| 1. |
- Harbo, HF, et al.
(författare)
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Two genome-wide linkage disequilibrium screens in Scandinavian multiple sclerosis patients
- 2003
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Ingår i: Journal of Neuroimmunology. - : Elsevier BV. - 1872-8421 .- 0165-5728. ; 143:1-2, s. 101-106
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Tidskriftsartikel (refereegranskat)abstract
- We report the first two genome-wide screens for linkage disequilibrium between putative multiple sclerosis (MS) susceptibility genes and genetic markers performed in the genetically homogenous Scandinavian population, using 6000 microsatellite markers and DNA pools of approximately 200 MS cases and 200 controls in each screen. Usable data were achieved from the same 3331 markers in both screens. Nine markers from eight genomic regions (1p33, 3q13, 6p21, 6q14, 7p22, 9p21, 9q21 and Xq22) were identified as potentially associated with MS in both screens. (C) 2003 Elsevier B.V. All rights reserved.
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| 7. |
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| 8. |
- Modin, A., et al.
(författare)
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Electronic structure of Cu3N films studied by soft x-ray spectroscopy
- 2008
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Ingår i: Journal of Physics. - : IOP Publishing. - 0953-8984 .- 1361-648X. ; 20:23
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Tidskriftsartikel (refereegranskat)abstract
- Soft x- ray emission spectroscopy was used to characterize the electronic structure of seven copper nitride films, one synthesized with atomic layer deposition ( ALD) and six grown with chemical vapor deposition ( CVD) at different preparation temperatures. Interpretation of the x- ray emission spectra was supported by calculations of the electronic structure for bulk pure Cu3N and Cu3N with: an excess of Cu atoms, oxygen or carbon impurities, and N vacancies. The calculations are shown to describe the experimental spectra quite well. Analysis of the x- ray spectra suggests that films grown in copper rich environments and above a cut- off temperature of approximately 360 degrees C have a growing fraction of copper enriched areas, while films prepared below this temperature do not have these areas with excess copper.
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| 9. |
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| 10. |
- Saheb-Alam, S., et al.
(författare)
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Effect of Start-Up Strategies and Electrode Materials on Carbon Dioxide Reduction on Biocathodes
- 2018
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Ingår i: Applied and Environmental Microbiology. - : American Society for Microbiology. - 0099-2240 .- 1098-5336. ; 84:4
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Tidskriftsartikel (refereegranskat)abstract
- The enrichment of CO2-reducing microbial biocathodes is challenging. Previous research has shown that a promising approach could be to first enrich bio-anodes and then lower the potential so the electrodes are converted into biocathodes. However, the effect of such a transition on the microbial community on the electrode has not been studied. The goal of this study was thus to compare the start-up of biocathodes from preenriched anodes with direct start-up from bare electrodes and to investigate changes in microbial community composition. The effect of three electrode materials on the long-term performance of the biocathodes was also investigated. In this study, preenrichment of acetate-oxidizing bioanodes did not facilitate the start-up of biocathodes. It took about 170 days for the preenriched electrodes to generate substantial cathodic current, compared to 83 days for the bare electrodes. Graphite foil and carbon felt cathodes produced higher current at the beginning of the experiment than did graphite rods. However, all electrodes produced similar current densities at the end of the over 1-year-long study (2.5 A/m(2)). Methane was the only product detected during operation of the biocathodes. Acetate was the only product detected after inhibition of the methanogens. Microbial community analysis showed that Geobacter sp. dominated the bioanodes. On the biocathodes, the Geobacter sp. was succeeded by Methanobacterium spp., which made up more than 80% of the population. After inhibition of the methanogens, Acetobacterium sp. became dominant on the electrodes (40% relative abundance). The results suggested that bioelectrochemically generated H-2 acted as an electron donor for CO2 reduction. IMPORTANCE In microbial electrochemical systems, living microorganisms function as catalysts for reactions on the anode and/or the cathode. There is a variety of potential applications, ranging from wastewater treatment and biogas generation to production of chemicals. Systems with biocathodes could be used to reduce CO2 to methane, acetate, or other high-value chemicals. The technique can be used to convert solar energy to chemicals. However, enriching biocathodes that are capable of CO2 reduction is more difficult and less studied than enriching bioanodes. The effect of different start-up strategies and electrode materials on the microbial communities that are enriched on biocathodes has not been studied. The purpose of this study was to investigate two different start-up strategies and three different electrode materials for start-up and long-term operation of biocathodes capable of reducing CO2 to valuable biochemicals.
