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This article, published in the journal Endoscopy, presents a comparative study that benchmarks the performance of three different Computer-Aided Detection software (CADe) systems for colon polyp detection. The study found that all CADe systems had high sensitivity for polyp detection, ranging from 90% to 100%. However, there was a significant difference in the false positive rates (FPR) per frame, with some systems having a higher FPR than others. The study concludes that while CADe software performs better than endoscopists, there are significant differences between the CADe systems, with the most sensitive software also having the highest FPR. [Extracted from the article]

Background/objectives: The Oslo diet and antismoking study showed that counselling for a healthy lifestyle reduced lifelong coronary mortality in high-risk men. We explored whether the same counselling reduced also cancer risk.Methods: The study randomly allocated males at high coronary risk to either a 5-year intervention for lifestyle changes (cholesterol-lowering dietary changes, weight loss and stopping smoking) or a control group (1 : 1) in 1972/73. We explored the incidence and mortality of all cancers and cancer forms related to smoking, BMI or diet up to 43 years after randomization.Results: A total of 595 men in the intervention and 621 in the control group were included. At inclusion median age was 45 years, 588 (48.4%) subjects were overweight (BMI > 25 kg m-2 ) and 925 (76.1%) current smokers. The intervention did not reduce the risk of cancer after 43 years (adjusted hazard ratio (HR) 0.96, 95% confidence interval (CI) 0.80-1.15). In the first 25 years of follow-up, among the 1088 (89.5%) men who were overweight/obese and/or smokers, the intervention reduced the incidence of those cancer forms related to smoking, BMI or diet (including carcinoma of the respiratory, digestive and urinary tracts; adjusted HR 0.69; 95% CI 0.49-0.99). The intervention had no significant effect on incidence beyond 25 years, or on mortality.Conclusions: The 5-year counselling for a healthy lifestyle did not reduce the overall cancer risk in the very long term. However, in the first 25 years, the counselling reduced the risk of relevant cancer types in overweight/obese subjects and smokers. [ABSTRACT FROM AUTHOR]

Abstract: Aims: The aims of the study were to investigate benefits and challenges in implementing a digital examination and study the clinical relevance of the digital examination in relation to clinical training and practice. Material and method: The study was based on semi‐structured focus‐group interviews from two distinct student populations (2016 and 2017) in a bachelor programme in dental hygiene. In addition, conversational data from a plenary discussion from the whole second student population (2017) were collected and analysed. The data were approached on basis of content analysis. Results: A benefit experienced in the digital examination was the ease in typing and editing answers on the computer. This suggests an increased effectiveness in computer‐based compared to analogue examinations. An additional advantage was the experienced relevance of the examination related to the clinic. This finding refers not only to the digital presentations of images, but also to the entire setting in the clinic and dental practice. The limitations reported by the students were non‐optimal viewing conditions for presenting radiographic images and difficulties in obtaining an overview of the assignments compared to paper‐based examinations due to the linear digital examination format. The last finding on lacking overview revealed an influence on student performances which should be taken seriously in designing digital examinations. Conclusion: In conclusion, the digital layout increases efficiency and clinical relevance of examinations to a certain extent. Obstacles were found in limitations related to image presentation and lack of overview of the examination. The latter challenge raises questions related to developing suitable assessment software. [ABSTRACT FROM AUTHOR]

Background: An important number of patients with suspected cardiac chest pain have non-obstructive coronary artery disease. Our purpose was to describe the clinical characteristics of patients with normal or near-normal coronary arteries in routine cardiological practice in a secondary care hospital. Methods: In 2013, consecutive patients referred for invasive coronary angiography with suspected cardiac chest pain were analysed at a single-centre (Westfriesgasthuis, Hoorn, the Netherlands). Coronary arteries were defined as normal or near-normal if they showed no stenosis or only slight wall irregularities on visual assessment. Patients with a final non-cardiac diagnosis for the chest pain were excluded. Results: A total of 558 patients were included. Of these, 151 (27%) showed normal or near-normal coronary arteries on visual assessment. This group of patients were significantly more often female ( p < 0.001), younger ( p < 0.001) and non-diabetic (p = 0.002). Forty percent of hospitalised patients who had normal or near-normal coronary arteries at coronary angiography showed an elevated troponin. Conclusion: In routine cardiological practice, around 1 out of 4 patients with suspected cardiac chest pain undergoing invasive angiography had normal or near-normal coronary arteries. We suggest that premenopausal women with suspected cardiac chest pain could be considered for non-invasive coronary imaging as a first step in clinical practice. [ABSTRACT FROM AUTHOR]

