Cation exchange capacity, and amendment effect of gypsum and organic matter on chemical properties of and aggregate stability of bauxite residue

Bauksittavfall (BR) er overskotsprodukt frå ekstrahering av alumina frå bauksittmalm. Bak kvart tonn alumina produserast det 1-2 tonn bauksittavfall, og verdas største aluminaraffineri er Hydro Alunorte, som ligg ved byen Belém, i nordaustlege Brasil. Bauksittavfall er svært alkalisk (pH 11-13), salint og sodisk, og det inneheld høge verdiar av jern, aluminium og sporelement. Målet med denne oppgåva var å undersøke kunnskapshol rundt korleis betre BR som eit medium for plantevekst, då økosystem-restaurering er føreslått som den beste løysinga for å forbetre bauksittavfallsdeponi. Denne oppgåva fokuserte på tre spesifikke utfordringar: 1. Vurdering av kationbyttekapasitet (CEC) i BR, gjennom samanlikning av ein mykje brukt metode kor ammoniumacetat (NH4OAc) ekstraherer kation i BR, og ein metode som belagar seg på at kaliumklorid (KCl) bytar ut adsorbert ammonium (NH4+) etterfølgt av NH4OAc-tilsettinga. 2. Forbetringseffekt på plantevekst i eit kolonneforsøk. Bauksittavfall blei tilsett gips og lokalt organisk materiale: Avfallsproduktet frå Açai -produksjon og matavfall. Vatn blei tilført kolonnene i ei utlekkingserie for å redusere pH, elektrisk leiingsevne og saltinnhald, før tilsetning av raigrasfrø (Lolium perenne). Deretter følgde eit vekstforsøk over fem veker. 3. Aggregatstabilitet av BR med dei ulike jordbetringsmidla, i laboratoriekolonner og i feltprøver frå Hydro Alunorte. Kationbyttekapasiteten blei frå NH4OAc-ekstrahering blei bestemt til om lag 250 meq/100g, medan den var om lag 35 meq/100g med den KCl-utbyttbare metoden. Sistnemnde vart betrakta som den beste representasjonen av den sanne CEC, medan NH4OAc overestimerte den. Utlekkingsforsøket førte EC <4 dS/m og pH blei redusert til 11.9 med 10% gips og 7.5 med 10% gips + 5% matavfall. 10% gips var også mest effektiv i å redusere saltinnhald, med ein SAR = 6.1, og gras viste best vekst i denne behandlinga. Frå feltprøvene førte gips også til signifikant forbetra aggregatstabilitet samanlikna med ubehandla BR, og det var inga signifikant forskjell mellom 5, 10 og 15% gips. Gips med Açai gav litt betre stabilitet enn når berre gips var tilsett. Basert på funna i denne masteroppgåva og tilgjengelegheita av Açai i denne regionen av Brasil, kan gips + Açai vere ein lovande kombinasjon, spesielt dersom avfall frå Açai blei behandla i forkant av tilsetning, for å auke tilgjengelegheita av karbon for mikroorganismar, som ville ført til ein rikare jordfauna og større pH-senking. Açai+ gips bør derfor bli ytterlegerare utforska, i tillegg til langtidsverknaden i felt.Bauxite residue (BR) is the waste product in alumina extraction from bauxite. Behind every tonne alumina, 1-2 tonnes BR is generated, and the world’s largest alumina refinery is Hydro Alunorte, Brazil. Bauxite residue is highly alkaline (pH 11-13), saline and sodic, and it contains high amounts of iron and aluminium and trace elements. The aim of this thesis was to investigate knowledge gaps around how to improve BR as a plant-growth medium, as ecosystem restoration has been pointed out to be the most promising strategy for remediating BR disposal areas. The thesis focused on three specific challenges: 1. Assessment of cation exchange capacity (CEC) in BR, by comparing the common method; ammonium acetate (NH4OAc) extractable cations and another method which includes a second step where potassium chloride (KCl) replaces adsorbed ammonium (NH4+) from the NH4OAc. 2. Amendment effect on plant performance in a column study. Here, BR was amended with 0, 5, and 10 % gypsum and 0 and 5% locally derived organic matter: Waste from Açai berry production and food waste. Water was added to the columns in a leachate series to reduce pH, electrical conductivity, and sodicity, before seeds of rye grass (Lolium perenne) were planted. The growth was observed for five weeks. 3. Aggregate stability on amended and unamended BR with both samples from the columns and field-samples from Hydro Alunorte. The determined CEC by NH4OAc extraction was about 250 meq/100g, while it was about 35 meq/100g by the KCl exchangeable method. The latter was considered to better represent the true CEC in BR, while NH4OAc highly overestimated it. The leaching experiment resulted in a reduction of the EC<4 dS/m and a pH of 8.9 with 10% gypsum and 7.5 with 10% gypsum and 5% food waste. 10% gypsum was also most effective in reducing sodicity, and grass performed best in this treatment, followed by 10% gypsum and 5% Açai waste. Gypsum application resulted in significantly improved aggregate stability compared to unamended BR, and it was no significant difference between 5%, 10% or 15% gypsum added. Gypsum with Açai waste resulted in slightly better stability then when only gypsum was applied. Based on the findings in this study and the availability of Açai in this region of Brazil, Gypsum + Açai waste could be a promising amendment, especially if the Açai waste was composted to a certain degree before augmenting, to provide more easily available carbon and nutrient sources, which could lead to richer soil fauna and greater pH-reducing effect. The effect of Açai + gypsum should therefore be further investigated, as well as its long-term effect in the field.Norsk Hydro ASAM-MIN