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| 11. |
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| 12. |
- Bergström, Malin, et al.
(författare)
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Fifty moves a year: is there an association between joint physical custody and psychosomatic problems in children?
- 2015
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Ingår i: Journal of Epidemiology and Community Health. - : BMJ Publishing Group. - 0143-005X .- 1470-2738. ; 69:8, s. 769-774
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Tidskriftsartikel (refereegranskat)abstract
- Background In many Western countries, an increasing number of children with separated parents have joint physical custody, that is, live equally much in their parents respective homes. In Sweden, joint physical custody is particularly common and concerns between 30% and 40% of the children with separated parents. It has been hypothesised that the frequent moves and lack of stability in parenting may be stressful for these children. Methods We used data from a national classroom survey of all sixth and ninth grade students in Sweden (N=147839) to investigate the association between childrens psychosomatic problems and living arrangements. Children in joint physical custody were compared with those living only or mostly with one parent and in nuclear families. We conducted sex-specific linear regression analyses for z-transformed sum scores of psychosomatic problems and adjusted for age, country of origin as well as childrens satisfaction with material resources and relationships to parents. Clustering by school was accounted for by using a two-level random intercept model. Results Children in joint physical custody suffered from less psychosomatic problems than those living mostly or only with one parent but reported more symptoms than those in nuclear families. Satisfaction with their material resources and parent-child relationships was associated with childrens psychosomatic health but could not explain the differences between children in the different living arrangements. Conclusions Children with non-cohabitant parents experience more psychosomatic problems than those in nuclear families. Those in joint physical custody do however report better psychosomatic health than children living mostly or only with one parent. Longitudinal studies with information on family factors before and after the separation are needed to inform policy of childrens postseparation living arrangements.
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| 13. |
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| 14. |
- Bruckner, Tim .A., et al.
(författare)
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Cold ambient temperature in utero and birth outcomes in Uppsala, Sweden, 1915 to 1929
- 2014
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Ingår i: Annals of Epidemiology. - : Elsevier BV. - 1047-2797 .- 1873-2585. ; 24:2, s. 116-121
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Tidskriftsartikel (refereegranskat)abstract
- PurposeAlthough the literature reports adverse birth outcomes following ambient heat, less work focuses on cold. We, moreover, know of no studies of cold that examine stillbirth. We tested the relation between cold ambient temperature during pregnancy in Sweden and four outcomes: stillbirth, preterm, birth weight for gestational age, and birth length. We examined births from 1915 to 1929 in Uppsala, Sweden, which—unlike most societies today—experienced substandard indoor-heating and fewer amenities to provide shelter from cold.MethodsWe retrieved data on almost 14,000 deliveries from the Uppsala Birth Cohort Study. We linked a validated, daily ambient temperature series to all pregnancies and applied Cox proportional hazards (stillbirth and preterm) and linear regression models (birth weight and length). We tested for nonlinearity using quadratic splines.ResultsThe risk of stillbirth rose as ambient temperature during pregnancy fell (hazard ratio for a 1°C decrease in temperature, 1.08; 95% confidence interval, 1.00 to 1.17). Cold extremes adversely affected preterm and birth length, whereas warm extremes increased preterm risk. We observed no relation between cold and birth weight for gestational age.ConclusionIn historical Sweden, cold temperatures during pregnancy increased stillbirth and preterm risk and reduced birth length among live births.
