WorldWideScience

Sample records for matter som pools

  1. SOM storage and pool distribution in forest soils along climatic and altitudinal gradients across Switzerland

    Science.gov (United States)

    Gosheva, Sia; Müller, Mirjam; Walthert, Lorenz; Zimmermann, Stephan; Niklaus, Pascal A.; González Domínguez, Beatriz R.; Abiven, Samuel; Hagedorn, Frank

    2016-04-01

    Soil organic matter (SOM) plays a key role for a number of soil and ecosystem functions. Yet our quantitative understanding of the main driving factors is uncertain. SOM consists of a continuum of compounds ranging from slightly altered plant residues, known as particulate OM (POM) to mineral-associated OM (mOM). POM is the most rapidly cycling and hence vulnerable fraction of SOM. Therefore, it might respond particularly sensitive to climate change. In grassland soils, SOM content as well as the contribution of POM was found to increase with increasing elevation, which suggests that climate exerts a major control on SOM stability and storage. Little is known, however, for forest soils where a substantial fraction of POM is stored in the organic layer. In our study based on 1000 soil profiles, we explore the controlling factors of SOM stocks and the distribution of POM in the organic layer as well as within mineral soils in forests across Switzerland. We hypothesize that (i) elevation and hence climate have rather negligible effects on carbon (C) stocks, but exert large effects on SOM quality (contribution of POM, SOM depth distribution, and C/N ratio); (ii) furthermore, we postulate to find an elevational effect on C stocks in the organic layer but not in the mineral soil. We examined SOM stocks in the organic layer and the mineral soil of 1000 soil profiles. Mineral soils (0-20cm) from a subset of 54 sites were separated into free light fraction and occluded light fraction, representing POM, while fine heavy fraction and coarse heavy fraction represented the mineral-associated OM. The sites, all located in Swiss forests, were distributed along a great elevational gradient ranging between 277 and 2207 m a.s.l., and spanning a gradient in mean annual temperatures (MAT) from 0.6 to 11.9 °C, and mean annual precipitation (MAP) from 704 to 2340 mm. Our results indicate that POM and C/N ratio are more closely related to elevation and climate compared to mOM. For C

  2. Impact of Fe(III)-OM complexes and Fe(III) polymerization on SOM pools reactivity under different land uses

    Science.gov (United States)

    Giannetta, B.; Plaza, C.; Zaccone, C.; Siebecker, M. G.; Rovira, P.; Vischetti, C.; Sparks, D. L.

    2017-12-01

    Soil organic matter (SOM) protection and long-term accumulation are controlled by adsorption to mineral surfaces in different ways, depending on its molecular structure and pedo-climatic conditions. Iron (Fe) oxides are known to be key regulators of the soil carbon (C) cycle, and Fe speciation in soils is highly dependent on environmental conditions and chemical interactions with SOM. However, the molecular structure and hydrolysis of Fe species formed in association with SOM is still poorly described. We hypothesize the existence of two pools of Fe which interact with SOM: mononuclear Fe(III)-SOM complexes and precipitated Fe(III) hydroxides. To verify our hypothesis, we investigated the interactions between Fe(III) and physically isolated soil fractions by means of batch experiments at pH 7. Specifically, we examined the fine silt plus clay (FSi+C) fraction, obtained by ultrasonic dispersion and wet sieving. The soil samples spanned several land uses, including coniferous forest (CFS), grassland (GS), technosols (TS) and agricultural (AS) soils. Solid phase products and supernatants were analyzed for C and Fe content. X-ray diffraction (XRD) and Brunauer-Emmett-Teller (BET) analysis were also performed. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) was used to assess the main C functional groups involved in C complexation and desorption experiments. Preliminary linear combination fitting (LCF) of Fe K-edge extended X-ray absorption fine structure (EXAFS) spectra suggested the formation of ferrihydrite-like polymeric Fe(III) oxides in reacted CFS and GS samples, with higher C and Fe concentration. Conversely, mononuclear Fe(III) OM complexes dominated the speciation for TS and AS samples, characterized by lower C and Fe concentration, inhibiting the hydrolysis and polymerization of Fe (III). This approach will help revealing the mechanisms by which SOM pools can control Fe(III) speciation, and will elucidate how both Fe

  3. Effect of variable soil texture, metal saturation of soil organic matter (SOM) and tree species composition on spatial distribution of SOM in forest soils in Poland.

    Science.gov (United States)

    Gruba, Piotr; Socha, Jarosław; Błońska, Ewa; Lasota, Jarosław

    2015-07-15

    In this study we investigated the effect of fine (ϕclay (FF) content in soils, site moisture, metal (Al and Fe) of soil organic matter (SOM) and forest species composition on the spatial distribution of carbon (C) pools in forest soils at the landscape scale. We established 275 plots in regular 200×200m grid in a forested area of 14.4km(2). Fieldwork included soil sampling of the organic horizon, mineral topsoil and subsoil down to 40cm deep. We analysed the vertical and horizontal distribution of soil organic carbon (SOC) stocks, as well as the quantity of physically separated fractions including the free light (fLF), occluded light (oLF) and mineral associated fractions (MAF) in the mineral topsoil (A, AE) horizons. Distribution of C in soils was predominantly affected by the variation in the FF content. In soils richer in the FF more SOC was accumulated in mineral horizons and less in the organic horizons. Accumulation of SOC in mineral soil was also positively affected by the degree of saturation of SOM with Al and Fe. The increasing share of beech influenced the distribution of C stock in soil profiles by reducing the depth of O horizon and increasing C stored in mineral soil. The content of FF was positively correlated with the content of C in MAF and fLF fractions. The content of oLF and MAF fractions was also positively influenced by a higher degree of metal saturation, particularly Al. Our results confirmed that Al plays an important role in the stabilization of SOM inside aggregates (CoLF) and as in CMAF fractions. We also found a significant, positive effect of beech on the CfLF and fir on the CoLF content. Copyright © 2015 Elsevier B.V. All rights reserved.

  4. Soil organic matter (SOM) dynamics determined by stable isotope techniques

    International Nuclear Information System (INIS)

    Gerzabek, M. H.

    1998-09-01

    Being aware of limitations and possible bias the 13 C natural abundance technique using the different 13 C enrichments in plants with differing photosynthetic pathways in a powerful tool to quantify turnover processes, both in long-term field studies and short-term laboratory experiments. Special care is needed in choosing reference plots and the proper number of replicate samples. The combination of 13 C and 14 C measurements has a high potential for a further improvement of isotope techniques in SOM studies. Natural abundance of 15 N is less powerful with respect to quantification of SOM processes than the isotope dilution technique. However its usefulness could be distinctly improved by introducing other stable isotopes into the studies.(author)

  5. Effect of microbial enzyme allocation strategies on stoichiometry of soil organic matter (SOM) decomposition

    Science.gov (United States)

    Wutzler, Thomas

    2014-05-01

    We explored different strategies of soil microbial community to invest resources into extracellular enzymes by conceptual modelling. Similar to the EEZY model by Moorhead et al. (2012), microbial community can invest into two separate pools of enzymes that depolymerize two different SOM pools. We show that with assuming that a fixed fraction of substrate uptake is allocated to enzymes, the microbial dynamics decouples from decomposition dynamics. We propose an alternative formulation where investment into enzymes is proportional to microbial biomass. Next, we show that the strategy of optimizing stoichiometry of decomposition flux according to microbial biomass stoichiometry yield less microbial growth than the strategy of optimizing revenue of the currently limiting element. However, both strategies result in better usage of the resources, i.e. less C overflow or N mineralization, than the strategy of equal allocation to both enzymes. Further, we discuss effects of those strategies on decomposition of SOM and priming at different time scales and discuss several abstractions from the detailed model dynamics for usage in larger scale models.

  6. How the type of pyrogenic organic matter determines the SOM quality in amended soils

    Science.gov (United States)

    Merino, Agustin; Gartzia-Bengoetxea, Nahia; Morangues, Lur; Arias-Gonzalez, Ander

    2016-04-01

    Charred biomass can be used as an organic amendment and to enhance the C sink capacity of soils. There are two types of by-products containing pyrogenic OM that could be used to improve in agricultural or forestry, biochar and wood ash. Due to their different heating conditions under which it is produced (pyrolysis, combustion and different temperatures, feedstocks,..), the properties of this pyrogenic OM might be highly variable, which could affect the SOM quality and the C sink capacity of the amended soil. The purpose of this study was to assess how SOM quality is influenced by pyrogenic organic matter with different degree of carbonization. Biochar and bottom wood ash were added to two Atlantic forest soils (Pinus radiata, 12 °C, 1200 mm) with different texture, clayey loam and sandy loam. The experiment consisted in a randomized block trials, in which different doses of biochar (0, 3, 9, 18 Mh ha-1) and wood ash (0, 1.5, 4.5, and 9 Mg ha-1) were added. The Biochar applied (pH: 9.8; C: 87 %) was produced by the pyrolysis of Myscanthus sp. at 450°C in a Pyreg® pyrolysis unit. The bottom wood ash (pH: 10.6; C: 30 %) was produced by combustion in a biomass power plant. The aromatization/carbonization was lightly higher in biochar than in wood ash. This latter by-product, in addition to the black carbon, it also contained mineral ash, as well as unburnt or lightly charred plant biomass. The evolution of soil chemical and SOM properties were monitored over three years by solid state Differential Scanning Calorimetry (DSC) and 13C CPMAS NMR. These techniques were applied in bulk samples and also in fractions of different densityes. The changes in microbial activity were studied by analysis of microbial biomass C and basal respiration and soil microbial community. Three years after applications the SOM content increased lightly in the treatment receiving the highest doses of biochar and wood ash, specially in the clay loam soil. SOM in the treated soils displayed a

  7. From Turnover-Oriented to Functional Soil Organic Matter Pools: a Lesson Learned from Stable Isotope Tracing

    Science.gov (United States)

    Cotrufo, M. F.

    2016-12-01

    Globally soils contain three times the amount of carbon (C) stored in the atmosphere, and 68% of this is stored in soil below 30cm. Changes to the size of the soil C stocks could significantly impact the net terrestrial-atmosphere CO2 exchange and thus either mitigate or increase concentrations of CO2. Yet we are currently unable to conduct reliable predictions of the direction and magnitude of soil C stock changes, since current soil C models fail to accurately capture the current understanding of how soil organic matter (SOM) forms and persists, and (2) the vertical movement and deep soil processing of SOM. We propose shifting soil C modelling approaches from a turnover-oriented approach to a more functional-oriented approach, where measurable SOM pools with specific function in soils, with respect to their physical structure (soluble versus particulate), microbial accessibility (free versus mineral or aggregate protection) and ability to transfer along the soil profile (through water flow or by mass transport) are represented. We will present experimental evidence from a number of studies conducted in the past few years using stable isotope tracing in support of incorporating a dissolved organic matter (DOM)-microbial path and a physical transfer of particulate organic matter path in SOM models. We will also show how, through the DOM-microbial path, fresh plant inputs quickly result in the formation of new mineral-associated organic matter.

  8. RICCI and matter collineations of som-roy chaudhary symmetric space time

    International Nuclear Information System (INIS)

    Ramzan, M.; Ahmed, Y.; Mufti, M.

    2018-01-01

    This paper is devoted to explore the RICCI and MCs (Matter Collineations of the Som-Ray Chaudhary spacetime. The spacetime under consideration is one of the spatially homogeneous and rotating spacetimes. Collineations are the some kinds of the Lie symmetries. To discuss the required collineations we have used the RICCI and energy momentum tensors. As the RICCI tensor is formulated from the metric tensor, it must possess its symmetries. RCs (RICCI Collineations) leads to conservation laws. On the other hand for the distribution of matter in the spacetimes, the symmetries of energy momentum tensor or MCs provides conservation laws on matter field. Throughout this paper, these collineations are discussed by vanishing Lie derivative of RICCI and energy momentum tensors respectively. Complete solution of the RCs and MCs equations, which are formed in the result of vanishing Lie derivative are explored. Studying all these collineations in the said spacetime, it has been shown that RCs of the spacetime form an infinite dimensional vector space where as MCs are Killing vector fields. (author)

  9. Relationships between soil organic matter pools and nitrous oxide emissions of agroecosystems in the Brazilian Cerrado.

    Science.gov (United States)

    de Figueiredo, Cícero Célio; de Oliveira, Alexsandra Duarte; Dos Santos, Isis Lima; Ferreira, Eloisa Aparecida Belleza; Malaquias, Juaci Vitoria; de Sá, Marcos Aurélio Carolino; de Carvalho, Arminda Moreira; Dos Santos, João de Deus Gomes

    2018-03-15

    In the Brazilian Cerrado, despite the increasing adoption of no-till systems, there are still extended areas under conventional soil management systems that reduce soil carbon (C) and nitrogen (N) stocks and increase the emissions of greenhouse gases, such as nitrous oxide (N 2 O). Conservation agroecosystems, such as no-till, have been proposed as a strategy to mitigate agriculture-induced climatic changes through reductions in N 2 O emissions. However, the relationship between organic matter and N 2 O emissions from soils under different agroecosystems is not yet clear. This study hypothesized that agroecosystems under no-till promote an accumulation of labile and stable SOM fractions along with a reduction of N 2 O emissions. This study evaluated the effects of crop-rotation agroecosystems: i) on C and N pools and labile and stable SOM fractions; ii) on cumulative N 2 O emissions; and iii) on the relationships between SOM fractions and N 2 O emissions. The agricultural systems consisted of: (I) soybean followed by sorghum under no-tillage (NT1); (II) maize followed by pigeon pea under no-tillage (NT2); (III) soybean under conventional tillage followed by fallow soil (CT); (IV) and native Cerrado (CER). After CT for 18years, following the replacement of CER, the soil C stock in the 0-20cm layer was reduced by 0.64tha -1 year -1 . The no-till systems were more efficient in accumulating labile and stable C fractions with values close to those observed under CER, and were directly related to lower soil N 2 O emissions. The cumulative pattern of N 2 O emissions was inverse to that of the following SOM fractions: microbial biomass carbon, permanganate-oxidizable carbon, particulate organic carbon, inert carbon, and humic substances. Based on principal component analysis, the CT was generally separated from the other land use systems. This separation was strongly influenced by the low C contents in the different SOM fractions and higher N 2 O emissions promoted by the

  10. Toward a Simple Framework for Understanding the Influence of Litter Quality on Vertical and Horizontal Patterns of Soil Organic Matter Pools

    Science.gov (United States)

    Craig, M.; Phillips, R.

    2016-12-01

    Decades of research have revealed that plant litter quality fundamentally influences soil organic matter (SOM) properties. Yet we lack the predictive frameworks necessary to up-scale our understanding of these dynamics in biodiverse systems. Given that ectomycorrhizal (EM) and arbuscular mycorrhizal (AM) plants are thought to differ in their litter quality, we ask whether this dichotomy represents a framework for understanding litter quality effects on SOM in temperate forests. To do this, we sampled soils from 250 spatially referenced locations within a 25-Ha plot where 28,000 trees had been georeferenced, and analyzed spatial patterns of plant and SOM properties. We then examined the extent to which the dominance of AM- versus EM-trees relates to 1) the quality of litter inputs to forest soils and 2) the horizontal and vertical distribution of SOM fractions. We found that leaf litters produced by EM-associated trees were generally of lower quality, having a lower concentration of soluble compounds and higher C:N. Concomitant with this, we observed higher soil C:N under EM trees. Interestingly, this reflected greater N storage in AM-dominated soils rather than greater C storage in EM-dominated soils. These patterns were driven by the storage of SOM in N-rich fractions in AM-dominated soils. Specifically, trees with high litter quality were associated with greater amounts of deep and mineral-associated SOM; pools that are generally considered stable. Our results support the recent contention that high-quality plant inputs should lead to the formation of stable SOM and suggest that the AM-EM framework may provide a way forward for representing litter quality effects on SOM in earth system models.

  11. Chemical characterization of soil organic matter in a Chesapeake Bay salt marsh: analyzing microbial and vegetation inputs to SOM

    Science.gov (United States)

    Bye, E.; Schreiner, K. M.; Abdulla, H. A.; Minor, E. C.; Guntenspergen, G. R.

    2017-12-01

    Coastal wetlands play a critical role in the global carbon cycle. These ecosystems sequester and store carbon, known as "blue carbon," at a rate two or three orders of magnitude larger than other terrestrial ecosystems, such as temperate, tropical, and boreal forests. Anthropogenic changes to the climate are threatening blue carbon stores in coastal wetland ecosystems. To understand and predict how these important carbon stores will be affected by anthropogenic climate changes, it is necessary to understand the formation and preservation of soil organic matter (SOM) in these ecosystems. This study will present organic geochemical data from two sediment cores collected from the Smithsonian Environmental Research Center site on a salt marsh in Maryland along the Chesapeake Bay. One core is from a location that recently transitioned from a C4 to C3 plant regime, currently dominated by the sedge Shoenplectis americanus. The second core is from a C4 plant (Spartina patens) dominated location in the marsh. The organic geochemistry of these 100 cm deep sediment cores was studied through multiple bulk analyses including stable isotopes, elemental ratios, Fourier-transform infrared spectroscopy (FTIR), solid-state magic-angle-spinning Nuclear Magnetic Resonance (NMR), and compound specific lignin-phenol analysis. By using comprehensive chemical characterization techniques, this study aims to discern between vegetation- and microbially-derived inputs to SOM in blue carbon ecosystems. The results show a general increase in the aromatic content with a concomitant decrease of carbohydrates with depth in both cores. However, substantial differences between the two cores, indicates differing inputs and/or stabilization mechanisms within SOM formed from different vegetation regimes. Further compound specific work will help to elucidate the specific source of compounds within each compound class, in surface and deep SOM, and additionally can help provide evidence for different

  12. A more holistic understanding of soil organic matter pools of alpine and pre-alpine grassland soils in a changing climate

    Science.gov (United States)

    Garcia Franco, Noelia; Wiesmeier, Martin; Kiese, Ralf; Dannenmann, Michael; Wolf, Benjamin; Brandhuber, Robert; Beck, Robert; Kögel-Knabner, Ingrid

    2016-04-01

    In southern Germany, the alpine and pre-alpine grassland systems (> 1 Mio ha) provide an important economic value via fodder used for milk and meat production and grassland soils support environmental key functions (C and N storage, water retention, erosion control and biodiversity hot spot). In addition, these grassland soils constitute important regions for tourism and recreation. However, the different land use and management practices in this area introduce changes which are likely to accelerate due to climate change. The newly launched SUPSALPS project within the BonaRes Initiative of the German Ministry for Education and Research is focused on the development and evaluation of innovative grassland management strategies under climate change with an emphasis on soil functions, which are on the one hand environmental sustainable and on the other hand economically viable. Several field experiments of the project will be initialized in order to evaluate grassland soil functioning for a range of current and climate adapted management practices. A multi-factorial design combines ongoing and new plant-soil meso-/macrocosm and field studies at a multitude of existing long-term research sites along an elevation gradient in Bavaria. One of the specific objectives of the project is to improve our knowledge on the sensitivity of specific soil organic matter (SOM) fractions to climate change. Moreover, the project aims to determine the processes and mechanisms involved in the build-up and stabilization of C and N pools under different management practices. In order to derive sensitive SOM pools, a promising physical fractionation method was developed that enables the separation of five different SOM fractions by density, ultrasonication and sieving separation: fine particulate organic matter (fPOM), occluded particulate organic matter (oPOM>20μm and oPOM 20 μm; medium + fine silt and clay, management changes.

  13. Lime and phosphogypsum impacts on soil organic matter pools in a tropical Oxisol under long-term no-till conditions

    Science.gov (United States)

    Improving soil organic matter (SOM) quality in tropical acid soils is important for increasing the sustainability of agricultural ecosystems. This research evaluated the effect of the surface application of lime and phosphogypsum on the quality and amount of SOM in a long-term crop rotation under no...

  14. Mechanistic modelling of the vertical soil organic matter profile

    NARCIS (Netherlands)

    Braakhekke, M.C.

    2014-01-01

    Soil organic matter (SOM) constitutes a large global pool of carbon that may play a considerable role for future climate. The vertical distribution of SOM in the profile may be important due to depth-dependence of physical, chemical, and biological conditions, and links to physical processes

  15. Chemical evaluation of soil organic matter structure in diverse cropping systems

    Science.gov (United States)

    Soil organic matter (SOM) improves soil structure, nutrient and water retention, and biodiversity while reducing susceptibility to soil erosion. SOM also represents an important pool of C that can be increased to help mitigate global climate change. Our understanding of how agricultural management ...

  16. Characterization of extractable soil organic matter pools from African Dark Earths (AfDE): A case study in historical biochar and organic waste amendments

    Science.gov (United States)

    Fujiu, Manna; Plante, Alain; Ohno, Tsutomu; Solomon, Dawit; Lehmann, Johannes; Fraser, James; Leach, Melissa; Fairhead, James

    2014-05-01

    Anthropogenic Dark Earths are soils generated through long-term human inputs of organic and pyrogenic materials. These soils were originally discovered in the Amazon, and have since been found in Australia and in this case in Africa. African Dark Earths (AfDE) are black, highly fertile and carbon-rich soils that were formed from the original highly-weathered infertile yellowish to red Oxisols and Ultisols through an extant but hitherto overlooked climate-smart sustainable soil management system that has long been an important feature of the indigenous West African agricultural repertoire. Studies have demonstrated that ADE soils in general have significantly different organic matter properties compared to adjacent non-DE soils, largely attributable to the presence of high concentrations of ash-derived carbon. Quantification and characterization of bulk soil organic matter of several (n=11) AfDE and non-AfDE pairs of surface (0-15 cm) soils using thermal analysis techniques (TG-DSC-EGA) confirmed substantial differences in SOM composition and the presence of pyrogenic C. Such pyrogenic organic matter is generally considered recalcitrant or relatively stable, but the goal of the current study was to characterize the presumably labile, more rapidly cycling, pools of C in AfDEs through the characterization of hot water- and pyrophosphate-extractable fractions, referred to as HWEOC and PyroC respectively. Extracts were analyzed for carbon content, as well as composition using fluorescence (EEM/PARAFAC) and high resolution mass spectrometry (FTICR-MS). The amount of extractable C as a proportion of total soil C was relatively low: less than ~0.8% for HWEOC and 2.8% for PyroC. The proportion of HWEOC did not differ (P = 0.18, paired t-test) between the AfDE and the non-AfDE soils, while the proportions of PyroC were significantly larger (P = 0.001) in the AfDE soils compared to the non-AfDE soils. Preliminary analysis of the EEM/PARAFAC data suggests that AfDE samples had

  17. Modelling bare fallow SOM dynamics on a Chernozem soil in Central Germany

    Science.gov (United States)

    Franko, Uwe; Merbach, Ines

    2017-04-01

    The level of our process understanding about carbon and nitrogen fluxes in soils becomes visible at extreme situations like bare fallow soils. The observed dynamics of soil organic carbon (SOC) and total nitrogen (TN) in the top soil on a 28 years old fallow experiment on Haplic Chernozem in Bad Lauchstädt (Germany) was modelled using the Candy Carbon Balance (CCB) model that in its standard version was previously validated with LTFE data from Central Europe and a tillage experiment in Austria. For this study we selected two treatments of the fallow experiment in Bad Lauchstädt where the soil was kept bare with mechanical or chemical treatments. For this extreme land use (no input of fresh organic matter) the CCB model was improved to include the SOC related change of soil physical parameters and a dynamic handling of the physically stabilized soil organic matter (SOM) pool. The results from observation and modelling reflected the increased SOM turnover due to soil tillage for carbon as well as nitrogen and thus confirmed the modelling approach for non-tillage in CCB. The added sub model for the dynamics of physically stabilized SOM was also verified. The long term stabilized SOM is very important on this site. The modelled size of the physically stabilized SOC pool was about 55% of total SOC and reduced only slowly during the nearly three decades but the implementation of this effect resulted in improved simulation results. Thus we conclude that scenarios that lead to bigger changes of SOM stocks require a modelling approach that acknowledges the interaction between SOM and soil physical properties.

  18. Mobning som socialt begreb

    DEFF Research Database (Denmark)

    Schott, Robin May

    2009-01-01

    Artiklen analyserer mobning i skolen som et socialt fænomen snarere end som en relation mellem individuelle mobbere og deres ofre. Denne tilgang afspejler nyere forskning, der har fokuseret på mobningens sociale dynamik, og står derved i modsætning til den individualistisk tilgang, der ellers har...... domineret feltet. Jeg undersøger tre definition af mobning: 1) mobning som en form for individuel aggression, 2) mobning som en slags samfundsmæssig vold og 3) mobning som en form for dysfunktionel gruppedynamik og kommer med et forslag til en ny definition....

  19. Molecular characterization of organic matter in converted forests in Western Europe; disentangling the effects of edaphic factors and input differences on SOM composition

    Science.gov (United States)

    Brock, Olaf; Kooijman, Annemieke; Vancampenhout, Karen; Muys, Bart; Jansen, Boris

    2017-04-01

    By storing carbon in the soil, forests can play an important role in climate mitigation. We studied how the SOM composition was affected by conversion of deciduous stands to mono-culture spruce plantations in the Mullerthal in Luxembourg and the Gaume in south-east Belgium. Both regions have a known and similar vegetation history on different lithologies, ranging from carcareous marls to decalcified sands. Lignin and cutin/suberin biomarkers were identified by using thermally assisted hydrolysis and methylation (THM) with unlabelled tetra methyl ammonium hydroxide (TMAH). Lignin was used to distinguish deciduous and coniferous litter sources, whereas cutin and suberin indicated the respective input of above- and belowground litter input. A twinplot setup was used to be able to independently evaluate the effect of edaphic factors versus input differences on SOM composition. pH values and SOC stocks reflected the lithological gradients in both study areas. The difference was more subtle in the Gaume where the gradient is much narrower. The existence of pedogenic thresholds explains why significant differences in lignin yield and SOC stocks between plots with different lithology were also found along the subtle gradient in the Gaume. Secondly, we observed differences in molecular composition and also in decomposition state of lignin that were caused solely by input differences between adjacent deciduous and coniferous forest plots. Furthermore, we found a legacy effect, a signal of former deciduous forest in the deeper soil layers (15-20 cm) under the current spruce plantations, in the loamy substrate plots of the Gaume, which was not observed in the Mullerthal, despite the similar vegetation history of both regions. This can be explained by differences in environmental conditions between both areas. Higher pH values resulting in a higher biological activity could explain the absence of a legacy effect in the Mullerthal plots. Therefore, an important conclusion of

  20. Effect of temperature on the decomposition of labile and recalcitrant organic matter in Chernozem

    Science.gov (United States)

    Larioinova, Alla; Kvitkina, Anna; Bykhovets, Sergey; Stulin, Alexandr; Blagodatskaya, Evgenia

    2017-04-01

    We tested the hypothesis that the recalcitrant pool of soil organic matter (SOM) is more temperature sensitive to decomposition than the labile one. The hypothesis was verified for Chernozem soil sampled from the control (unfertilized) and fertilized with NPK experimental plots of the 50 year field experiment with maize monoculture in Voronezh Region, Russia (51o41'N, 39o15'E). The labile and recalcitrant SOM pools at 2, 12, and 22°C in a long-term (430 d) incubation experiment were traced using the method of 13C natural abundance by C3-C4 transition. Based on decomposition rate constants, the SOM pools followed the order plant residues < new (C4) SOM < old (C3) SOM, with plant residues as the most labile C pool. The hypothesis was valid only for the temperature interval of 12-22°C, where Q10 values increased in the recalcitrance order from 1.2 (plant residues) to 4.3 (C3 SOM). At low temperatures (2-12°C), the values of Q10 varied in the narrow range of 2.2-2.8 irrespective of a SOM pool. In the soil under maize monoculture fertilized with NPK, the increased decomposition of C3 SOM was observed compared to the unfertilized control. The input of new C4 carbon decreased the rate of CO2 emission during the decomposition of the old C3 SOM, i.e. induced negative priming effect (PE). To the contrast, the fertilization increased the positive PE for the C3 SOM. Along with the SOM decomposition rate constants, the magnitude of PE was also temperature dependent. The maximal negative PE in control treatment was found at the lowest temperature of 2oC, while the highest positive PE in NPK fertilized soil was observed at the highest temperature of 22oC.

