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| 2. |
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| 3. |
- Ciavola, G., et al.
(författare)
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Status report of the MS-ECRIS construction
- 2007
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Ingår i: High Energy Physics & Nuclear Physics - Chinese Edition. - 0254-3052. ; 31, s. 13-17
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Tidskriftsartikel (refereegranskat)abstract
- The design of each component of the Multipurpose Superconducting ECR Ion Source (MS-ECRIS) has been completed and some items are ready. The magnets and the cryostat are under construction at ACCEL and the commissioning is scheduled for March 2007. The mechanical have been optimized and their construction is under way, the microwave system is under refurbishment and the 65kV power supply is available and upgraded for afterglow operations. Pumping and extraction system were adapted to the EIS testbench of GSI Darmstadt. The description of,each part will be given in the paper along with a schedule of the forthcoming development and experiments.
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| 4. |
- Kumarathunge, Dushan P., et al.
(författare)
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Acclimation and adaptation components of the temperature dependence of plant photosynthesis at the global scale
- 2019
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Ingår i: New Phytologist. - : John Wiley & Sons. - 0028-646X .- 1469-8137. ; 222:2, s. 768-784
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Tidskriftsartikel (refereegranskat)abstract
- The temperature response of photosynthesis is one of the key factors determining predicted responses to warming in global vegetation models (GVMs). The response may vary geographically, owing to genetic adaptation to climate, and temporally, as a result of acclimation to changes in ambient temperature. Our goal was to develop a robust quantitative global model representing acclimation and adaptation of photosynthetic temperature responses.We quantified and modelled key mechanisms responsible for photosynthetic temperature acclimation and adaptation using a global dataset of photosynthetic CO2 response curves, including data from 141 C3 species from tropical rainforest to Arctic tundra. We separated temperature acclimation and adaptation processes by considering seasonal and common-garden datasets, respectively.The observed global variation in the temperature optimum of photosynthesis was primarily explained by biochemical limitations to photosynthesis, rather than stomatal conductance or respiration. We found acclimation to growth temperature to be a stronger driver of this variation than adaptation to temperature at climate of origin.We developed a summary model to represent photosynthetic temperature responses and showed that it predicted the observed global variation in optimal temperatures with high accuracy. This novel algorithm should enable improved prediction of the function of global ecosystems in a warming climate.
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| 5. |
- Battaglia-Brunet, F., et al.
(författare)
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Characterization of an agricultural site historically polluted by the destruction of arsenic-containing chemical weapons
- 2018
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Ingår i: Environmental Arsenic in a ChangingWorld - 7th International Congress and Exhibition Arsenic in the Environment, 2018. - London : CRC Press/Balkema. - 9781138486096 ; , s. 241-242
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Konferensbidrag (refereegranskat)abstract
- Arsenic in agricultural soils may represent a risk for crop quality and surrounding water resources. In the frame of AgriAs project, “Evaluation and management of Arsenic contamination in agricultural soil and water”, a former chemical weapons destruction site converted into agricultural land was characterized. The objective of this study was to identify possible links between arsenic concentration and speciation and bioindicators informing about the bioavailability of the toxic element. Plants lipidic bio-indicator Omega-3 Index showed that toxicity of the soil was not directly correlated with arsenic concentration. Conversely, arsenic level in the soil samples seemed to influence the density of microbes transforming As species.
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| 6. |
- Hämäläinen, Jari, et al.
(författare)
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Multiobjective Decision Making for Papermaking
- 2004
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Ingår i: CD-Proceedings of MCDM2004, the 17th International Conference on Multiple Criteria Decision Making.
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Konferensbidrag (övrigt vetenskapligt/konstnärligt)
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| 7. |
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| 8. |
- Lin, Yan-Shih, et al.
(författare)
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Optimal stomatal behaviour around the world
- 2015
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Ingår i: Nature Climate Change. - : Springer Science and Business Media LLC. - 1758-678X .- 1758-6798. ; 5, s. 459-464
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Tidskriftsartikel (refereegranskat)abstract
- Stomatal conductance (gs) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of gs in predictions of global water and carbon cycle changes, a globalscale database and an associated globally applicable model of gs that allow predictions of stomatal behaviour are lacking. Here,we present a database of globally distributed gs obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model1 and the leaf and wood economics spectrum2,3.We also demonstrate a global relationship with climate. These findings provide a robust theoretical framework for understanding and predicting the behaviour of gs across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate.
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| 9. |
- Lin, Yan-Shih, et al.
