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Introduction: The management to reduce risk of thromboembolic complications in polycythemia vera and essential thrombocythemia are well established, but for other conditions with elevated hemoglobin, hematocrit, or platelets there are no consensus regarding treatment and follow up. Aims: To assess frequency of elevated blood values in patients with thromboembolic event, how many of these should be investigated further regarding myeloproliferative neoplasm and if the risk of recurrent event is depending on underlying condition. Methods: Retrospective cohort study of 3931 adult patients in the county of Norrbotten, Sweden, with thromboembolism during 2017 and 2018. Results: Of the 3931 patients, 1195 had either elevated Hb, HCT, or platelets fulfilling the 2016 revised WHO criteria for PV and ET, and out of these 411 should be evaluated regarding underlying myeloproliferative neoplasms. Unexplained thrombocytosis and secondary erythrocytosis were associated with the highest rate of recurrent event as well as the most inferior restricted mean survival time. Conclusion: Elevated blood values are common in patients with thromboembolic event and the high risk of recurrent event and inferior restricted mean survival time in patients with unexplained thrombocytosis and secondary erythrocytosis implicates the importance of finding and managing the underlying condition.

Background The use of direct oral anticoagulants (DOAC) in patients with non-valvular atrial fibrillation (NVAF) and advanced chronic kidney disease (CKD) including dialysis is growing. Several studies have shown favorable results of DOAC compared with warfarin regarding bleeding risk but no difference in stroke protection. However, these studies had poor time in therapeutic range (TTR), in the warfarin comparison group. Methods This was a Swedish national cohort study investigating the risk of ischemic stroke and major bleeding on DOAC compared with warfarin in patients with NVAF, glomerular filtration rate category 3–5D (G3–G5D), kidney transplant recipients excluded, between 2009 and 2018. Data extracted from high-quality national healthcare registries including the Swedish Renal Registry, AuriculA (the Swedish national quality register for AF and anticoagulation) and The Stroke Register. Results At enrolment, of 2453 patients 59% were treated with warfarin (mean TTR 67%) and 41% with DOAC. Overall, 693 (28.3%) had G3, 1113 (45.4%) G4, 222 (9.1%) G5 and 425 (17.3%) G5D. DOAC compared with warfarin showed lower hazard of major bleeding [hazard ratio 0.71 (95% confidence interval 0.53–0.96)] but no difference in ischemic stroke risk. Mortality was increased during DOAC treatment [1.24 (1.01–1.53)], presumably not a causal association since fewer fatal bleedings occurred on DOAC. Conclusions DOAC treatment, compared with warfarin, is associated with almost 30% lower risk of bleeding in patients with NVAF and CKD G3–G5D. The stroke risk is comparable between the treatments. This is the first study comparing DOAC and well-managed warfarin (TTR 67%) in advanced CKD. Ongoing and planned randomized controlled trials need to confirm the possible benefit of DOAC.

Funding Information: The authors appreciatively acknowledge the funding of the Academy of Finland, grant number 315020 and 353299. Publisher Copyright: © 2023 The Author(s) A large part of the refining heat production in the thermomechanical pulp mill can be recovered to supply the paper machine heat demand. This study introduces a novel approach for the heat integration of a thermomechanical pulp mill and paper machine using Energy Hub. An Energy Hub consisting of a steam generator heat pump and the electric boiler is integrated with the thermomechanical pulp mill to provide the heating demand of the paper machine. The advanced cost-efficient design and operation of the Energy Hub are investigated in this research by integrating thermo-economic analysis, reliability & availability assessment, and load profile prediction. The thermo-economic analysis combines economics and thermodynamics, which is necessary for energy system unit commitments. Reliability assessment will lead to more accurate modeling of real-life system operating conditions since system components' availability is considered in the design process. Load profile prediction estimates the Energy Hub load for the next hour, which helps with the optimal operation of the Energy Hub. Different state-of-the-art long-short-term memory (LSTM) neural network models have been developed to achieve the best time series model for refining heat prediction in the thermomechanical pulp mill. Results show that all the time series models are effective for refining heat prediction, while Bidirectional LSTM appears to perform better than others with the correlation coefficient and root mean square error of 0.9 and 0.15, respectively. In addition, the proposed Energy Hub design approach is compared with the conventional design method. The proposed design method offers a robust design that isn't impacted by unsupplied demand penalty rates. Depending on the penalty rates, the total system cost could decrease by 14%-28% utilizing the proposed design method.