Net community production (NCP) and carbon to nutrient uptake ratios were studied during a large-scale mesocosm experiment on ocean acidification in Kongsfjorden, western Svalbard, during June--July 2010. Nutrient depleted fjord water with natural plankton assemblages, enclosed in nine mesocosms of ~50m³ in volume, was exposed to pCO2 levels ranging initially from 185 to 1420 μatm. NCP estimations are the cumulative change in dissolved inorganic carbon concentrations after accounting for gas exchange and total alkalinity variations. Stoichiometric coupling between inorganic carbon and nutrient net uptake is shown as a ratio of NCP to a cumulative change in inorganic nutrients. Phytoplankton growth was stimulated by nutrient addition half way through the experiment and three distinct peaks in chlorophyll a concentration were observed during the experiment. Accordingly, the experiment was divided in three phases. Cumulative NCP was similar in all mesocosms over the duration of the experiment. However, in phases I and II, NCP was higher and in phase III lower at elevated pCO2. Due to relatively low inorganic nutrient concentration in phase I, C :N and C : P uptake ratios were calculated only for the period after nutrient addition (phase II and phase III). For the total post-nutrient period (phase II+phase III) ratios were close to Redfield, however they were lower in of NCP, C :N and C : P uptake ratios in different phases reflects the effect of increasing CO2 on phytoplankton community composition and succession. The phytoplankton community was composed predominantly of haptophytes in phase I, prasinophytes, dinoflagellates, and cryptophytes in phase II, and haptophytes, prasinophytes, dinoflagellates and chlorophytes in phase III (Schulz et al., 2013). Increasing ambient inorganic carbon concentrations have also been shown to promote primary production and carbon assimilation. For this study, it is clear that the pelagic ecosystem response to increasing CO2 is more complex than that represented in previous work, e.g. Bellerby et al. (2008). Carbon and nutrient uptake representation in models should, where possible, be more focused on individual plankton functional types as applying a single stoichiometry to a biogeochemical model with regard to the effect of increasing pCO2 may not always be optimal. The phase variability in NCP and stoichiometry may be better understood if CO2 sensitivities of the plankton's functional type biogeochemical uptake kinetics and trophic interactions are better constrained. [ABSTRACT FROM AUTHOR]

A major, potential stressor of marine systems is the changing water chemistry following increasing seawater carbon dioxide concentration (CO2), commonly termed ocean acidification. In order to understand how an Arctic pelagic ecosystem may respond to future CO2, a deliberate ocean acidification and nutrient perturbation study was undertaken in an Arctic fjord. The initial setting and evolution of seawater carbonate chemistry were investigated. Additions of carbon dioxide resulted in a wide range of ocean acidification scenarios. This study documents the changes to the CO2 system throughout the study following net biological consumption and gas exchange with the atmosphere. In light of the common practice of extrapolating results to cover regions away from experimental conditions, a modelling study was also performed to assess the representativeness, in the context of the simulated present and future carbonate system, of the experimental study region to both the near and wider Arctic region. The mesocosm experiment represented the range of simulated marine carbonate system for the coming century and beyond (pCO2 to 1420 µatm) and thus extrapolations may be appropriate to ecosystems exhibiting similar levels of CO2 system drivers. However, as the regional ocean acidification was very heterogenous and did not follow changes in atmospheric CO2, care should be taken in extrapolating the mesocosm response to other regions based on atmospheric CO2 scenarios. [ABSTRACT FROM AUTHOR]

Net community production (NCP) and ratios of carbon to nutrient consumption were studied during a large-scale mesocosm experiment on ocean acidification in Kongsfjorden, West Spitsbergen, during June-July 2010. Nutrient-deplete fjord water with natural phyto- and bacteriaplankton assemblages, enclosed in nine mesocosms of ∼50m³ volume, was exposed to pCO2 levels ranging from 185 to 1420 µatm on initial state. Mean values of pCO2 levels during experiment ranged from 175 to 1085 µatm in different mesocosms. Phytoplankton growth was stimulated by nutrient addition. In this study NCP is estimated as a cumulative change in dissolved inorganic carbon concentrations. Stoichiometric couping between inorganic carbon and nutrient is shown as a ratio of a cumulative NCP to a cumulative change in inorganic nutrients. Three peaks of chlorophyll a concentration occurred during the experiment. Accordingly the experiment was divided in three phases. Overall cumulative NCP was similar in all mesocosms by the final day of experiment. However, NCP varied among phases, showing variable response to CO2 perturbation. Carbon to nitrogen (C:N) and carbon to phosphorus (C: P) uptake ratios were estimated only for the period after nutrient addition (post-nutrient period). For the total post-nutrient period ratios were close to Redfield proportions, however varied from it in different phases. The response of C:N and C: P uptake ratios to CO2 perturbation was different for three phases of the experiment, reflecting variable NCP and dependence on changing microbial community. Through the variable NCP, C:N and C: P uptake ratios for 31 days of the experiment we show a flexibility of biogeochemical response establishing a strong microbial loop in Kongsfjorden under different CO2 scenarios. [ABSTRACT FROM AUTHOR]