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| 15. |
- Butorin, Sergei M., et al.
(författare)
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Local Symmetry Effects in Actinide 4f X-ray Absorption in Oxides
- 2016
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Ingår i: Analytical Chemistry. - : American Chemical Society (ACS). - 0003-2700 .- 1520-6882. ; 88:8, s. 4169-4173
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Tidskriftsartikel (refereegranskat)abstract
- A systematic X-ray absorption study at actinide N-6,(7) (4f -> 6d transitions) edges was performed for light-actinide oxides including data obtained for the first time for NpO2, PuO2 and UO3. The measurements were supported by ab initio calculations based on local-density approximation. with added 5f-5f Coulomb interaction (LDA+U). Improved energy resolution compared to common experiments at actinide L-2,L-3 (2p -> 6d transitions) edges allowed us to resolve the major structures of the 13 unoccupied 6d density of states (DOS) and estimate the crystal-field 116) splittings in the 6d shell directly from the spectra of light-actinide dioxides. The measurements demonstrated an enhanced sensitivity of the N-6,N-7, spectral shape to changes in the compound crystal structure. For nonstoichiometric NpO2-x, the filling of the entire band gap with Np 6d states was observed thus supporting a phase coexistence of Np metal and stoichiometric NpO2 which is in agreement with the tentative Np-O phase diagram.
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| 16. |
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| 17. |
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| 18. |
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| 19. |
- Hjern, Anders, et al.
(författare)
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Migrant density and well-being-A national school survey of 15-year-olds in Sweden
- 2013
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Ingår i: European Journal of Public Health. - : Oxford University Press (OUP): Policy B - Oxford Open Option D. - 1101-1262 .- 1464-360X. ; 23:5, s. 823-828
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Tidskriftsartikel (refereegranskat)abstract
- Background: The aim of this study was to investigate the impact of migrant density in school on the well-being of pupils with a migrant origin in first as well as second generation. Methods: Cross-sectional analysis of data from a national classroom survey of 15-year-old Swedish schoolchildren. The study population included 76 229 pupils (86.5% participation) with complete data set from 1352 schools. Six dimensions of well-being from the KIDSCREEN were analysed in two-level linear regression models to assess the influence of migrant origin at individual level and percentage of students with a migrant origin at school level, as well as interaction terms between them. Z-scores were used to equalize scales. Results: A high density (andgt; 50%) of pupils with a migrant origin in first or second generation was associated with positive well-being on all six scales for foreign-born pupils originating in Africa or Asia compared with schools with low (andlt; 10%) migrant density. The effect sizes were 0.56 for boys and 0.29 for girls on the comprehensive KIDSCREEN 10-index (P andlt; 0.001) and 0.61 and 0.34, respectively, for psychological well-being (P andlt; 0.001). Of the boys and girls born in Africa or Asia, 31.6% and 34.6%, respectively, reported being bullied during the past week in schools with low (andlt; 10%) migrant density. Conclusions: Pupils born in Africa or Asia are at high risk for being bullied and having impaired well-being in schools with few other migrant children. School interventions to improve peer relations and prevent bullying are needed to promote well-being in non-European migrant children.
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| 20. |
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| 21. |
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| 22. |
- Kvashnina, K.O., et al.