Background This study examined the effects of regulated and controlled supramaximal high-intensity interval training (HIT) adapted for older adults, compared to moderate-intensity training (MIT), on cardiorespiratory fitness; cognitive, cardiovascular, and muscular function; and quality of life. Methods Sixty-eight nonexercising older adults (66–79 years, 44% males) were randomized to 3 months of twice-weekly HIT (20-minute session including 10 × 6-second intervals) or MIT (40-minute session including 3 × 8-minute intervals) on stationary bicycles in an ordinary gym setting. Individualized target intensity was watt controlled with a standardized pedaling cadence and individual adjustment of the resistance load. Primary outcomes were cardiorespiratory fitness (V̇o2peak) and global cognitive function (unit-weighted composite). Results V̇o2peak increased significantly (mean 1.38 mL/kg/min, 95% CI [0.77, 1.98]), with no between-group difference (mean difference 0.05 [−1.17, 1.25]). Global cognition did not improve (0.02 [−0.05, 0.09]), nor differed between groups (0.11 [−0.03, 0.24]). Significant between-group differences in change were observed for working memory (0.32 [0.01, 0.64]), and maximal isometric knee extensor muscle strength (0.07 N·m/kg [0.003, 0.137]), both in favor of HIT. Irrespective of the group, there was a negative change in episodic memory (−0.15 [−0.28, −0.02]), a positive change in visuospatial ability (0.26 [0.08, 0.44]), and a decrease in systolic (−2.09 mmHg [−3.54, −0.64]) and diastolic (−1.27 mmHg [−2.31, −0.25]) blood pressure. Conclusions In nonexercising older adults, 3 months of watt-controlled supramaximal HIT improved cardiorespiratory fitness and cardiovascular function to a similar extent as MIT, despite half the training time. In favor of HIT, there was an improvement in muscular function and a potential domain-specific effect on working memory. Clinical Trial Registration NCT03765385

Background Observational data comparing warfarin with no treatment for patients with non-valvular atrial fibrillation (NVAF) and severely reduced glomerular filtration rate (GFR) are conflicting and randomized controlled trials (RCTs) are lacking. Most studies do not provide information on warfarin treatment quality, making them difficult to compare. Methods This national cohort study investigates the risk of ischaemic stroke and major bleeding during warfarin treatment compared with no oral anticoagulants in patients with NVAF, GFR category 3–5 (G3–G5) or on dialysis (G5D), with kidney transplant recipients excluded, between 2009 and 2018. Data extracted from high-quality Swedish national healthcare registries, including the Swedish Renal Registry, AuriculA—the Swedish national quality registry for atrial fibrillation and anticoagulation—and the Stroke Registry. Results At enrolment of 12 106 patients, 21.4% were G3, 43.5% were G4, 11.6% were G5 and 23.6% were G5D. The mean time in the therapeutic range was 70%. Warfarin compared with no treatment showed a lower risk for ischaemic stroke for G3 {hazard ratio [HR] 0.37 [95% confidence interval (CI) 0.18–0.76]}, G4 [0.53 (0.38–0.74)] and G5D [0.49 (0.30–0.79)] and an increased risk of major bleeding in G4 [HR 1.22 (1.02–1.46)], G5 [1.52 (1.15–2.01)] and G5D [1.23 (1.00–1.51)]. All-cause mortality was more than halved on warfarin compared with no treatment in all GFR categories. Conclusions Warfarin treatment is associated with a lower risk of ischaemic stroke for patients with NVAF and G3, G4 and G5D at the cost of a higher risk of major bleeding for G4–G5D. Existing observational data are conflicting, stressing the need for RCTs on warfarin compared with no treatment in G4–G5D. Awaiting RCTs, it seems reasonable to treat selected patients on dialysis and NVAF with warfarin.

The aim of this study was to evaluate chronic pain 1 year after surgery, and risk factors for chronic pain after groin hernia repair in women.Groin hernia surgery in women is less frequently studied than in men. Chronic pain is common after groin hernia surgery and remains an important area with room for improvement. Previous studies are small or inconclusive. Guidelines recommend timely repair of all female groin hernias.From the Swedish Hernia Register 4021 female and 37,542 male patients operated between September 1, 2012 and August 30, 2017 responded to a patient-reported outcome questionnaire (response rate 70.0%) 1 year after primary groin hernia surgery. Multivariable analysis was performed to compare chronic postoperative pain in women with men as a control group, and to evaluate risk factors for chronic pain in women.Among women operated for groin hernia, 18% suffered chronic postoperative pain. The risk for chronic pain was significantly higher for women [odds ratio 1.3 (95% confidence interval 1.16-1.46). Three risk factors for chronic pain in women were found: high body mass index, high American Society of Anesthesiologists classification, and femoral hernia. No differences in chronic pain in women were seen when comparing surgical methods or emergency versus elective surgery.Almost one-fifth of women suffered of chronic pain affecting daily activity after groin hernia repair. Chronic pain was more common for women than men. In view of the high-rate chronic postoperative pain, further research on management strategies in female groin hernia is warranted.