Possible opioid-saving effect of cannabis-based medicine using individual-based data from the Norwegian Prescription Database

Some ecological studies have shown that areas with higher use of cannabis may have lower opioid use and fewer opioid-related problems. Newer studies are questioning this finding. Few individually based studies have been performed. Using data from the Norwegian Prescription Database, this study investigated the individual level effect of prescribed cannabis extract (Sativex®) in prescription opioid users on their opioid use in the following year. Looking at all those filling a prescription for Sativex®, opioid use was only marginally lowered in the follow-up period. Some Sativex® users, however, filled more prescriptions for Sativex® and were able to reduce their opioid use substantially. Further studies are needed to elucidate more details on these patients, so as to know who can benefit from such cannabis-based extracts in reducing their opioid use

Quality of life among patients undergoing bariatric surgery: associations with mental health- A 1 year follow-up study of bariatric surgery patients

Background: Preoperative mental health seems to have useful predictive value for Health Related Quality of Life (HRQOL) after bariatric surgery. The aim of the present study was to assess pre- and postoperative psychiatric disorders and their associations with pre- and postoperative HRQOL. Method: Data were assessed before (n = 127) and one year after surgery (n = 87). Psychiatric disorders were assessed by Mini International Neuropsychiatric Interview (M.I.N.I.) and Structured Clinical Interview (SCID-II). HRQOL was assessed by the Short Form 36 (SF-36) questionnaire. Results: Significant improvements were found in HRQOL from preoperative assessment to follow-up one year after surgery. For the total study population, the degree of improvement was statistically significant (p values < .001) for seven of the eight SF-36 subscales from preoperative assessment to follow-up one year after surgery. Patients without psychiatric disorders had no impairments in postoperative HRQOL, and patients with psychiatric disorders that resolved after surgery had small impairments on two of the eight SF-36 subscales compared to the population norm (all effect sizes < .5) at follow-up one year after surgery. Patients with psychiatric disorders that persisted after surgery had impaired HRQOL at follow-up one year after surgery compared to the population norm, with effect sizes for the differences from moderate to large (all effect sizes ≥ .6). Conclusion: This study reports the novel finding that patients without postoperative psychiatric disorders achieved a HRQOL comparable to the general population one year after bariatric surgery; while patients with postoperative psychiatric disorders did not reach the HRQOL level of the general population. Our results support monitoring patients with psychiatric disorders persisting after surgery for suboptimal improvements in quality of life after bariatric surgery