(författare)
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Electronic structure of complex copper systems probed by resonant inelastic X-ray scattering at Cu L3 edge
- 2009
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Ingår i: Physica. B, Condensed matter. - : Elsevier B.V.. - 0921-4526 .- 1873-2135. ; 404:20, s. 3559-3566
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Tidskriftsartikel (refereegranskat)abstract
- We have used X-ray absorption (XA) and resonant inelastic X-ray scattering (RIXS) spectroscopies to study a series of copper compounds, namely Cu2O, CuO, Cu(OH)2, CuCl2, Cu2S, CuSO4, malachite (Cu2(CO3)2(OH)2) and atacamite (CuCl2·3Cu(OH)2). Cu 2p XA spectra provide information about oxidation states. Divalent copper gives a single narrow line due to excitations into the empty 3d state, whereas monovalent copper gives a broad band at higher energy due to transitions to 4s states. Chemical shifts of the main line in the Cu2+ XA spectra of different compounds are observed but in some cases they are too small to make a clear distinction between the species. It is shown that RIXS at the Cu 2p edge has a great potential to distinguish between the species due to large differences in spectral shapes for the same energy of the incident photon beam. First evidence for the possibility of detecting chemical composition of copper compounds is presented and discussed in details.
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| 23. |
- Kvashnina, Kristina O., et al.
(författare)
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In situ X-ray absorption study of copper films in ground water solutions
- 2007
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Ingår i: Chemical Physics Letters. - : Elsevier BV. - 0009-2614 .- 1873-4448. ; 447:1-3, s. 54-57
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Tidskriftsartikel (refereegranskat)abstract
- This study illustrates how the damage from copper corrosion can be reduced by modifying the chemistry of the copper surface environment. The surface modification of oxidized copper films induced by chemical reaction with Cl− and in aqueous solutions was monitored by in situ X-ray absorption spectroscopy. The results show that corrosion of copper can be significantly reduced by adding even a small amount of sodium bicarbonate. The studied copper films corroded quickly in chloride solutions, whereas the same solution containing 1.1 mM prevented or slowed down the corrosion processes.
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| 24. |
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| 25. |
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| 26. |
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| 27. |
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| 28. |
- Maurelli, M., et al.
(författare)
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Incompressible Euler equations with stochastic forcing: A geometric approach
- 2023
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Ingår i: Stochastic Processes and Their Applications. - : Elsevier BV. - 0304-4149. ; 159, s. 101-148
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Tidskriftsartikel (refereegranskat)abstract
- We consider a stochastic version of Euler equations using the infinite-dimensional geometric approach as pioneered by Ebin and Marsden (1970). For the Euler equations on a compact manifold (possibly with smooth boundary) we establish local existence and uniqueness of a strong solution in spaces of Sobolev mappings (of high enough regularity). Our approach combines techniques from stochastic analysis and infinite-dimensional geometry and provides a novel toolbox to establish local well-posedness of stochastic non-linear partial differential equations.(c) 2023 Elsevier B.V. All rights reserved.
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| 29. |
- Modin, A., et al.
(författare)
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Closed source experimental system for soft x-ray spectroscopy of radioactive materials
- 2008
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 79:9, s. 093103-
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Tidskriftsartikel (refereegranskat)abstract
- An instrumental and experimental setup for soft x-ray spectroscopy meeting the requirements of a closed source for radioactivity is described. The system consists of a vacuum sealed cell containing the sample, mounted on a tubing system to ensure compatibility with most standard manipulators. The soft x rays penetrate a thin x-ray window separating the interior of the cell from the vacuum in the experimental chamber. Our first results for single crystal PuO2 confirm the feasibility of experiments using the setup. The results are consistent with results of first principles calculations and previously recorded spectra obtained using a standard open source setup. The results show that the closed source experimental system can be used to collect valuable experimental data from radioactive materials.
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| 30. |
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| 31. |
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| 32. |
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| 33. |
- Modin, H, et al.
