Estimation of net apparent erosion in the SW Barents Sea by applying velocity inversion analysis

The SW Barents Sea was subjected to significant uplift and erosion during the Cenozoic, processes that are believed to have had a significant impact on hydrocarbon maturation and migration in the area. The current study uses compaction of shale- and sand-dominated layers to make a map of net apparent erosion throughout the SW Barents Sea. The map shows regional trends consistent with deep-seated isostatic uplift of the crust in combination with glacial erosion as a driving mechanism for the erosion.We find increased erosion towards the north and decreased erosion towards the west, in the western Barents Sea. The trend of highest erosion has an axis stretching in a SE–NW orientation towards Svalbard. This indicates a major change in the crustal uplift pattern in the transition from the Norwegian mainland to the Barents Sea. The velocity inversion method used in this study combined with a two-baseline normal compaction trend model demonstrates a reliable procedure for accurate erosion estimations. It allows erosion estimates from layers with different lithologies to be integrated into a common interpretation and differences to be interpreted geologically: for example, an apparent facies change to a mixed sand–shale lithology, possibly with reservoir quality sands developed, in the Cretaceous on the Bjarmeland Platform

Subtypes of insomnia and the risk of chronic spinal pain: the HUNT study

Objective: To examine the association between subtypes of insomnia and the risk of chronic spinal pain. Methods:The study comprised 16,401 participants without chronic spinal pain at baseline who were followed for ~11 years. People were categorized into ‘no insomnia symptoms’,‘subthreshold insomnia’,and ‘insomnia’. Insomnia was defined according to the diagnostic classification system requiring both daytime and nighttime symptoms, and further categorized into subtypes based on nighttime symptoms(ie, sleep onset latency [SOL-insomnia], wake after sleep onset [WASO-insomnia], early morning awakening [EMA-insomnia], or combinations of these). Subthreshold insomnia comprised those with only daytime impairment or one or more nighttime symptoms. Chronic spinal pain was defined as pain in either ‘neck’, ‘low back’, or ‘upper back’, or a combination of these. Results: In multivariable regression analysis using people without insomnia as reference, people with subthreshold insomnia or insomnia had relative risks (RRs) of chronic spinal pain of 1.29 (95% confidence interval [CI] 1.21e1.38) and 1.50 (95% CI 1.34e1.68), respectively. The RRs for people with one nighttime symptom were 1.30 (95% CI 0.83e2.05) for WASO-insomnia, 1.32 (95% CI 1.06e1.65) for EMA-insomnia, and 1.70 (95% CI 1.32e2.18) for SOL-insomnia, respectively. Combinations of nighttime insomnia symptoms gave RRs from 1.45 (95% CI 1.08e1.94) for WASOþEMA-insomnia to 1.72 (95% CI 1.36e2.19)for all nighttime symptoms (SOLþWASOþEMA-insomnia). Conclusions: These findings suggest that the risk of chronic spinal pain is highest among persons with insomnia subtypes characterized by sleep onset latency or among those having insomnia symptoms in allparts of the sleep period

Quantification of the magnitude of net erosion in the southwest Barents Sea using sonic velocities and compaction trends in shales and sandstones

During specific intervals within Mesozoic and Cenozoic times, several areas of the southwestern Barents Sea were subjected to uplift and erosion. Areas with missing shallow stratigraphic interval sections and major erosion can be seen at several places along interpreted regional profiles in the southwestern Barents Sea. A new Normal Compaction Trend (NCT) for two selected shale– and sandstone–dominated lithologies has been constructed based on sonic logs in the southwestern Barents Sea. The shale– dominated NCT is calibrated to the Cretaceous shales in the Northern North Sea and Norwegian Sea and applied to the Cretaceous shales of the Barents Sea. The sandstone–dominated NCT is calibrated to the Lower Jurassic Åre Formation of the Norwegian Sea and applied to the Lower Jurassic–Upper Triassic coastal plain section in the Barents Sea. By utilising the NCT model, the study estimates net apparent erosion in 28 selected Barents Sea wells based on comparison of sonic log velocities. A net apparent erosion map of the study area was constructed by gridding of the well values. The accuracy of the map is limited in areas with little well control, such as in the northwest, where the east–west transition into the southwestern Barents Sea region is poorly constrained. With that in mind, the map clearly shows two regional trends which dominate the erosion pattern in the study area; an increasing amount of erosion towards the north and a sharp decrease of erosion westwards of the hinge zone into the southwestern Barents Sea. The highest erosion estimates are observed towards Svalbard, with values up to 2500 m. The results of this study can be further utilized in petroleum system studies in the eroded areas