(författare)
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Optimal stomatal behaviour around the world
- 2015
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Ingår i: Nature Climate Change. - 1758-6798 .- 1758-678X. ; 5:5, s. 459-464
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Tidskriftsartikel (refereegranskat)abstract
- Stomatal conductance (g(s)) is a key land-surface attribute as it links transpiration, the dominant component of global land evapotranspiration, and photosynthesis, the driving force of the global carbon cycle. Despite the pivotal role of g(s) in predictions of global water and carbon cycle changes, a global-scale database and an associated globally applicable model of g(s) that allow predictions of stomatal behaviour are lacking. Here, we present a database of globally distributed g(s) obtained in the field for a wide range of plant functional types (PFTs) and biomes. We find that stomatal behaviour differs among PFTs according to their marginal carbon cost of water use, as predicted by the theory underpinning the optimal stomatal model(1) and the leaf and wood economics spectrum(2,3). We also demonstrate a global relationship with climate. These findin g(s) provide a robust theoretical framework for understanding and predicting the behaviour of g(s) across biomes and across PFTs that can be applied to regional, continental and global-scale modelling of ecosystem productivity, energy balance and ecohydrological processes in a future changing climate.
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| 10. |
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| 11. |
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| 12. |
- De Kauwe, M. G., et al.
(författare)
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A test of the ‘one-point method’ for estimating maximum carboxylation capacity from field-measured, light-saturated photosynthesis
- 2016
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Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 210:3, s. 1130-1144
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Tidskriftsartikel (refereegranskat)abstract
- Simulations of photosynthesis by terrestrial biosphere models typically need a specification of the maximum carboxylation rate (Vcmax). Estimating this parameter using A–Ci curves (net photosynthesis, A, vs intercellular CO2 concentration, Ci) is laborious, which limits availability of Vcmax data. However, many multispecies field datasets include net photosynthetic rate at saturating irradiance and at ambient atmospheric CO2 concentration (Asat) measurements, from which Vcmax can be extracted using a ‘one-point method’. We used a global dataset of A–Ci curves (564 species from 46 field sites, covering a range of plant functional types) to test the validity of an alternative approach to estimate Vcmax from Asat via this ‘one-point method’. If leaf respiration during the day (Rday) is known exactly, Vcmax can be estimated with an r2 value of 0.98 and a root-mean-squared error (RMSE) of 8.19 μmol m−2 s−1. However, Rday typically must be estimated. Estimating Rday as 1.5% of Vcmax, we found that Vcmax could be estimated with an r2 of 0.95 and an RMSE of 17.1 μmol m−2 s−1. The one-point method provides a robust means to expand current databases of field-measured Vcmax, giving new potential to improve vegetation models and quantify the environmental drivers of Vcmax variation.
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| 13. |
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| 14. |
- Janhunen, P., et al.
(författare)
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Invited Article: Electric solar wind sail : Toward test missions
- 2010
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Ingår i: Review of Scientific Instruments. - : AIP Publishing. - 0034-6748 .- 1089-7623. ; 81:11, s. 111301-
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Tidskriftsartikel (refereegranskat)abstract
- The electric solar wind sail (E-sail) is a space propulsion concept that uses the natural solar wind dynamic pressure for producing spacecraft thrust. In its baseline form, the E-sail consists of a number of long, thin, conducting, and centrifugally stretched tethers, which are kept in a high positive potential by an onboard electron gun. The concept gains its efficiency from the fact that the effective sail area, i.e., the potential structure of the tethers, can be millions of times larger than the physical area of the thin tethers wires, which offsets the fact that the dynamic pressure of the solar wind is very weak. Indeed, according to the most recent published estimates, an E-sail of 1 N thrust and 100 kg mass could be built in the rather near future, providing a revolutionary level of propulsive performance (specific acceleration) for travel in the solar system. Here we give a review of the ongoing technical development work of the E-sail, covering tether construction, overall mechanical design alternatives, guidance and navigation strategies, and dynamical and orbital simulations.
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| 15. |
- Kajos, M. K., et al.