  1. Modeling soil organic matter (SOM) from satellite data using VISNIR-SWIR spectroscopy and PLS regression with step-down variable selection algorithm: case study of Campos Amazonicos National Park savanna enclave, Brazil

    Science.gov (United States)

    Rosero-Vlasova, O.; Borini Alves, D.; Vlassova, L.; Perez-Cabello, F.; Montorio Lloveria, R.

    2017-10-01

    Deforestation in Amazon basin due, among other factors, to frequent wildfires demands continuous post-fire monitoring of soil and vegetation. Thus, the study posed two objectives: (1) evaluate the capacity of Visible - Near InfraRed - ShortWave InfraRed (VIS-NIR-SWIR) spectroscopy to estimate soil organic matter (SOM) in fire-affected soils, and (2) assess the feasibility of SOM mapping from satellite images. For this purpose, 30 soil samples (surface layer) were collected in 2016 in areas of grass and riparian vegetation of Campos Amazonicos National Park, Brazil, repeatedly affected by wildfires. Standard laboratory procedures were applied to determine SOM. Reflectance spectra of soils were obtained in controlled laboratory conditions using Fieldspec4 spectroradiometer (spectral range 350nm- 2500nm). Measured spectra were resampled to simulate reflectances for Landsat-8, Sentinel-2 and EnMap spectral bands, used as predictors in SOM models developed using Partial Least Squares regression and step-down variable selection algorithm (PLSR-SD). The best fit was achieved with models based on reflectances simulated for EnMap bands (R2=0.93; R2cv=0.82 and NMSE=0.07; NMSEcv=0.19). The model uses only 8 out of 244 predictors (bands) chosen by the step-down variable selection algorithm. The least reliable estimates (R2=0.55 and R2cv=0.40 and NMSE=0.43; NMSEcv=0.60) resulted from Landsat model, while Sentinel-2 model showed R2=0.68 and R2cv=0.63; NMSE=0.31 and NMSEcv=0.38. The results confirm high potential of VIS-NIR-SWIR spectroscopy for SOM estimation. Application of step-down produces sparser and better-fit models. Finally, SOM can be estimated with an acceptable accuracy (NMSE 0.35) from EnMap and Sentinel-2 data enabling mapping and analysis of impacts of repeated wildfires on soils in the study area.

  2. Intelligent design som videnskab?

    DEFF Research Database (Denmark)

    Klausen, Søren Harnow

    2007-01-01

    Diskuterer hvorvidt intelligent design kan betegnes som videnskab; argumenterer for at dette grundet fraværet af klare demarkationskriterier næppe kan afvises.......Diskuterer hvorvidt intelligent design kan betegnes som videnskab; argumenterer for at dette grundet fraværet af klare demarkationskriterier næppe kan afvises....

  3. Gipskroppe som performance

    DEFF Research Database (Denmark)

    Holm, Henrik

    2010-01-01

    Analyse af den Kgl. Afstøbningssamlings nøgne gipsfigurer og samlingens nedtur igennem historien, med Judith Butler og andres performativitetsteorietiske begrebsapparat som metode.......Analyse af den Kgl. Afstøbningssamlings nøgne gipsfigurer og samlingens nedtur igennem historien, med Judith Butler og andres performativitetsteorietiske begrebsapparat som metode....

  4. Yoga som terapeutisk aktivitet

    DEFF Research Database (Denmark)

    Broge, Julie Wolf

    2014-01-01

    Artiklen præsenterer yoga som terapeutisk aktivitet til børn og unge med særlige behov. Den gavnlige virkning af yoga uddybes.......Artiklen præsenterer yoga som terapeutisk aktivitet til børn og unge med særlige behov. Den gavnlige virkning af yoga uddybes....

  5. Leg som ustyrlig deltagelseskultur

    DEFF Research Database (Denmark)

    Toft, Herdis

    2017-01-01

    - og spilteoretikere Johan Huizinga og Roger Caillois. Deres teorier og begrebsdannelser har været brugt til at påpege leg dels som et æstetisk baseret betydningssystem, dels som et affektivt og stemningsbaseret oplevelsessystem samt endelig som et socialt baseret relationssystem. I artiklen vælger vi...... at fokusere på leg som et socialt baseret relationssystem og yderligere zoome ind på et af legens systemiske væsenstræk, nemlig brugen af regulerbare regelsæt, som legerne uden ’politi’ forhandler sig frem til før, under og efter legen. Fælles for Huizinga og Caillois er, at de knytter leg uløseligt sammen...

  6. Supervision som undervisningsform i voksenspecialundervisningen

    DEFF Research Database (Denmark)

    Kristensen, René

    2000-01-01

    Supervision som undervisningsform i voksenspecialundervisningen. Procesarbejde i undervisning af voksne.......Supervision som undervisningsform i voksenspecialundervisningen. Procesarbejde i undervisning af voksne....

  7. Komponist som kirkefader?

    DEFF Research Database (Denmark)

    Petersen, Nils Holger

    2016-01-01

    En diskussion primært af Karl Barths anvendelse Mozart in sin Kirchliche Dogmatik under læren om "das Nichtige", som en slags løsning på theodicé-problemet.......En diskussion primært af Karl Barths anvendelse Mozart in sin Kirchliche Dogmatik under læren om "das Nichtige", som en slags løsning på theodicé-problemet....

  8. Straf som penibel ledelsesform

    DEFF Research Database (Denmark)

    Knudsen, Hanne; Bjerg, Helle

    2014-01-01

    Kan klasseledelse fungere uden muligheden for at straffe? Kan man have en skole uden straf? Hvis man ser tilbage på skolens historie, ser svaret ud til at være nej. Skolen som institution ser ud til at være uløseligt forbundet med disciplinering af eleverne til at gøre noget, som de ikke nødvendi...

  9. Musik som analogi og metafor

    DEFF Research Database (Denmark)

    Bonde, Lars Ole

    2014-01-01

    Indeholder underkapitlerne: 2.5.1 Musik som analogi 2.5.2 Musik som metafor 2.5.3 Musikkens psykologiske funktioner - en taxonomi og metaforisk lytning til fire baroksatser......Indeholder underkapitlerne: 2.5.1 Musik som analogi 2.5.2 Musik som metafor 2.5.3 Musikkens psykologiske funktioner - en taxonomi og metaforisk lytning til fire baroksatser...

  10. Evaluation of the sensitivity of the mineralizable pool of soil organic matter to changes in temperature and moisture

    Science.gov (United States)

    Tulina, A. S.; Semenov, V. M.

    2015-08-01

    The sensitivity of the potentially mineralizable pool of soil organic matter (Cpm) to changes in temperature and moisture has been assessed from the temperature coefficient ( Q10) and the moisture coefficient ( W 10), which indicate how much the Cpm size changes, when the temperature changes by 10°C and the soil water content changes by 10 wt %, respectively. Samples of gray forest soil, podzolized chernozem, and dark chestnut soil taken from arable plots have been incubated at 8, 18, and 28°C and humidity of 10, 25, and 40 wt %. From the data on the production of C-CO2 by soil samples during incubation for 150 days, the content of Cpm has been calculated. It has been shown that, on average for the three soils, an increase in temperature accounts for 63% of the rise in the pool of potentially mineralizable organic matter, whereas an increase in moisture accounts for 8% of that rise. The temperature coefficients of the potentially mineralizable pool are 2.71 ± 0.64, 1.27 ± 0.20, and 1.85 ± 0.30 in ranges of 8-18, 18-28, and 8-28°C, respectively; the moisture coefficients are 1.19 ± 0.11, 1.09 ± 0.05, and 1.14 ± 0.06 in ranges of 10-25, 25-40, and 10-40 wt %, respectively. The easily mineralizable fraction (C1, k 1 > 0.1 days-1) of the active pool of soil organic matter is less sensitive to temperature than the hardly mineralizable fraction (C3, 0.01 > k 3 > 0.001 days-1); their Q 10 values are 0.91 ± 0.15 and 2.40 ± 0.31, respectively. On the contrary, the easily mineralizable fraction is more sensitive to moistening than the hardly mineralizable fraction: their W 10 values are 1.22 ± 0.06 and 1.03 ± 0.08, respectively. The intensification of mineralization with rising temperature and water content during a long-term incubation results in the exhausting of the active pool, which reduces the production of CO2 by the soils during the repeated incubation under similar conditions nonlimiting mineralization.

  11. Distribution and origin of suspended matter and organic carbon pools in the Tana River Basin, Kenya

    NARCIS (Netherlands)

    Tamooh, F.; Van den Meersche, K.; Meysman, F.; Marwick, T.R.; Borges, A.V.; Merckx, R.; Dehairs, F.; Schmidt, S.; Nyunja, J.; Bouillon, S.

    2012-01-01

    We studied patterns in organic carbon pools and their origin in the Tana River Basin (Kenya), in February 2008 (dry season), September–November 2009 (wet season), and June–July 2010 (end of wet season), covering the full continuum from headwater streams to lowland mainstream sites. A consistent

  12. Boken som medium

    OpenAIRE

    Pelle, Snickars

    2012-01-01

    I slutet av september 2011 presenterade Amazon ett ny slags surfplatta, Kindle Fire. Till skillnad från företagets tidigare läsplattor, som (nästan) enbart handlat om läsning på skärm, var detta en Kindle som behärskade hela det samtidsmediala spektrat. Under ledning av Amazons VD Jeff Bezos var själva lanseringen av Kindle Fire visserligen en ganska platt historia. Bezos är ingen estradör och en föga karismatisk företagsledare med än mindre publikreaktioner gör inte någon succé – eller som e...

  13. Micropore characteristics of organic matter pools in cemented and non-cemented podzolic horizons

    NARCIS (Netherlands)

    Catoni, M.; D'amico, M.E.; Mittelmeijer-Hazeleger, M.C.; Rothenberg, G.; Bonifacio, E.

    2014-01-01

    In Podzols, organic matter (OM) is stabilized mainly by interaction with minerals, as a direct consequence of pedogenic processes. Metal-organic associations strongly affect OM surface features, particularly microporosity. Cemented ortstein horizons (CM) may form during podzolization, accompanied by

  14. Gruppeeksamen som strategisk kommunikation

    DEFF Research Database (Denmark)

    Andersen, Tem Frank; Bang, Janne

    2014-01-01

    Artiklen har fokus på at skabe et grundlag for en teoretisk diskussion af gruppeeksamen som den bedste og mest egnede form for eksamen, når problembaseret læring er mål og middel i regi af Aalborg Universitet.......Artiklen har fokus på at skabe et grundlag for en teoretisk diskussion af gruppeeksamen som den bedste og mest egnede form for eksamen, når problembaseret læring er mål og middel i regi af Aalborg Universitet....

  15. Diagnoser som styringshybrider

    DEFF Research Database (Denmark)

    Bossen, Claus; Danholt, Peter; Ubbesen, Morten Bonde

    2016-01-01

    - Relaterede Grupper (DRG). DRG er et internationalt udbredt system til at knytte patienter og deres behandlingsomkostninger sammen i faste kategorier med henblik på at måle hospitalers produktivitet. Med afsæt i Science-Technology-Studies (STS)-feltet analyserer artiklen, hvorledes diagnoser overskrider deres......, hvordan DRG-systemet alternativt kan anskues som en samfundsudviklende infrastruktur, idet det forsamler og skaber gensidigt involverende interaktioner imellem politiske, administrative og sundhedsprofessionelle domæner. En sådan indsigt bidrager til en udvidet forståelse af infrastrukturers roller som...

  16. Lannister som statsminister

    DEFF Research Database (Denmark)

    Konzack, Lars

    2014-01-01

    Der er fuld skrue på intriger, sex og død i Game of Thrones. Det er stærkt underholdende og kan også ses som et billede på de moderne politiske spil. Hvem er seriens Putin? Og hvilken politisk leder ligner Prins Joffrey?......Der er fuld skrue på intriger, sex og død i Game of Thrones. Det er stærkt underholdende og kan også ses som et billede på de moderne politiske spil. Hvem er seriens Putin? Og hvilken politisk leder ligner Prins Joffrey?...

  17. Kollektivet som korrektiv

    DEFF Research Database (Denmark)

    Krøjer, Jo; Hutters, Camilla

    2008-01-01

    I Danmark har de unge individuel valgfrihed, når det kommer til valget af videregående uddannelse. Der er ikke nogen uddannelsespligt - valget er op til den unge. Den etablerede uddannelsesvejledning initierer et selvarbejde, hvorunder de unge anspores til at arbejde individuelt med at træffe det...... rette uddannelsesvalg. De unge oplever uddannelsesvalget som et ensomt og belastende arbejde. Så hvad sker der, når unge kollektivt reflekterer over at skulle vælge uddannelse? Artiklen præsenterer fortælleværksteder som metode til kollektive korrektioner af neoliberal regulering....

  18. Insulin som trickster

    DEFF Research Database (Denmark)

    Lassen, Aske Juul

    2011-01-01

    grænser nedbrydes i en konstant penetrering af huden, når blodsukkeret måles eller insulinen indsprøjtes. Insulin analyseres som en tricksterfigur, der udøver et grænsearbejde på kroppen, leger med dens kategorier og vender forholdet mellem gift og medicin, frihed og ufrihed, kunstighed og naturlighed...

  19. Digitalisering som kulturpolitik

    DEFF Research Database (Denmark)

    Lund, Niels Dichov

    2009-01-01

    Begreberne kulturarv, digitalisering og formidling drøftes generelt som væsentlige nutidsagendaer i lyset af en treeninghed af teknologi, demokrati og kultur. Digital formidling af kulturarv belyses i forhold til en længere dobbbeltsporet forskningskontekst mellem IKT og humaniora og ses primært...

  20. Industrirobotten som servomekanisme

    DEFF Research Database (Denmark)

    Sørensen, Torben

    2001-01-01

    ). Bevægeleddene er typisk enten roterende drejeled, eller lineære forskydningsled. Rotationen eller forskydningen mellem to bevægeled varetages af en servostyret motor. Selve robotarmen er forbundet til robottens base gennem et bevægeled (servoakse) som bærer hele armen - det vil sige alle armens elementer og...

  1. Krisen som udfordring

    DEFF Research Database (Denmark)

    Højrup, Thomas

    2009-01-01

    Om Thorupstrand Kystfiskerlaug, Han Herred Puljefiskeri og Han Herred Havbådes innovative bidrag til en samlet indsats for at sikre kystfiskeriet i Skagerrak fra åben strand som en levende og håndværksbåret kystkultur i Danmark. Den venturekapitalistiske højkonjunktur, regeringens privatiseringsp...

  2. Turistkort som geografisk kommunikation

    DEFF Research Database (Denmark)

    Nielsen, Niels Christian

    2009-01-01

      Kort har længe spillet en central rolle i turisters ferieplanlægning og aktiviteter på feriestedet, og forventes at gøre det i fremtiden, suppleret med andre kilder til geografisk information. Men først i forbindelse med introduktionen af GIS og mobile applikationer som telefon og GPS er den...

  3. Sprog som musikalsk notation

    DEFF Research Database (Denmark)

    Bergstrøm-Nielsen, Carl

    Artiklen behandler sprogbrug som supplement til noderne fra barokken og frem; Fluxus og Scratch Orchestra; den engelske Verbal Anthology; Stockhausens brug af verbal notation før tekst-samlingerne; detaljerede analyser af de to samlinger. Der konkluderes bla. om forskellige grader af fastlæggelse...

  4. Selvskade som selvteknologi

    DEFF Research Database (Denmark)

    Rasmussen, Anna Lanken; Rasmussen, Svend Aage

    2016-01-01

    livshandlinger” – selvskade som social lidelse. Herefter argumenterer forfatterne med udgangspunkt i et feltstudie af Helen Gremillion for vigtigheden af at kaste et kritisk blik på behandlingskultur. Denne kritik videreføres i et afsnit om den postmoderne udfordring i forhold til selvskade. Afslutningsvis...

  5. Som at noget lettede

    DEFF Research Database (Denmark)

    Berliner, Peter; Glendøs, Mia

    2010-01-01

    Den høje voldsrate i Kalaallit Nunaat (Grønland) forklares ofte ud fra alkoholmisbrug og affektive handlinger. I denne artikel vises det gennem en kvantitativ og kvalitativ undersøgelse, at den episodiske vold må forstås som symptomer på strukturel vold. Den strukturelle vold er en kontekst, der ...

  6. Studerende som co-creators

    DEFF Research Database (Denmark)

    Andersen, Line Palle

    En kogebog blev udviklet med studerende som co-creators på 3 moduler om innovation, skriftlig kommunikation og praktik med redigering. Healeys model om student-partnerships blev anvendt som fundament......En kogebog blev udviklet med studerende som co-creators på 3 moduler om innovation, skriftlig kommunikation og praktik med redigering. Healeys model om student-partnerships blev anvendt som fundament...

  7. Kakkelovnen som arkiv

    DEFF Research Database (Denmark)

    Duedahl, Poul

    2005-01-01

    "Folk gjorde såmænd klogt i at gøre som jeg - jeg bruger kakkelovnen som arkiv" gentog tidligere konseilspræsident J.C. Christensen (1856-1930) ofte over for venner og bekendte. Selv destruerede han de fleste af sine breve, mens han var i live, og i mange år troede man, at hans dagbøger blev bræn...... anledning til nogle refleksioner over, hvad man skal stille op med dem; hvad det er, der får folk til at skrive dagbøger og hvad det er, der får folk til at skille sig af med dem igen....

  8. Informatikken som utopi

    Directory of Open Access Journals (Sweden)

    Jørgen Poulsen

    1986-08-01

    Full Text Available Medieforskerne mødte den nye informationsteknologi med be- tydelig skepsis i begyndelsen af 1980érne. Nu synes pendu- let at være i et andet yderpunkt og utopierne omkring in- formatikkens muligheder blomstrer. Denne artikel forsøger at se informationsteknologien i et socialt perspektiv, i forhold til brugen af andre medier, især TV og radio, og ikke som en kraft "i sig selv". Vores behov for at udføre nye kommunikative handlinger vil være afgørende for infor- matikkens succes. Og her véd vi faktisk moget: I analysen af behovene og deres sociale kontekst (som visse informa- tikutopister synes at glemme synes indsigterne fra de sid- ste 20 års positivestiske og kritiske medieforskning at være brugbare.

  9. Fantasy som religion

    DEFF Research Database (Denmark)

    Davidsen, Markus

    2010-01-01

    Artiklen redegør for George Lucas' religionspædagogiske projekt med Star Wars og jediismens brug af Star Wars som religiøs tekst i en fantasybaseret religion. Afslutningsvist gives en række forslag til hvordan man kan anvende Star Wars og jediismen i folkeskolens religionsundervisning.......Artiklen redegør for George Lucas' religionspædagogiske projekt med Star Wars og jediismens brug af Star Wars som religiøs tekst i en fantasybaseret religion. Afslutningsvist gives en række forslag til hvordan man kan anvende Star Wars og jediismen i folkeskolens religionsundervisning....

  10. Artikelskrivning som eksamensform

    Directory of Open Access Journals (Sweden)

    Lars Domino Østergaard

    2013-09-01

    Full Text Available I denne artikel vil vi diskutere, hvordan studerendes arbejde med udformning af en videnskabelig artikel som afsæt for summativ evaluering af undervisningsmoduler, kan bidrage såvel til de studerendes oplevelse af motivation som til oplevelse af, at de gives muligheder for at udvikle konkrete aka­demiske kompetencer. Vi tager udgangspunkt i en række teoretiske over­vejelser, der knytter den summative evaluering til begreber som autentiske rammer, kompetenceudvikling og motivation. Disse overvejelser supplerer vi med resultaterne af en konkret undersøgelse af et pilotforsøg gen­nem­ført ved 2. semester på kandidatuddannelsen i Idræt på Aalborg Uni­versitet. I relation til to kursusmoduler har de studerende udarbejdet en videnskabelig artikel med afsæt i indsamlet empiri. Undersøgelsen viser, at de studerende i altovervejende grad er positive over for artikelskrivning som udgangspunkt for deres evaluering. Undersøgelsen viser videre, at de studerende oplever en følelse af motivation ved bl.a. at arbejde med selv­valgte problemstillinger. Hvorvidt de studerende faktisk udviklede kom­­petencer i forløbet, som de ikke kunne udvikle ved andre evalueringsformer, er fortsat ikke afdækket men vil være et naturligt næste genstandsfelt for undersøgelse.     In this paper we discuss how setting students a scientific paper to write as part of their course module summative assessment may help motivate students and contribute to their academic competencies. We depart from theoretical considerations that connect summative evaluation to concepts of authentic frameworks, competence development and motivation, and instead argue that writing a scientific paper as part of evaluation may be both motivational to students and provide a framework for developing competencies. We supplement these observations by presenting the results from a study conducted in a 2nd semester master programme in sport science at Aalborg University, Denmark

  11. Snehvides Billede som virkelighedsteater

    DEFF Research Database (Denmark)

    Krøgholt, Ida

    2015-01-01

    nyere affektforskning, der er rettet mod kunstens henvendelsesformer og virkninger (bl.a. Massumi og Deleuze), markeres der en interesseforskydning fra følelse til affekt. Det får den konsekvens, at forklaringer på hvordan kunst fungerer og virker ikke søges i tilskuerens følelsesregistreringer men...... affektive henvendelsesform, henter jeg inspiration i aktør-netværks teorien (Latour) og denne teoris materialitets- og tingsbegreb. Den kølige form for virkelighedsteater, som Snehvides Billede repræsenterer, vil ikke vække tilskuerens trang til at gribe ind i virkeligheden. Den vil snarere, via affekt...

  12. Machinima som kreativ praksis

    DEFF Research Database (Denmark)

    Frølunde, Lisbeth

    2014-01-01

    Video: Machinima som Kreativ Praksis. Videoen fortæller om de overordnede temaer i et forskningsprojekt der undersøgte nye former for online multimedie- og filmproduktion og fællesskaber med fokus på 'machinima' animation. Studiet af machinima var en del af et større dansk projekt og et nordisk f...... forskningprojekt om virtuelle verdener og teknologiudvikling, 2010-13. Videoen er præsenteret på Audiovisual Thinking nr. 7 under temaet: Den kreative økonomi....

  13. Linking groundwater dissolved organic matter to sedimentary organic matter from a fluvio-lacustrine aquifer at Jianghan Plain, China by EEM-PARAFAC and hydrochemical analyses.

    Science.gov (United States)

    Huang, Shuang-bing; Wang, Yan-xin; Ma, Teng; Tong, Lei; Wang, Yan-yan; Liu, Chang-rong; Zhao, Long

    2015-10-01

    The sources of dissolved organic matter (DOM) in groundwater are important to groundwater chemistry and quality. This study examined similarities in the nature of DOM and investigated the link between groundwater DOM (GDOM) and sedimentary organic matter (SOM) from a lacustrine-alluvial aquifer at Jianghan Plain. Sediment, groundwater and surface water samples were employed for SOM extraction, optical and/or chemical characterization, and subsequent fluorescence excitation-emission matrix (EEM) and parallel factor analyses (PARAFAC). Spectroscopic properties of bulk DOM pools showed that indices indicative of GDOM (e.g., biological source properties, humification level, aromaticity and molecule mobility) varied within the ranges of those of two extracted end-members of SOM: humic-like materials and microbe-associated materials. The coexistence of PARAFAC compositions and the sustaining internal relationship between GDOM and extracted SOM indicate a similar source. The results from principal component analyses with selected spectroscopic indices showed that GDOM exhibited a transition trend regarding its nature: from refractory high-humification DOM to intermediate humification DOM and then to microbe-associated DOM, with decreasing molecular weight. Correlations of spectroscopic indices with physicochemical parameters of the groundwater suggested that GDOM was released from SOM and was modified by microbial diagenetic processes. The current study demonstrated the associations of GDOM with SOM from a spectroscopic viewpoint and provided new evidence supporting SOM as the source of GDOM. Copyright © 2015 Elsevier B.V. All rights reserved.

