoskeletal diagnoses and surgical treatments using Cox proportional hazards ratio (HR). The risk of a registration of a musculoskeletal diagnosis in patients with Marfan syndrome was significantly increased compared to controls (HR: 1.94 (1.69–2.24). One out of six with Marfan syndrome was registered with scoliosis (HR: 36.7 (27.5–48.9). Scoliosis was more common in women with Marfan syndrome compared to men (HR: 4.30 (1.73–1.08)). One out of 11 were registered with a pectus deformity HR: 40.8 (28.1–59.3), and one out of six with a deformity of the foot. Primarily pes planus (HR: 26.0 (15.2–44.3). The proportion of patients with Marfan syndrome (94/407) that underwent musculoskeletal surgery was also significantly higher (HR: 1.76 (1.43–2.16)). The major areas of surgery were the spine, pectups correction, and surgery of the foot/ankle. Ten patients with Marfan syndrome had elective orthopedic surgery without being recognized and diagnosed with Marfan syndrome until later in life. None of these had scoliosis, pectus deformity or a foot deformity. Among patients with an aortic dissection, the age at dissection was 34.3 years in those with at least one major musculoskeletal abnormality. In patients without a major abnormality the age at dissection was 45.1 years (p < 0.01). CONCLUSIONS: The extent of musculoskeletal disease is quite significant in Marfan syndrome, and many will need corrective surgery during their life span. Surgeons should be aware of undiagnosed patients with Marfan syndrome when treating patients with a Marfan syndrome like-phenotype

Hepatitis C treatment uptake among people who inject drugs in Oslo, Norway: A registry-based study

Background Improving HCV treatment uptake among people who inject drugs (PWID) is crucial to achieving the WHO elimination targets. The aims were to evaluate HCV treatment uptake and HCV RNA prevalence in a large cohort of PWID in Norway. Methods Registry-based observational study where all users of the City of Oslo's low-threshold social and health services for PWID between 2010–2016 ( n = 5330) were linked to HCV notifications (1990–2019) and dispensions of HCV treatment, opioid agonist treatment (OAT) and benzodiazepines (2004–2019). Cases were weighted to account for spontaneous HCV clearance. Treatment rates were calculated using person-time of observation, and factors associated with treatment uptake were analysed using logistic regression. HCV RNA prevalence was estimated among individuals alive by the end of 2019. Results Among 2436 participants with chronic HCV infection (mean age 46.8 years, 30.7% female, 73.3% OAT), 1118 (45.9%) had received HCV treatment between 2010–2019 (88.7% DAA-based). Treatment rates increased from 1.4/100 PY (95% CI 1.1–1.8) in the pre-DAA period (2010–2013) to 3.5/100 PY (95% CI 3.0–4.0) in the early DAA period (2014–2016; fibrosis restrictions) and 18.4/100 PY (95% CI 17.2–19.7) in the late DAA period (2017–2019; no restrictions). Treatment rates for 2018 and 2019 exceeded a previously modelled elimination threshold of 50/1000 PWID. Treatment uptake was less likely among women (aOR 0.74; 95% CI 0.62–0.89) and those aged 40–49 years (aOR 0.74; 95% CI 0.56–0.97), and more likely among participants with current OAT (aOR 1.21; 95% CI 1.01–1.45). The estimated HCV RNA prevalence by the end of 2019 was 23.6% (95% CI 22.3–24.9). Conclusion Although HCV treatment uptake among PWID increased, strategies to improve treatment among women and individuals not engaged in OAT should be addressed.This research received funding from the following sources. KM receives research grants from the South-Eastern Norway Regional Health Authority , grant number: 2020011 . The funding sponsor has not been involved in study design, collection of data, analysis/interpretation of data, in the writing of the article, or in the decision to submit the article for publication.publishedVersio