(författare)
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Terpenoid emissions from fully grown east Siberian Larix cajanderi trees
- 2013
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Ingår i: Biogeosciences. - : Copernicus GmbH. - 1726-4189. ; 10:7, s. 4705-4719
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Tidskriftsartikel (refereegranskat)abstract
- While emissions of many biogenic volatile organic compounds (BVOCs), such as terpenoids, have been studied quite intensively in North American and Scandinavian boreal forests, the vast Siberian boreal forests have remained largely unexplored by experimental emission studies. In this study the shoot-scale terpenoid emission rates from two mature Larix cajanderi trees growing in their natural habitat in eastern Siberia were measured at the Spasskaya Pad flux measurement site (62 degrees 15'18.4 '' N, 129 degrees 37'07.9 '' E) located on the western bank of the Lena river. The measurements were conducted during three campaigns: 3-24 June, 8-26 July, and 14-30 August, in the summer of 2009. A dynamic flow-through enclosure technique was applied for adsorbent sampling, and the samples were analysed offline with a gas chromatograph. Between 29 and 45 samples were taken from each shoot during all three campaigns. Seven different monoterpenes, six different sesquiterpenes, linalool isoprene, and 2-methyl-3-buten-2-ol (MBO) were identified. The monthly median value of the total terpenoid emissions varied between 0.006 and 10.6 mu g g(dw)(-1)h(-1). The emissions were dominated by monoterpenes, which constituted between 61 and 92% of the total emissions. About half of the monoterpene emissions were comprised of Delta(3)-carene; alpha- and beta-pinene had significant emissions as well. Linalool emissions were also substantial, comprising 3-37% of the total emissions, especially in June. Sesquiterpenes accounted for less than 3% and isoprene less than 1% of the total emissions. Based on the measured emission rates, the relative atmospheric concentration of each compound was estimated. Monoterpenes were the species with the highest relative concentration, while linalool and sesquiterpenes had a notably smaller contribution to the estimated atmospheric concentration than to the emission rates. A temperature-dependent pool algorithm with a constant beta (0.09 degrees C-1 for monoterpenes and 0.143 degrees C-1 for sesquiterpenes) was used to normalize the measured emission data. For monoterpenes the emission potential varied between 0.5 and 18.5 mu g g(dw)(-1)h(-1) and for sesquiterpenes between 0.02 and 0.4 mu g g(dw)(-1)h(-1).
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| 16. |
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| 17. |
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| 18. |
- Markkola, A.M., et al.
(författare)
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Estimates of fungal biomass in Scots pine stands on an urban pollution gradient
- 1995
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Ingår i: New Phytologist. - : Wiley. - 0028-646X .- 1469-8137. ; 131:1, s. 139-147
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Tidskriftsartikel (refereegranskat)abstract
- Biomasses of ectomycorrhizal and saprotrophic fungal communities partitioned into sporophores and non‐reproductive structures were estimated in mature Scots pine (Pinus sylvestris L.) stands along an urban nitrogen and sulphur pollution gradient in northern Finland. The average total biomass of fungi varied in the four pollution zones from 14.6 to 20.2 g d. Wt kg−1 soil d. wt and from 73.3 to 108.0 g d. Wt m−2, the mycelia of both mycorrhizai and saprotrophic fungi in the soil comprising 72–80% of the total. The annual carbon allocation to the fungal communities was calculated to vary between 9 and 26% of the estimated annual carbon assimilation at the Scots pine sites. The size of the mean fungal biomass fractions decreased in the following sequence: mycelia in the soil > fungal biomass in fine roots estimated in terms of chitin > sclerotia > fungal biomass in fine roots estimated in terms of ergosterol > sporopbores of mycorrhizal fungi > sporophores of saprotrophie fungi. A positive correlation was obtained between the number of Scots pine mycorrhiza and the average sporophore yield of mvcorrhiaal fungi for three successive years. Tbe sporophore biomass of the mycorrhizal fungi was smaller at the most polluted than at the least polluted sites. The total fungal biomass allocation was not affected by urban pollution.
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| 19. |
- Markkola, A. M, et al.
(författare)
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Urban polluted forest soils induce elevated root peroxidase activity in Scots pine (Pinus sylvestris L.) seedlings
- 2002
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Ingår i: Environmental Pollution. - 0269-7491 .- 1873-6424. ; 116:2, s. 273-278
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Tidskriftsartikel (refereegranskat)abstract
- Plant biomass, mycorrhizal status and root peroxidase activity were measured in ectomycorrhizal Scots pine (Pinus sylvestris L.) seedlings grown in urban polluted and native, non-polluted forest soils with added ammonium or potassium sulphates simulating N and S deposition of urban areas. Peroxidase activity in the fine roots of seedlings planted in polluted forest soils was higher than in those planted in non-polluted soils and correlated positively with the activities measured in an earlier study in the roots of mature Scots pines growing at the sites from where the soils were collected. Growth of seedlings and mycorrhizal status were not affected by the origin of soil. Exposing the seedlings to winter acclimation conditions for 6 weeks elevated peroxidase activity in the roots. The addition of ammonium or potassium sulphate to non-polluted soils did not induce elevated root peroxidase activity, although at the levels of 0.5 and 1.0 g of ammonium sulphate a slight increasing trend was observed. We suggest, that indirect biotic factors, i.e. changes in the community structure of soil fungi, early stages of recognition, and defence reactions of pine roots against saprophytic and pathogenic fungi may be participating in the elicitation of peroxidase (POD) activity, although the possible role of heavy metals cannot be excluded.