Prognostic ability of STarT Back Screening Tool combined with work-related factors in patients with low back pain in primary care: a prospective study

Objective Primary care screening tools for patients with low back pain may improve outcome by identifying modifiable obstacles for recovery. The STarT Back Screening Tool (SBST) consists of nine biological and psychological items, with less focus on work-related factors. We aimed at testing the prognostic ability of SBST and the effect of adding items for future and present work ability. Methods Prospective observational study in patients (n=158) attending primary care physical therapy for low back pain. The prognostic ability of SBST and the added prognostic value of two work items; expectation for future work ability and current work ability, were calculated for disability, pain and quality of life outcome at 3 months follow-up. The medium and high-risk group in the SBST were collapsed in the analyses due to few patients in the high-risk group. The prognostic ability was assessed using the explained variance (R2) of the outcomes from univariable and multivariable linear regression and beta values with 95% CIs were used to assess the prognostic value of individual items. Results The SBST classified 107 (67.7%) patients as low risk and 51 (32.3%) patients as medium/high risk. SBST provided prognostic ability for disability (R2=0.35), pain (R2=0.25) and quality of life (R2=0.28). Expectation for return to work predicted outcome in univariable analyses but provided limited additional prognostic ability when added to the SBST. Present work ability provided additional prognostic ability for disability (β=−2.5; 95% CI=−3.6 to −1.4), pain (β=−0.2; 95% CI=−0.5 to −0.002) and quality of life (β=0.02; 95% CI=0.001 to 0.04) in the multivariable analyses. The explained variance (R2) when work ability was added to the SBST was 0.60, 0.49 and 0.47 for disability, pain and quality of life, respectively. Conclusions Adding one work ability item to the SBST gives additional prognostic information across core outcomes

Genetic variants related to physical activity or sedentary behaviour: a systematic review

Background Research shows that part of the variation in physical activity and sedentary behaviour may be explained by genetic factors. Identifying genetic variants associated with physical activity and sedentary behaviour can improve causal inference in physical activity research. The aim of this systematic review was to provide an updated overview of the evidence of genetic variants associated with physical activity or sedentary behaviour. Methods We performed systematic literature searches in PubMed and Embase for studies published from 1990 to April 2020 using keywords relating to “physical activity”, “exercise”, “sedentariness” and “genetics”. Physical activity phenotypes were either based on self-report (e.g., questionnaires, diaries) or objective measures (e.g., accelerometry, pedometer). We considered original studies aiming to i) identify new genetic variants associated with physical activity or sedentary behaviour (i.e., genome wide association studies [GWAS]), or ii) assess the association between known genetic variants and physical activity or sedentary behaviour (i.e., candidate gene studies). Study selection, data extraction, and critical appraisal were carried out by independent researchers, and risk of bias and methodological quality was assessed for all included studies. Results Fifty-four out of 5420 identified records met the inclusion criteria. Six of the included studies were GWAS, whereas 48 used a candidate gene approach. Only one GWAS and three candidate gene studies were considered high-quality. The six GWAS discovered up to 10 single nucleotide polymorphisms (SNPs) associated with physical activity or sedentariness that reached genome-wide significance. In total, the candidate gene studies reported 30 different genes that were associated (p < 0.05) with physical activity or sedentary behaviour. SNPs in or close to nine candidate genes were associated with physical activity or sedentary behaviour in more than one study. Conclusion GWAS have reported up to 10 loci associated with physical activity or sedentary behaviour. Candidate gene studies have pointed to some interesting genetic variants, but few have been replicated. Our review highlights the need for high-quality GWAS in large population-based samples, and with objectively assessed phenotypes, in order to establish robust genetic instruments for physical activity and sedentary behaviour. Furthermore, consistent replications in GWAS are needed to improve credibility of genetic variants