BACKGROUND AND AIMS Warfarin has traditionally been the drug of choice for patients with atrial fibrillation and GFR METHOD A Swedish retrospective national cohort study investigating the risk of ischemic stroke and major bleeding in patients with non-valvular atrial fibrillation (NVAF) during warfarin treatment depending on iTTR (individual time in therapeutic range). Patients included have warfarin treated NVAF, eGFR RESULTS At enrolment of 2421 patients (29.1% female) 22.1% had G3 (eGFR 59–30 mL/min/1.73 m2) 47.4% G4 (eGFR 15–29), 10.9% G5 (eGFR 70% compared with CONCLUSION Warfarin treatment quality worsens with decreasing GFR. Higher iTTR confers a lower risk of major bleeding and death for patients with NVAF and CKD, eGFR

Aims Visual information about subclinical atherosclerosis was provided to physicians and participants in the VIPVIZA trial, inclusion 2013–16 in northern Sweden, aiming to improve adherence to cardiovascular disease (CVD) prevention guidelines. Pictorial risk information may be more actionable. The aim of this study was to investigate the effect of intervention with pictorial risk information on time to first dispensing of statins. Methods and results Asymptomatic atherosclerotic disease was screened for by carotid ultrasound examination in 3532 participants enrolled in VIPVIZA, of those 3000 met the criteria for this study. Participants were randomly assigned to receive pictorial risk information consisting of graphical representation of atherosclerosis as compared to a control group without intervention. Time to initiation of statins was assessed during 5 years of follow-up through the National prescribed drug register. After 3 years, both groups were re-examined and received the intervention information. In the intervention group, initiation of statins increased considerably for the first 3 years and a smaller increase was also seen after re-intervention. After the cross-over, the control group showed a sharp increase in initiation of statins, almost reaching the same proportion treated at 5 years. The propensity to initiate statin treatment increased over the study period and there was no difference between men and women. Conclusions The pictorial information had an effect on time to initiation of statins, both as original and repeated intervention and also in the control group after single-arm cross-over. The current study supports pictorial information as a tool to shorten time to initiation of statins for CVD prevention. The VIPVIZA study is registered with ClinicalTrials.gov, number NCT01849575.

Background and Objectives Exercise can be an important way of maintaining balance function in people with dementia, but further investigation is needed to determine the optimal way of exercising. The objective was to evaluate whether exercise applicability (i.e., attendance, exercise intensity, and adverse events) and motivation were associated with the effect on functional balance of a high-intensity functional exercise program for older people with dementia in nursing homes. Design, Setting and Participants Exercise intervention participants (n = 81; 60 women, 21 men) from a randomized controlled trial (UMDEX) were included. Their mean age was 84 and mean Mini-Mental State Examination score was 15. Intervention Groups of 3–8 participants participated in the High-Intensity Functional Exercise (HIFE) Program, with 5 sessions per 2-week period, for 4 months (total, 40 sessions). Measurements Outcome was the Berg Balance Scale (BBS), assessed at baseline and follow up, and the score difference, dichotomized to classify participants into two groups: responders (≥5-point increase) and non-responders ( Results The BBS score was 28.6 ± 14.3 at baseline and 31.2 ± 15.3 at follow up, with the difference between follow-up and baseline scores ranging from −35 to 24. Twenty-nine (35.8%) participants were responders. The multivariable models showed no significant association between responders vs. non-responders and any target variable. Conclusion Participation in a 4-month high-intensity functional exercise program can improve balance in many individuals with dementia in nursing homes, despite the progressiveness of dementia disorders and several co-existing medical conditions. Predicting balance exercise response based on applicability and motivation seem not to be possible, which lends no support for excluding this group from functional exercise, even when exercise intensity or motivation is not high.

A refining model is developed to analyses the refining process’s energy efficiency based on the refining variables. A simulation model is obtained for longer-term refining energy analysis by further developing the MATLAB Thermo-Mechanical Pulping Simulink toolbox. This model is utilized to predict two essential variables for refining energy efficiency calculation: refining motor-load and generated steam. The conventional variable for presenting refining energy efficiency is refining specific energy consumption (RSEC), which is the ratio of the refining motor load to throughput and does not consider the share of recovered energy from the refining produced steam. In this study, a new variable, corrected refining specific energy consumption (CRSEC), is introduced and practiced for better representation of the refining energy efficiency. In the calculation process of the CRSEC, recovered energy from the refining generated steam is considered useful energy. The developed model results in 160% and 78.75% improvement in simulation model determination coefficient and error, respectively. Utilizing the developed model and hourly district heating demand for CRSEC calculation, results prove a 22% annual average difference between CRSEC and RSEC. Findings confirm that the wintertime refining energy efficiency is 27% higher due to higher recovered energy in the heat recovery unit compared to summertime.