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| 20. |
- Nordin, Angelica, et al.
(författare)
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Sequence variations in C9orf72 downstream of the hexanucleotide repeat region and its effect on repeat-primed PCR interpretation : a large multinational screening study
- 2017
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Ingår i: Amyotrophic Lateral Sclerosis and Frontotemporal Degeneration. - : Informa UK Limited. - 2167-8421 .- 2167-9223. ; 18:3-4, s. 256-264
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Tidskriftsartikel (refereegranskat)abstract
- A large GGGGCC-repeat expansion mutation (HREM) in C9orf72 is the most common known cause of ALS and FTD in European populations. Sequence variations immediately downstream of the HREM region have previously been observed and have been suggested to be one reason for difficulties in interpreting RP-PCR data. Our objective was to determine the properties of these sequence variations with regard to prevalence, the range of variation, and effect on disease prognosis. We screened a multi-national cohort (n = 6981) for the HREM and samples with deviant RP-PCR curves were identified. The deviant samples were subsequently sequenced to determine sequence alteration. Our results show that in the USA and European cohorts (n = 6508) 10.7% carried the HREM and 3% had a sequence variant, while no HREM or sequence variants were observed in the Japanese cohort (n = 473). Sequence variations were more common on HREM alleles; however, certain population specific variants were associated with a non-expanded allele. In conclusion, we identified 38 different sequence variants, most located within the first 50 bp downstream of the HREM region. Furthermore, the presence of an HREM was found to be coupled to a lower age of onset and a shorter disease survival, while sequence variation did not have any correlation with these parameters.
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| 21. |
- Smith, N. G., et al.
(författare)
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Global photosynthetic capacity is optimized to the environment
- 2019
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Ingår i: Ecology Letters. - : Wiley. - 1461-023X .- 1461-0248. ; 22:3, s. 506-517
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Tidskriftsartikel (refereegranskat)abstract
- Earth system models (ESMs) use photosynthetic capacity, indexed by the maximum Rubisco carboxylation rate (V-cmax), to simulate carbon assimilation and typically rely on empirical estimates, including an assumed dependence on leaf nitrogen determined from soil fertility. In contrast, new theory, based on biochemical coordination and co-optimization of carboxylation and water costs for photosynthesis, suggests that optimal V-cmax can be predicted from climate alone, irrespective of soil fertility. Here, we develop this theory and find it captures 64% of observed variability in a global, field-measured V-cmax dataset for C-3 plants. Soil fertility indices explained substantially less variation (32%). These results indicate that environmentally regulated biophysical constraints and light availability are the first-order drivers of global photosynthetic capacity. Through acclimation and adaptation, plants efficiently utilize resources at the leaf level, thus maximizing potential resource use for growth and reproduction. Our theory offers a robust strategy for dynamically predicting photosynthetic capacity in ESMs.
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| 22. |
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| 23. |
- Tarvainen, O, et al.
(författare)
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Changes in Ectomycorrhizal Colonization and Root Peroxidase Activity in Pinus sylvestris Nursery Seedlings Planted in Forest Humus
- 2004
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Ingår i: Scandinavian Journal of Forest Research. - : Informa UK Limited. - 0282-7581 .- 1651-1891. ; 19:5, s. 400-408
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Tidskriftsartikel (refereegranskat)abstract
- Plant biomass, root colonization by ectomycorrhizal (ECM) fungi and root peroxidase (POD) activity were monitored in Scots pine (Pinus sylvestris L.) nursery seedlings during the first growing season after planting (after 4, 8 and 16 weeks, in July, August and October, respectively) in forest humus in outdoor open-top chambers with gaseous atmospheric pollutants (combinations of low levels of ozone, sulfur dioxide and nitrogen oxides). The number of ECM morphotypes as well as root biomass increased towards the end of the growing season, while root POD activity decreased. Fungal biomass estimated as ergosterol concentration peaked in August, 8 weeks after planting. The seedling growth, mycorrhizal status and POD activity in the roots were not affected by the gaseous pollutants.
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