Bruk av SCOFF for diagnostisering av spiseforstyrrelser i allmennpraksis

Den initiale presentasjonen av spiseforstyrrelser i allmennpraksis er ofte kryptisk med diffuse fysiske og psykiske symptomer og derfor vanskelig å diagnostisere. Britiske studier har vist at under halvparten av klinisk presenterte spiseforstyrrelser identifiseres. Vi har liten grunn til å tro at det er vesentlig forskjellig i Norge. Det er en alminnelig oppfatning i litteraturen og blant spesialister på området at tidlig diagnostisering har en klar positiv effekt på pasientens prognose. Målet med oppgaven har vært å finne frem til et godt dokumentert tiltak som vil kunne bedre diagnostiseringen av spiseforstyrrelser i en norsk allmennpraksis. Etter en gjennomgang av temaet ved litteratursøk i Cochrane og Pubmed, samt samtaler med norske allmennleger og speisalister på fagfeltet, kom vi frem til at SCOFF bør brukes som et screeningverktøy ved mistanke om en spiseforstyrrelse. En SCOFF-anamnese er rask og enkel å gjennomføre og har høy negativ prediktiv verdi. Positiv SCOFF-anamnese må føre til videre utredning. KONKLUSJON: Vi ser SCOFF som et enkelt, godt tilgjengelig, billig og trygt verktøy for bruk i norsk allmennpraksis. Det egner seg godt til å utelukke en mistenkt spiseforstyrrelse, og kan gi et kraftig insitament for videre utredning

A 4-Day Mindfulness-Based Cognitive Behavioral Intervention Program for CFS/ME. An Open Study, With 1-Year Follow-Up

Background: Chronic Fatigue Syndrome/Myalgic Encephalopathy (CFS/ME) is an incapacitating illness in which single treatment interventions seem to have variable effects. Based on an earlier study we have conducted a new study with a concentrated intervention program. The aims of this study were to: (1) explore the clinical course for patients with CFS/ME who participated in a treatment program delivered during four consecutive days, and (2) evaluate their satisfaction with this program.Methods: 305 patients diagnosed with CFS/ME (Oxford criteria), recruited from a clinical population referred to a specialist outpatient clinic, participated in an open uncontrolled study of the clinical course through 1 year. The study group participated in a 4-day group intervention program, comprised by education, cognitive group therapy sessions, mindfulness sessions, physical activity and writing sessions, within a context of cognitive behavioral therapy, mindfulness, acceptance and commitment model.Assessments were done by self-reports prior to the first consultation, 1 week before and 1 week after the intervention program, and at 3 months and 1 year after the intervention. SPSS 23 and R 3.3 were used for statistical analyses. The associations between case definitions and the outcome measures (Chalder Fatigue Scale (FS), Short Form 36 (SF-36) physical functioning scale) were assessed by a linear mixed effects model (LME).Results: Results showed statistically significant clinical changes for 80% of the patients after the intervention, changes being sustained through 1 year after the program. For both Fatigue Scale (FS) and the SF-36 there were statistically significant effects of time from baseline to all time points with a statistically significant drop in scores, applying the linear mixed effects model.A subgroup fulfilling the inclusion criteria from the PACE study (Chalder Fatigue Scale &gt;6/11, SF-36 Physical functioning &lt;65/100) showed clinically significant improvement through 1 year, changes in outcome measures were statistically significant (p &lt; 0.001). None of the patients included in the program dropped out, and a great majority of patients expressed high satisfaction with the content, focus and amount of treatment. Conclusion: Clinical changes observed from pre-treatment to 1 year follow-up could represent effects of the 4-day concentrated intervention program, and should be further explored in a controlled study

Fatty acid metabolism in Atlantic salmon (Salmo salar L.) hepatocytes and influence of dietary vegetable oil