Background and aims A high body mass index (BMI) is considered a risk factor for ventral abdominal wall hernias but protective for the development of groin hernias. The reason for this is unclear. The surrounding abdominal fat in obesity might “protect” and limit the passage through the inguinal canal. The aim was to compare two different methods used for obesity registration in groin hernia patients and to investigate the hypothesis of high BMI/low groin hernia risk phenomenon. Methods This was a population-based observational study comparing BMI to waist circumference (WC) as well as their correlations to the quantity of groin hernia repair performed in either sex. Two national registers were crosslinked to a large regional register including information on WC. Results A larger WC and a higher BMI were associated with a lower risk of having groin hernia repair in both sexes. There was no difference using either WC or BMI as a risk factor for groin hernia repair in either sex. There was no advantage to using body composition based on WC rather than BMI for surgery indication. Conclusions Overweight patients, both men and women, have a lower risk of undergoing groin hernia repair regardless of fat distribution. BMI is a well-established method for obesity registration and is recommended in the evaluation of hernia patients.

Soot sludge is a waste stream formed in the fuel oil gasification of formic acid and hydrogen peroxide production. The soot sludge has a high moisture content (95%) and is presently combusted with heavy fuel oil in order to dispose of the sludge. Experimental tests earlier conducted by the authors have shown that the sludge can be convectively dried with sawdust in a fixed bed. By upgrading the sludge from waste to fuel, the utilization of oil can be decreased. In this study, characteristic drying curves (CDC) are determined for the sludge and sawdust mixture. The CDCs are further used to evaluate the economy of the mixture drying in a belt dryer by using the payback period method. Results show that the linear CDCs of the mixture can be used to extrapolate drying data from specific drying conditions to another when the bed height is 200 or 300 mm, and the inlet air temperature 40&ndash, 100 &deg, C. The economic analysis shows that drying is economical for all inlet air temperatures if the oil price is &ge, 350 &euro, /t-oil. Sensitivity analyses reveal that the heat, sawdust and emission prices have no remarkable influence on the economy of drying if the oil price does not fall below c. 300 &euro, /t-oil.

BackgroundThe effectiveness of different procedures in routine surgical practice for hernia repair with respect to chronic postoperative pain and reoperation rates is not clear.MethodsThis was prospective cohort study based on a unique combination of patient-reported outcomes and national registry data. Virtually all patients with a groin hernia repair in Sweden between September 2012 and April 2015 were sent a questionnaire 1 year after surgery. Persistent pain, defined as at least ‘pain present, cannot be ignored, and interferes with concentration on everyday activities’ in the past week was the primary outcome. Reoperation for recurrence recorded in the register was the secondary outcome.ResultsIn total, 22 917 patients (response rate 75·5 per cent) who had an elective unilateral groin hernia repair were analysed. Persistent pain present 1 year after hernia repair was reported by 15·2 per cent of patients. The risk was least for endoscopic total extraperitoneal (TEP) repair (adjusted odds ratio (OR) 0·84, 95 per cent c.i. 0·74 to 0·96), compared with open anterior mesh repair. TEP repair had an increased risk of reoperation for recurrence (adjusted OR 2·14, 1·52 to 2·98), as did open preperitoneal mesh repair (adjusted OR 2·34, 1·42 to 3·71) at 2·5-year follow-up. No other methods of repair differed significantly from open anterior mesh repair.ConclusionThe risk of significant pain 1 year after groin hernia repair in routine surgical practice was 15·2 per cent. This figure was lower in patients who had surgery by an endoscopic technique, but at the price of a significantly higher risk of reoperation for recurrence.

Background: Although physical exercise has been suggested to influence cognitive function, previous exercise studies show inconsistent results in people with dementia. Objectives: To investigate effects of exercise on cognitive function in people with dementia. Method: The Umea a Dementia and Exercise (UMDEX) study, a cluster-randomized controlled trial, was set in 16 nursing homes in Umea, Sweden. One hundred-and-forty-one women and 45 men with dementia; mean age of 85 y and mean MiniMental State Examination (MMSE) score of 15, were randomized to a High-Intensity Functional Exercise program or a seated attention control activity. Blinded assessors measured global cognitive function using the MMSE and the Alzheimer's disease Assessment Scale -Cognitive subscale (ADAS-Cog), and executive function using Verbal fluency (VF) at baseline and 4 months (directly after intervention completion), and MMSE and VF at 7 months. Results: Linear mixed models showed no between-group effects in mean difference from baseline (95% confidence intervals, CI) at 4 months in MMSE (-0.27; 95% CI -1.4 to 0.87, p = 0.644), ADAS-Cog (-1.04, 95% CI -4 to 1.92, p = 0.491), or VF (-0.53, 95% CI -1.42 to 0.35, p = 0.241) or at 7 months in MMSE (-1.15, 95% CI -2.32 to 0.03, p = 0.056) or VF (-0.18, 95% CI -1.09 to 0.74, p = 0.707). Conclusion: A 4-month, high-intensity functional exercise program had no superior effects on global cognition or executive function in people with dementia living in nursing homes when compared with an attention control activity. Originally published in manuscript form with title [Effects of exercise on cognitive function in older people with dementia: a randomized controlled study]