  14. Soil carbon dynamics inferred from carbon isotope compositions of soil organic matter and soil respiration

    International Nuclear Information System (INIS)

    Koarashi, Jun; Asano, Tomohiro; Iida, Takao; Moriizumi, Jun

    2004-01-01

    To better understand 14 C cycling in terrestrial ecosystems, 14 C abundances were evaluated for fractionated soil organic matter (SOM) and soil respiration in an urban forest. In 2001 soil profile, Δ 14 C values of litter and bulk SOM increased rapidly from litter surface (62.7 per mille) to uppermost mineral soil layer (244.9 per mille), and then decreased sharply to 6 cm depth of mineral soil (125.0 per mille). Carbon enriched in 14 C by atmospheric nuclear weapons testing had penetrated to at least 16 cm depth of mineral soil. The average Δ 14 C in atmospheric CO 2 was 58.8 per mille in August 2001, suggesting recent carbon input to the topmost litter layer. Although a similar depth distribution was observed for Δ 14 C values of residual SOM after acid hydrolysis, the Δ 14 C values were slightly lower than those in bulk SOM. This indicates input of 'bomb' C into this organic fraction and higher 14 C abundance in acid-soluble SOM. The most of CO 2 may be derived from the microbial decomposition of the acid-soluble, or labile, SOM. Therefore, the labile SOM may become most influential pool for soil carbon cycling. In contrast, carbon in base-insoluble SOM remained considerably low in 14 C abundance at all depths, suggesting no or little incorporation of 'bomb' C to this fraction. Values of Δ 14 C in soil respiration ranged from 91.9 to 146.4 per mille in August 2001, showing a significant contribution from decomposition of SOM fixed over past 2-40 years. These results indicate that the use of bulk SOM as a representative of soil carbon pool would lead to severe misunderstand of the soil C dynamics on decadal and shorter time scales. (author)

  15. Kroppen som monitor

    DEFF Research Database (Denmark)

    Filges, Tine

    2005-01-01

    Tine Filges tager fat i de unges brug og forhold til porno, og har som en central pointe, at unge langt fra er en homogen gruppe. Der er væsentlige forskelle i unges forhold til deres krop. Dette lyder måske banalt og indlysende, men det er en pointe, der ofte glemmes i den offentlige debat om unge...... og deres kroppe. Abstract: Unges kroppe forbindes ofte med risici og farer. Vi lurer farer alle steder, og medierne er fulde af overskrifter: Fedmeepidemier. Unge med åreforkalkning. Druk. Porno. Spiseforstyrrelser. Selvskadende adfærd. I takt med at kroppen monitoreres, er den i stigende grad blevet...... koloniseret af en bekymret hær af forskere, forældre, pædagoger og terapeuter. Vi spørger ængsteligt: Vil de unge lave deres krop om livet igennem? Vil de virkelig have plastik i brysterne? Vil den næste generation tage Viagra som 18-årige? Kan unge indgå i intime relationer, når de er vokset op med porno på...

  16. Deepwater Horizon oil in Gulf of Mexico waters after 2 years: transformation into the dissolved organic matter pool.

    Science.gov (United States)

    Bianchi, Thomas S; Osburn, Christopher; Shields, Michael R; Yvon-Lewis, Shari; Young, Jordan; Guo, Laodong; Zhou, Zhengzhen

    2014-08-19

    Recent work has shown the presence of anomalous dissolved organic matter (DOM), with high optical yields, in deep waters 15 months after the Deepwater Horizon (DWH) oil spill in the Gulf of Mexico (GOM). Here, we continue to use the fluorescence excitation-emission matrix (EEM) technique coupled with parallel factor analysis (PARAFAC) modeling, measurements of bulk organic carbon, dissolved inorganic carbon (DIC), oil indices, and other optical properties to examine the chemical evolution and transformation of oil components derived from the DWH in the water column of the GOM. Seawater samples were collected from the GOM during July 2012, 2 years after the oil spill. This study shows that, while dissolved organic carbon (DOC) values have decreased since just after the DWH spill, they remain higher at some stations than typical deep-water values for the GOM. Moreover, we continue to observe fluorescent DOM components in deep waters, similar to those of degraded oil observed in lab and field experiments, which suggest that oil-related fluorescence signatures, as part of the DOM pool, have persisted for 2 years in the deep waters. This supports the notion that some oil-derived chromophoric dissolved organic matter (CDOM) components could still be identified in deep waters after 2 years of degradation, which is further supported by the lower DIC and partial pressure of carbon dioxide (pCO2) associated with greater amounts of these oil-derived components in deep waters, assuming microbial activity on DOM in the current water masses is only the controlling factor of DIC and pCO2 concentrations.

  17. DUT som didaktisk felt

    DEFF Research Database (Denmark)

    Qvortrup, Ane; Keiding, Tina B.

    2015-01-01

    undervisningsformer. [Abstract in English] The paper presents a systematic categorization of 115 papers published in the Danish Journal for Teaching and Learning in Higher Education. (DUT) from 2006 to 2013. The aim is to explore which didactic topics the journal deals with and how it contributes to the Danish...... the scholarship of teaching and learning. The categorization shows that most of the contributions deal with teaching methods. A subsequent analysis shows that the contributions almost exclusively deal with active and social teaching methods (teaching as experience and teaching as interaction)......(In Danish and English) Artiklen foretager en systematisk kategorisering og analyse af de bidrag, som har været bragt i Dansk Universitetspædagogisk Tidsskrift (DUT) fra 2006-2013. Formålet er at undersøge, hvilke didaktiske temaer tidskriftet har været optaget af og at diskutere mulige...

  18. Auto-fotografi som metode

    DEFF Research Database (Denmark)

    Mogensen, Mette

    2014-01-01

    Artiklen sætter fokus på auto-fotografi som metode i arbejdsmiljøforskningen. Den organisationsæstetiske tilgang, som metoden ofte forbindes med, udfordres med afsæt i en performativ og aktørnetværks-teoretisk position. Gennem en analyse af et enkelt auto-fotografi vises hvordan en artikulation af...

  19. Værk som handling

    DEFF Research Database (Denmark)

    Jalving, Camilla

    , er det stadig kun ved at blive en del af kunsthistoriens metode. Bogen afdækker derfor først begrebets skiftende betydninger fra J.L. Austins sprogfilosofi til Judith Butlers kønsteori og afprøver derefter, hvordan det kan bruges som metode i kunsthistorien og spores som tema i billedkunsten. Det...

  20. Forskere som nano-arkitekter

    DEFF Research Database (Denmark)

    Nielsen, Morten Muhlig; Andersen, Ebbe Sloth

    2009-01-01

    Dna er et fantastisk byggemateriale, som ud fra enkle principper kan samle sig selv til umådeligt komplicerede strukturer. Forskerne udnytter nu disse egenskaber til at lave deres egne, hjemmedesignede dna-strukturer, som kan tænkes anvendt i mange forskellige sammenhænge. Udgivelsesdato: juli...

  1. Filosofisk terapi som social atilpasning

    DEFF Research Database (Denmark)

    Sørensen, Anders Dræby

    Den dominerende psykopatologi forstår psykiske lidelser som udtryk for en patologisk utilpassethed, og psykoterapiens mål bliver normalisering gennem social og psykisk gentilpasning. Eksistentiel fænomenologi forstår lidelsen som etisk vildfarelse i det normale, og terapiens knytter an begreber o...

  2. Kulturen som krænkelsens virkelighed

    DEFF Research Database (Denmark)

    Brock, Steen

    2006-01-01

    En analyse af forholdet mellem natur og kultur i relation til en opfattelse af kultur, som har sin oprindelse i Cicero, og som har sin genklang i moderne tænkere som Goethe, Wittgenstein, Cavell og E. Wolfgang Orth.......En analyse af forholdet mellem natur og kultur i relation til en opfattelse af kultur, som har sin oprindelse i Cicero, og som har sin genklang i moderne tænkere som Goethe, Wittgenstein, Cavell og E. Wolfgang Orth....

  3. Photo-dissolution of flocculent, detrital material in aquatic environments: contributions to the dissolved organic matter pool.

    Science.gov (United States)

    Pisani, Oliva; Yamashita, Youhei; Jaffé, Rudolf

    2011-07-01

    This study shows that light exposure of flocculent material (floc) from the Florida Coastal Everglades (FCE) results in significant dissolved organic matter (DOM) generation through photo-dissolution processes. Floc was collected at two sites along the Shark River Slough (SRS) and irradiated with artificial sunlight. The DOM generated was characterized using elemental analysis and excitation emission matrix fluorescence coupled with parallel factor analysis. To investigate the seasonal variations of DOM photo-generation from floc, this experiment was performed in typical dry (April) and wet (October) seasons for the FCE. Our results show that the dissolved organic carbon (DOC) for samples incubated under dark conditions displayed a relatively small increase, suggesting that microbial processes and/or leaching might be minor processes in comparison to photo-dissolution for the generation of DOM from floc. On the other hand, DOC increased substantially (as much as 259 mgC gC(-1)) for samples exposed to artificial sunlight, indicating the release of DOM through photo-induced alterations of floc. The fluorescence intensity of both humic-like and protein-like components also increased with light exposure. Terrestrial humic-like components were found to be the main contributors (up to 70%) to the chromophoric DOM (CDOM) pool, while protein-like components comprised a relatively small percentage (up to 16%) of the total CDOM. Simultaneously to the generation of DOC, both total dissolved nitrogen and soluble reactive phosphorus also increased substantially during the photo-incubation period. Thus, the photo-dissolution of floc can be an important source of DOM to the FCE environment, with the potential to influence nutrient dynamics in this system. Copyright © 2011 Elsevier Ltd. All rights reserved.

  4. Interaktionsforskning som metode i erhvervsforskningen

    DEFF Research Database (Denmark)

    Goldschmidt, Lars; Elkjær-Larsen, Jens Kr.

    aktionsforskningen er ikke konsolideret som én fælles forskningstradition. Der er derimod udviklet en række forskningsmetodiske tilgange såsom: Aktionsforskning, Action science,Sociologisk fantasi, Bruger/borger involvering i udviklingsprojekter, Dialogforskning, Reflectivepractice, Action learning, Appreciative...... inquiry, Communities of Inquiry in Communities ofpractice, Clinical inquiry (Baskerville 1996). Metoderne er udviklet i relation til det felt eller problemstilling, som forskergrupperne var engagerede i, og kun enkelte er tænkt ind i enerhvervsforskningskontekst. Denne mangfoldighed har ført til, at det...

  5. Soil organic matter status in forest soils - possible indicators for climate change induced site shifts

    Science.gov (United States)

    Koch, Nadine; Thiele-Bruhn, Sören

    2010-05-01

    The quantity and quality of soil organic matter (SOM) and SOM pools and thus the soil properties related to carbon sequestration and water retention are not constant but exhibit considerable variation through changing climate. In total changes in soil fertility and an increase in plant stress are expected. This is relevant for northwest Europe as well and may have economic and social impacts since functions of forests for wood production, groundwater recharge, soil protection and recreation might be affected. The study is done by comparative investigation of selected sites at four watersheds that represent typical forest stands in the region of Luxembourg and South West Germany. The aim is to identify SOM storage and stability in forest soils and its dependence on site properties and interaction with tree stand conditions. According to state of the art fractionation schemes functional C pools in forest soils and their stabilization mechanisms are investigated. In particular, distribution patterns are determined depending on location, tree stand and climatic conditions. Aim is to identify characteristics of SOM stability through fractionation of SOM according to density, particle size and chemical extractability and their subsequent analytical characterization. So far, reasons about the origin, composition and stabilization mechanisms underlying the different SOM pools are not fully understood. Presented are different patterns of distribution of SOM in relation to land use and site conditions, as well as similarities and differences between the different forest soils and results in addition to passive OM pool, which is mainly responsible for long-term stabilization of carbon in soils. These are aligned with selected general' soil properties such as pH, CEC and texture.

  6. Rwanda - eller hvor som helst

    DEFF Research Database (Denmark)

    Sonne, Charlotte Kærgaard; Weis, Rikke Lise

    2010-01-01

    Sundhedspersonalets rolle under konflikter er ofte et springende punkt, ikke mindst fordi intellektuelle og hermed også uddannet sundhedspersonale ikke sjældent er blandt ofrene i konflikten, som vi har set det med eksemplet i Rwanda.......Sundhedspersonalets rolle under konflikter er ofte et springende punkt, ikke mindst fordi intellektuelle og hermed også uddannet sundhedspersonale ikke sjældent er blandt ofrene i konflikten, som vi har set det med eksemplet i Rwanda....

  7. Little effects on soil organic matter chemistry of density fractions after seven years of forest soil warming.

    Science.gov (United States)

    Schnecker, Jörg; Borken, Werner; Schindlbacher, Andreas; Wanek, Wolfgang

    2016-12-01

    Rising temperatures enhance microbial decomposition of soil organic matter (SOM) and thereby increase the soil CO 2 efflux. Elevated decomposition rates might differently affect distinct SOM pools, depending on their stability and accessibility. Soil fractions derived from density fractionation have been suggested to represent SOM pools with different turnover times and stability against microbial decomposition. To investigate the effect of soil warming on functionally different soil organic matter pools, we here investigated the chemical and isotopic composition of bulk soil and three density fractions (free particulate organic matter, fPOM; occluded particulate organic matter, oPOM; and mineral associated organic matter, MaOM) of a C-rich soil from a long-term warming experiment in a spruce forest in the Austrian Alps. At the time of sampling, the soil in this experiment had been warmed during the snow-free period for seven consecutive years. During that time no thermal adaptation of the microbial community could be identified and CO 2 release from the soil continued to be elevated by the warming treatment. Our results, which included organic carbon content, total nitrogen content, δ 13 C, Δ 14 C, δ 15 N and the chemical composition, identified by pyrolysis-GC/MS, showed no significant differences in bulk soil between warming treatment and control. Surprisingly, the differences in the three density fractions were mostly small and the direction of warming induced change was variable with fraction and soil depth. Warming led to reduced N content in topsoil oPOM and subsoil fPOM and to reduced relative abundance of N-bearing compounds in subsoil MaOM. Further, warming increased the δ 13 C of MaOM at both sampling depths, reduced the relative abundance of carbohydrates while it increased the relative abundance of lignins in subsoil oPOM. As the size of the functionally different SOM pools did not significantly change, we assume that the few and small

  8. Beyond clay: Towards an improved set of variables for predicting soil organic matter content

    Science.gov (United States)

    Rasmussen, Craig; Heckman, Katherine; Wieder, William R.; Keiluweit, Marco; Lawrence, Corey R.; Berhe, Asmeret Asefaw; Blankinship, Joseph C.; Crow, Susan E.; Druhan, Jennifer; Hicks Pries, Caitlin E.; Marin-Spiotta, Erika; Plante, Alain F.; Schadel, Christina; Schmiel, Joshua P.; Sierra, Carlos A.; Thompson, Aaron; Wagai, Rota

    2018-01-01

    Improved quantification of the factors controlling soil organic matter (SOM) stabilization at continental to global scales is needed to inform projections of the largest actively cycling terrestrial carbon pool on Earth, and its response to environmental change. Biogeochemical models rely almost exclusively on clay content to modify rates of SOM turnover and fluxes of climate-active CO2 to the atmosphere. Emerging conceptual understanding, however, suggests other soil physicochemical properties may predict SOM stabilization better than clay content. We addressed this discrepancy by synthesizing data from over 5,500 soil profiles spanning continental scale environmental gradients. Here, we demonstrate that other physicochemical parameters are much stronger predictors of SOM content, with clay content having relatively little explanatory power. We show that exchangeable calcium strongly predicted SOM content in water-limited, alkaline soils, whereas with increasing moisture availability and acidity, iron- and aluminum-oxyhydroxides emerged as better predictors, demonstrating that the relative importance of SOM stabilization mechanisms scales with climate and acidity. These results highlight the urgent need to modify biogeochemical models to better reflect the role of soil physicochemical properties in SOM cycling.

  9. Short-term bioavailability of carbon in soil organic matter fractions of different particle sizes and densities in grassland ecosystems.

    Science.gov (United States)

    Breulmann, Marc; Masyutenko, Nina Petrovna; Kogut, Boris Maratovich; Schroll, Reiner; Dörfler, Ulrike; Buscot, François; Schulz, Elke

    2014-11-01

    The quality, stability and availability of organic carbon (OC) in soil organic matter (SOM) can vary widely between differently managed ecosystems. Several approaches have been developed for isolating SOM fractions to examine their ecological roles, but links between the bioavailability of the OC of size-density fractions and soil microbial communities have not been previously explored. Thus, in the presented laboratory study we investigated the potential bioavailability of OC and the structure of associated microbial communities in different particle-size and density fractions of SOM. For this we used samples from four grassland ecosystems with contrasting management intensity regimes and two soil types: a Haplic Cambisol and a typical Chernozem. A combined size-density fractionation protocol was applied to separate clay-associated SOM fractions (CF1, <1 μm; CF2, 1-2 μm) from light SOM fractions (LF1, <1.8 g cm(-3); LF2, 1.8-2.0 g cm(-3)). These fractions were used as carbon sources in a respiration experiment to determine their potential bioavailability. Measured CO2-release was used as an index of substrate accessibility and linked to the soil microbial community structure, as determined by phospholipid fatty acids (PLFA) analysis. Several key factors controlling decomposition processes, and thus the potential bioavailability of OC, were identified: management intensity and the plant community composition of the grasslands (both of which affect the chemical composition and turnover of OC) and specific properties of individual SOM fractions. The PLFA patterns highlighted differences in the composition of microbial communities associated with the examined grasslands, and SOM fractions, providing the first broad insights into their active microbial communities. From observed interactions between abiotic and biotic factors affecting the decomposition of SOM fractions we demonstrate that increasing management intensity could enhance the potential bioavailability of

  10. Soil Organic Matter Stability and Soil Carbon Storage with Changes in Land Use Intensity in Uganda

    Science.gov (United States)

    Tiemann, L. K.; Grandy, S.; Hartter, J.

    2014-12-01

    As the foundation of soil fertility, soil organic matter (SOM) formation and break-down is a critical factor of agroecosystem sustainability. In tropical systems where soils are quickly weathered, the link between SOM and soil fertility is particularly strong; however, the mechanisms controlling the stabilization and destabilization of SOM are not well characterized in tropical soils. In western Uganda, we collected soil samples under different levels of land use intensity including maize fields, banana plantations and inside an un-cultivated native tropical forest, Kibale National Park (KNP). To better understand the link between land use intensity and SOM stability we measured total soil C and N, and respiration rates during a 369 d soil incubation. In addition, we separated soils into particle size fractions, and mineral adsorbed SOM in the silt (2-50 μm ) and clay (fractions was dissociated, purified and chemically characterized via pyrolysis-GC/MS. Cultivated soil C and N have declined by 22 and 48%, respectively, in comparison to uncultivated KNP soils. Incubation data indicate that over the last decade, relatively accessible and labile soil organic carbon (SOC) pools have been depleted by 55-59% in cultivated soils. As a result of this depletion, the chemical composition of SOM has been altered such that clay and silt associated SOM differed significantly between agricultural fields and KNP. In particular, nitrogen containing compounds were in lower abundance in agricultural compared to KNP soils. This suggests that N depletion due to agriculture has advanced to pools of mineral associated organic N that are typically protected from break-down. In areas where land use intensity is relatively greater, increases in polysaccharides and lipids in maize fields compared to KNP indicate increases in microbial residues and decomposition by-products as microbes mine SOM for organic N. Chemical characterization of post-incubation SOM will help us better understand

  11. Queer eller manden som ideal

    DEFF Research Database (Denmark)

    Sjørup, Karen

    2016-01-01

    Forestillingen om barnet som den i kønslig forstand renvaskede tavle er fejlagtig og selvmodsigende. I stedet bør forældre og samfund give børn ballast til at begive sig ud i livet uden for mange normative direktiver.......Forestillingen om barnet som den i kønslig forstand renvaskede tavle er fejlagtig og selvmodsigende. I stedet bør forældre og samfund give børn ballast til at begive sig ud i livet uden for mange normative direktiver....

  12. Krisekommunikation som model for virksomhedsretorik?

    DEFF Research Database (Denmark)

    Rasmussen, Rasmus Kjærgaard

    2017-01-01

    kommunikativt konstitueret fænomener. Her argumenterer jeg for en analytisk syntese mellem framingteorier og det såkaldte CCO-paradigme, til sammen kan hjælpe krisekommunikationsteorierne med at slippe den aprioriske tilgang til kriser ved at forstå såvel kriser og organisationer som resultatet af kommunikative...

  13. Medborgerskab som skolefag i Malaysia

    DEFF Research Database (Denmark)

    Tiemensma, Britt Due; Hald, Anne Mette

    2009-01-01

    Globalisering og internationalisering indgår med selvfølgelighed i uddannelsessektorens begrebsverden. Men hvad mener vi egentlig, når vi bruger begreberne? Benyttes de som abstrakte talemåder, for at vi skal kunne forholde os til uoverskueligheden i den aktuelle udvikling, eller kan begreberne k...

  14. Interaktiv forskning som samarbejdsdrevet innovation

    DEFF Research Database (Denmark)

    Martinez, Laia

    2012-01-01

    Hovedformålet med denne artikel er at formidle nogle af de metodiske overvejelser, som jeg har gjort mig om samspillet mellem forskere og praktikere i forbindelse med gennemførelsen af mit Ph.d.-projekt om innovationsledelse i danske kommuner....

  15. Kina som stormagt i Arktis

    DEFF Research Database (Denmark)

    Nørup Sørensen, Camilla Tenna

    I slutningen af januar 2018 offentliggjorde Kina sin længe ventede Arktisstrategi. Den står som en foreløbig kulmination på de senere års udvikling af et mere selvsikkert, proaktivt og sofistikeret kinesisk diplomati i Arktis. Beijing har intensiveret bestræbelserne på at etablere stærke og...

  16. Med det sociale som designmateriale

    DEFF Research Database (Denmark)

    Brandt, Eva; Binder, Thomas

    2016-01-01

    Samarbejde, samskabelse og social nysgerrighed er i dag en præmis for den nyskabende designer. Det sociale er det nye designmateriale som unge designere giver sig i kast med når f.eks. Emmy Linde samarbejder med plejehjemsbeboere, deres pårørende, plejepersonale og fysioterapeuter for at designe ...

  17. Fokusgruppeinterview som led i en evalueringsproces

    DEFF Research Database (Denmark)

    Andersen-Mølgaard, Hanna; Harrit, Ole

    2006-01-01

    Teoretiske begrundelser og perspektiver, responsiv-konstruktivistisk evaluering, fokusgruppeinterview som led i BIKVAmodellen, eksempler, vurdering og perspektivering......Teoretiske begrundelser og perspektiver, responsiv-konstruktivistisk evaluering, fokusgruppeinterview som led i BIKVAmodellen, eksempler, vurdering og perspektivering...

  18. Pools and fluxes of organic matter in a boreal landscape: implications for a safety assessment of a repository for nuclear waste.

    Science.gov (United States)

    Kumblad, Linda; Söderbäck, Björn; Löfgren, Anders; Lindborg, Tobias; Wijnbladh, Erik; Kautsky, Ulrik

    2006-12-01

    To provide information necessary for a license application for a deep repository for spent nuclear fuel, the Swedish Nuclear Fuel and Waste Management Co is carrying out site investigations, including extensive studies of different parts of the surface ecosystems, at two sites in Sweden. Here we use the output from detailed modeling of the carbon dynamics in the terrestrial, limnic and marine ecosystems to describe and compare major pools and fluxes of organic matter in the Simpevarp area, situated on the southeast coast of Sweden. In this study, organic carbon is used as a proxy for radionuclides incorporated into organic matter. The results show that the largest incorporation of carbon into living tissue occurs in terrestrial catchments. Carbon is accumulated in soil or sediments in all ecosystems, but the carbon pool reaches the highest values in shallow near-land marine basins. The marine basins, especially the outer basins, are dominated by large horizontal water fluxes that transport carbon and any associated contaminants into the Baltic Sea. The results suggest that the near-land shallow marine basins have to be regarded as focal points for accumulation of radionuclides in the Simpevarp area, as they receive a comparatively large amount of carbon as discharge from terrestrial catchments, having a high NPP and a high detrital accumulation in sediments. These focal points may constitute a potential risk for exposure to humans in a future landscape as, due to post-glacial land uplift, previous accumulation bottoms are likely to be used for future agricultural purposes.

  19. Methodological Aspects of In Vitro Assessment of Bio-accessible Risk Element Pool in Urban Particulate Matter

    Czech Academy of Sciences Publication Activity Database

    Sysalová, J.; Száková, J.; Tremlová, J.; Kašparovská, Kateřina; Kotlík, B.; Tlustoš, P.; Svoboda, Petr

    2014-01-01

    Roč. 161, č. 2 (2014), s. 216-222 ISSN 0163-4984 Grant - others:GA ČR(CZ) GA521/09/1150; GA ČR(CZ) GAP503/12/0682 Program:GA; GA Institutional support: RVO:67985823 Keywords : risk elements * urban particulate matter * in vitro tests * bio-accessibility Subject RIV: CB - Analytical Chemistry, Separation Impact factor: 1.748, year: 2014

  20. Characterization of Soil Organic Matter from African Dark Earth (AfDE) Soils

    Science.gov (United States)

    Plante, A. F.; Fujiu, M.; Ohno, T.; Solomon, D.; Lehmann, J.; Fraser, J. A.; Leach, M.; Fairhead, J.

    2014-12-01

    Anthropogenic Dark Earths are soils generated through long-term human inputs of organic and pyrogenic materials. These soils were originally discovered in the Amazon, and have since been found in Australia and in this case in Africa. While tropical soils are typically characterized by low soil organic matter (SOM) concentrations, African Dark Earths (AfDE) are black, highly fertile and carbon-rich soils formed through an extant but ancient soil management system. The objective of this study was to characterize the organic matter accumulated in AfDE and contrast it with non-AfDE soils. Characterization of bulk soil organic matter of several (n=11) AfDE and non-AfDE pairs of surface (0-15 cm) soils using thermal analysis techniques (TG-DSC-EGA) resulted in substantial differences in SOM composition and the presence of pyrogenic C. Such pyrogenic organic matter is generally considered recalcitrant, but the fertility gains in AfDE are generated by labile, more rapidly cycling pools of SOM. As a result, we characterized hot water- and pyrophosphate-extractable pools of SOM using fluorescence (EEM/PARAFAC) and high resolution mass spectrometry (FT-ICR-MS). EEM/PARAFAC data suggests that AfDE samples had a greater fraction of their DOM that was more humic-like than the paired non-AfDE samples. Similarly, FT-ICR-MS analyses of extracts suggest that differences among the sites analyzed were larger than between the paired AfDE and non-AfDE extracts. Overall, in spite of substantial differences in the composition of bulk SOM, the extractable fractions appear to be relatively similar between the AfDE and non-AfDE soils.

  1. Cash pooling

    OpenAIRE

    Lozovaya, Karina

    2009-01-01

    This work makes a mention of cash management. At next chapter describes two most known theoretical models of cash management -- Baumol Model and Miller-Orr Model. Principal part of work is about cash pooling, types of cash pooling, cash pooling at Czech Republic and influence of cash pooling over accounting and taxes.