Isolated hepatocytes from Atlantic salmon (Salmo salar), fed diets containing either 100% fish oil or a vegetable oil blend replacing 75% of the fish oil, were incubated with a range of seven 14C-labelled fatty acids. The fatty acids were; [1-14C]16:0, [1-14C]18:1n-9, [1-14C]18:2n-6, [1-14C]18:3n-3, [1-14C]20:4n-6, [1-14C]20:5n-3, and [1-14C]22:6n-3. After 2 hours of incubation the hepatocytes and medium were analyzed for acid soluble products, incorporation into lipid classes, and hepatocytes for desaturation and elongation. Uptake into hepatocytes was highest with [1-14C]18:2n-6 and [1-14C]20:5n-3 and lowest with [1-14C]16:0. The highest recovery of radioactivity in the cells was found in triacylglycerols. Of the phospholipids the highest recovery was found in phosphatidylcholine, with [1-14C]16:0 and [1-14C]22:6n-3 being the most prominent fatty acids. The rates of β-oxidation were as follows: 20:4n-6 > 18:2n-6 = 16:0 > 18:1n-9 > 22:6n-3 = 18:3n-3 = 20:5n-3. Of the fatty acids taken up by the hepatocytes, [1-14C]16:0 and [1-14C]18:1n-9 were subsequently exported the most, with the majority of radioactivity recovered in phospholipids and triacylglycerols, respectively. The major products from desaturation and elongation were generally one cycle of elongation of the fatty acids. Diet had a clear effect on the overall lipid metabolism, with replacing 75% of the fish oil with vegetable oil resulting in decreased uptake of all fatty acids and reduced incorporation of fatty acids into cellular lipids, but increased β-oxidation activity, and higher recovery in products of desaturation and elongation of [1-14C]18:2n-6 and [1-14C]18:3n-3

Increasing the dietary n-6/n-3 ratio alters the hepatic eicosanoid production after acute stress in Atlantic salmon (Salmo salar)

Earlier studies have indicated that a high inclusion of n-6 fatty acids (FA) in feeds for Atlantic salmon can affect the stress response. To test this hypothesis, Atlantic salmon (Salmo salar) were fed diets containing varying dietary n-6/n-3 FA ratios and different absolute levels of n-6 and n-3 FAs. The fish were divided into two different stress challenge groups, where one group was exposed to three weekly hypoxia challenges for 4 weeks (repeated stress), while one group was left undisturbed. At the end of the experiment, both groups were exposed to an acute stressor (lowering of water level). Thus, effects of the diets on acute stress, repeated stress and the combined effect of these could be investigated. In general, there were few effects of the repeated stress, while fish in all diet groups responded strongly to the acute stress based on several stress markers. Dietary n-6/n-3 ratio did not affect growth, all fish appeared phenotypically healthy, and all groups were able to mount an acute stress response. However, there was an interaction between diet and repeated stress on cortisol response after acute stress, possibly indicating altered hypothalamic-pituitary adrenal axis reactivity in fish fed high n-6/n-3 FA ratio. Hepatic levels of prostaglandin D2 (PGD2) and leukotriene B4 responded differently to acute stress depending on the dietary n-6/n3 FA ratio, indicating an altered acute stress response. Additionally, increasing the dietary n-6/n-3 FA content led to higher levels of PGD2 and PGE2 as well as higher liver triacylglycerol. In summary, the results suggest that increasing the dietary n-6/n-3 FA ratio in salmon feeds can affect the way they respond to stressors in an aquaculture setting, possibly affecting the fish robustness.publishedVersio

Antimicrobial susceptibility testing of Bacteroides species by disk diffusion: The NordicAST Bacteroides study