In recirculating aquaculture, a bacterial biofilter is applied to convert ammonium, excreted by the fish, to the non-toxic nitrate. Unfortunately, nitrifying bacteria produce off-flavor compounds that lower fish quality. We investigated, by calculations and estimations, possibilities to replace the biofilter by autotrophic organisms that incorporate ammonium in biomass, consume other mineral nutrients and produce marketable biomass and oxygen. The capacity of microalgae, macroalgae, duckweed, strawberry, and tomato to assimilate ammonium was calculated, using data from an existing Finnish fresh water fish farm. Microalgae were found to be the most effective for ammonium removal, and they would be able to consume the ammonium produced by a fish farm if the algae were grown in a facility with approximately twice the area of the fish farm itself. Macroalgae and duckweed appeared to be the second best option for ammonium removal, and strawberry and tomato were predicted to have a somewhat smaller capacity for ammonium removal. Due to low ammonium content, microalgae cannot be cultivated in the recirculating water, but rather the nutrients should be allowed to diffuse through a semipermeable membrane to microalgae.

Background Improved recurrence rates after groin hernia surgery have led to chronic pain becoming the most troublesome postoperative complication. Self-gripping mesh was developed to decrease the risk for development of chronic pain. The aim of this nationwide cohort study was to compare recurrence rate and chronic pain 1 year after an open, anterior mesh repair of inguinal hernias with either a self-gripping mesh or other lightweight mesh. Method All operations registered as open anterior mesh repair (Lichtenstein) in the Swedish Hernia Registry between September 2012 and October 2016 were selected. At 1 year after repair, patients were sent a pain questionnaire assessing chronic pain. We compared the prevalence of chronic pain and reoperation for recurrence using lightweight, sutured mesh or self-gripping mesh. Results We analyzed the 1,803 repairs using self-gripping mesh and 16,567 repairs using lightweight mesh. We found no difference in the prevalence of chronic pain 1 year after the hernia repair between self-gripping mesh and sutured lightweight mesh (OR 0.92, CI 95% 0.80–1.06, P = .257). There was no increase in reoperation for recurrence when using self-gripping mesh (HR 0.71, CI 95% 0.45–1.14, P = .156). Mean operation time was considerably less when using self-gripping mesh (43 vs 70 minutes; P > .001). Conclusion The use of self-gripping mesh does not decrease the incidence of chronic pain and reoperation for recurrence compared with lightweight, sutured mesh for open anterior mesh repair of inguinal hernias. Furthermore, the use of self-gripping mesh is associated with a clinically important, lesser operation time.

In this article, we show how a revised district heat network control strategy can be employed to utilize the storage capabilities of the network. An optimization problem is formulated, with minimum operating costs as the objective. Allowing the district heat supply temperature to vary freely within given boundaries results in approximately 2% reduction in annual heat provision costs, in comparison to a reference control scheme in a case study. The benefits of added heat storage functionality in the network are greatest when there is a large difference between district heat generation costs from the available heat sources. In general, supply temperature optimization results in increased operational hours of those plants, whose variable costs are the lowest. (C) 2019 Elsevier Ltd. All rights reserved.

Energy system design is complex and the long utilization time of plants and the variance in economic parameters induce uncertainty into the outcome. In this article, different design objectives in a mid-sized district heating system design are evaluated. A mixed integer linear multi-objective optimization model is formulated and solved for maximum profit, minimum exergy losses, minimum CO2 emissions, minimum district heat primary energy factor and minimum district heat primary exergy (PeXa) factor. Energy system design should include metrics that take externalities into account. A combination of profit, CO2 and primary energy factor is recognized as a feasible set of design objectives. Exergy losses do not represent sustainability viewpoint well in energy system design - PeXa method expands it to fit system evaluation better. Optimization models such as this may provide relevant information for system operators, and for setting policy actions. (C) 2018 Elsevier Ltd. All rights reserved.

This paper presents a performance study of deep borehole heat exchangers. The coaxial borehole heat exchanger (BHE) has been selected because for the present conditions it has a better performance ...

In this paper a simplified and not fully discretized numerical model is used to simulate the performance of a non-grouted (water filled) borehole heat exchanger (BHE). The model enables simulation ...

OBJECTIVES: To investigate the effects of a high-intensity functional exercise program on independence in activities of daily living (ADLs) and balance in older people with dementia and whether exercise effects differed between dementia types. DESIGN: Cluster-randomized controlled trial: Umeå Dementia and Exercise (UMDEX) study. SETTING: Residential care facilities, Umeå, Sweden. PARTICIPANTS: Individuals aged 65 and older with a dementia diagnosis, a Mini-Mental State Examination score of 10 or greater, and dependence in ADLs (N = 186). INTERVENTION: Ninety-three participants each were allocated to the high-intensity functional exercise program, comprising lower limb strength and balance exercises, and 93 to a seated control activity. MEASUREMENTS: Blinded assessors measured ADL independence using the Functional Independence Measure (FIM) and Barthel Index (BI) and balance using the Berg Balance Scale (BBS) at baseline and 4 (directly after intervention completion) and 7 months. RESULTS: Linear mixed models showed no between-group effect on ADL independence at 4 (FIM=1.3, 95% confidence interval (CI)=-1.6-4.3; BI=0.6, 95% CI=-0.2-1.4) or 7 (FIM=0.8, 95% CI=-2.2-3.8; BI=0.6, 95% CI=-0.3-1.4) months. A significant between-group effect on balance favoring exercise was observed at 4 months (BBS=4.2, 95% CI=1.8-6.6). In interaction analyses, exercise effects differed significantly between dementia types. Positive between-group exercise effects were found in participants with non-Alzheimer's dementia according to the FIM at 7 months and BI and BBS at 4 and 7 months. CONCLUSION: In older people with mild to moderate dementia living in residential care facilities, a 4-month high-intensity functional exercise program appears to slow decline in ADL independence and improve balance, albeit only in participants with non-Alzheimer's dementia.