  2. E-tiviteter som eksamensform

    Directory of Open Access Journals (Sweden)

    Anette Grønning

    2011-12-01

    Full Text Available Med udgangspunkt i faget "Digital kommunikation på arbejde" præsenterer og diskuterer denne artikel en række anvendte digitale eksamensformer (e-tiviteter. E-tiviteterne er udarbejdet på baggrund af Gilly Salmons 5-fase-model og e-tivitetskoncept. Den anvendte e-læringsplatform er Blackboard, som de studerende og underviseren kender i forvejen. I artiklen præsenteres fagets e-tiviteter og undervisningsforløbet med e-tiviteter som eksamensform diskuteres. En række fordele og ulemper ved at veksle mellem offline- og online-aktiviteter (blended learning bliver behandlet. Det konkluderes, at de studerendes engagement og motivation kan øges ved at koble e-tiviteter sammen med eksamensformen "80% tilstedeværelse og aktiv deltagelse". Desuden fremhæves det, at aktivitetsniveauet mellem lektionerne og forberedelsesomfaget øges, ligesom de studerende motiveres til higher order thinking ved fx at tage ansvar for egen læring, udføre analyse og indgå i processen med kritisk refleksion. Endelig muliggør online-forløbet, at hele processen dokumenteres i faget til gavn for både underviser og studerende.

  3. Mineral-associated organic matter: are we now on the right path to accurately measuring and modelling it?

    Science.gov (United States)

    Cotrufo, M. F.

    2017-12-01

    Mineral-associated organic matter (MAOM) is the largest and most persistent pool of carbon in soil. Understanding and correctly modeling its dynamic is key to suggest management practices that can augment soil carbon storage for climate change mitigation, as well as increase soil organic matter (SOM) stocks to support soil health on the long-term. In the Microbial Efficiency Mineral Stabilization (MEMS) framework we proposed that, contrary to what originally thought, this form of persistent SOM is derived from the labile components of plant inputs, through their efficient microbial processing. I will present results from several experiments using dual isotope labeling of plant inputs that largely confirm this opinion, and point to the key role of dissolved organic matter in MAOM formation, and to the dynamic nature of the outer layer of MAOM. I will also show how we are incorporating this understanding in a new SOM model, which uses physically defined measurable pools rather than turnover-defined pools to forecast C cycling in soil.

  4. Exciting Pools

    Science.gov (United States)

    Wright, Bradford L.

    1975-01-01

    Advocates the creation of swimming pool oscillations as part of a general investigation of mechanical oscillations. Presents the equations, procedure for deriving the slosh modes, and methods of period estimation for exciting swimming pool oscillations. (GS)

  5. Evaluering som kvalitetsstøtte og mål som guide

    DEFF Research Database (Denmark)

    Levinsen, Karin Tweddell; Sørensen, Birgitte Holm

    2017-01-01

    Dette kapitel omhandler sammenhængen mellem det didaktiske design og evalueringspraksisser som aktivite der understøtter elevernes læring både som proces og produkt. Først gøres der rede for de anvendte begreber, og der argumenteres for, at formative og summative evalueringer kan forstås som...

  6. Assessment of soil organic matter persistence under different land uses applying a physical fractionation procedure

    Science.gov (United States)

    Giannetta, Beatrice; Plaza, César; López-de-Sá, Esther G.; Vischetti, Costantino; Zaccone, Claudio

    2017-04-01

    The understanding of the mechanisms involved in the build-up of soil organic matter (SOM) pools with long residence time is tightly linked to the comprehension of C dynamics. Organo-mineral associations are known to be strongly correlated with the accumulation of selective preserved C forms. Adsorption to minerals, as well as occlusion within aggregates, may affect SOM protection in different ways depending on its molecular structure and pedo-climatic conditions. In this research, we investigated changes in quantity and quality of SOM pools characterized by different protection mechanisms in coniferous and broadleaved forest soils, grassland soils, technosols and an agricultural soil with different organic amendments, in order to evaluate the influence of both land use and organic matter nature on physical and/or chemical stabilization of SOM. In particular, free (FR), intra-macroaggregate (MA), intra-microaggregate (MI), and mineral-associated (Min) fractions were separated in order to define physical and chemical mechanisms responsible for the SOM protection against degradation. All these SOM fractions were analyzed for organic C and total N concentration, and their stability assessed by thermogravimetric analysis (TD-TGA). Preliminary data show that, for all land uses, most of the organic C (40-60%) is found in the Min pool, followed by FR (20-40%)>MI MA. With the only exception of the FR, no significant correlations were found between the C/N ratio and a thermal stability index (H550-400/400-250) of each fraction; at the same time, a highly significant and positive correlation was found between these two parameters in all fractions isolated from agricultural soils. In particular, the thermal stability index measured in all Min fractions may be related to the more marked presence of labile compounds in this pool relative to recalcitrant compounds. Conversely, FR OM could not always represent a fresh and readily decomposable fraction.Furthermore, OM associated

  7. Introduktionslæger som vejledere - hvorfor?

    DEFF Research Database (Denmark)

    Skaarup, Anne Marie; Ringsted, Charlotte Vibeke

    2004-01-01

    Statusartiklen har til hensigt at beskrive det pædagogiske rationale for at anvende introduktionslæger som vejledere, holdningen blandt introduktionslæger og speciallæger til at bruge introduktionslæger som vejledere, og hvilke ulemper der kan identificeres, og hvordan de eventuelt kan overvindes...

  8. Tavs viden som led i vidensdiskursen

    DEFF Research Database (Denmark)

    Christensen, Jens

    2004-01-01

    Bidraget giver en  erkendelsesteoretisk tilgang til tavs viden som ressource i en teknologisk forandringsproces. Der tages udgangspunkt i, at tavs viden ikke kan betragtes uden at forholde sig til den mere generelle og historiske vidensdiskurs, som igen indgår i en kontekst af relationer mellem e...

  9. Sociale medier som læringsredskaber

    Directory of Open Access Journals (Sweden)

    Lill Ingstad

    2011-03-01

    Full Text Available Kan sociale medier anvendes som læringsredskaber til støtte for sociale, kollaborative processer, der er udfordrende og motiverende, og som samtidig understøtter (fremmedsprogstilegnelsen?Artiklen diskuterer eksempler på fagdidaktiske udfordringer i sprogundervisningen på CBS med fokus på engelsk.

  10. Molecular characterization of charcoal to identify adsorbed SOM and assess the effectiveness of common SOM-removing pretreatments prior to radiocarbon dating

    NARCIS (Netherlands)

    Wagner, T.V.; Mouter, A.K.; Parsons, J.R.; Sevink, J.; van der Plicht, J.; Jansen, B.

    A significant part of our knowledge on Holocene landscape development and associated human history in northwestern Europe is based on radiocarbon dating of charcoal originating from podzols. However, these soils are characterized by leaching of soil organic matter (SOM) that may adsorb to older

  11. Organic matter of subsoil horizons under broadleaved forest: Highly processed or labile and plant-derived?

    NARCIS (Netherlands)

    Vancampenhout, K.; Vos, de B.; Wouters, K.; Swennen, R.; Buurman, P.

    2012-01-01

    Between 30 and 63% of the soil organic matter (SOM) is stored below 30 cm, making subsoil-SOM an important source and sink in the global carbon cycle. Nevertheless, detailed information on the composition of subsoil-SOM remains scarce. This study aims to evaluate the chemical composition of SOM in

  12. The regulation by phenolic compounds of soil organic matter dynamics under a changing environment.

    Science.gov (United States)

    Min, Kyungjin; Freeman, Chris; Kang, Hojeong; Choi, Sung-Uk

    2015-01-01

    Phenolics are the most abundant plant metabolites and are believed to decompose slowly in soils compared to other soil organic matter (SOM). Thus, they have often been considered as a slow carbon (C) pool in soil dynamics models. Here, however, we review changes in our concept about the turnover rate of phenolics and quantification of different types of phenolics in soils. Also, we synthesize current research on the degradation of phenolics and their regulatory effects on decomposition. Environmental changes, such as elevated CO2, warming, nitrogen (N) deposition, and drought, could influence the production and form of phenolics, leading to a change in SOM dynamics, and thus we also review the fate of phenolics under environmental disturbances. Finally, we propose the use of phenolics as a tool to control rates of SOM decomposition to stabilize organic carbon in ecosystems. Further studies to clarify the role of phenolics in SOM dynamics should include improving quantification methods, elucidating the relationship between phenolics and soil microorganisms, and determining the interactive effects of combinations of environmental changes on the phenolics production and degradation and subsequent impact on SOM processing.

  13. Long term repeated prescribed burning increases evenness in the basidiomycete laccase gene pool in forest soils.

    Science.gov (United States)

    Artz, Rebekka R E; Reid, Eileen; Anderson, Ian C; Campbell, Colin D; Cairney, John W G

    2009-03-01

    Repeated prescribed burning alters the biologically labile fraction of nutrients and carbon of soil organic matter (SOM). Using a long-term (30 years) repeated burning experiment where burning has been carried out at a 2- or 4-year frequency, we analysed the effect of prescribed burning on gross potential C turnover rates and phenol oxidase activity in relation to shifts in SOM composition as observed using Fourier-transform infrared spectroscopy. In tandem, we assessed the genetic diversity of basidiomycete laccases. While the overall effect of burning was a decline in phenol oxidase activity, Shannon diversity and evenness of laccases was significantly higher in burned sites. Co-correspondence analysis of SOM composition and laccase operational taxonomic unit frequency data also suggested a strong correlation. While this correlation could indicate that the observed increase in laccase genetic diversity due to burning is due to increased resource diversity, a temporal replacement of the most abundant members of the assembly by an otherwise dormant pool of fungi cannot be excluded. As such, our results fit the intermediate disturbance hypothesis. Effects were stronger in plots burned in 2-year rotations, suggesting that the 4-year burn frequency may be a more sustainable practice to ensure the long-term stability of C cycling in such ecosystems.

  14. Liquid sodium pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Casselman, C [DSN/SESTR, Centre de Cadarache, Saint-Paul-lez-Durance (France)

    1979-03-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  15. Liquid sodium pool fires

    International Nuclear Information System (INIS)

    Casselman, C.

    1979-01-01

    Experimental sodium pool combustion results have led to a definition of the combustion kinetics, and have revealed the hazards of sodium-concrete contact reactions and the possible ignition of organic matter (paint) by hydration of sodium peroxide aerosols. Analysis of these test results shows that the controlling mechanism is sodium evaporation diffusion. (author)

  16. Livsstil som tv-underholdning

    Directory of Open Access Journals (Sweden)

    Christa Lykke Christensen

    2008-09-01

    Full Text Available Livsstilsprogrammer har siden slutningen af 1990’erne domineret programfladen i den tidlige prime time på de danske public service-kanaler DR og TV 2. Dermed er emner, som figurerer i bl.a. magasiner og ugeblade, massivt rykket ind på tv’s sendeflade. Bolig, have, mad, ferie, krop og sundhed er indholdet i programmer, der både vil informere, give gode råd og underholde seerne. Artiklen fokuserer på underholdningsdimensionen i tre kategorier af livsstilsprogrammer og undersøger elementer, der kan tænkes at fremme motivationen for at se dem. Her lægges vægten på hhv. vidensperspektivets kompetenceaspekt og livsstilsbegrebets imaginative muligheder i relation til drømmen om ’det gode liv’ og ønsket om den forjættende forandring. Artiklen diskuterer endvidere, hvorledes public service-fjernsynet med disse livsstilsprogrammer har suppleret dets oplysende funktion med en opdaterende funktion, og hvordan dets tidligere kulturelt dannende funktion i kraft af disse programmers karakter af manual kan opfattes som en slags livsstilsguide i forhold til markedets forbrugsmuligheder. Lifestyle as TV entertainment Since the late 1990s lifestyle programmes have dominated early prime time on the Danish public service channels, DR and TV 2. For this reason topics that have traditionally figured in magazines extensively have entered television programming. House, garden, vacation, body, and health form the content of programmes which aim to both inform, advise and entertain viewers. The article primarily focuses on the aspects of entertainment in three main lifestyle categories and is concerned with elements that might promote viewers’ motivation for watching such programmes. Importance is attached to the competence aspect of knowledge and to the imaginative possibilities connected to the idea of lifestyle, related to daydreams, ideas of ‘the good life’, and a desire for promising change. Furthermore, the article discusses how public

  17. Livsstil som tv-underholdning

    Directory of Open Access Journals (Sweden)

    Christa Lykke Christensen

    2008-12-01

    Full Text Available Livsstilsprogrammer har siden slutningen af 1990’erne domineret programfladen i den tidlige prime time på de danske public service-kanaler DR og TV 2. Dermed er emner, som figurerer i bl.a. magasiner og ugeblade, massivt rykket ind på tv’s sendeflade. Bolig, have, mad, ferie, krop og sundhed er indholdet i programmer, der både vil informere, give gode råd og underholde seerne. Artiklen fokuserer på underholdningsdimensionen i tre kategorier af livsstilsprogrammer og undersøger elementer, der kan tænkes at fremme motivationen for at se dem. Her lægges vægten på hhv. vidensperspektivets kompetenceaspekt og livsstilsbegrebets imaginative muligheder i relation til drømmen om ’det gode liv’ og ønsket om den forjættende forandring. Artiklen diskuterer endvidere, hvorledes public service-fjernsynet med disse livsstilsprogrammer har suppleret dets oplysende funktion med en opdaterende funktion, og hvordan dets tidligere kulturelt dannende funktion i kraft af disse programmers karakter af manual kan opfattes som en slags livsstilsguide i forhold til markedets forbrugsmuligheder. Lifestyle as TV entertainment Since the late 1990s lifestyle programmes have dominated early prime time on the Danish public service channels, DR and TV 2. For this reason topics that have traditionally figured in magazines extensively have entered television programming. House, garden, vacation, body, and health form the content of programmes which aim to both inform, advise and entertain viewers. The article primarily focuses on the aspects of entertainment in three main lifestyle categories and is concerned with elements that might promote viewers’ motivation for watching such programmes. Importance is attached to the competence aspect of knowledge and to the imaginative possibilities connected to the idea of lifestyle, related to daydreams, ideas of ‘the good life’, and a desire for promising change. Furthermore, the article discusses how public

  18. From solid to liquid: assessing the release of organic matter into soil solution in response to land-use conversion in Brazilian Oxisols

    Science.gov (United States)

    James, Jason; Gross, Cole; Dwivedi, Pranjal; Bernardi, Rodolpho; Guerrini, Irae; Harrison, Rob; Butman, David

    2017-04-01

    Recent advances in freshwater research indicate that roughly double the quantity of carbon is exported from soils to streams and rivers than was previously estimated, and that the age of carbon exported from major rivers globally increases with greater human disturbance in the watershed. This implies that human land-use can release old, previously mineral-associated C into solution with subsequent export to groundwater and ultimately freshwater systems where terrestrial organic matter is either mineralized to CO2, stored in aquatic sediments, or exported to the ocean. Consequently, it is important to understand the mechanisms that cause the release of SOM that is mineral-bound into solution in response to human disturbance and land-use change. Research methods have been established to examine both the fast turnover, dissolved pool of soil organic matter (SOM), as well as the slow turnover, mineral-associated pool. However, to better characterize the response of the total SOM pool to disturbance, it is necessary to understand the interactions between these functional pools by examining them both simultaneously. This study seeks to examine the interaction between dissolved organic matter (DOM) and bulk SOM throughout the soil profile in response to conversion of Brazilian Cerrado (savannah forest) to Eucalyptus plantation forest on the same soil type. The water-extractable organic matter was obtained from soil samples down to 150 cm, characterized using fluorescence and NMR spectroscopy, and carbon-dated. Simultaneously, bulk mineral soil samples were analyzed for microbial biomass, carbon content and age, and characterized using Fourier Transform Infrared Spectroscopy. SOM spectra were obtained by washing subsamples with sodium hypochlorite and subtracting the subsequent mineral matrix spectra from bulk soil spectra. Preliminary results show that microbial biomass decreases much more quickly with depth than DOM, suggesting that C released into solution from deeper

  19. Some Learning Properties of Modular Network SOMs

    Science.gov (United States)

    Takeda, Manabu; Ikeda, Kazushi; Furukawa, Tetsuo

    The Modular Network Self-Organizing Map (mnSOM) is a generalization of the SOM, where each node represents a parametric function such as a multi-layer perceptron or another SOM. Since given datasets are, in general, fewer than nodes, some nodes never win in competition and have to update their parameters from the winners in the neighborhood. This is a process that can be regarded as interpolation. This study derives the interpolation curve between winners in simple cases and discusses the distribution of winners based on the neighborhood function.

  20. "Hvem er som jeg blandt Guder?"

    DEFF Research Database (Denmark)

    Holst, Søren

    2004-01-01

    En hymne fra Dødehavsrullerne beskriver en persons opstigning til himlen, hvor den pågældende får tildelt overmenneskelig indsigt, som giver ham autoritet til at belære sine tilhængere på jorden. Hymnen analyseres, og der foretages en kritisk gennemgang af Israel Knohls bog "The Messiah Before Je...... Jesus", som hævder at teksten skulle handle om et medlem af Qumran-menigheden, som blev dræbt i Jerusalem og senere hævdedes at være opstået fra de døde....

  1. Videokameraet som etnografisk redskab online og offline

    DEFF Research Database (Denmark)

    Rehder, Mads Middelboe

    2013-01-01

    “Med udgangspunkt i et visuelt feltarbejde såvel online som offline, på YouTube og i New York City, beskæftiger dette kapitel sig med kameraet som medieringsteknologi, med fokus på levende billeder. Det diskuteres, hvordan kameraets multiple anvendelsesmuligheder empirisk og metodisk kan skabe...... forskellige muligheder og begrænsninger i et feltarbejde, samt hvordan det visuelle materiale kan variere som resultat af disse forskellige anvendelser. Den indledende del af kapitlet består af en beskrivelse af det empiriske felt online på YouTube, og det diskuteres, hvordan et online felt relaterer sig til...

  2. Nitrogen Alters Initial Growth, Fine-Root Biomass and Soil Organic Matter Properties of a Eucalyptus dunnii Maiden Plantation in a Recently Afforested Grassland in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Gabriel W. D. Ferreira

    2018-01-01

    Full Text Available Nitrogen (N fertilization effects on Eucalyptus growth and soil carbon (C stocks are still controversial. We set up an N fertilization experiment in southern Brazil to evaluate initial tree growth and changes in soil organic matter (SOM. Four N levels (24–Reference, 36, 48 and 108 kg ha−1 of N were tested and tree growth was assessed during the first two years. Afterwards, representative trees were chosen to evaluate fine-root biomass (FRB and its spatial distribution. Soil was sampled to a 40-cm depth and SOM was fractionated in Particulate (POM and Mineral-Associated Organic Matter (MAOM for C and N content, and δ13C determination. Positive N effect on tree growth was seen only for tree height. N addition resulted in higher FRB. Changes in SOM were more expressive in top-soil layers. Overall, afforestation had positive effects on soil C. Increasing reference N dose resulted in higher C and N content in both SOM fractions. C and N dynamics were tightly correlated, especially in MAOM. Eucalypt-derived C was on average three-fold higher in POM. In summary, we showed that N fertilization may have positive but limited effects on tree growth, nevertheless it enhances fine-root biomass and C and N accumulation in SOM pools.

  3. CEMSKUM - Anvendelighed som isoleringsmateriale i bygninger

    DEFF Research Database (Denmark)

    Hansen, Ernst Jan de Place

    2002-01-01

    Resume af rapport om mulighederne for at anvende Cemskum som isoleringsmateriale i bygningskonstruktioner, udarbejdet af Cemsystems I/S under Energistyrelsens udviklingsprogram "Miljø- og arbejdsmiljøvenlig isolering"...

  4. Byen som bevægelsesgrund?

    DEFF Research Database (Denmark)

    Højbjerre Larsen, Signe

    2013-01-01

    Parkour er en bevægelseskultur der ikke udfolder sig i afgrænsede rum eller på bestemte tidspunkter. Den er i stedet betinget af at byens rum anvendes som bevægelsesgrund. Parkourudøvernes særegne brug af byrummet kalder på opmærksomhed og analytisk undren: Hvordan kan vi forstå et fænomen som pa...

  5. Idrætten som social generator

    DEFF Research Database (Denmark)

    Kural, René

    2002-01-01

    Med henvisning til to svømmehaller i hhv. Manchester og Berlin illustrerers det, hvorledes idrætten, store sportslige begivenheder og sportsfaciliteterne kan fungere som social generator for hele byafsnit.......Med henvisning til to svømmehaller i hhv. Manchester og Berlin illustrerers det, hvorledes idrætten, store sportslige begivenheder og sportsfaciliteterne kan fungere som social generator for hele byafsnit....

  6. Contrasting effects of elevated CO2 and warming on temperature sensitivity of soil organic matter decomposition in a Chinese paddy field.

    Science.gov (United States)

    Chen, Zhaozhi; Wang, Bingyu; Wang, Jinyang; Pan, Genxing; Xiong, Zhengqin

    2015-10-01

    Climate changes including elevated CO2 and temperature have been known to affect soil carbon (C) storage, while the effects of climate changes on the temperature sensitivity of soil organic matter (SOM) are unclear. A 365-day laboratory incubation was used to investigate the temperature sensitivity for decomposition of labile (Q 10-L) and recalcitrant (Q 10-R) SOMs by comparing the time required to decompose a given amount of C at 25 and 35 °C. Soils were collected from a paddy field that was subjected to four treatments: ambient CO2 and temperature, elevated CO2 (500 μmol/mol), enhanced temperature (+2 °C), and their combination. The results showed that the temperature sensitivity of SOM decomposition increased with increasing SOM recalcitrance in this paddy soil (Q 10-L = 2.21 ± 0.16 vs. Q 10-R = 2.78 ± 0.42; mean ± SD). Elevated CO2 and enhanced temperature showed contrasting effects on the temperature sensitivity of SOM decomposition. Elevated CO2 stimulated Q 10-R but had no effect on Q 10-L; in contrast, enhanced temperature increased Q 10-L but had no effect on Q 10-R. Furthermore, the elevated CO2 combined with enhanced temperature treatment significantly increased Q 10-L and Q 10-R by 18.9 and 10.2 %, respectively, compared to the ambient conditions. Results suggested that the responses of SOM to temperature, especially for the recalcitrant SOM pool, were altered by climate changes. The greatly enhanced temperature sensitivity of SOM decomposition by elevated CO2 and temperature indicates that more CO2 will be released to the atmosphere and losses of soil C may be even greater than that previously expected in paddy field.

  7. Can Biochar Protect Labile Organic Matter Against Mineralization in Soil?

    Institute of Scientific and Technical Information of China (English)

    Giovanna B.MELAS; Oriol ORTIZ; Josep M.ALACA(N)IZ

    2017-01-01

    Biochar could help to stabilize soil organic (SOM) matter,thus sequestering carbon (C) into the soil.The aim of this work was to determine an easy method i) to estimate the effects of the addition of biochar and nutrients on the organic matter (SOM)mineralization in an artificial soil,proposed by the Organization for Economic Co-operation and Development (OECD),amended with glucose and ii) to measure the amount of labile organic matter (glucose) that can be sorbed and thus be partially protected in the same soil,amended or not amended with biochar.A factorial experiment was designed to check the effects of three single factors (biochar,nutrients,and glucose) and their interactions on whole SOM mineralization.Soil samples were inoculated with a microbial inoculum and preincubated to ensure that their biological activities were not limited by a small amount of microbial biomass,and then they were incubated in the dark at 21 ℃ for 619 d.Periodical measurements of C mineralized to carbon dioxide (CO2) were carried out throughout the 619-d incubation to allow the mineralization of both active and slow organic matter pools.The amount of sorbed glucose was calculated as the difference between the total and remaining amounts of glucose added in a soil extract.Two different models,the Freundlich and Langmuir models,were selected to assess the equilibrium isotherms of glucose sorption.The CO2-C release strongly depended on the presence of nutrients only when no biochar was added to the soil.The mineralization of organic matter in the soil amended with both biochar and glucose was equal to the sum of the mineralization of the two C sources separately.Furthermore,a significant amount of glucose can be sorbed on the biochar-amended soil,suggesting the involvement of physico-chemical mechanisms in labile organic matter protection.

  8. Reactivity of Organic Matter and other Reductants in Aquifer Sediments

    NARCIS (Netherlands)

    Hartog, N.

    2003-01-01

    The molecular composition and the carbon isotope signature of sedimentary organic matter (SOM) and indicate that SOM is predominantly derived from higher land plants in sediments of both terrestrial as marine origins. The reactivity of SOM in the aquifer sediments studied is determined by the extent

  9. SOMPROF: A vertically explicit soil organic matter model

    NARCIS (Netherlands)

    Braakhekke, M.C.; Beer, M.; Hoosbeek, M.R.; Kruijt, B.; Kabat, P.

    2011-01-01

    Most current soil organic matter (SOM) models represent the soil as a bulk without specification of the vertical distribution of SOM in the soil profile. However, the vertical SOM profile may be of great importance for soil carbon cycling, both on short (hours to years) time scale, due to

  10. Soil organic matter composition and quality across fire severity gradients in coniferous and deciduous forests of the southern boreal region

    Science.gov (United States)

    Miesel, Jessica R.; Hockaday, William C.; Kolka, Randall K.; Townsend, Philip A.

    2015-06-01

    Recent patterns of prolonged regional drought in southern boreal forests of the Great Lakes region, USA, suggest that the ecological effects of disturbance by wildfire may become increasingly severe. Losses of forest soil organic matter (SOM) during fire can limit soil nutrient availability and forest regeneration. These processes are also influenced by the composition of postfire SOM. We sampled the forest floor layer (i.e., full organic horizon) and 0-10 cm mineral soil from stands dominated by coniferous (Pinus banksiana Lamb.) or deciduous (Populus tremuloides Michx.) species 1-2 months after the 2011 Pagami Creek wildfire in northern Minnesota. We used solid-state 13C NMR to characterize SOM composition across a gradient of fire severity in both forest cover types. SOM composition was affected by fire, even when no statistically significant losses of total C stocks were evident. The most pronounced differences in SOM composition between burned and unburned reference areas occurred in the forest floor for both cover types. Carbohydrate stocks in forest floor and mineral horizons decreased with severity level in both cover types, whereas pyrogenic C stocks increased with severity in the coniferous forest floor and decreased in only the highest severity level in the deciduous forest floor. Loss of carbohydrate and lignin pools contributed to a decreased SOM stability index and increased decomposition index. Our results suggest that increases in fire severity expected to occur under future climate scenarios may lead to changes in SOM composition and dynamics with consequences for postfire forest recovery and C uptake.