Background and study aims: Awithdrawal time of at least 6min has been recommended as a quality indicator for colonoscopy. One drawback of many of the studies that have investigated withdrawal time and produced conflicting results has been their single-center design involving few endoscopists. Therefore, the validity of withdrawal time as a quality measure remains unclear. This study explores the value of individual withdrawal time in a nationwide analysis. Patients and methods: This prospective cohort study comprised data from outpatient colonoscopies performed at 19 Norwegian centers from January to September 2009 and registered in the Norwegian Gastronet Quality Assurance (QA) program. The participating endoscopists were characterized by their median withdrawal time for visual colonoscopies (diagnostic colonoscopies without biopsy or therapy) and categorized into two visual withdrawal time (VWT) groups (<6min or ≥6min) to analyze the predictive value of VWT for detection of one or more polyps ≥5 mmin diameter using multiple logistic regression models. Results: The study included 4429 consecutive colonoscopies performed by 67 endoscopists. The adjusted odds ratio for the detection of polyps ≥5mm was 1.21 (95 %CI 0.94-1.56, P= 0.14) for endoscopists with a median VWT ≥6 min compared with endoscopists with a median VWT <6min. Conclusion: Withdrawal time using 6min as the threshold is not a strong predictor of the likelihood of finding a polyp during colonoscopy and should not be used as a quality indicator. [ABSTRACT FROM AUTHOR]

Background: Colonoscopy requires insufflation of gas for visualization of the bowel wall. Worldwide, this is usually done using air. The aim of the present study was to assess the risk of postcolonoscopy incontinence, and to investigate whether insufflation of CO2 instead of air may reduce this risk, since it is easily absorbed through the bowel mucosa. Methods: This is a prospective multicenter study of colonoscopy patients undergoing bowel insufflation using air or CO2. A successive series of colonoscopies were reported to a national quality assurance program in Norway between January and December 2009 from 21 endoscopy centers with varying insufflation practices. The study comprised 7812 patients aged 18 years or older who were referred for outpatient colonoscopy. Of these, 5015 underwent colonoscopy performed using air and 2797 colonoscopy using CO2 insufflation. Results: Patient-reported incontinence up to 24h after colonoscopy was compared using binary logistic regression analysis for the type of gas used for insufflation. The air and CO2 patient groups were comparable with regard to age, sex, indication for colonoscopy, and sedation practice. Incontinence was reported by 336 out of 7812 patients (4.3 %). Incontinence was significantly less frequent in the CO2 group than in the air group [2.1% versus 5.5 %; adjusted odds ratio (OR) 0.38; 95%CI 0.28-0.50; P<0.001]. Female patients had a higher risk of incontinence than men (adjusted OR 1.77; 95% CI 1.39-2.24; P<0.001). Conclusion: About every 20th patient undergoing colonoscopy using standard air insufflation experiences postexamination incontinence. This proportion can be reduced by 60% by converting from air insufflation to insufflation with the absorbable CO2. [ABSTRACT FROM AUTHOR]

Background and study aims: A withdrawal time of at least 6min has been recommended as a quality indicator for colonoscopy. One drawback of many of the studies that have investigated withdrawal time and produced conflicting results has been their single-center design involving few endoscopists. Therefore, the validity of withdrawal time as a quality measure remains unclear. This study explores the value of individual withdrawal time in a nationwide analysis. Patients and methods: This prospective cohort study comprised data from outpatient colonoscopies performed at 19 Norwegian centers from January to September 2009 and registered in the Norwegian Gastronet Quality Assurance (QA) program. The participating endoscopists were characterized by their median withdrawal time for visual colonoscopies (diagnostic colonoscopies without biopsy or therapy) and categorized into two visual withdrawal time (VWT) groups (<6min or ≥6min) to analyze the predictive value of VWT for detection of one or more polyps ≥5 mmin diameter using multiple logistic regression models. Results: The study included 4429 consecutive colonoscopies performed by 67 endoscopists. The adjusted odds ratio for the detection of polyps ≥5mm was 1.21 (95 %CI 0.94-1.56, P= 0.14) for endoscopists with a median VWT ≥6 min compared with endoscopists with a median VWT <6min. Conclusion: Withdrawal time using 6min as the threshold is not a strong predictor of the likelihood of finding a polyp during colonoscopy and should not be used as a quality indicator. [ABSTRACT FROM AUTHOR]

An energy audit was conducted on a soda ash plant in Botswana, and it was found that the performance of the plant could be improved. Further investigation revealed that the performance of the carbon dioxide (CO2) production section was heavily influenced by control problems experienced at the two coal-firing boilers. The CO2 production section consumes energy in the form of steam and electricity and utilizes a solvent mono-ethanol-amine (MEA) to extract CO2 from boiler flue gasses. Recommendations were made to repair and re-commission the boiler control system and to install an energy optimization system. Annual savings that could be achieved by optimal control of steam from the boilers to the turbine, CO2. plant, and processing plant (thereby controlling the interactions between these sections) amounted to BWP 2, 6 million. This constitutes 10% of the total annual coal bill. A total project life cycle of only 5 years was used, and the escalating savings due to inflation was disregarded. The IRR of the project was calculated to be 114%. This article covers the results of the energy audit. It also discusses the proposed solution and the savings potential that was identified regarding the CO2 plant. [ABSTRACT FROM AUTHOR]