doi: 10.1080/07373937.2018.1492615 Drying woody biomass holds the potential to improve the energy efficiency of certain processes, such as in CHP plants. Drying can also be a necessary unit process in several energy conversion processes (e.g. in biomass gasification). Belt dryers are typically used for drying when low temperature air (100–110 °C) is used. This article aims to produce new knowledge about the influence of the main design parameters on the drying costs of a low temperature belt dryer when three different materials (forest residue, bark, as well as sawdust and soot sludge mixture) are dried using it. The influence is analyzed by changing the following parameters: bed height, air temperature, air velocity and initial/final moisture contents of the material. The study aims to evaluate which of these parameters has an actual effect on drying costs. Results indicate that the lowest costs are achieved with the highest air temperature if the heat price is the same for every air temperature level. However, an optimal bed height depends on the material. Increasing the air velocity does not necessarily decrease the costs. In the sensitivity analysis, to factor in the influence of the temperature on the heat price, the price was changed for every drying air temperature (1, 5, 10 and 15 €/MWh). This analysis showed that the lowest drying costs are achieved by the lowest air temperature in all cases, thus indicating that the price of the heat has a remarkable influence on the economics of drying. Furthermore, the results support the use of low temperature heat sources in drying if they are clearly less expensive than higher temperature heat sources. However, if the prices for lower and higher air temperatures are of the same magnitude, the higher air temperatures are preferable. In general, this paper shows that it is important to pay attention to the main design parameters to optimize total drying costs. For example, if an overly low bed height is used in woodchips or bark drying, the total drying costs might be dozens of per cent higher than inthe most economic case.

This study examines the energy and mass balances of algae cultivation and different post-processing pathways. Flue gases and excess heat from a combined heat and power (CHP) plant are used in algae cultivation, with nutrients from municipal wastewater. In the studied pathways, algae are cultivated in open ponds and photobioreactors with or without artificial lighting. Algal mass is used for methane, biodiesel or ethanol production, or it is combusted in a boiler. Results show that in most process pathways energy output exceeds the energy consumption in processing, and the energy returns are approximately twice as large as the electricity input. A large fraction of input energy is low-temperature heat, while the products have a higher value. Energy outputs from different pathways are similar, but heat and electricity consumption in processing vary significantly. Supercritical water gasification pathway is identified as a possible future option, whereas lipid extraction pathways are suggested to be the most likely candidates for industrial scale operations.

Background: When analyzing data collected with a geographical dimension it is important to be able to test for spatial autocorrelation. The presence of spatial autocorrelation might unveil ignored ...

Soot sludge is formed in the production of formic acid. Currently, this waste is combusted together with heavy fuel oil in a boiler. The current theoretical lower heating value of the sludge is − 23.8 MJ/kg d.b. . Drying of sludge increases the heating value, and decreases oil use. Drying of pure sludge in a fixed bed is impossible in practice and therefore sawdust is mixed with it before drying. This study aims to fill the gap in knowledge about soot sludge and sawdust drying by studying its drying kinetics experimentally in a fixed bed. The influence of drying on fuel oil consumption is also preliminarily evaluated. Drying curves were determined for bed heights of 100, 200 and 300 mm, inlet air temperatures of 40, 80 and 100 °C, and air velocities of 0.75 and 0.9 m/s. According to the results, the optimal mixture ratio of soot sludge and sawdust is 50% soot sludge : 50% sawdust (vol.%), with an air velocity of 0.75 m/s and a bed height of 200 mm. Oil savings of 104 MJ/kg dry, soot sludge are achieved when the mixture is dried to the final moisture content of 40%.

The European Union's goal is to increase the share of renewable energy sources to 20 per cent and that of liquid biofuels for transport to at least 10 per cent by 2020. Liquid biofuels for transport are, for example, biodiesel and bioethanol. Their use is not assumed to increase CO 2 -emissions in the atmosphere. However, production processes of transport fuels need energy causing indirect CO 2 -emissions. To evaluate the environmental burden of these biofuels it is important to consider indirect CO 2 -emissions in analyses, too. This study defines indirect CO 2 -emissions for Digestion process, Bioethanol process, FT-process (Fischer-Tropsch-process) and Bio-SNG-process and compares their environmental burden.