  11. Missing links in the root-soil organic matter continuum

    Energy Technology Data Exchange (ETDEWEB)

    O' Brien, Sarah L. [Argonne National Laboratory (ANL); Iversen, Colleen M [ORNL

    2009-01-01

    The soil environment remains one of the most complex and poorly understood research frontiers in ecology. Soil organic matter (SOM), which spans a continuum from fresh detritus to highly processed, mineral-associated organic matter, is the foundation of sustainable terrestrial ecosystems. Heterogeneous SOM pools are fueled by inputs from living and dead plants, driven by the activity of micro- and mesofauna, and are shaped by a multitude of abiotic factors. The specialization required to measure unseen processes that occur on a wide range of spatial and temporal scales has led to the partitioning of soil ecology research across several disciplines. In the organized oral session 'Missing links in the root-soil organic matter continuum' at the annual Ecological Society of America meeting in Albuquerque, NM, USA, we joined the call for greater communication and collaboration among ecologists who work at the root-soil interface (e.g. Coleman, 2008). Our goal was to bridge the gap between scientific disciplines and to synthesize disconnected pieces of knowledge from root-centric and soil-centric studies into an integrated understanding of belowground ecosystem processes. We focused this report around three compelling themes that arose from the session: (1) the influence of the rhizosphere on SOM cycling, (2) the role of soil heterotrophs in driving the transformation of root detritus to SOM, and (3) the controlling influence of the soil environment on SOM dynamics. We conclude with a discussion of new approaches for gathering data to bridge gaps in the root-SOM continuum and to inform the next generation of ecosystem models. Although leaf litter has often been considered to be the main source of organic inputs to soil, Ann Russell synthesized a convincing body of work demonstrating that roots, rather than surface residues, control the accumulation of SOM in a variety of ecosystems. Living roots, which are chemically diverse and highly dynamic, also influence a

  12. Microphytobenthos and benthic macroalgae determine sediment organic matter composition in shallow photic sediments

    NARCIS (Netherlands)

    Hardison, A.K.; Canuel, E.A/; Anderson, I.C.; Tobias, C.R.; Veuger, B.; Waters, M.N.

    2013-01-01

    Microphytobenthos and benthic macroalgae play an important role in system metabolism within shallow coastal bays. However, their independent and interactive influences on sediment organic matter (SOM) are not well understood. We investigated the influence of macroalgae and microphytobenthos on SOM

  13. Two-dimensional NMR spectroscopy strongly enhances soil organic matter composition analysis

    Science.gov (United States)

    Soucemarianadin, Laure; Erhagen, Björn; Öquist, Mats; Nilsson, Mats; Hedenström, Mattias; Schleucher, Jürgen

    2016-04-01

    Soil organic matter (SOM) is the largest terrestrial carbon pool and strongly affects soil properties. With climate change, understanding SOM processes and turnover and how they could be affected by increasing temperatures becomes critical. This is particularly key for organic soils as they represent a huge carbon pool in very sensitive ecosystems, like boreal ecosystems and peatlands. Nevertheless, characterization of SOM molecular composition, which is essential to elucidate soil carbon processes, is not easily achieved, and further advancements in that area are greatly needed. Solid-state one-dimensional (1D) 13C nuclear magnetic resonance (NMR) spectroscopy is often used to characterize its molecular composition, but only provides data on a few major functional groups, which regroup many different molecular fragments. For instance, in the carbohydrates region, signals of all monosaccharides present in many different polymers overlap. This overlap thwarts attempts to identify molecular moieties, resulting in insufficient information to characterize SOM composition. Here we show that two-dimensional (2D) liquid-state 1H-13C NMR spectra provided much richer data on the composition of boreal plant litter and organic surface soil. The 2D spectra indeed resolved overlaps observed in 1D 13C spectra and displayed signals from hundreds of identifiable molecular groups. For example, in the aromatics region, signals from individual lignin units could be recognized. It was hence possible to follow the fate of specific structural moieties in soils. We observed differences between litter and soil samples, and were able to relate them to the decomposition of identifiable moieties. Sample preparation and data acquisition were both simple and fast. Further, using multivariate data analysis, we aimed at linking the detailed chemical fingerprints of SOM to turnover rates in a soil incubation experiment. With the multivariate models, we were able to identify specific molecular

  14. [Study on mechanism of SOM stabilization of paddy soils under long-term fertilizations].

    Science.gov (United States)

    Luo, Lu; Zhou, Ping; Tong, Cheng-Li; Shi, Hui; Wu, Jin-Shui; Huang, Tie-Ping

    2013-02-01

    Fourier transform infrared spectroscopy (FTIR) was applied to study the structure of soil organic matter (SOM) of paddy soils under long-term different fertilization treatments. The aim was to clarify the different distribution of SOM between different fertilization methods and between topsoil and subsoil, and to explore the stability mechanism of SOM under different fertilization treatments. The results showed that the content of topsoil organic carbon (SOC) was the highest under organic-inorganic fertilizations, with the increment of SOC by 18.5%, 12.9% and 18.4% under high organic manure (HOM), low organic manure (LOM) and straw returning (STW) respectively compared with no fertilization treatment (CK). The long-term fertilizations also changed the chemical structure of SOM. As compared with CK, different fertilization treatments increased the functional group absorbing intensity of chemical resistance compounds (aliphatic, aromaticity), carbohydrate and organo-silicon compounds, which was the most distinctive under treatments of HOM, LOM and STW. For example, the absorbing intensity of alkyl was 0.30, 0.25 and 0.29 under HOM, LOM and STW, respectively. These values were increased by 87% , 56% and 81% as compared with that under CK treatment. The functional group absorbing intensity of SOM in the topsoil was stronger than that in the subsoil, with the most distinctive difference under HOM, LOM and STW treatments. The present research indicated that the enhanced chemical resistance of functional group of SOM may contribute to the high contents of SOC in the paddy soils under long-term organic-inorganic fertilizations, which also suggested a chemical stabilization mechanism of SOM in the paddy soils.

  15. Kan Batman dateres? Om massekommunikasjonen som kulturhistorie

    Directory of Open Access Journals (Sweden)

    Hans Frederik Dahl

    1990-08-01

    Full Text Available Hans Frederik Dahls artikel er et bud på om massekommunikationen kan tænkes ind i kulturhistorien.Første halvdel af artiklen fremhæver de prob- lemer, det rejser, når massekommunikation med dens karakteristika i form af serialitet, triviatitet og internationalitet skal reflekteres i forhold til en kulturhistorisk tradition, som normalt tænker i begreber som tidsånd, kunstnerisk originalitet og nationalt særpræg. Sidste halvdel focuserer på tre centrale aspekter ved massekommunikationen, som også er af- gørende for dens kulturhistorie: dens nære forbindelse til musikken, dens internationale karakter og dens konstante tilbagevenden til tidligere pro- dukter.

  16. Kan Batman dateres? Om massekommunikasjonen som kulturhistorie

    Directory of Open Access Journals (Sweden)

    Hans Frederik Dahl

    1990-06-01

    Full Text Available Hans Frederik Dahls artikel er et bud på om massekommunikationen kan tænkes ind i kulturhistorien.Første halvdel af artiklen fremhæver de prob- lemer, det rejser, når massekommunikation med dens karakteristika i form af serialitet, triviatitet og internationalitet skal reflekteres i forhold til en kulturhistorisk tradition, som normalt tænker i begreber som tidsånd, kunstnerisk originalitet og nationalt særpræg. Sidste halvdel focuserer på tre centrale aspekter ved massekommunikationen, som også er af- gørende for dens kulturhistorie: dens nære forbindelse til musikken, dens internationale karakter og dens konstante tilbagevenden til tidligere pro- dukter.

  17. Kunst som metode i interaktiv forskning

    DEFF Research Database (Denmark)

    Jensen, Julie Borup

    for at påvirke feltet og skabe ny viden i interaktionsprocesser, bygger dette på en antagelse om, at interaktion mellem mennesker betjener sig af såkaldte medier for kommunikation og læring (Säljö 2003:196, Bruner 1996:76). I denne forståelse kan et medium eksempelvis være sproget, skriften, praksisrutiner, men...... et medium kan også være kunst og kunstværker. Kunstværker kan ses som et udtryk for en given kulturs antagelser om virkeligheden (Bruner 1996:), men også som en provokation eller udfordring til denne virkelighedsopfattelse (Darsø 2004). I forlængelse heraf kan kunst og kunstværker ses som...

  18. Om filmteori og filmhistorie: Stumfilmen som eksempel

    Directory of Open Access Journals (Sweden)

    Casper Tybjerg

    1995-09-01

    Full Text Available Tilbage til filmene og filmmagerne siger Casper Tybjerg i denne artikel. Han plæderer dog ikke nødvendigvis for en tilbagevending til "gammel- dags filmhistorieskrivning" og til en fokusering kun på film som æstetik og kunst. Med udgangspunkt i konkrete overvejelser over den danske stumfilm og gennemgang af væsentlige nyere filmhistoriske værker og teorier polemiserer han mod det han opfatter som upræcise og meget abstrakte kulturalistiske positioner, som enten glemmer de konkrete film eller overbetoner det blot formelle i filmhistorien. Samtidig tegner han også et levende billede af den kultur og de betingelser den tidlige film blev til i.

  19. Musikterapi som samværsform

    DEFF Research Database (Denmark)

    Ridder, Hanne Mette Ochsner

    2005-01-01

    Det kan være svært for mennesker med omfattende demenssymptomer at deltage i aktiviteter eller samvær med andre – og uden interaktion med andre kan det være svært at få dækket psykosociale behov. Der er derfor brug for samvær og aktiviteter som er specielt tilrettelagt for at opfylde psykosociale...... erfaringer indenfor demensområdet. Der vil i foredraget blive taget udgangspunkt i praksiserfaring som musikterapeut på Plejehjemmet Caritas samt i et forskningsprojekt om individuel musikterapi, hvorfra der bliver vist videoeksempler....

  20. Microphytobenthos and benthic macroalgae determine sediment organic matter composition in shallow photic sediments

    Directory of Open Access Journals (Sweden)

    A. K. Hardison

    2013-08-01

    Full Text Available Microphytobenthos and benthic macroalgae play an important role in system metabolism within shallow coastal bays. However, their independent and interactive influences on sediment organic matter (SOM are not well understood. We investigated the influence of macroalgae and microphytobenthos on SOM quantity and quality in an experimental mesocosm system using bulk and molecular level (total hydrolyzable amino acids, THAA; phospholipid linked fatty acids, PLFA; pigment analyses. Our experiment used an incomplete factorial design made up of two factors, each with two levels: (1 light (ambient vs. dark and (2 macroalgae (presence vs. absence of live macroalgae. Over the course of the 42-day experiment, total organic carbon (TOC and total nitrogen (TN increased under ambient light by 173 ± 14 and 141 ± 7%, respectively, compared to in the dark (78 ± 29 and 39 ± 22%. THAA comprised a substantial fraction of SOM (~ 16% of TOC, 35% of TN and followed TOC and TN accumulation patterns. Mole percent composition of the THAA pool indicated that SOM was composed of more labile organic material (e.g., L-glutamic acid, phenylalanine under ambient light conditions while SOM in dark treatments was more degraded, with higher proportions of glycine and D-alanine. PLFA content, which represents viable biomass, made up ~ 1% of TOC and contained high levels of algal fatty acids in the light, particularly PLFA derived from diatoms. In the presence of microphytobenthos (i.e., light and macroalgae treatments, SOM lability increased, resulting in the observed increases in bacterial PLFA concentrations. Macroalgae, which were added to half of the light treatments, decreased SOM accumulation compared to light treatments without macroalgae, with TOC and TN increasing by only 130 ± 32 and 94 ± 24%, respectively. This decrease likely resulted from shading by macroalgae, which reduced production of microphytobenthos. The presence of macroalgae decreased SOM lability as

  1. Microphytobenthos and benthic macroalgae determine sediment organic matter composition in shallow photic sediments

    Science.gov (United States)

    Hardison, A. K.; Canuel, E. A.; Anderson, I. C.; Tobias, C. R.; Veuger, B.; Waters, M. N.

    2013-08-01

    Microphytobenthos and benthic macroalgae play an important role in system metabolism within shallow coastal bays. However, their independent and interactive influences on sediment organic matter (SOM) are not well understood. We investigated the influence of macroalgae and microphytobenthos on SOM quantity and quality in an experimental mesocosm system using bulk and molecular level (total hydrolyzable amino acids, THAA; phospholipid linked fatty acids, PLFA; pigment) analyses. Our experiment used an incomplete factorial design made up of two factors, each with two levels: (1) light (ambient vs. dark) and (2) macroalgae (presence vs. absence of live macroalgae). Over the course of the 42-day experiment, total organic carbon (TOC) and total nitrogen (TN) increased under ambient light by 173 ± 14 and 141 ± 7%, respectively, compared to in the dark (78 ± 29 and 39 ± 22%). THAA comprised a substantial fraction of SOM (~ 16% of TOC, 35% of TN) and followed TOC and TN accumulation patterns. Mole percent composition of the THAA pool indicated that SOM was composed of more labile organic material (e.g., L-glutamic acid, phenylalanine) under ambient light conditions while SOM in dark treatments was more degraded, with higher proportions of glycine and D-alanine. PLFA content, which represents viable biomass, made up ~ 1% of TOC and contained high levels of algal fatty acids in the light, particularly PLFA derived from diatoms. In the presence of microphytobenthos (i.e., light and macroalgae treatments), SOM lability increased, resulting in the observed increases in bacterial PLFA concentrations. Macroalgae, which were added to half of the light treatments, decreased SOM accumulation compared to light treatments without macroalgae, with TOC and TN increasing by only 130 ± 32 and 94 ± 24%, respectively. This decrease likely resulted from shading by macroalgae, which reduced production of microphytobenthos. The presence of macroalgae decreased SOM lability as well, which

  2. Absorption and fluorescence properties of chromophoric dissolved organic matter of the eastern Bering Sea in the summer with special reference to the influence of a cold pool

    Science.gov (United States)

    D'Sa, E. J.; Goes, J. I.; Gomes, H.; Mouw, C.

    2014-06-01

    The absorption and fluorescence properties of chromophoric dissolved organic matter (CDOM) are reported for the inner shelf, slope waters and outer shelf regions of the eastern Bering Sea during the summer of 2008, when a warm, thermally stratified surface mixed layer lay over a cold pool (CDOM absorption at 355 nm (ag355) and its spectral slope (S) in conjunction with excitation-emission matrix (EEM) fluorescence and parallel factor analysis (PARAFAC) revealed large variability in the characteristics of CDOM in different regions of the Bering Sea. PARAFAC analysis aided in the identification of three humic-like (components one, two and five) and two protein-like (a tyrosine-like component three, and a tryptophan-like component four) components. In the extensive shelf region, average absorption coefficients at 355 nm (ag355, m-1) and DOC concentrations (μM) were highest in the inner shelf (0.342 ± 0.11 m-1, 92.67 ± 14.60 μM) and lower in the middle (0.226 ± 0.05 m-1, 78.38 ± 10.64 μM) and outer (0.185 ± 0.05 m-1, 79.24 ± 18.01 μM) shelves, respectively. DOC concentrations, however were not significantly different, suggesting CDOM sources and sinks to be uncoupled from DOC. Mean spectral slopes S were elevated in the middle shelf (24.38 ± 2.25 μm-1) especially in the surface waters (26.87 ± 2.39 μm-1) indicating high rates of photodegradation in the highly stratified surface mixed layer, which intensified northwards in the northern middle shelf likely contributing to greater light penetration and to phytoplankton blooms at deeper depths. The fluorescent humic-like components one, two, and five were most elevated in the inner shelf most likely from riverine inputs. Along the productive "green belt" in the outer shelf/slope region, absorption and fluorescence properties indicated the presence of fresh and degraded autochthonous DOM. Near the Unimak Pass region of the Aleutian Islands, low DOC and ag355 (mean 66.99 ± 7.94 μM; 0.182 ± 0.05 m-1) and a

  3. Skønlitteraturen som opposition

    DEFF Research Database (Denmark)

    Larsen, Pelle Oliver

    2011-01-01

    Troels Troels-Lund er kendt som foregangsmanden i den første kulturhistoriske bølge i Danmark fra omkring 1880. Hans form for kulturhistorie vandt imidlertid aldrig for alvor faghistorikernes anerkendelse, og Troels-Lund blev udgrænset. Denne artikel går tilbage til 1870’erne og indeholder en ana...

  4. Massemedier som forum for politisk debat

    DEFF Research Database (Denmark)

    Laursen, Bo; Trapp, Leila

    2015-01-01

    Ifølge normative teorier om politisk offentlighed og demokrati bør der i deliberative demokratier som det danske foregå en bred offentlig debat, inden politikere træffer beslutninger. Debatten, der i dagens Danmark hovedsagelig foregår i massemedierne, skal blandt andet sikre, at alle synspunkter...

  5. Brands som brikker i konstruktionen af identitet

    DEFF Research Database (Denmark)

    Hermansen, Judy

    2008-01-01

    Forbrug spiller en vigtig rolle i produktionen af mening og værdier, som kan skabe og vedligeholde både forbrugerens personlige og sociale verden - og derfor er reklame også en vigtig kilde til disse symbolske betydninger. Udgivelsesdato: juni...

  6. Perception som forståelsens grundlag

    DEFF Research Database (Denmark)

    Nielsen, Charlotte Marie Bisgaard

    2005-01-01

    sprogpsykologisk som sense-making procedurer. Perception har ifølge William James at gøre med personers forståelser. Monets katedralmalerier fra Rouen og Cézannes billeder fra Aix-en Provence samt hans Selvportræt med Bowlerhat (Ny Carlsberg Glyptotek) sammenholdes med Merleau-Pontys Perceptionens Primat og...

  7. Værdibasering som kommunal praksis

    DEFF Research Database (Denmark)

    Ostrowski, Kasper

    2009-01-01

    og tværkommunale forskelle foranlediget af kommunalreformen i Danmark. Begrebet ’værdibaseret ledelse’ gestaltes ofte med en både frustrerende lethed og på fascinerende vis som fænomen. Dette har ansporet min interesse for i denne afhandling at undersøge, hvorledes værdibaseret ledelse kan forstås...

  8. Selvrefleksion som uddannelsesgreb – en kritisk diskussion

    DEFF Research Database (Denmark)

    Feilberg, Casper

    2015-01-01

    Hvordan kan ureflekteret motivation gribe forstyrrende ind i de studerendes videnskabelige arbejde, og hvordan kan man som vejleder forholde sig til disse private forhold på en både faglig og etisk forsvarlig måde? I artiklen vises eksempler på, at studerende nemt kan komme til at agere ud fra ur...

  9. Supply Chain Management som interaktionel praksis

    DEFF Research Database (Denmark)

    Smith, Leo Feddersen; Lund, Anders

    2016-01-01

    I dette bidrag undersøger vi Supply Chain Management som en interaktionel praksis forankret i kommunikation. Med udgangspunkt i e-mail korrespondancer undersøger vi, hvordan køber-leverandør forholdet kommunikativt konstitueres mellem to danske SMVer og deres kinesiske leverandører. Det...

  10. Livsvalg konceptualiseret som dynamisk realisering af livsbaner

    DEFF Research Database (Denmark)

    Schnieber, Anette

    2009-01-01

    De valgsituationer, man i daglig tale kender som ”tilværelsens store valg”, mangler definition i den psykologiske litteratur, og det er således ikke klart, hvorvidt og evt. hvorledes disse valg adskiller sig fra andre typer. I artiklen gives en definition af ”de store valg”, og de adskilles fra...

  11. Feltarbejde som læringsrum

    DEFF Research Database (Denmark)

    Lund, Lisbeth Revsbæk

    2010-01-01

    artiklen beskrives, hvordan refleksionsrum og metakommunikative processer opleves af studerende, og hvilken betydning disse rum får for deres forståelse af såvel egne som uddannelsens læreprocesser. Artiklen er en del af en antologi, der tager sit udgangspunkt i de mange rum mellem uddannelse og profession......, databearbejdning, feltarbejde og teaching lab....

  12. The Influence of Land-Use Change on Soil and Dissolved Organic Matter Age, Lability, and Chemical Characteristics in Brazilian Oxisols

    Science.gov (United States)

    James, J. N.; Harrison, R. B.; Gross, C. D.; Dwivedi, P.; Myers, T.; Butman, D. E.

    2017-12-01

    Recent advances in freshwater research indicate that the age of carbon exported from major rivers globally increases with greater human disturbance in the watershed. This implies that human land-use can release old, previously mineral-associated C into solution with subsequent export to groundwater and ultimately freshwater systems where terrestrial organic matter is either mineralized to CO2, stored in aquatic sediments, or exported to the ocean. It is important to understand the mechanisms that cause the release of mineral-bound soil organic matter (SOM) into solution in response to human disturbance and land-use change. To better characterize the response of the total soil organic matter (SOM) pool to disturbance, this study examines the interactions between dissolved and bulk soil pools in response to conversion of Brazilian Cerrado (savannah forest) to Eucalyptus plantations. Water-extractable organic matter (WEOM) was obtained from soil samples down to 150 cm at 4 sites in Sao Paulo State, Brazil. These WEOM samples were characterized using fluorescence and NMR spectroscopy, incubated to assess biolability, and carbon-dated. Simultaneously, bulk mineral soil samples were analyzed for microbial biomass, carbon content and age, and characterized using Fourier Transform Infrared Spectroscopy. FTIR spectra of SOM were obtained by washing subsamples with sodium hypochlorite and subtracting the subsequent mineral matrix spectra from bulk soil spectra. Preliminary results show that microbial biomass decreases much more quickly with depth than WEOM, suggesting that C released into solution from deeper horizons may be less likely to be intercepted, and thus preferentially leached to groundwater. Native Cerrado forests had substantially more roots compared to Eucalyptus, and also released substantially larger quantities of WEOM from their O horizons. Furthermore, the age of WEOM released under Eucalyptus forest was more similar in age to bulk SOM, while Cerrado forest

  13. Varehusbesøget som fornøjeligt hverdagsdrama

    DEFF Research Database (Denmark)

    Bouchet, Julie Kirstine Linderoth; Jantzen, Christian

    2014-01-01

    Artiklen analyserer de koreografiske, scenografiske og dramaturgiske virkemidler, som IKEA har anvendt til at skabe et succesfuldt oplevelsesdesign.......Artiklen analyserer de koreografiske, scenografiske og dramaturgiske virkemidler, som IKEA har anvendt til at skabe et succesfuldt oplevelsesdesign....

  14. "Tryllefløjten" som musik-historisk allegori

    DEFF Research Database (Denmark)

    Jensen, Jørgen I.

    1991-01-01

    Musikhistorie, Mozarts "Tryllefløjten", Mozart som historisk fænomen, oplysningstid, frimureri, musik og religion......Musikhistorie, Mozarts "Tryllefløjten", Mozart som historisk fænomen, oplysningstid, frimureri, musik og religion...

  15. Pool scrubbing

    International Nuclear Information System (INIS)

    Lopez-Jimenez, J.; Herranz, J.; Escudero, M.J.; Espigares, M.M.; Peyres, V.; Polo, J.; Kortz, Ch.; Koch, M.K.; Brockmeier, U.; Unger, H.; Dutton, L.M.C.; Smedley, Ch.; Trow, W.; Jones, A.V.; Bonanni, E.; Calvo, M.; Alonso, A.

    1996-12-01

    The Source Term Project in the Third Frame Work Programme of the European Union Was conducted under and important joined effort on pool scrubbing research. CIEMAT was the Task Manager of the project and several other organizations participated in it: JRC-Ispra, NNC Limited, RUB-NES and UPM. The project was divided into several tasks. A peer review of the models in the pool scrubbing codes SPARC90 and BUSCA-AUG92 was made, considering the different aspects in the hydrodynamic phenomenology, particle retention and fission product vapor abortions. Several dominant risk accident sequences were analyzed with MAAP, SPARC90 and BUSCA-AUG92 codes, and the predictions were compared. A churn-turbulent model was developed for the hydrodynamic behaviour of the pool. Finally, an experimental programme in the PECA facility of CIEMAT was conducted in order to study the decontamination factor under jet injection regime, and the experimental observations were compared with the SPARC and BUSCA codes. (Author)

  16. An isotopic investigation of the temperature response of young and old soil organic matter respiration

    Science.gov (United States)

    Burns, Nancy; Cloy, Joanna; Garnett, Mark; Reay, David; Smith, Keith; Otten, Wilfred

    2010-05-01

    The effect of temperature on rates of soil respiration is critical to our understanding of the terrestrial carbon cycle and potential feedbacks to climate change. The relative temperature sensitivity of labile and recalcitrant soil organic matter (SOM) is still controversial; different studies have produced contrasting results, indicating limited understanding of the underlying relationships between stabilisation processes and temperature. Current global carbon cycle models still rely on the assumption that SOM pools with different decay rates have the same temperature response, yet small differences in temperature response between pools could lead to very different climate feedbacks. This study examined the temperature response of soil respiration and the age of soil carbon respired from radiocarbon dated fractions of SOM (free, intra-aggregate and mineral-bound) and whole soils (organic and mineral layers). Samples were collected from a peaty gley soil from Harwood Forest, Northumberland, UK. SOM fractions were isolated from organic layer (5 - 17 cm) material using high density flotation and ultrasonic disaggregation - designated as free (aggregate (aggregates > 1.8 g cm-3) and mineral-bound (> 1.8 g cm-3) SOM. Fractions were analysed for chemical composition (FTIR, CHN analysis, ICP-OES), 14C (AMS), δ13C and δ15N (MS) and thermal properties (DSC). SOM fractions and bulk soil from the organic layer and the mineral layer (20 - 30 cm) were incubated in sealed vessels at 30 ° C and 10 ° C for 3 or 9 months to allow accumulation of CO2 sufficient for sampling. Accumulated respired CO2 samples were collected on zeolite molecular sieve cartridges and used for AMS radiocarbon dating. In parallel, material from the same fractions and layers were incubated at 10 ° C, 15 ° C, 25 ° C and 30 ° C for 6 months and sampled weekly for CO2 flux measurements using GC chromatography. Initial data have shown radiocarbon ages ranging from modern to 219 y BP in bulk soil from

  17. Statistikeren skiftede spor som 49-årig

    DEFF Research Database (Denmark)

    Sølund, Sune; Rootzén, Helle

    2010-01-01

    En uddannelse til coach har ændret Helle Rototzens liv. Som 49-årig forlod hun et forskerliv på deltid til fordel for en karriere som DTU's eneste kvindelige institutdirektør.......En uddannelse til coach har ændret Helle Rototzens liv. Som 49-årig forlod hun et forskerliv på deltid til fordel for en karriere som DTU's eneste kvindelige institutdirektør....

  18. Poster som et pædagogisk redskab i sygeplejerskeuddannelsen

    DEFF Research Database (Denmark)

    Bagger, Bettan; Kelly, Hélène

    2008-01-01

    Som undervisere har vi gode erfaringer med, at de studerende anvender posters som redskab for formidling af viden. Posterne bruges som udgangspunkt for en mundtlig formidling af faglige perspektiver til de øvrige studerende. Formålet med at anvende formidling ved hjælp af en poster i...