(författare)
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Genome-wide linkage screen of a consanguineous multiple sclerosis kinship
- 2003
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Ingår i: Multiple sclerosis (Houndmills, Basingstoke, England). - : SAGE Publications. - 1352-4585 .- 1477-0970. ; 9:2, s. 128-134
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Tidskriftsartikel (refereegranskat)abstract
- Multiple sclerosis (MS), like A lzheimer’s disease (A D) and Parkinson’s disease (PD), is a common neurological disorder thought to be caused by the interaction of several genes with unknown environmental factors. In both A D and PD the identification of disease forms inherited in a classic Mendelian fashion has helped investigators elucidate pathogenetic mechanisms. In this study a whole-genome screen, with an average of 608 successful genotypes per person, was performed on nine members of a consanguineous family: the index case, three of her siblings and her daughter, all of whom have been diagnosed with definite MS; as well as the parents of the index case (first cousins), one of her five healthy siblings and her husband (who is also her first cousin). Nonparametric linkage analysis was performed on genotyping data. Based on the presence of consanguinity, the a priori hypothesis was that the disease is transmitted in an autosomal recessive fashion in the pedigree. Linkage analysis revealed a suggestive logarithm of odds (LO D) score of 2.29 on the long arm of chromosome 9. Four of five affected family members were identically homozygous for a haplotype under this peak, spanning approximately 43 cM, while the fifth affected subject and all unaffected family members were hetero zygous for the haplotype.
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| 34. |
- Modin Larsson, Malin, 1980-, et al.
(författare)
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Antibody prevalence and titer to norovirus (genogroup II) correlate with secretor (FUT2) but not with ABO phenotype or Lewis (FUT3) genotype
- 2006
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Ingår i: J Infect Dis. - : Oxford University Press. ; 194:10, s. 1422-1427
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Tidskriftsartikel (refereegranskat)abstract
- BACKGROUND: Histo-blood group antigens and secretor status have been associated with susceptibility to Norovirus infections, which suggests that antibody prevalence and titer might correlate with these phenotypes. METHODS: Plasma samples (n = 105) from Swedish blood donors that had been genotyped for secretor (FUT2) and Lewis (Le; FUT3) genotypes and phenotyped for ABO and Le blood groups were analyzed for immunoglobulin G antibody prevalence and titers to norovirus genogroup (GG) II.4. RESULTS: The results showed that nonsecretors (se4128se428) and Lea+b- individuals not only had significantly lower antibody titers than did secretors (P < .0001) and Lea-b+ individuals (P < .0002) but were also significantly more often antibody negative (P < .05). Antibody titers in secretors were not significantly different between individuals of different Le (FUT3) genotypes or different ABO phenotypes. CONCLUSIONS: Nonsecretors and Lea+b- individuals are significantly less prone to be infected with GGII noroviruses. This new information extends previous knowledge and supports the hypothesis that nonsecretors are relatively but not absolutely resistant to norovirus infections.
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| 35. |
- Modin, Oskar, 1980, et al.
(författare)
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Bioelectrochemical hydrogen peroxide production – an opportunity for sustainable mitigation of membrane bioreactor fouling
- 2010
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Ingår i: Proceedings of the Biofilm Reactor Technology Conference, Portland, Oregon, USA, 2010. ; , s. 449-461
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Konferensbidrag (refereegranskat)abstract
- Membranes in membrane bioreactors (MBR) are typically cleaned with sodium hypochlorite. The latter is a strong oxidant and of concern due to the possible formation of chlorinated hydrocarbons. Here, we propose a new concept for chemical membrane cleaning with hydrogen peroxide (H2O2), generated onsite in a bioelectrochemical system. The energy present in the wastewater organics can be used to power the production process. We investigated bioelectrochemical H2O2 production from a synthetic wastewater in an inclinedbed reactor and discuss the possibility of using H2O2 to replace sodium hypochlorite for membrane cleaning. Low current, the use of carbon fiber as opposed to graphite, and low pH in the cathode all benefited H2O2 production. It was also possible to generate H2O2 with a net energy output, i.e. by operating the reactor as a microbial fuel cell. The highest H2O2concentration produced in this study was 176.3 mg/l, which was obtained at a production rate of 1.26 mg/h and an energy input of 0.32 kWh/kgH2O2. A concentration of 91.6 mg/l, a production rate of 0.54 mg/h and an energy output of 0.18 kWh/kgH2O2 was obtained when the reactor was operated as a microbial fuel cell. For application in a MBR, a relatively small portion (>3.8 mg/l BOD) of the influent organic compounds would have to be converted tocurrent by the electroactive bacteria living on the anode to produce sufficient amount of H2O2 for membrane cleaning. However, the produced H2O2 concentration must likely reach a concentration of 0.2-0.5%.