Chronic pain is common after groin hernia surgery, affecting approximately 10% of patients. The type of anesthesia has been shown to affect short term pain (within 30 days) where Local Anesthesia ( ...

Drying of wood chips at a power plant site increases the lower heating value and decreases composting and dry matter losses in long-term storage. In this study, experimentally measured drying curves for wood chips are produced to study the drying kinetics of the chips. Drying curves have been used to assess whether or not wood chip drying in a batch-type fixed bed dryer at a municipal Combined Heat and Power (CHP) plant site is profitable when using external excess heat or solar energy as a heat source in drying, and what could be the reasonable drying parameters for that. The curves have been determined by changing bed heights (100, 300, 500 mm), temperature of inlet air (30, 50, 70, 90°C) and air velocities (0.3 m/s, 0.5 m/s, 0.7 m/s) in the tests. Air has been used as a drying gas. The results show that drying time decreases considerably when the temperature of the drying air increases from 50°C to 70°C. The influence of drying air temperature on the drying time is no longer so remarkable as the temper...

This paper presents a MILP (Mixed Integer Linear Programming) model for a continuous packed-bed biomass dryer. The model minimizes total drying costs, including both capital and operational costs, of the dryer. Heated air, which flows through a biomass bed and perforated conveyor, is used as drying gas by the dryer. We define the dryer size with the help of an experimentally-measured characteristic drying curve. The MILP model is tested in a case study where the dryer is assumed to have been installed at a Scandinavian pulp and paper mill. There are three different heat sources available for the heating of drying air: warm water at 60 °C, warm water at 80 °C and backpressure steam at the pressure of 0.4 MPa. The results indicate that, in practice, the use of only low-temperature warm water flows for heating of drying air is the most economic method when their prices are low (below 1 € MWh-1 in the case study). Warm water flows are usually waste heat from pulp and paper mills and their prices are low compared to the price of back-pressure steam (typically from 10 to 15 € MWh-1). The use of steam for drying may be reasonable if the price of warm water is for some reason clearly higher than the price of a typical waste-heat stream. The MILP model presented in this work can be used for minimizing drying costs of any material (not only biomass) dried in a continuous packed-bed dryer if the characteristic drying curve of the material is available.

The aim of this study was to investigate reoperation for recurrence in men and women with respect to method of repair, hernia anatomy and year of operation.Since 1992, groin hernia repairs performed in Sweden are prospectively registered in the Swedish Hernia Register, (SHR). Reoperations are noted, regardless of where the reoperation is performed. Risk of reoperation for recurrence is calculated for men and women with respect of method of repair, hernia anatomy and year of operation.Out of 221 108 eligible operations registered between 1992-2013, 17 545 (8%) were performed on women. The risk of being operated for recurrence after laparoscopic surgery was lowered in women, RR 0,4(95%CI 0.3-0.7) and increased in men, RR 2.3(95% CI 2.0-2.7), compared to the Lichtenstein technique.The reoperation for recurrence rate differed significantly between men and women. As regards the technique used for primary repair, laparoscopic groin hernia repair lowered the risk of reoperation for recurrence in women whereas it doubled the risk in men.

Purpose The pathogenesis of groin hernia is not fully understood and some suggested risk factors are debatable. This population-based study evaluates the association between groin hernia repair and tobacco use. Method An observational study based on register linkage between the Swedish Hernia Register and the Vasterbotten Intervention Program (VIP). All primary groin hernia repairs performed from 2001 to 2013 in the county of Vasterbotten, Sweden, were included. Results VIP provided data on the use of tobacco in 102,857 individuals. Neither smoking nor the use of snus, increased the risk for requiring a groin hernia repair. On the contrary, heavy smoking decreased the risk for men, HR 0.75 (95% CI 0.58-0.96), as did having a BMI over 30 kg/m 2 HR (men) 0.33 (95% CI 0.27-0.40). Conclusion Tobacco use is not a risk factor for requiring a groin hernia repair, whereas having a low BMI significantly increases the risk.

Purpose Surgical repair of groin hernia should be carried out with minimal complication rates, and it is important to have regular quality control and accurate means of assessment. The Swedish healthcare system has a mutual insurance company (LÖF) that receives claims from patients who have suffered healthcare-related damage or malpractice. The Swedish Hernia Register (SHR) currently covers around 98% of all Swedish groin hernia operations. The aim of this study was to analyse damage claims following groin hernia repair surgery and link these with entries in the SHR, in order to identify risk factors and causes of injuries and malpractice associated with hernia repair. Methods Data on all 48,574 groin hernia operations registered in the SHR between 2008 and 2010 were compared and linked with data on claims made to the Swedish National Patient Injury Insurance (LÖF). Results Of the 130 damage claims received by LÖF, 26 dealt with bleeding, 20 with testicular injury and 7 with intestinal lesions. Eighty (62%) of the complications were considered malpractice according to the Swedish Patient Injury Act. Acute and recurrent surgery, sutured repair and general anaesthesia were associated with a significantly increased risk for a damage claim independently the patients were compensated or not. Females filed claims in greater proportion than males. There was no significant difference in background factors between claims accepted by LÖF and compensated and those who were rejected compensation. Conclusion Risk factors for filing a damage claim included acute surgery, operation for recurrence, sutured repair and general anaesthesia, whereas local anaesthesia reduced the risk.