  19. δ13C values of soil organic matter in semiarid grassland with mesquite (Prosopis) encroachment in southeastern Arizona

    Science.gov (United States)

    Biggs, Thomas H.; Quade, Jay; Webb, Robert H.

    2002-01-01

    Over the past century, C3 woody plants and trees have increased in abundance in many semiarid ecosystems, displacing native C4 grasses. Livestock grazing, climatic fluctuations, and fire suppression are several reasons proposed for this shift. Soil carbon isotopic signatures are an ideal technique to evaluate carbon turnover rates in such ecosystems. On the gunnery ranges of Fort Huachuca in southeastern Arizona, study sites were established on homogeneous granitic alluvium to investigate the effects of fire frequency on δ13C values in surface soil organic matter (SOM). These ranges have had no livestock grazing for 50 years and a well-documented history of fires. Prosopis velutina Woot. (mesquite) trees have altered SOM δ13C pools by the concentration of plant nutrients and the addition of isotopically light litter. These soil carbon changes do not extend beyond canopy margins. Elevated total organic carbon (TOC), plant nutrient (N and P) concentrations, and depleted SOM δ13C values are associated with C3Prosopis on an unburned plot, which enables recognition of former Prosopis-occupied sites on plots with recent fire histories. Elevated nutrient concentrations associated with former Prosopis are retained in SOM for many decades. Surface SOM δ13C values indicate the estimated minimum turnover time of C4-derived carbon beneath large mature Prosopis is about 100–300 years. In contrast, complete turnover of original C3 carbon to C4 carbon under grasslands is estimated to take a minimum of 150–500 years. Our study confirms that C4 grass cover has declined over the past 100 years, although isolated C3 trees or shrubs were not uncommon on the historic C4-dominated grasslands. We find evidence in surface soil layers for a modern C3 plant expansion reflected in the substantial shift of SOM δ13C values from C4 grasses to C3 shrublands.

  20. Persistence of soil organic matter as an ecosystem property

    Energy Technology Data Exchange (ETDEWEB)

    Schmidt, M.W.; Torn, M. S.; Abiven, S.; Dittmar, T.; Guggenberger, G.; Janssens, I.A.; Kleber, M.; Kögel-Knabner, I.; Lehmann, J.; Manning, D.A.C.; Nannipieri, P.; Rasse, D.P.; Weiner, S.; Trumbore, S.E.

    2011-08-15

    Globally, soil organic matter (SOM) contains more than three times as much carbon as either the atmosphere or terrestrial vegetation. Yet it remains largely unknown why some SOM persists for millennia whereas other SOM decomposes readily—and this limits our ability to predict how soils will respond to climate change. Recent analytical and experimental advances have demonstrated that molecular structure alone does not control SOM stability: in fact, environmental and biological controls predominate. Here we propose ways to include this understanding in a new generation of experiments and soil carbon models, thereby improving predictions of the SOM response to global warming.

  1. Subsurface oxidation for micropatterning silicon (SOMS).

    Science.gov (United States)

    Zhang, Feng; Sautter, Ken; Davis, Robert C; Linford, Matthew R

    2009-02-03

    Here we present a straightforward patterning technique for silicon: subsurface oxidation for micropatterning silicon (SOMS). In this method, a stencil mask is placed above a silicon surface. Radio-frequency plasma oxidation of the substrate creates a pattern of thicker oxide in the exposed regions. Etching with HF or KOH produces very shallow or much higher aspect ratio features on silicon, respectively, where patterning is confirmed by atomic force microscopy, scanning electron microscopy, and optical microscopy. The oxidation process itself is studied under a variety of reaction conditions, including higher and lower oxygen pressures (2 and 0.5 Torr), a variety of powers (50-400 W), different times and as a function of reagent purity (99.5 or 99.994% oxygen). SOMS can be easily executed in any normal chemistry laboratory with a plasma generator. Because of its simplicity, it may have industrial viability.

  2. Sæbeopera som Forestillingsgenererende Teknologi

    DEFF Research Database (Denmark)

    Waltorp, Karen

    2013-01-01

    Gennem en række empiriske eksempler fra Mauretanien, Danmark og Sydafrika analyserer artiklen dramaserier på tv som en art social teknologi, der tillader infor- manterne at generere forestillinger om andre liv og andre verdener, der på én gang er langt væk og tæt på. 'Soap operas' produceret i USA...

  3. Rousseau som modsvar til forceret talentudvikling

    DEFF Research Database (Denmark)

    Holm, Claus; Nielsen, Jens Christian

    2015-01-01

    pædagogisk syn på børn og unges udvikling. Men dette syn er nu under pres. Det kommer for eksempel til udtryk, når en international idrætsaktør som FC Barcelona vil oprette elitært orienterede fodboldakademier for børn ned til 6-årsalderen i Danmark. Men inspireret af filosoffen Jean-Jacques Rousseau og...

  4. Schelling og Nietzsche som kritikere af Descartes

    DEFF Research Database (Denmark)

    Liisberg, Sune

    2008-01-01

    : 'Hvad er det første for mig' - og svaret var: 'Det er jeg selv'. Cogito-argumentet, der implicerer en forudgående beslutning om at drage alt i tvivl, manifesterer således en historisk enestående 'frigørelse fra al autoritet' (Schelling). Ifølge Schelling - der ligesom Schopenhauer og Nietzsche havde...... blik for, at cogito-argumentet og dets problemer har med dets sprogbundethed at gøre - er ytringsdimensionen nu helt afgørende for cogito-argumentets meningsfuldhed, da allerede 'den blotte tanke 'Jeg er' kan forstås som en indre ytring og forudsætter et talende jeg'. Nietzsche henleder opmærksomheden...... på, at 'eftersom Descartes formulerer cogito-argumentet sprogligt, kan det ikke være nogen umiddelbar, første erkendelse'. Nietzsche antager nemlig, at Descartes selv fejlagtigt betragtede cogito-argumentet som en umiddelbar vished - altså strengt taget ikke som et argument. Men Descartes blev...

  5. Kierkegaard som eksistentiel fænomenolog

    DEFF Research Database (Denmark)

    Kierkegaard som eksistentiel fænomenolog er en antologi, som fremhæver de fænomenologiske aspekter i Kierkegaards beskrivelser af de grundlæggende fænomener i den menneskelige tilværelse. Den fokuserer på Kierkegaards anskuelse af mennesket som en konkret eksisterende person, et tænkende, følende...... og handlende subjekt, der altid har til opgave at forholde sig til sig selv, sin omverden og de andre. Bogen behandler for det første Kierkegaards eget fænomenologiske projekt og hans analyser af angst, fortvivlelse, blufærdighed, samvittighed, selvbedrag og autenticitet. For det andet hans forhold...... til samtidens eksistentielle tænkning (bl.a. Schelling og Poul Martin Møller) og ikke mindst hans forhold til eftertidens eksistentielle tænkning (bl.a. Jaspers, Wittgenstein, Agampen og Zisek). Og for det tredje Kierkegaards betydning for den senere eksistentielle psykologi og psykiatri....

  6. Det nordiske som brandværdi

    DEFF Research Database (Denmark)

    Hermansen, Judy

    2009-01-01

    Kommunikation spiller en vigtig rolle for, hvilke associationer forbrugeren har til brandet. Og da brand image består af summen af alle corporate aktiviteter, er der ifølge Roncha især én fællesnævner, som styrker strategierne bag nordisk brand management: Opbygningen af et globalt og konsistent...... brand under en nordisk designparaply, fordi design i mange år reelt har været en integreret del af det kulturelle og samfundsmæssige liv i Skandinavien. Men ikke alle nordiske designere, er tilfredse med de stilistiske associationer og begrænsninger, som er vokset op omkring det nordiske brand. Derfor...... er det også vigtigt at arbejde aktivt på at udvikle dets symbolske værdi. Der er ifølge Roncha en unik chance for at skabe et bæredygtigt brand, som ikke kun handler om bestemte stilarter eller kunstneriske værdier, men også om kvalitet og innovation. Udgivelsesdato: April...

  7. Using a Mechanistic Reactive Transport Model to Represent Soil Organic Matter Dynamics and Climate Sensitivity

    Science.gov (United States)

    Guerry, N.; Riley, W. J.; Maggi, F.; Torn, M. S.; Kleber, M.

    2011-12-01

    The nature of long term Soil Organic Matter (SOM) dynamics is uncertain and the mechanisms involved are crudely represented in site, regional, and global models. Recent work challenging the paradigm that SOM is stabilized because of its sequential transformations to more intrinsically recalcitrant compounds motivated us to develop a mechanistic modeling framework that can be used to test hypotheses of SOM dynamics. We developed our C cycling model in TOUGHREACT, an established 3-dimensional reactive transport solver that accounts for multiple phases (aqueous, gaseous, sorbed), multiple species, advection and diffusion, and multiple microbial populations. Energy and mass exchange through the soil boundaries are accounted for via ground heat flux, rainfall, C sources (e.g., exudation, woody, leaf, root litter) and C losses (e.g., CO2 emissions and DOC deep percolation). SOM is categorized according to the various types of compounds commonly found in the above mentioned C sources and microbial byproducts, including poly- and monosaccharides, lignin, amino compounds, organic acids, nucleic acids, lipids, and phenols. Each of these compounds is accounted for by one or more representative species in the model. A reaction network was developed to describe the microbially-mediated processes and chemical interactions of these species, including depolymerization, microbial assimilation, respiration and deposition of byproducts, and incorporation of dead biomass into SOM stocks. Enzymatic reactions are characterized by Michaelis-Menten kinetics, with maximum reaction rates determined by the species' O/C ratio. Microbial activity is further regulated by soil moisture content, O2 availability, pH, and temperature. For the initial set of simulations, literature values were used to constrain microbial Monod parameters, Michaelis-Menten parameters, sorption parameters, physical protection, partitioning of microbial byproducts, and partitioning of litter inputs, although there is

  8. Soil organic matter in fire-affected pastures and in an Araucaria forest in South-Brazilian Leptosols

    Directory of Open Access Journals (Sweden)

    Mariana da Luz Potes

    2012-05-01

    Full Text Available The objective of this work was to evaluate the distribution pattern and composition of soil organic matter (SOM and its physical pools of Leptosols periodically affected by fire over the last 100 years in South Brazil. Soil samples at 0-5, 5-10, and 10-15 cm depths were collected from the following environments: native pasture without burning in the last year and grazed with 0.5 livestock per hectare per year (1NB; native pasture without burning in the last 23 years and grazed with 2.0 livestock per hectare per year (23NB; and an Araucaria forest (AF. Physical fractionation was performed with the 0-5 and 5-10 cm soil layers. Soil C and N stocks were determined in the three depths and in the physical pools, and organic matter was characterized by infrared spectroscopy and thermogravimetry. The largest C stocks in all depths and physical pools were found under the AF. The 23NB environment showed the lowest soil C and N stocks at the 5-15 cm depth, which was related to the end of burning and to the higher grazing intensity. The SOM of the occluded light fraction showed a greater chemical recalcitrance in 1NB than in 23NB. Annual pasture burning does not affect soil C stocks up to 15 cm of depth.

  9. Earthworm effects on the incorporation of litter C and N into soil organic matter in a sugar maple forest.

    Science.gov (United States)

    Fahey, Timothy J; Yavitt, Joseph B; Sherman, Ruth E; Maerz, John C; Groffman, Peter M; Fisk, Melany C; Bohlen, Patrick J

    2013-07-01

    To examine the mechanisms of earthworm effects on forest soil C and N, we double-labeled leaf litter with 13C and 15N, applied it to sugar maple forest plots with and without earthworms, and traced isotopes into soil pools. The experimental design included forest plots with different earthworm community composition (dominated by Lumbricus terrestris or L. rubellus). Soil carbon pools were 37% lower in earthworm-invaded plots largely because of the elimination of the forest floor horizons, and mineral soil C:N was lower in earthworm plots despite the mixing of high C:N organic matter into soil by earthworms. Litter disappearance over the first winter-spring was highest in the L. terrestris (T) plots, but during the warm season, rapid loss of litter was observed in both L. rubellus (R) and T plots. After two years, 22.0% +/- 5.4% of 13C released from litter was recovered in soil with no significant differences among plots. Total recovery of added 13C (decaying litter plus soil) was much higher in no-worm (NW) plots (61-68%) than in R and T plots (20-29%) as much of the litter remained in the former whereas it had disappeared in the latter. Much higher percentage recovery of 15N than 13C was observed, with significantly lower values for T than R and NW plots. Higher overwinter earthworm activity in T plots contributed to lower soil N recovery. In earthworm-invaded plots isotope enrichment was highest in macroaggregates and microaggregates whereas in NW plots silt plus clay fractions were most enriched. The net effect of litter mixing and priming of recalcitrant soil organic matter (SOM), stabilization of SOM in soil aggregates, and alteration of the soil microbial community by earthworm activity results in loss of SOM and lowering of the C:N ratio. We suggest that earthworm stoichiometry plays a fundamental role in regulating C and N dynamics of forest SOM.

  10. Preservation of labile organic matter in soils of drained thaw lakes in Northern Alaska

    Science.gov (United States)

    Mueller, Carsten W.; Rethemeyer, Janet; Kao-Kniffin, Jenny; Löppmann, Sebastian; Hinkel, Kenneth; Bockheim, James

    2014-05-01

    A large number of studies predict changing organic matter (OM) dynamics in arctic soils due to global warming. In contrast to rather slowly altering bulk soil properties, single soil organic matter (SOM) fractions can provide a more detailed picture of the dynamics of differently preserved SOM pools in climate sensitive arctic regions. By the study of the chemical composition of such distinctive SOM fractions using nuclear magnetic resonance spectroscopy (NMR) together with radiocarbon analyses it is possible to evaluate the stability of the major OM pools. Approximately 50-75% of Alaska's Arctic Coastal Plain is covered with thaw lakes and drained thaw lakes that follow a 5,000 yr cycle of development (between creation and final drainage), thus forming a natural soil chronosequence. The drained thaw lakes offer the possibility to study SOM dynamics affected by permafrost processes over millennial timescales. In April 2010 we sampled 16 soil cores (including the active and permanent layer) reaching from young drained lakes (0-50 years since drainage) to ancient drained lakes (3000-5500 years since drainage). Air dried soil samples from soil horizons of the active and permanent layer were subjected to density fractionation in order to differentiate particulate OM and mineral associated OM. The chemical composition of the SOM fractions was analyzed by 13C CPMAS NMR spectroscopy. For a soil core of a young and an ancient drained thaw lake basin we also analyzed the 14C content. For the studied soils we can show that up to over 25 kg OC per square meter are stored mostly as labile, easily degradable organic matter rich in carbohydrates. In contrast only 10 kg OC per square meter were sequestered as presumably more stable mineral associated OC dominated by aliphatic compounds. Comparable to soils of temperate regions, we found small POM (dating we could show the stabilization of younger more labile OM at greater depth in buried O horizons. Additionally the study of the

  11. Arbejdspladsen som læringsmiljø

    DEFF Research Database (Denmark)

    Andersen, Vibeke; Hoyrup Pedersen, Steen

    Læring på arbejdspladsen er kommet i fokus både nationalt og internationalt som et stadigt vigtigere svar på videnssamfundets hurtigt eskalerende behov for kompetenceudvikling. Selvfølgelig kan arbejdspladslæring ikke erstatte de formaliserede erhvervs- og efteruddannelser, men arbejdspladsen er...... Workplace Learning. Konsortiet gennemfører i perioden 2001-2004 et større forskningsprogram, der udforsker læreprocesser i arbejdslivet og i samspillet mellem arbejdspladser og det formelle uddannelsessystem. Forskningsprogrammet er finansieret af Undervisningsministeriet og fokuserer primært på de...

  12. Minihusfellesskap som verkemiddel i stadsutvikling av Undredal

    OpenAIRE

    Underdal, Brita

    2017-01-01

    Små bygdesamfunn i Noreg slit med nedgang i folketalet, og det går ut over utvikling, handel og trivsel hjå dei som vert verande i bygda. I verste fall blir bygdene heilt fråflytta, husa forfell og naturressursane går til spille. Dette kan vere framtidsbiletet til Undredal om ikkje noko vert gjort. På 20 år har folketalet gått ned frå 130 innbyggjarar til 70. Dersom utviklinga ikkje stagnerer, vil bygda snart vere tom for fastbuande. Oppgåva stiller difor spørsmålet: Korleis kan ein auk...

  13. IKT som empowerment af lærer og elever!

    DEFF Research Database (Denmark)

    Christiansen, René B.; Binggeli, Andreas

    2011-01-01

    I denne korte artikel ønsker vi at pege på at ikt kan fungere som empowerment for både lærere og elever i skolen. It optræder i forvejen i alt for mange menneskers bevidsthed som en barriere eller som en sten i den pædagogiske sundhedssandal. Vi har begge på egen krop oplevet at arbejdet med ny t...

  14. Improved end-member characterization of modern organic matter pools in the Ohrid Basin (Albania, Macedonia) and evaluation of new palaeoenvironmental proxies

    Science.gov (United States)

    Holtvoeth, J.; Rushworth, D.; Imeri, A.; Cara, M.; Vogel, H.; Wagner, T.; Wolff, G. A.

    2015-08-01

    We present elemental, lipid biomarker and compound-specific isotope (δ13C, δ2H) data for soils and leaf litter collected in the catchment of Lake Ohrid (Albania, Macedonia), as well as macrophytes, particulate organic matter and sediments from the lake itself. Lake Ohrid provides an outstanding archive of continental environmental change of at least 1.2 M years and the purpose of our study is to ground truth organic geochemical proxies that we developed in order to study past changes in the terrestrial biome. We show that soils dominate the lipid signal of the lake sediments rather than the vegetation or aquatic biomass, while compound-specific isotopes (δ13C, δ2H) determined for n-alkanoic acids confirm a dominant terrestrial source of organic matter to the lake. There is a strong imprint of suberin monomers on the composition of total lipid extracts and chain-length distributions of n-alkanoic acids, n-alcohols, ω-hydroxy acids and α,ω-dicarboxylic acids. Our end-member survey identifies that ratios of mid-chain length suberin-derived to long-chain length cuticular-derived alkyl compounds as well as their average chain length distributions can be used as new molecular proxies of organic matter sources to the lake. We tested these for the 8.2 ka event, a pronounced and widespread Holocene climate fluctuation. In SE Europe climate became drier and cooler in response to the event, as is clearly recognizable in the carbonate and organic carbon records of Lake Ohrid sediments. Our new proxies indicate biome modification in response to hydrological changes, identifying two phases of increased soil OM supply, first from topsoils and then from mineral soils. Our study demonstrates that geochemical fingerprinting of terrestrial OM should focus on the main lipid sources, rather than the living biomass. Both can exhibit climate-controlled variability, but are generally not identical.

  15. Improved end-member characterisation of modern organic matter pools in the Ohrid Basin (Albania, Macedonia) and evaluation of new palaeoenvironmental proxies

    Science.gov (United States)

    Holtvoeth, J.; Rushworth, D.; Copsey, H.; Imeri, A.; Cara, M.; Vogel, H.; Wagner, T.; Wolff, G. A.

    2016-02-01

    We present elemental, lipid biomarker and, in the supplement, compound-specific isotope (δ13C, δ2H) data for soils and leaf litter collected in the catchment of Lake Ohrid (Albania, Macedonia), as well as macrophytes, particulate organic matter and sediments from the lake itself. Lake Ohrid provides an outstanding archive of continental environmental change of at least 1.2 million years and the purpose of our study is to ground truth organic geochemical proxies that we developed in order to study past changes in the terrestrial biome. We show that soils dominate the lipid signal of the lake sediments rather than the vegetation or aquatic biomass. There is a strong imprint of suberin monomers on the composition of total lipid extracts and chain-length distributions of n-alkanoic acids, n-alcohols, ω-hydroxy acids and α, ω-dicarboxylic acids. Our end-member survey identifies that ratios of mid-chain length suberin-derived to long-chain length cuticular-derived alkyl compounds as well as their average chain length distributions can be used as new molecular proxies of organic matter sources to the lake. We tested these for the 8.2 ka event, a pronounced and widespread Holocene climate fluctuation. In SE Europe climate became drier and cooler in response to the event, as is clearly recognisable in the carbonate and organic carbon records of Lake Ohrid sediments. Our new proxies indicate biome modification in response to hydrological changes, identifying two phases of increased soil organic matter (OM) supply, first from soils with moderately degraded OM and then from more degraded soils. Our study demonstrates that geochemical fingerprinting of terrestrial OM should focus on the main lipid sources, rather than the living biomass. Both can exhibit climate-controlled variability, but are generally not identical.

  16. Ecological Value of Soil Organic Matter at Tropical Evergreen Aglaia-Streblus Forest of Meru Betiri National Park, East Java, Indonesia

    Directory of Open Access Journals (Sweden)

    Hari Sulistiyowati

    2016-09-01

    Full Text Available As part of carbon pools, forest soil stores soil organic matter (SOM that contains many elements including organic C, N, P, and K. These elements contribute nutrients for biogeochemical cycles within the ecosystem. This study was done to determine the ecological value of forest soil organic matter at tropical evergreen Aglaia-Streblus forest of Meru Betiri National Park (MBNP, East Java, Indonesia. The data were sampled along gradient topography in Pringtali tropical forest of TMBNP. Direct measurements of soil moisture, temperature, and pH were taken in the field. The soil samples were extracted from 6 points of soil solum using soil auger, and then oven-dried to get value of dry-weight. The elements content of organic C, N, P, and K were analyzed and estimated at the laboratory. The ecoval of SOM was appraised using developed ecological valuation tool. The result showed that SOM contributed higher ecoval of organic C (66.03 Mg ha-1 than other elements. Compared to P and K elements, N had the highest stock of element content. However, comparing to other two tropical forest ecosystems of Asia the ecoval of SOM elements in TMBNP was relatively low because of its natural geomorphological features.The ecoval of SOM elements in TMBNP was relatively low because of its natural geomorphological features. The ecovals contributed about 2.440,64 - 6.955,50 USD or 31.271.923,73 - 89.120.837,23 IDR per hectare of ecological value (d to the ecosystem. This value was mainly contributed by organic C stock in the TMBNP forest SOM. It means the forest SOM had higher element content of organic C than N, P, and K elements. This d value is an indicator for TMBNP to protect the SOM elements meaning protecting their resources to sustain the biogeochemical cycles in the forest ecosystem. All the management and policy correlated to this protected area should consider this valuable information for their plan and actions.

  17. Differences in SOM decomposition and temperature sensitivity among soil aggregate size classes in a temperate grasslands.

    Science.gov (United States)

    Wang, Qing; Wang, Dan; Wen, Xuefa; Yu, Guirui; He, Nianpeng; Wang, Rongfu

    2015-01-01

    The principle of enzyme kinetics suggests that the temperature sensitivity (Q10) of soil organic matter (SOM) decomposition is inversely related to organic carbon (C) quality, i.e., the C quality-temperature (CQT) hypothesis. We tested this hypothesis by performing laboratory incubation experiments with bulk soil, macroaggregates (MA, 250-2000 μm), microaggregates (MI, 53-250 μm), and mineral fractions (MF, temperature and aggregate size significantly affected on SOM decomposition, with notable interactive effects (Ptemperature in the following order: MA>MF>bulk soil >MI(P classes (P temperature is closely associated withsoil aggregation and highlights the complex responses of ecosystem C budgets to future warming scenarios.

  18. Hawaii ESI: POOLS (Anchialine Pool Points)

    Data.gov (United States)

    National Oceanic and Atmospheric Administration, Department of Commerce — This data set contains sensitive biological resource data for anchialine pools in Hawaii. Anchialine pools are small, relatively shallow coastal ponds that occur...

  19. Transformations in soil organic matter and aggregate stability after conversion of Mediterranean forest to agriculture

    Science.gov (United States)

    Recio Vázquez, Lorena; Almendros, Gonzalo; Carral, Pilar; Knicker, Heike; González Pérez, José Antonio; González Vila, Francisco Javier

    2013-04-01

    Conversion of forest ecosystems into croplands often leads to severe decrease of the soil organic matter (SOM) levels with the concomitant deterioration of soil structure. The present research focuses on the effects of cultivation on the stability of soil macroaggregates, as well as on the total quantity and quality of SOM. Three representative soils from central Spain (i.e., Petric Calcisol, Cutanic Luvisol and Calcic Vertisol) were sampled. Each site had natural vegetation (NV) dominated either by characteristic Mediterranean forest (dehesa) or cereal crops (CC) under conventional tillage. For each site, three spatial replicates of the NV and CC were sampled. Soil aggregate stability was measured by the wet sieving method. The structural stability index was then calculated as the mass of aggregated soil (>250 μm) remaining after wet sieving, as a percent of total aggregate weight. The analytical characterization of the SOM was carried out after chemical fractionation for quantifying the different organic pools: free organic matter (FOM), humic acids (HA), fulvic acids (FA) and humin (H). Furthermore, whole soil samples pretreated with 10 % HF solution were analyzed by CP-MAS 13C NMR and the purified HA fraction was characterized by elementary analysis, visible and infrared spectroscopies and Py-GC/MS. A marked reduction in the proportion of stable aggregates when the natural ecosystem was converted to agriculture was observed. Values of the structural stability index (%) changed over from 96.2 to 38.1, 95.1 to 83.7 and 98.5 to 60.6 for the Calcisol, Luvisol and Vertisol respectively. Comparatively higher contents of SOM were found in the soils under NV (11.69 to 0.93, 3.29 to 2.72 and 9.51 to 0.79 g C100 g-1soil) even though a quantitative rearrangement of the SOM pools was noticed. In all sites, the relative contribution of the labile C (FOM) to the total SOM content decreased when the forest soils were converted into croplands, whereas the proportion of both

  20. Current developments in soil organic matter modeling and the expansion of model applications: a review

    International Nuclear Information System (INIS)

    Campbell, Eleanor E; Paustian, Keith

    2015-01-01

    Soil organic matter (SOM) is an important natural resource. It is fundamental to soil and ecosystem functions across a wide range of scales, from site-specific soil fertility and water holding capacity to global biogeochemical cycling. It is also a highly complex material that is sensitive to direct and indirect human impacts. In SOM research, simulation models play an important role by providing a mathematical framework to integrate, examine, and test the understanding of SOM dynamics. Simulation models of SOM are also increasingly used in more ‘applied’ settings to evaluate human impacts on ecosystem function, and to manage SOM for greenhouse gas mitigation, improved soil health, and sustainable use as a natural resource. Within this context, there is a need to maintain a robust connection between scientific developments in SOM modeling approaches and SOM model applications. This need forms the basis of this review. In this review we first provide an overview of SOM modeling, focusing on SOM theory, data-model integration, and model development as evidenced by a quantitative review of SOM literature. Second, we present the landscape of SOM model applications, focusing on examples in climate change policy. We conclude by discussing five areas of recent developments in SOM modeling including: (1) microbial roles in SOM stabilization; (2) modeling SOM saturation kinetics; (3) temperature controls on decomposition; (4) SOM dynamics in deep soil layers; and (5) SOM representation in earth system models. Our aim is to comprehensively connect SOM model development to its applications, revealing knowledge gaps in need of focused interdisciplinary attention and exposing pitfalls that, if avoided, can lead to best use of SOM models to support policy initiatives and sustainable land management solutions. (topical review)

  1. Major Sources of Organic Matter in a Complex Coral Reef Lagoon: Identification from Isotopic Signatures (δ13C and δ15N.