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| 36. |
- Modin, Oskar, 1980, et al.
(författare)
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Redistribution of wastewater alkalinity with a microbial fuel cell to support nitrification of reject water
- 2011
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Ingår i: Water Research. - : Elsevier BV. - 0043-1354 .- 1879-2448. ; 45:8, s. 2691-2699
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Tidskriftsartikel (refereegranskat)abstract
- In wastewater treatment plants, the reject water from the sludge treatment processes typically contains high ammonium concentrations, which constitute a significant internal nitrogen load in the plant. Often, a separate nitrification reactor is used to treat the reject water before it is fed back into the plant. The nitrification reaction consumes alkalinity, which has to be replenished by dosing e.g. NaOH or Ca(OH)(2). In this study, we investigated the use of a two-compartment microbial fuel cell (MFC) to redistribute alkalinity from influent wastewater to support nitrification of reject water. In an MFC, alkalinity is consumed in the anode compartment and produced in the cathode compartment. We use this phenomenon and the fact that the influent wastewater flow is many times larger than the reject water flow to transfer alkalinity from the influent wastewater to the reject water. In a laboratory-scale system, ammonium oxidation of synthetic reject water passed through the cathode chamber of an MFC, increased from 73.8 +/- 8.9 mgN/L under open-circuit conditions to 160.1 +/- 4.8 mgN/L when a current of 1.96 +/- 0.37 mA (15.1 mA/L total MFC liquid volume) was flowing through the MFC. These results demonstrated the positive effect of an MFC on ammonium oxidation of alkalinity-limited reject water.
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| 37. |
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| 38. |
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| 39. |
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| 40. |
- Rosfors, S, et al.
(författare)
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Laser Doppler Measurements of Systolic Blood Pressure on the First and Second Toe in Patients with Peripheral Arterial Disease
- 2022
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Ingår i: The International journal of angiology : official publication of the International College of Angiology, Inc. - : Georg Thieme Verlag KG. - 1061-1711. ; 31:1, s. 52-55
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Tidskriftsartikel (refereegranskat)abstract
- Laser Doppler was used to measure toe blood pressure (TBP) in 40 consecutive patients with various degree of peripheral arterial disease. The aim of this methodological study was to increase the usefulness of TBP by exploring the interchangeability between TBP from the first and second toe and by investigating daily routine reproducibility and measurement variability. According to our study design pressure values were based on three measurements that were averaged. At simultaneous measurements, TBP of the first toe was 71 mm Hg (standard deviation [SD] 25) compared with 70 mm Hg (SD 25) on the second toe. The correlation (r) between first and second toe pressure measurements was 0.84 and intraclass correlation coefficient (ICC) was 0.84. The difference between TBP on the first and second toe was not related to gender, diabetes, or magnitude of the pressures. Repeated TBP measurements of the right first toe after disconnection of cuffs, 5 to 10 minutes rest, and reconnection of cuffs had a coefficient of variation (CV) of 9% and an ICC of 0.93. CV for toe-brachial index (TBI) was 8%. Our results show that measurements of TBP from the second toe to a large extent are interchangeable with those assessed from the first toe and can be used in clinical situations where measurements from the first toe are not feasible. Flow detection with three averaged laser Doppler measurements generates TBP and TBI with low variability.
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| 41. |
- Sandelowsky, H, et al.