Objectives - Antimicrobial susceptibility testing (AST) of anaerobic bacteria has until recently been done by MIC methods. We have carried out a multi-centre evaluation of the newly validated EUCAST disk diffusion method for AST of Bacteroides spp. Methods - A panel of 30 Bacteroides strains was assembled based on reference agar dilution MICs, resistance gene detection and quantification of cfiA carbapenemase gene expression. Nordic clinical microbiology laboratories (n = 45) performed disk diffusion on Fastidious Anaerobe Agar with 5% mechanically defibrinated horse blood (FAA-HB) for piperacillin-tazobactam, meropenem and metronidazole. Results - A total of 43/45 (95.6%) laboratories carried out disk diffusion per protocol. Intraclass correlation coefficients were 0.87 (0.80–0.93) for piperacillin-tazobactam, 0.95 (0.91–0.97) for meropenem and 0.89 (0.83–0.94) for metronidazole. For metronidazole, one media lot yielded smaller zones and higher variability than another. Piperacillin-tazobactam and meropenem zone diameters correlated negatively with cfiA expression. A meropenem zone diameter of Conclusions - Inter-laboratory agreement by disk diffusion was good or very good. The main challenges were media-related variability for metronidazole and categorical disagreement with the reference method for piperacillin-tazobactam in some cfiA-positive strains. An area of technical uncertainty specific for such strains may be warranted

Periodontitis is associated with decreased experimental pressure pain tolerance: The Tromsø Study 2015–2016

Aim - To assess the relationship between periodontitis and experimental pain tolerance. Materials and Methods - Participants from the population-based seventh survey of the Tromsø Study with data on periodontitis were included (n = 3666, 40–84 years old, 51.6% women). Pain tolerance was assessed through (i) pressure pain tolerance (PPT) test with a computerized cuff pressure algometry on the leg, and (ii) cold-pressor tolerance (CPT) test where one hand was placed in circulating 3°C water. Cox proportional hazard regression was used to assess the association between periodontitis and pain tolerance adjusted for age, sex, education, smoking and obesity. Results - In the fully adjusted model using the 2012 Centers for Disease Control/American Academy of Periodntology case definitions for surveillance of periodontitis, moderate (hazard ratio [HR] = 1.09; 95% confidence interval [CI]: 1.01, 1.18) and severe (HR = 1.25, 95% CI: 1.11, 1.42) periodontitis were associated with decreased PPT. Using the 2018 classification of periodontitis, having Stage II/III/IV periodontitis was significantly associated with decreased PPT (HR = 1.09; 95% CI: 1.01, 1.18) compared with having no or stage I periodontitis. There were no significant associations between periodontitis and CPT in fully adjusted models. Conclusions - Moderate and severe periodontitis was associated with experimental PPT

Pain tolerance after stroke: The Tromsø study

Background: Stroke lesions might alter pain processing and modulation by affecting the widely distributed network of brain regions involved. We aimed to compare pain tolerance in stroke survivors and stroke-free persons in the general population, with and without chronic pain. Methods: We included all participants of the sixth and seventh wave of the population-based Tromsø Study who had been tested with the cold pressor test (hand in cold water bath, 3°C, maximum time 106 s in the sixth wave and 120 s in the seventh) and who had information on previous stroke status and covariates. Data on stroke status were obtained from the Tromsø Study Cardiovascular Disease Register and the Norwegian Stroke Register. Cox regression models were fitted using stroke prior to study attendance as the independent variable, cold pressor endurance time as time variable and hand withdrawal from cold water as event. Statistical adjustments were made for age, sex, diabetes, hypertension, hyperlipidaemia, body mass index and smoking. Results: In total 21,837 participants were included, 311 of them with previous stroke. Stroke was associated with decreased cold pain tolerance time, with 28% increased hazard of hand withdrawal (hazard ratio [HR] 1.28, 95% CI 1.10–1.50). The effect was similar in participants with (HR 1.28, 95% CI 0.99–1.66) and without chronic pain (HR 1.29, 95% CI 1.04–1.59). Conclusions: Stroke survivors, with and without chronic pain, had lower cold pressor pain tolerance, with possible clinical implications for pain in this group. Significance: We found lower pain tolerance in participants with previous stroke compared to stroke-free participants of a large, population-based study. The association was present both in those with and without chronic pain. The results may warrant increased awareness by health professionals towards pain experienced by stroke patients in response to injuries, diseases and procedures