    Directory of Open Access Journals (Sweden)

    Marine J Briand

    Full Text Available A wide investigation was conducted into the main organic matter (OM sources supporting coral reef trophic networks in the lagoon of New Caledonia. Sampling included different reef locations (fringing, intermediate and barrier reef, different associated ecosystems (mangroves and seagrass beds and rivers. In total, 30 taxa of macrophytes, plus pools of particulate and sedimentary OM (POM and SOM were sampled. Isotopic signatures (C and N of each OM sources was characterized and the composition of OM pools assessed. In addition, spatial and seasonal variations of reef OM sources were examined. Mangroves isotopic signatures were the most C-depleted (-30.17 ± 0.41 ‰ and seagrass signatures were the most C-enriched (-4.36 ± 0.72 ‰. Trichodesmium spp. had the most N-depleted signatures (-0.14 ± 0.03 ‰ whereas mangroves had the most N-enriched signatures (6.47 ± 0.41 ‰. The composition of POM and SOM varied along a coast-to-barrier reef gradient. River POM and marine POM contributed equally to coastal POM, whereas marine POM represented 90% of the POM on barrier reefs, compared to 10% river POM. The relative importance of river POM, marine POM and mangroves to the SOM pool decreased from fringing to barrier reefs. Conversely, the relative importance of seagrass, Trichodesmium spp. and macroalgae increased along this gradient. Overall, spatial fluctuations in POM and SOM were much greater than in primary producers. Seasonal fluctuations were low for all OM sources. Our results demonstrated that a large variety of OM sources sustain coral reefs, varying in their origin, composition and role and suggest that δ13C was a more useful fingerprint than δ15N in this endeavour. This study also suggested substantial OM exchanges and trophic connections between coral reefs and surrounding ecosystems. Finally, the importance of accounting for environmental characteristics at small temporal and spatial scales before drawing general patterns is

  2. Multi-site study of additive genetic effects on fractional anisotropy of cerebral white matter: comparing meta and mega analytical approaches for data pooling

    Science.gov (United States)

    Kochunov, Peter; Jahanshad, Neda; Sprooten, Emma; Nichols, Thomas E.; Mandl, René C.; Almasy, Laura; Booth, Tom; Brouwer, Rachel M.; Curran, Joanne E.; de Zubicaray, Greig I.; Dimitrova, Rali; Duggirala, Ravi; Fox, Peter T.; Hong, L. Elliot; Landman, Bennett A.; Lemaitre, Hervé; Lopez, Lorna; Martin, Nicholas G.; McMahon, Katie L.; Mitchell, Braxton D.; Olvera, Rene L.; Peterson, Charles P.; Starr, John M.; Sussmann, Jessika E.; Toga, Arthur W.; Wardlaw, Joanna M.; Wright, Margaret J.; Wright, Susan N.; Bastin, Mark E.; McIntosh, Andrew M.; Boomsma, Dorret I.; Kahn, René S.; den Braber, Anouk; de Geus, Eco JC; Deary, Ian J.; Hulshoff Pol, Hilleke E.; Williamson, Douglas E.; Blangero, John; van ’t Ent, Dennis; Thompson, Paul M.; Glahn, David C.

    2014-01-01

    Combining datasets across independent studies can boost statistical power by increasing the numbers of observations and can achieve more accurate estimates of effect sizes. This is especially important for genetic studies where a large number of observations are required to obtain sufficient power to detect and replicate genetic effects. There is a need to develop and evaluate methods for joint-analytical analyses of rich datasets collected in imaging genetics studies. The ENIGMA-DTI consortium is developing and evaluating approaches for obtaining pooled estimates of heritability through meta-and mega-genetic analytical approaches, to estimate the general additive genetic contributions to the intersubject variance in fractional anisotropy (FA) measured from diffusion tensor imaging (DTI). We used the ENIGMA-DTI data harmonization protocol for uniform processing of DTI data from multiple sites. We evaluated this protocol in five family-based cohorts providing data from a total of 2248 children and adults (ages: 9–85) collected with various imaging protocols. We used the imaging genetics analysis tool, SOLAR-Eclipse, to combine twin and family data from Dutch, Australian and Mexican-American cohorts into one large “mega-family”. We showed that heritability estimates may vary from one cohort to another. We used two meta-analytical (the sample-size and standard-error weighted) approaches and a mega-genetic analysis to calculate heritability estimates across-population. We performed leave-one-out analysis of the joint estimates of heritability, removing a different cohort each time to understand the estimate variability. Overall, meta- and mega-genetic analyses of heritability produced robust estimates of heritability. PMID:24657781

  3. Multi-site study of additive genetic effects on fractional anisotropy of cerebral white matter: Comparing meta and megaanalytical approaches for data pooling.

    Science.gov (United States)

    Kochunov, Peter; Jahanshad, Neda; Sprooten, Emma; Nichols, Thomas E; Mandl, René C; Almasy, Laura; Booth, Tom; Brouwer, Rachel M; Curran, Joanne E; de Zubicaray, Greig I; Dimitrova, Rali; Duggirala, Ravi; Fox, Peter T; Hong, L Elliot; Landman, Bennett A; Lemaitre, Hervé; Lopez, Lorna M; Martin, Nicholas G; McMahon, Katie L; Mitchell, Braxton D; Olvera, Rene L; Peterson, Charles P; Starr, John M; Sussmann, Jessika E; Toga, Arthur W; Wardlaw, Joanna M; Wright, Margaret J; Wright, Susan N; Bastin, Mark E; McIntosh, Andrew M; Boomsma, Dorret I; Kahn, René S; den Braber, Anouk; de Geus, Eco J C; Deary, Ian J; Hulshoff Pol, Hilleke E; Williamson, Douglas E; Blangero, John; van 't Ent, Dennis; Thompson, Paul M; Glahn, David C

    2014-07-15

    Combining datasets across independent studies can boost statistical power by increasing the numbers of observations and can achieve more accurate estimates of effect sizes. This is especially important for genetic studies where a large number of observations are required to obtain sufficient power to detect and replicate genetic effects. There is a need to develop and evaluate methods for joint-analytical analyses of rich datasets collected in imaging genetics studies. The ENIGMA-DTI consortium is developing and evaluating approaches for obtaining pooled estimates of heritability through meta-and mega-genetic analytical approaches, to estimate the general additive genetic contributions to the intersubject variance in fractional anisotropy (FA) measured from diffusion tensor imaging (DTI). We used the ENIGMA-DTI data harmonization protocol for uniform processing of DTI data from multiple sites. We evaluated this protocol in five family-based cohorts providing data from a total of 2248 children and adults (ages: 9-85) collected with various imaging protocols. We used the imaging genetics analysis tool, SOLAR-Eclipse, to combine twin and family data from Dutch, Australian and Mexican-American cohorts into one large "mega-family". We showed that heritability estimates may vary from one cohort to another. We used two meta-analytical (the sample-size and standard-error weighted) approaches and a mega-genetic analysis to calculate heritability estimates across-population. We performed leave-one-out analysis of the joint estimates of heritability, removing a different cohort each time to understand the estimate variability. Overall, meta- and mega-genetic analyses of heritability produced robust estimates of heritability. Copyright © 2014 Elsevier Inc. All rights reserved.

  4. Operation and maintenance techniques of pool and pool water purification system in IMEF

    Energy Technology Data Exchange (ETDEWEB)

    Soong, Woong Sup

    1999-03-01

    IMEF pool is used pass way between pool and hot cell in order to inlet and outlet of fuel pin in cask. All operation is performed conforming with naked eyes. Therefore floating matter is filtered so as to easy under water handling. Also radioactivity in pool water is controlled according to the nuclear law, radioactivity ration maintained less than 15mR/hr on pool side. Perfect operation and maintenance can be achieved well trained operator. Result obtained from the perfection can give more influence over restrain, spreading contamination of radioactivity materials. This report describes operation and maintenance technique of pool water purification system in IMEF. (Author). 7 refs., 13 figs.

  5. Operation and maintenance techniques of pool and pool water purification system in IMEF

    International Nuclear Information System (INIS)

    Soong, Woong Sup

    1999-03-01

    IMEF pool is used pass way between pool and hot cell in order to inlet and outlet of fuel pin in cask. All operation is performed conforming with naked eyes. Therefore floating matter is filtered so as to easy under water handling. Also radioactivity in pool water is controlled according to the nuclear law, radioactivity ration maintained less than 15mR/hr on pool side. Perfect operation and maintenance can be achieved well trained operator. Result obtained from the perfection can give more influence over restrain, spreading contamination of radioactivity materials. This report describes operation and maintenance technique of pool water purification system in IMEF. (Author). 7 refs., 13 figs

  6. Two-dimensional NMR spectroscopy links structural moieties of soil organic matter to the temperature sensitivity of its decomposition

    Science.gov (United States)

    Soucemarianadin, Laure; Erhagen, Björn; Öquist, Mats; Nilsson, Mats; Schleucher, Jürgen

    2015-04-01

    Soil organic matter (SOM) represents a huge carbon pool, specifically in boreal ecosystems. Warming-induced release of large amounts of CO2 from the soil carbon pool might become a significant exacerbating feedback to global warming, if decomposition rates of boreal soils were more sensitive to increased temperatures. Despite a large number of studies dedicated to the topic, it has proven difficult to elucidate how the organo-chemical composition of SOM influences its decomposition, or its quality as a substrate for microbial metabolism. A great part of this challenge results from our inability to achieve a detailed characterization of the complex composition of SOM on the level of molecular structural moieties. 13C nuclear magnetic resonance (NMR) spectroscopy is a common tool to characterize SOM. However, SOM is a very complex mixture and the chemical shift regions distinguished in the 13C NMR spectra often represent many different molecular fragments. For example, in the carbohydrates region, signals of all monosaccharides present in many different polymers overlap. This overlap thwarts attempts to identify molecular moieties, resulting in insufficient information to characterize SOM composition. We applied two-dimensional (2D) NMR to characterize SOM with highly increased resolution. We directly dissolved finely ground litters and forest floors'fibric and humic horizons'of both coniferous and deciduous boreal forests in dimethyl sulfoxide and analyzed the resulting solution with a 2D 1H-13C NMR experiment. In the 2D planes of these spectra, signals of CH groups can be resolved based on their 13C and 1H chemical shifts, hence the resolving power and information content of these NMR spectra is hugely increased. The 2D spectra indeed resolved overlaps observed in 1D 13C spectra, so that hundreds of distinct CH groups could be observed and many molecular fragments could be identified. For instance, in the aromatics region, signals from individual lignin units could

  7. Direct evidence for microbial-derived soil organic matter formation and its ecophysiological controls

    Science.gov (United States)

    Kallenbach, Cynthia M.; Frey, Serita D.; Grandy, A. Stuart

    2016-11-01

    Soil organic matter (SOM) and the carbon and nutrients therein drive fundamental submicron- to global-scale biogeochemical processes and influence carbon-climate feedbacks. Consensus is emerging that microbial materials are an important constituent of stable SOM, and new conceptual and quantitative SOM models are rapidly incorporating this view. However, direct evidence demonstrating that microbial residues account for the chemistry, stability and abundance of SOM is still lacking. Further, emerging models emphasize the stabilization of microbial-derived SOM by abiotic mechanisms, while the effects of microbial physiology on microbial residue production remain unclear. Here we provide the first direct evidence that soil microbes produce chemically diverse, stable SOM. We show that SOM accumulation is driven by distinct microbial communities more so than clay mineralogy, where microbial-derived SOM accumulation is greatest in soils with higher fungal abundances and more efficient microbial biomass production.

  8. Med øjeblikket som udgangspunkt

    DEFF Research Database (Denmark)

    Bo, Inger Glavind

    Artiklen er motiveret af, at Meads temporale analyser tilsyneladende ikke har fået den plads og opmærksomhed, de fortjener, og formålet er at argumentere for, at disse er afgørende for forståelsen af helt centrale aspekter i hans tænkning. Meads udgangspunkt for sin analyse af temporalitet er en...... perspektiv på identitet og social interaktion i hans socialpsykologi. Denne artikels formål er således dobbelt og er for det første at præsentere og diskutere Meads temporale perspektiv som en relevant indgang og nøgle til hans socialpsykologi og sideløbende hermed for det andet at argumentere for, at de...... temporale analyser er centrale for at få greb om Meads genialitet....

  9. Empowerment som frigørelse?

    DEFF Research Database (Denmark)

    Andersen, Pernille Tanggaard

    2010-01-01

    Empowerment er et at tidens modeord, og sættes i forbindelse med vidt forskellige termer eksempelvis personlighedsudvikling, borgerinddragelse og styringsideologi. Begrebet empowerment rummer efterhånden så mange betydninger, at man kan diskuterer selve essensen – i dette kapitel gøres dog et...... forsøg og forskellige dele af begrebet udfoldes. Direkte oversat betyder empowermemt at bemyndige eller sætter i stand til. Empowerment er et ofte anvendt begreb indenfor sundhedsvidenskab og i tilrettelæggelse af sundhedsfremmende initiativer. Begrebet bliver ofte defineret og benyttet forskelligt alt...... efter det bagvedliggende ideologiske perspektiv, og derfor er udgangspunktet i dette kapitel også at illustrerer forskellige ”blikke på empowerment”. Derudover inddrages to eksempler; studier af lokalsamfund og borgerinddragelse og ’den motiverende samtale’ som illustration på, hvilke udfordringer, der...

  10. Børnetegninger som orienteringsspor og forskningsdata

    DEFF Research Database (Denmark)

    Nielsen, Anne Maj

    2012-01-01

    orientation and to discuss how children’s art and drawings can be approached as research data. The construct of children’s art and drawings are comprised of a double approach: Children’s drawings are conceptualized as articulations of not yet thematized emotions, experiences and meaningfulness...... hvordan de er blevet anvendt i forskning samt diskuterer forskellige perspektiver på tegninger som forskningsmateriale og anvendelse af tegninger i forskning. The article aims to illustrate how children’s art and drawings can produce knowledge of children’s personal, experience-based and gendered...... and the articulations include use and learning of visual socio-cultural codes and symbols. The construct comprise an existential-phenomenological and a socio-cultural learning oriented approach. A variation of examples is presented to illustrate the use of children’s drawings in research and to discuss the introduced...

  11. Fænomenologisk dekonstruktion som udspørgning

    DEFF Research Database (Denmark)

    Keller, Kurt Dauer

    Merleau-Ponty skelner udspørgning (interrogation) fra de dominerende opfattelser af refleksion, dialektik og intuition. Udspørgning må betragtes som hans bud på den begrebs- og traditionskritik, Heidegger kaldte ”destruktion”, og som Derrida førte videre under den mere adækvate betegnelse...

  12. Music playlist generation by assimilating GMMs into SOMs

    NARCIS (Netherlands)

    Balkema, Wietse; van der Heijden, Ferdinand

    A method for music playlist generation, using assimilated Gaussian mixture models (GMMs) in self organizing maps (SOMs) is presented. Traditionally, the neurons in a SOM are represented by vectors, but in this paper we propose to use GMMs instead. To this end, we introduce a method to adapt a GMM

  13. Tv-fiktion som tværmedial oplevelsesdesign

    DEFF Research Database (Denmark)

    Sandvik, Kjetil

    2010-01-01

    konstrueres og et bestemt handlingsforløb simuleres, fra de mere kulørte og parapsykologisk funderede fremgangmetoder i serier som The Profiler og Medium, til mere realistiske praksiser som i Rejseholdet og CSI. Og jeg vil endvidere lave en sammenlignende analyse med virkelighedens gerningsstedsefterforskning...

  14. Tema 1: Robotdidaktik. Læringsrobotter som indhold i undervisningen.

    Directory of Open Access Journals (Sweden)

    Jens Jørgen Hansen

    2016-01-01

    Full Text Available Robotter er en teknologi som i disse år bevæger sig ind i skolen. Spørgsmålet er med hvilken didaktisk begrundelse og dermed læringsmæssig relevans man kan arbejde med robotter i skolen? Hvorfor skal eleverne beskæftige sig med robotter? Dette spørgsmål er en opgave for didaktikken at svare på, hvilket sætter robotdidaktik på didaktikkens landkort. I artiklen undersøges en række didaktiske designs fra projektet Fremtek,hvor lærere bl.a. har eksperimenteret med at udvikle undervisningsforløb med humanidrobotter – en slags læringsrobotter -­‐ som omdrejningspunkt (Majgaard 2014. Robotters funktion som indhold i disse didaktiske design analyseres ud fra Frede V. Nielsens fire indholdskategorier: indhold som fænomen, som realia og kontekst, som aktivitet og metode og som personligog social erfaringsfelt. Målet er at udvikle en kritisk og kreativ refleksion over og diskussion af robotteknologi som mål og middel i skolen og andre uddannelsesinstitutioner og bidrage til udvikling af en robotdidaktik, der kan støtte og vejlede undervisere i at foretage didaktiske valg og kvalificere eksperimenter med robotter i undervisningen.

  15. Tema 1: Robotdidaktik. Læringsrobotter som indhold i undervisningen.

    Directory of Open Access Journals (Sweden)

    Jens Jørgen Hansen

    2015-12-01

    Full Text Available Robotter er en teknologi som i disse år bevæger sig ind i skolen. Spørgsmålet er med hvilken didaktisk begrundelse og dermed læringsmæssig relevans man kan arbejde med robotter i skolen? Hvorfor skal eleverne beskæftige sig med robotter? Dette spørgsmål er en opgave for didaktikken at svare på, hvilket sætter robotdidaktik på didaktikkens landkort. I artiklen undersøges en række didaktiske designs fra projektet Fremtek,hvor lærere bl.a. har eksperimenteret med at udvikle undervisningsforløb med humanidrobotter – en slags læringsrobotter -­‐ som omdrejningspunkt (Majgaard 2014. Robotters funktion som indhold i disse didaktiske design analyseres ud fra Frede V. Nielsens fire indholdskategorier: indhold som fænomen, som realia og kontekst, som aktivitet og metode og som personligog social erfaringsfelt. Målet er at udvikle en kritisk og kreativ refleksion over og diskussion af robotteknologi som mål og middel i skolen og andre uddannelsesinstitutioner og bidrage til udvikling af en robotdidaktik, der kan støtte og vejlede undervisere i at foretage didaktiske valg og kvalificere eksperimenter med robotter i undervisningen.

  16. Organic carbon organic matter and bulk density relationships in arid ...

    African Journals Online (AJOL)

    Soil organic matter (SOM) and soil organic carbon (SOC) constitute usually a small portion of soil, but they are one of the most important components of ecosystems. Bulk density (dB or BD) value is necessary to convert organic carbon (OC) content per unit area. Relationships between SOM, SOC and BD were established ...

  17. Soil organic carbon and nitrogen pools drive soil C-CO2 emissions from selected soils in Maritime Antarctica.

    Science.gov (United States)

    Pires, C V; Schaefer, C E R G; Hashigushi, A K; Thomazini, A; Filho, E I F; Mendonça, E S

    2017-10-15

    The ongoing trend of increasing air temperatures will potentially affect soil organic matter (SOM) turnover and soil C-CO 2 emissions in terrestrial ecosystems of Maritime Antarctica. The effects of SOM quality on this process remain little explored. We evaluated (i) the quantity and quality of soil organic matter and (ii) the potential of C release through CO 2 emissions in lab conditions in different soil types from Maritime Antarctica. Soil samples (0-10 and 10-20cm) were collected in Keller Peninsula and the vicinity of Arctowski station, to determine the quantity and quality of organic matter and the potential to emit CO 2 under different temperature scenarios (2, 5, 8 and 11°C) in lab. Soil organic matter mineralization is low, especially in soils with low organic C and N contents. Recalcitrant C form is predominant, especially in the passive pool, which is correlated with humic substances. Ornithogenic soils had greater C and N contents (reaching to 43.15gkg -1 and 5.22gkg -1 for total organic carbon and nitrogen, respectively). C and N were more present in the humic acid fraction. Lowest C mineralization was recorded from shallow soils on basaltic/andesites. C mineralization rates at 2°C were significant lower than at higher temperatures. Ornithogenic soils presented the lowest values of C-CO 2 mineralized by g of C. On the other hand, shallow soils on basaltic/andesites were the most sensitive sites to emit C-CO 2 by g of C. With permafrost degradation, soils on basaltic/andesites and sulfates are expected to release more C-CO 2 than ornithogenic soils. With greater clay contents, more protection was afforded to soil organic matter, with lower microbial activity and mineralization. The trend of soil temperature increases will favor C-CO 2 emissions, especially in the reduced pool of C stored and protected on permafrost, or in occasional Histosols. Copyright © 2016 Elsevier B.V. All rights reserved.

  18. Spatial Heterogeneity of SOM Concentrations Associated with White-rot Versus Brown-rot Wood Decay.

    Science.gov (United States)

    Bai, Zhen; Ma, Qiang; Dai, Yucheng; Yuan, Haisheng; Ye, Ji; Yu, Wantai

    2017-10-23

    White- and brown-rot fungal decay via distinct pathways imparts characteristic molecular imprints on decomposing wood. However, the effect that a specific wood-rotting type of fungus has on proximal soil organic matter (SOM) accumulation remains unexplored. We investigated the potential influence of white- and brown-rot fungi-decayed Abies nephrolepis logs on forest SOM stocks (i.e., soil total carbon (C) and nitrogen (N)) and the concentrations of amino sugars (microbial necromass) at different depths and horizontal distances from decaying woody debris. The brown-rot fungal wood decay resulted in higher concentrations of soil C and N and a greater increase in microbial necromass (i.e., 1.3- to 1.7-fold greater) than the white-rot fungal wood decay. The white-rot sets were accompanied by significant differences in the proportions of the bacterial residue index (muramic acid%) with soil depth; however, the brown-rot-associated soils showed complementary shifts, primarily in fungal necromass, across horizontal distances. Soil C and N concentrations were significantly correlated with fungal rather than bacterial necromass in the brown-rot systems. Our findings confirmed that the brown-rot fungi-dominated degradation of lignocellulosic residues resulted in a greater SOM buildup than the white-rot fungi-dominated degradation.

  19. Evaluation of Strontium Selectivity by Sandia Octahedral Molecular Sieves (SOMS).

    Energy Technology Data Exchange (ETDEWEB)

    Rigali, Mark J.; Stewart, Thomas Austin

    2016-01-01

    Sandia National Laboratories has collaborated with Pleasanton Ridge Research Company (PRRC) to determine whether Sandia Octahedral Molecular Sieves (SOMS) and modified SOMs materials can be synthesized in large batches and produced in granular form. Sandia National Laboratories tested these SOMS and its variants based in aqueous chemical environments for an application-based evaluation of material performance as a sorbent. Testing focused primarily on determining the distribution coefficients (K d ) and chemical selectivity SOMs for alkali earth (Sr) ions in aqueous and dilute seawater solutions. In general the well-crystallized SOMS materials tested exhibited very high K d values (>10 6 ) in distilled water but K d values dropped substantially (%7E10 2 -10 3 ) in the dilute seawater (3%). However, one set of SOMS samples (1.4.2 and 1.4.6) provided by PRRC yielded relatively high K d (approaching 10 4 ) in dilute seawater. Further examination of these samples by scanning electron microscopy (SEM) revealed the presence of at least two phases at least one of which may be accounting for the improved K d values in dilute seawater. Evaluation of Strontium Selectivity by Sandia Octahedral Molecular Sieves (SOMS) January 20, 2016

  20. Udvidelsen af relationsfeltets didaktik – med religionsundervisningen som eksempel

    DEFF Research Database (Denmark)

    Skovmand, Keld

    beskrive denne dobbeltbevægelse som en almen fagdidaktik (Nielsen 1998 [1994]) eller – med inspiration fra Klafki – en relationsfeltets didaktik (Nielsen 2012). Dobbeltblikket på didaktikken som et relationsfelt kan kvalificeres ved hjælp af de fire kriterier for indholdsvalg, som er udformet af Frede V...... specificere indhold (DuFour & Marzano 2011). Referencer DuFour, Richard & Marzano, Robert J. 2011: Leaders of learning. How district, school, and classroom leaders improve student achievement. Bloomington, IN: Solution Tree Press. Hattie, John 2009: Visible learning. A synthesis of over 800 meta...

  1. Tv-serien som vor tids roman?

    DEFF Research Database (Denmark)

    Nielsen, Jakob Isak

    2012-01-01

    Artiklen gør rede for de forbindelseslinjer, der er mellem den nyere amerikanske tv-serie og en række andre udtryksformer (fx radiospillet og spillefilmen) for dernæst at fokusere på tv-seriens slægtskab med romanen. Alene i Danmark har såvel kulturjournalister som forskere påpeget ligheder de...... to udtryksformer imellem, og artiklen vil forsøge at skabe et overblik over berøringsfladerne og parallellerne. Artiklens tese er, at sammenligningen er gangbar i forhold til en række parametre – særligt hvis man indsnævrer de i udgangspunktet temmelig heterogene og vidtfavnende udtryksformer ”romanen” og ”tv......-serien” og fokuserer på bestemte eksempler og strømninger samt på bestemte distributions-, brugs- og oplevelsesformer (særligt DVD-udgivelsen ifm. tv-serier fx). Eksemplerne er primært fra en række nyere amerikanske tv-serier fra The Sopranos (HBO, 1999-2007) og frem, og artiklen vil afslutningsvist påpege...

  2. Time travel in the homogeneous Som-Raychaudhuri Universe

    International Nuclear Information System (INIS)

    Paiva, F.M.; Reboucas, M.J.; Teixeira, A.F.F.