(författare)
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Patient outcomes following GPs' educations about COPD: a cluster randomized controlled trial
- 2020
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Ingår i: NPJ primary care respiratory medicine. - : Springer Science and Business Media LLC. - 2055-1010. ; 30:1, s. 44-
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Tidskriftsartikel (refereegranskat)abstract
- This study aimed to compare patient outcomes following case method learning and traditional lectures as methods for continuing medical education (CME) about chronic obstructive pulmonary disease (COPD) for general practitioners (GPs) in Sweden. In a pragmatic cluster randomized controlled trial, COPD patients (n = 425; case method group n = 209, traditional lectures group n = 216) from 24 primary health care centers replied to questionnaires prior to and 18 months after a 2 × 2-h CME was given to GPs (n = 255). We measured changes in the scores of the Clinical COPD Questionnaire (CCQ), symptoms, needs for disease information, exacerbations, smoking, and use of pulmonary rehabilitation. The changes over time were similar for both CME methods. Patients who had used pulmonary rehabilitation increased from 13.2 to 17.8% (P = 0.04), and prevalence of smoking decreased from 28.9 to 25.1% (P = 0.003). In conclusion, neither of the used CME methods was superior than the other regarding patient outcomes. CME’s primary value may lay in improving GPs’ adherence to guidelines, which should lead to long-term positive changes in patient health.
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| 42. |
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| 43. |
- Suarez, Carolina, et al.
(författare)
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Disturbance-based management of ecosystem services and disservices in partial nitritation-anammox biofilms
- 2022
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Ingår i: npj Biofilms and Microbiomes. - : Springer Science and Business Media LLC. - 2055-5008. ; 8:1
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Tidskriftsartikel (refereegranskat)abstract
- The resistance and resilience provided by functional redundancy, a common feature of microbial communities, is not always advantageous. An example is nitrite oxidation in partial nitritation-anammox (PNA) reactors designed for nitrogen removal in wastewater treatment, where suppression of nitrite oxidizers like Nitrospira is sought. In these ecosystems, biofilms provide microhabitats with oxygen gradients, allowing the coexistence of aerobic and anaerobic bacteria. We designed a disturbance experiment where PNA biofilms, treating water from a high-rate activated sludge process, were constantly or intermittently exposed to anaerobic sidestream wastewater, which has been proposed to inhibit nitrite oxidizers. With increasing sidestream exposure we observed decreased abundance, alpha-diversity, functional versatility, and hence functional redundancy, among Nitrospira in the PNA biofilms, while the opposite patterns were observed for anammox bacteria within Brocadia. At the same time, species turnover was observed for aerobic ammonia-oxidizing Nitrosomonas populations. The different exposure regimens were associated with metagenomic assembled genomes of Nitrosomonas, Nitrospira, and Brocadia, encoding genes related to N-cycling, substrate usage, and osmotic stress response, possibly explaining the three different patterns by niche differentiation. These findings imply that disturbances can be used to manage the functional redundancy of biofilm microbiomes in a desirable direction, which should be considered when designing operational strategies for wastewater treatment.
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| 44. |
- Öborn, Ingrid, et al.
(författare)
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A systems approach to assess farm-scale nutrient and trace element dynamics: A case study at the Ojebyn dairy farm
- 2005
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Ingår i: Ambio: a Journal of Human Environment. - 0044-7447 .- 1654-7209. ; 34:4, s. 301-310
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Tidskriftsartikel (refereegranskat)abstract
- A systems analysis approach was used to assess farmscale nutrient and trace element sustainability by combining full-scale field experiments with specific studies of nutrient release from mineral weathering and trace-element cycling. At the Ojebyn dairy farm in northern Sweden, a farm-scale case study including phosphorus (P), potassium (K), and zinc (Zn) was run to compare organic and conventional agricultural management practices. By combining different element-balance approaches (at farmgate, barn, and field scales) and further adapting these to the FARMFLOW model, we were able to combine mass flows and pools within the subsystems and establish links between subsystems in order to make farm-scale predictions. It was found that internal element flows on the farm are large and that there are farm internal sources (Zn) and loss terms (K). The approaches developed and tested at the Ojebyn farm are promising and considered generally adaptable to any farm.
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