In a combined heat and power plant (CHP plant), heat and power are produced simultaneously in the same power plant process. The CHP technology reduces total fuel consumption compared to a situation where heat and electricity are produced separately. For condensing power plants the exergy loss is usually calculated by multiplying the entropy generation rate with the real environmental temperature because the plant exchanges heat with the environment at the temperature close to this temperature. Instead, CHP plants emit heat into the environment at higher temperature level. The goal of this paper is to perform the Second Law analysis for a coal-fired CHP plant undergoing Clausius–Rankine cycle. The Second Law analysis is based on the use of effective heat-absorbing and heat-emitting temperatures. In this paper, temperatures are defined for a CHP plant undergoing Clausius–Rankine cycle. The maximum power to heat ratio of the CHP plant as well as entropy generation and power (exergy) losses are defined using the before mentioned temperatures instead of the real environmental temperature.

This paper evaluates the performance of a compressor driven and an absorption heat pump on the basis of exergy analysis using two different approaches. Approach 1 is based on the calculation of the effective heat absorbing and emitting temperatures and the entropy generation rate. Approach 2 is based on the commonly used exergy analysis where the real ambient temperature is used. The main goal is to analyze how these two approaches differ from each other. Approach 1 gives the exact improvement potential (Wreal - Wmin) of the heat pump while Approach 2 underestimates it. The average flow temperature also approximates the correct improvement potential with sufficient accuracy when temperature change of the flow is relatively small. Both approaches can be used when performances of heat pumps are compared. Both approaches also give a more realistic view of the performance than the commonly used COP, especially regarding the absorption heat pump.

In this study biomass-based energy production was introduced to an urban city area of Helsinki, Finland. The study compared two cases in integration with a municipality: (1) biomass fuelled small-scale CHP (combined heat and power)-plant and (2) a biorefinery. The comparison was made according to primary energy consumption, primary energy factors, CO2 (carbon dioxide) emissions and the price of produced biowax. It was also studied how results are influenced by different assumptions. The results showed that the primary energy consumption and CO2 emissions were higher in the biorefinery case in absolute amounts as more products i.e. biowax was produced. The results indicated the primary energy factors were almost the same for both cases. Additionally, the primary energy use was very low for district heat and electricity produced in the biorefinery, when the primary energy use of the biorefinery was allocated only to the biowax. The sensitivity analysis of biowax pricing showed that a biorefinery is a competitive alternative for a CHP-plant if the prices of biomass and market electricity are low and the price of CO2 allowance is high. In terms of overall energy efficiency comparison, the comparison cannot be properly completed, because of the different end-products of the plants.

This paper studies allocation of fuel costs and CO2-emissions to heat and power in a CHP plant producing heat to an integrated pulp and paper mill and electricity to the liberalized electricity markets (or to the mill by the market price). The CHP plant and the mill are considered to be two separate economical units and both the mill and the CHP plant perspectives are discussed. Fuel costs and CO2-emissions are allocated using the energy, exergy and market based methods. The CHP plant purchases black liquor and bark from the mill. It also purchases oil from the markets to cover the whole fuel demand of the plant. The results indicate that the marked based method can be recommended as a “neutral” cost allocation method, because with that, the energy producer is not collecting extra margins from selling steam. This means that heat pricing is cost based. The results also indicate that depending on the emission factor and efficiency of alternative energy production form, the marked based method or the exergy method allocate the lowest CO2-emissions to heat. Therefore, the use of market based method for allocating costs and CO2 emissions can be recommended in order to use one single approach in both.

This paper introduces a new type of contact drying method that has been developed at Aalto University in Finland. The paper also presents experimental results from tests with the new drying method. The drying system consists of a hot upper plate, a cold bottom plate, a vacuum inside the drying chamber and a mechanical press. An experimental drying device was built and used in a study to compare the new method with the currently used drying methods. The study includes drying time experiments and tests on veneer quality. The results were compared to veneers which had been dried in a convective dryer. Compared to conventional convective drying, the new method decreased the total drying time significantly, by approximately 50%. The preliminary tests show that the quality of the veneer was not compromised in the drying process. The new method could be used in the plywood and LVL manufacturing process, as well as in special drying applications. The results showed that the new system was a viable drying ...

The statistical analysis of mixed effects models for binary and count data is investigated. In the statistical computing environment R, there are a few packages that estimate models of this kind. T ...