    1987-01-01

    Properties of the rotating Som-Raychaudhuri homogeneous space-time are investigated: time-like and null geodesics, causality features, horizons and invariant characterization. An integral representation of its five isometries is also discussed. (author) [pt

  3. Organic matter and salinity modify cadmium soil (phyto)availability.

    Science.gov (United States)

    Filipović, Lana; Romić, Marija; Romić, Davor; Filipović, Vilim; Ondrašek, Gabrijel

    2018-01-01

    Although Cd availability depends on its total concentration in soil, it is ultimately defined by the processes which control its mobility, transformations and soil solution speciation. Cd mobility between different soil fractions can be significantly affected by certain pedovariables such as soil organic matter (SOM; over formation of metal-organic complexes) and/or soil salinity (over formation of metal-inorganic complexes). Phytoavailable Cd fraction may be described as the proportion of the available Cd in soil which is actually accessible by roots and available for plant uptake. Therefore, in a greenhouse pot experiment Cd availability was observed in the rhizosphere of faba bean exposed to different levels of SOM, NaCl salinity (50 and 100mM) and Cd contamination (5 and 10mgkg -1 ). Cd availability in soil does not linearly follow its total concentration. Still, increasing soil Cd concentration may lead to increased Cd phytoavailability if the proportion of Cd 2+ pool in soil solution is enhanced. Reduced Cd (phyto)availability by raised SOM was found, along with increased proportion of Cd-DOC complexes in soil solution. Data suggest decreased Cd soil (phyto)availability with the application of salts. NaCl salinity affected Cd speciation in soil solution by promoting the formation of CdCl n 2-n complexes. Results possibly suggest that increased Cd mobility in soil does not result in its increased availability if soil adsorption capacity for Cd has not been exceeded. Accordingly, chloro-complex possibly operated just as a Cd carrier between different soil fractions and resulted only in transfer between solid phases and not in increased (phyto)availability. Copyright © 2017 Elsevier Inc. All rights reserved.

  4. Organic matter turnover in subsoils: current knowledge and future challenges

    Science.gov (United States)

    Marschner, Bernd

    2014-05-01

    In the past, carbon flux measurements and modelling have mostly considered the topsoil where C-concentrations, root densities and microbial activities are generally highest. However, depending on climate zone and land use, this soil compartment contains only 30-50% of the C-stocks of the first meter. If the deeper subsoil down to 3 m is also considered, the contribution of topsoil carbon stocks to total soil C-pools is only 20-40%. Another distinct property of subsoil organic matter is its high apparent 14C age. The 14C age of bulk soil organic matter below 30 cm depth generally increases continuously indicating mean residence times of several 103 to 104 years. Large pool size and high radiocarbon age suggest that subsoil OM has accumulated at very low rates over very long time periods and therefore appears to be very stable. In this review, several hypotheses for explaining why subsoil SOM is so seemingly old and inert are presented. These questions are being addressed in a recently granted German research unit consisting of 9 subprojects from all soil science disciplines using field measurements of C-fluxes, 14C analyses and conducting field and lab experiments.

  5. Portræt af litteraturkritikeren som ungt menneske

    DEFF Research Database (Denmark)

    Schatz-Jakobsen, Claus

    2004-01-01

    Artiklen præsenterer den amerikanske litteraturkritiker Geoffrey Hartmans tidlige forfatterskab og fremdrager dets selvbiografiske undertekst som nødvendig effekt af den unge Hartmans fascination af den engelske romantiker William Wordsworths forfatterskab.......Artiklen præsenterer den amerikanske litteraturkritiker Geoffrey Hartmans tidlige forfatterskab og fremdrager dets selvbiografiske undertekst som nødvendig effekt af den unge Hartmans fascination af den engelske romantiker William Wordsworths forfatterskab....

  6. Ole Rømer som enevældens administrator

    DEFF Research Database (Denmark)

    Olden-Jørgensen, Sebastian

    2002-01-01

    En gennemgang af Ole Rømers liv med vægt på hans rolle som embedsmand og hans deltagelse eller mangel på samme i det politiske spil.......En gennemgang af Ole Rømers liv med vægt på hans rolle som embedsmand og hans deltagelse eller mangel på samme i det politiske spil....

  7. Identification of illicit drugs by using SOM neural networks

    Energy Technology Data Exchange (ETDEWEB)

    Liang Meiyan; Shen Jingling; Wang Guangqin [Beijing Key Lab for Terahertz Spectroscopy and Imaging, Key Laboratory of Terahertz Optoelectronics, Ministry of Education, Department of Physics, Capital Normal University, Beijing 100037 (China)], E-mail: liangyan661982@163.com, E-mail: jinglingshen@gmail.com, E-mail: pywgq2004@163.com

    2008-07-07

    Absorption spectra of six illicit drugs were measured by using the terahertz time-domain spectroscopy technique in the range 0.2-2.6 THz and then clustered with self-organization feature map (SOM) artificial neural network. After the network training process, the spectra collected at another time were identified successfully by the well-trained SOM network. An effective distance was introduced as a quantitative criterion to decide which cluster the new spectra were affiliated with.

  8. Brands som ideologiske parasitter

    DEFF Research Database (Denmark)

    Hermansen, Judy

    2009-01-01

    De store, stærke brands, som rager op over alle andre som repræsentanter for nogle værdier, der bliver lagt vægt på i samfundet, kalder Douglas Holt for ikoniske. Vi snakker Coca Cola, Nike, Apple ligaen. For at opnå en sådan status er brandingen nødt til at holde et vågent øje med tendenser og...

  9. Identification of illicit drugs by using SOM neural networks

    International Nuclear Information System (INIS)

    Liang Meiyan; Shen Jingling; Wang Guangqin

    2008-01-01

    Absorption spectra of six illicit drugs were measured by using the terahertz time-domain spectroscopy technique in the range 0.2-2.6 THz and then clustered with self-organization feature map (SOM) artificial neural network. After the network training process, the spectra collected at another time were identified successfully by the well-trained SOM network. An effective distance was introduced as a quantitative criterion to decide which cluster the new spectra were affiliated with

  10. Correlation between Soil Organic Matter, Total Organic Matter and ...

    African Journals Online (AJOL)

    A total of four sites distributed in different soils of Kelantan State, Malaysia was identified for the study. Soils were collected by depth interval of 0-10cm, 10-20cm and 20-30cm. The correlation of soil organic matter (SOM) content, total organic carbon (TOC) content, water content and soils texture for industrial area at ...

  11. Fate of lignin, cutin and suberin in soil organic matter fractions - an incubation experiment

    Science.gov (United States)

    Mueller, Carsten W.; Mueller, Kevin E.; Freeman, Katherine H.; Ingrid, Kögel-Knabner

    2010-05-01

    The turnover of soil organic matter (SOM) is controlled by its chemical composition, its spatial accessibility and the association with the mineral phase. Separation of bulk soils by physical fractionation and subsequent chemical analysis of these fractions should give insights to how compositional differences in SOM drive turnover rates of different size-defined carbon pools. The main objective of this study was to elucidate the relative abundance and recalcitrance of lignin, cutin and suberin in aggregated bulk soils and SOM fractions in the course of SOM decomposition. Bulk soils and physically-separated size fractions (sand, silt and clay) of the Ah horizon of a forest soil (under Picea abies L.Karst) were parallel incubated over a period of one year. In order to differentiate between particulate OM (POM) and mineral-associated SOM the particle size fractions were additionally separated by density after the incubation experiment. We used solid-state 13C-CPMAS NMR spectroscopy and GC-MS (after copper oxide oxidation and solvent extraction) to analyze the composition of the incubated samples. The abundance and isotopic composition (including 13C and 14C) of the respired CO2 further enabled us to monitor the dynamics of SOM mineralization. This approach allowed for differentiating between C stabilization of soil fractions due to accessibility/aggregation and to biochemical recalcitrance at different scales of resolution (GC-MS, NMR). We found a relative enrichment of alkyl C and decreasing lignin contents in the order of sand particulate OM (POM). For the fresh particulate OM (POM) of the sand fraction a clear decay of lignin was observed in the course of the incubation experiment, indicated by decreasing C/V and increasing ac/alV ratios. A relative decrease of aliphatic C in the incubated fractions compared to the incubated bulk soils showed the preferential mineralization of less recalcitrant C compounds that were spatially inaccessible in aggregates of the bulk

  12. Swimming pool cleaner poisoning

    Science.gov (United States)

    Swimming pool cleaner poisoning occurs when someone swallows this type of cleaner, touches it, or breathes in ... The harmful substances in swimming pool cleaner are: Bromine ... copper Chlorine Soda ash Sodium bicarbonate Various mild acids

  13. Swimming pool granuloma

    Science.gov (United States)

    ... this page: //medlineplus.gov/ency/article/001357.htm Swimming pool granuloma To use the sharing features on this page, please enable JavaScript. A swimming pool granuloma is a long-term (chronic) skin ...

  14. Fællesskab som fællesgørende bevægelse?

    DEFF Research Database (Denmark)

    Khawaja, Iram

    2014-01-01

    man kan tale om, og som noget, der konstant forhandles. 3. Fællesskab som situeret og forbundet med subjektivering 4. Fællesskab som hverken overindividuel eller subjektiv bevægelse og 5. Fællesskab som forbundet med belonging. Artiklen bevæger sig imellem teoretisk og empirisk analyse og inddrager et...... fokus på belonging som en central dimension i forståelsen af konstruktionen af fællesskaber....

  15. The forgotten part of carbon cycling: Organic matter storage and turnover in subsoils [SUBSOM

    Science.gov (United States)

    Marschner, B.

    2013-12-01

    In the past, carbon flux measurements and modelling have mostly considered the topsoil where C-concentrations, root densities and microbial activities are generally highest. However, depending on climate zone and land use, this soil compartment contains only 30-50% of the C-stocks of the first meter. If the deeper subsoil down to 3 m is also considered, the contribution of topsoil carbon stocks to total soil C-pools is only 20-40%. Another distinct property of subsoil organic matter is its high apparent 14C age. The 14C age of bulk soil organic matter below 30 cm depth generally increases continuously indicating mean residence times of several 103 to 104 years. Large pool size and high radiocarbon age suggest that subsoil OM has accumulated at very low rates over very long time periods and therefore appears to be very stable. In a review, several hypotheses for explaining why subsoil SOM is so seemingly old and inert are presented. Then a recently granted German research unit consisting of 9 subprojects from all soil science disciplines is introduced, which addresses these questions using field measurements of C-fluxes, 14C analyses and conducting field and lab experiments. 40-60% of soil C-pools are found below 40 cm depth (Data from Jobbagy & Jackson 2000).

  16. Programproduktion som Kritisk Teori – eller tv-teksten som industriel iscenesættelse

    Directory of Open Access Journals (Sweden)

    John Caldwell

    2003-09-01

    Full Text Available Denne artikel peger på nødvendigheden af en revurdering af den tre-delte model, som Fiske og Gripsrud har fremført, ved at vise, hvorledes ‘sekundære’ og ‘tertiære’ tv-tekster uafladeligt bevæger sig eller rejser hen imod en ‘primær’ tekstuel status i det amerikan- ske multikanals-»flow«. En detaljeret gennemgang af industriens tekstuelle praksis – programbegivenheder, network-branding, ka- nallogoer, filmene bag filmen, pressemateriale på video, salgsma- teriale og tilgrænsende digitale medier – viser hvorledes industrien teoretiserer sine egne vilkår direkte på skærmen, og dermed også hvordan publikum vejledes igennem en sådan offentlig cirkulation af »inside«-viden om tv-systemet. Artiklen er oversat af Henrik Bødker.

  17. Solar swimming pool

    Energy Technology Data Exchange (ETDEWEB)

    1985-01-01

    This report examines the feasibility of using solar collectors to heat the water in a previously unheated outdoor swimming pool. The solar system is used in conjunction with a pool blanket, to conserve heat when the pool is not in use. Energy losses through evaporation can be reduced by as much as 70% by a pool blanket. A total of 130 m{sup 2} of highly durable black synthetic collectors were installed on a support structure at a 30{degree} angle from the horizontal, oriented to the south. Circulation of pool water though the collectors, which is controlled by a differential thermostat, was done with the existing pool pump. Before installation the pool temperature averaged 16{degree}C; after installation it ranged from 20{degree} to 26{degree}C. It was hard to distinguish how much pool heating was due to the solar system and how much heat was retained by the pool blanket. However, the pool season was extended by five weeks and attendance tripled. 2 figs.

  18. Decoupling of lignin and total litter decomposition across North American forest soils: a phenomenon to reconcile old and new paradigms of soil organic matter?

    Science.gov (United States)

    Hall, S. J.; Hammel, K.

    2017-12-01

    An "old" paradigm of soil organic matter (SOM) posited that biochemically "recalcitrant" lignin derivatives were a dominant constituent. Over the past decade(s), evidence for a newer paradigm has emerged which suggests that recalcitrance has little long-term impact on the biochemical composition of SOM, and that lignin is relatively unimportant in comparison with dead microbial biomass. Yet, methodological biases have hampered accurate quantification of lignin dynamics in mineral soils, and may have led to systematic underestimates of lignin stocks and turnover. Here, we sought to test this aspect of the "new" SOM paradigm. Synthetic position-specific 13C-labeled lignins provide a robust quantitative method to track the mineralization and fate of lignin moieties in mineral soils. Relatively few microbial taxa are known to depolymerize macromolecular lignin, and lignin derivatives can specifically associate with iron oxide mineral phases. Consequently, we hypothesized that decomposition of lignin is poorly correlated with total litter decomposition across ecosystems, and that lignin may represent a variable but significant component of decadal-cycling SOM. We incubated 10 forest soils spanning diverse North American ecosystems over seven months under laboratory conditions at constant temperature and moisture. Soils were incubated alone, with added C4 grass litter and natural isotope abundance lignin, and with added C4 litter and 13Cß-labeled lignin. These treatments allowed us to partition respiration for each soil from SOM, litter, and the Cß moiety of lignin—which is diagnostic for cleavage of the polymer. Consistent with our hypothesis, we found much greater variability (ten-fold) in cumulative lignin mineralization relative to bulk litter (two-fold) among soils. Multiple-pool first-order decay models implied that mean turnover times for lignin ranged from one to several decades among soils, relative to several years for bulk litter. Our results suggest a

  19. Microbes Persist: Using a Systems Biology Approach to Reveal How the Soil Microbiome Shapes Soil Organic Matter

    Science.gov (United States)

    Pett-Ridge, J.

    2017-12-01

    Soils store more carbon than the atmosphere and terrestrial vegetation combined, yet the factors that control its persistence remain elusive. Recent insights have overturned the long-held assumption that carbon stability depends mostly on chemical `recalcitrance' of soil organic matter (SOM). Instead, an emerging paradigm emphasizes how environmental drivers like temperature and moisture, soil minerals, and microbial ecology interact to control SOM formation, stabilization, and turnover. Detailed spectroscopic and isotopic (14C) analyses of mineral-associated SOM show that the oldest carbon in soil may be easily broken down and respired in the laboratory, and that it biochemically resembles microbial cells and metabolites far more than plant material. This places microbial ecophysiology at the center of the soil carbon persistence question. Microbial cells likely interact with mineral surfaces as part of an ecological strategy to condition their environment (e.g. biofilm formation or extracellular enzyme production), and their diverse cellular components likely associate with minerals after cells die. Collectively, these microbial characteristics - metabolic activities, population growth strategies, and cellular biochemistry - can be thought of as `soil ecophysiological traits'. This presentation will explore potential traits that may be fruitful targets for studies evaluating the persistence and importance of microbial products as SOM precursors, and will highlight results showing that soil mineral type influences the microbial communities that colonize mineral surfaces, as well as the quantity and type of mineral-associated carbon that accumulates. I will propose a series of integrated approaches that used together can examine how genomic capacity and activities of soil microbiomes are shaped by edaphic conditions (moisture, temperature, redox regimes) and fundamentally affect the terrestrial soil C pool.

  20. Burning transformations: Fire history effects on organic matter processing from hillslopes to streams

    Science.gov (United States)

    Barnes, R. T.; Gilbertson, A.; Maxwell, K.

    2017-12-01

    Disturbance strongly regulates material and energy flows, changing ecosystem pattern and process. An increase in the size and severity of fire, particularly in the Intermountain West, over the last several decades is expected to continue due to a warming climate. Predicting how fire will alter the net ecosystem carbon balance requires us to understand how carbon is stored, processed, and transferred. Here we present results from paired watersheds focused on five 2002 severe fires in Colorado to examine how organic matter is processed along the hillslope and within the stream. Comparing soil samples and water extractable organic matter (WEOM) between burned and unburned sites illustrates the impact of fire: burned soils have 50% organic matter (OM) content as unburned soils, regardless of geomorphic position. While a smaller pool, soil OM (SOM) in burned sites is more susceptible to microbial degradation (pmineral rich, organic poor, portion of the soil. Interestingly, the systematic shifts in OM amounts and quality (as measured by SUVA, E2:E3, and fluorescence) within the terrestrial system in response to fire, are not seen in stream exports. As such, while there are significant relationships (p<0.05) between stream DOM quality, DOM bioavailability, and stream metabolism, burned watersheds are not exporting DOM that is more bioavailable. In addition, despite different terrestrial OM pools, burned and unburned watersheds export statistically similar amounts of DOM per unit area, suggesting that a larger fraction of OM is transferred from the terrestrial to aquatic ecosystem within fire affected landscapes.

  1. Strategies for chemically healthy public swimming pools

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht

    spreading of pathogens between swimmers because of its residual disinfection effect. In addition to potential contamination of pathogenic microorganisms, swimming pool water is polluted by organic matter deposited from the bathers such as saliva, urine, sweat, hair and personal care products. Since chlorine...... is a strong oxidant it oxidizes the organic matter in the pool water and forms disinfection byproducts (DBPs). More than 100 different DBPs have been identified. Some of these have been found to be genotoxic and may pose an increased cancer risk for the bathers. The aim of this thesis was to give an overview...... of the strategies which can be used to achieve microbiological safe water with low levels of DBPs to ensure healthy environment for bathers. There are different approaches to achieve healthy environment in public swimming pools which in this thesis are divided into three strategies: alternatives to chlorination...

  2. Swimming-pool piles

    International Nuclear Information System (INIS)

    Trioulaire, M.

    1959-01-01

    In France two swimming-pool piles, Melusine and Triton, have just been set in operation. The swimming-pool pile is the ideal research tool for neutron fluxes of the order of 10 13 . This type of pile can be of immediate interest to many research centres, but its cost must be reduced and a break with tradition should be observed in its design. It would be an advantage: - to bury the swimming-pool; - to reject the experimental channel; - to concentrate the cooling circuit in the swimming-pool; - to carry out all manipulations in the water; - to double the core. (author) [fr

  3. Mindfulness som smertehåndteringsredskab for kvinder med endometriose

    DEFF Research Database (Denmark)

    Jensen, Mette Kold; Vedsted-Hansen, Hanne; Hansen, Tia G. B.

    2011-01-01

    Endometriose er en kronisk underlivssygdom med smerter og en række afledte problemer, som ikke nødvendigvis kan behandles med lægelige tiltag. Artiklen argumenterer for, at en mindfulness-baseret tilgang med fokus på smertehåndtering kan anvendes til denne klientgruppe. I vestlig terapeutisk...... sammenhæng kan mindfulness karakteriseres som nærvær, observation og beskrivelse af sansninger uden vurdering eller reaktion. Mindfulness-træning har effekt mod andre typer stress og kroniske smerter, og artiklen opridser et koncept til anvendelse ved endometriose. Konceptet belyses med en case, hvor...

  4. Ole Rømer som enevældens administrator

    DEFF Research Database (Denmark)

    Olden-Jørgensen, Sebastian

    2004-01-01

    En biografisk skitse af Ole Rømers virke med vægt på hans rolle som embedsmand og rådgiver for Christian V. Hans virke analyseres på baggrund af en ny forståelse for den tidlige enevældes politiske kultur.......En biografisk skitse af Ole Rømers virke med vægt på hans rolle som embedsmand og rådgiver for Christian V. Hans virke analyseres på baggrund af en ny forståelse for den tidlige enevældes politiske kultur....

  5. Kongehuset som varemærke og nationalt symbol

    DEFF Research Database (Denmark)

    Ravn Sørensen, Anders

    2016-01-01

    Kongehuset er ikke bare et nationalt symbol. Det er også et varemærke, som der er al mulig grund til at beskytte og vogte nidkært over. Kronen har nemlig god brandmæssig værdi.......Kongehuset er ikke bare et nationalt symbol. Det er også et varemærke, som der er al mulig grund til at beskytte og vogte nidkært over. Kronen har nemlig god brandmæssig værdi....

  6. Differences in SOM decomposition and temperature sensitivity among soil aggregate size classes in a temperate grasslands.

    Directory of Open Access Journals (Sweden)

    Qing Wang

    Full Text Available The principle of enzyme kinetics suggests that the temperature sensitivity (Q10 of soil organic matter (SOM decomposition is inversely related to organic carbon (C quality, i.e., the C quality-temperature (CQT hypothesis. We tested this hypothesis by performing laboratory incubation experiments with bulk soil, macroaggregates (MA, 250-2000 μm, microaggregates (MI, 53-250 μm, and mineral fractions (MF, MF>bulk soil >MI(P <0.05. The Q10 values were highest for MA, followed (in decreasing order by bulk soil, MF, and MI. Similarly, the activation energies (Ea for MA, bulk soil, MF, and MI were 48.47, 33.26, 27.01, and 23.18 KJ mol-1, respectively. The observed significant negative correlations between Q10 and C quality index in bulk soil and soil aggregates (P<0.05 suggested that the CQT hypothesis is applicable to soil aggregates. Cumulative C emission differed significantly among aggregate size classes (P <0.0001, with the largest values occurring in MA (1101 μg g-1, followed by MF (976 μg g-1 and MI (879 μg g-1. These findings suggest that feedback from SOM decomposition in response to changing temperature is closely associated withsoil aggregation and highlights the complex responses of ecosystem C budgets to future warming scenarios.

  7. Spent fuel storage pool

    International Nuclear Information System (INIS)

    Murakami, Naoshi.

    1996-01-01

    Fences are disposed to a fuel exchange floor surrounding the upper surface of a fuel pool for preventing overflow of pool water. The fences comprise a plurality of flat boards arranged in parallel with each other in the longitudinal direction while being vertically inclined, and slits are disposed between the boards for looking down the pool. Further, the fences comprise wide boards and are constituted so as to be laid horizontally on the fuel exchange floor in a normal state and uprisen by means of the signals from an earthquake sensing device. Even if pool water is overflow from the fuel pool by the vibrations occurred upon earthquake and flown out to the floor of the fuel exchange floor, the overflow from the fuel exchange floor is prevented by the fences. An operator who monitors the fuel pool can observe the inside of the fuel pool through the slits formed to the fences during normal operation. The fences act as resistance against overflowing water upon occurrence of an earthquake thereby capable of reducing the overflowing amount of water due to the vibrations of pool water. The effect of preventing overflowing water can be enhanced. (N.H.)

  8. Collaborative Car Pooling System

    OpenAIRE

    João Ferreira; Paulo Trigo; Porfírio Filipe

    2009-01-01

    This paper describes the architecture for a collaborative Car Pooling System based on a credits mechanism to motivate the cooperation among users. Users can spend the accumulated credits on parking facilities. For this, we propose a business model to support the collaboration between a car pooling system and parking facilities. The Portuguese Lisbon-s Metropolitan area is used as application scenario.

  9. Dinner in the dark: Illuminating drivers of soil organic matter decomposition

    NARCIS (Netherlands)

    van der Wal, Annemieke; De Boer, Wietse

    Abstract Soil organic matter (SOM) dynamics plays a crucial role in soil ecosystem functioning and global warming. SOM is normally degraded slowly, but its decomposition rate can change substantially after addition of easily decomposable C sources. This process, known as “the priming effect”, has

  10. Mycorrhizal hyphal turnover as a dominant process for carbon input into soil organic matter

    NARCIS (Netherlands)

    Godbold, D.; Hoosbeek, M.R.; Lukac, M.; Francesca Cotrufo, M.; Janssens, I.A.; Ceulemans, R.; Polle, A.; Velthorst, E.J.; Scarascia-Mugnozza, G.; Angelis, de P.; Miglietta, F.; Peressotti, A.

    2006-01-01

    The atmospheric concentration of CO2 is predicted to reach double current levels by 2075. Detritus from aboveground and belowground plant parts constitutes the primary source of C for soil organic matter (SOM), and accumulation of SOM in forests may provide a significant mechanism to mitigate

  11. Modeling the vertical soil organic matter profile using Bayesian parameter estimation

    NARCIS (Netherlands)

    Braakhekke, M.C.; Wutzler, T.; Beer, C.; Kattge, J.; Schrumpf, M.; Schöning, I.; Hoosbeek, M.R.; Kruijt, B.; Kabat, P.

    2012-01-01

    The vertical distribution of soil organic matter (SOM) in the profile may constitute a significant factor for soil carbon cycling. However, the formation of the SOM profile is currently poorly understood due to equifinality, caused by the entanglement of several processes: input from roots, mixing

  12. Modeling the vertical soil organic matter profile using Bayesian parameter estimation

    NARCIS (Netherlands)

    Braakhekke, M.C.; Wutzler, T.; Beer, C.; Kattge, J.; Schrumpf, M.; Ahrens, B.; Schoning, I.; Hoosbeek, M.R.; Kruijt, B.; Kabat, P.; Reichstein, M.

    2013-01-01

    The vertical distribution of soil organic matter (SOM) in the profile may constitute an important factor for soil carbon cycling. However, the formation of the SOM profile is currently poorly understood due to equifinality, caused by the entanglement of several processes: input from roots, mixing

  13. Soil organic matter dynamics after the conversion of arable land to pasture

    NARCIS (Netherlands)

    Römkens, P.F.A.M.; Plicht, van der J.; Hassink, J.

    1999-01-01

    Conversion of arable land (maize) to pasture will affect the soil organic matter (SOM) content. Changes in the SOM content were studied using a size- and density-fractionation method and 13C analysis. Twenty-six years of maize cropping had resulted in a depletion of carbon stored in the

  14. Temperature sensitivity (Q10), and dynamics of soil organic matter (SOM) decomposition in permafrost soils with different carbon quality and under experimental warming. R. Bracho1, E.A.G Schuur1, E. Pegoraro1, K.G. Crummer1, S. Natali2, J. Zhou, Y Luo3, J. L. Wu3, M. Tiedje4, K. Konstantinidis5 1Department of Biology, University of Florida, Gainesville, FL. 2Woods Hole Research Center, Falmouth, MA. 3Institute for Environmental Genomics and Department of Botany and Microbiology, University of Oklahoma, Norman, OK, 4Center for Microbial Ecology, Michigan State University, East Lansing, MI; 5Center for Bioinformatics and Computational Genomics and School of Biology, Georgia Institute of Technology, Atlanta, GA

    Science.gov (United States)

    Bracho, R. G.; Schuur, E. A.; Pegoraro, E.; Crummer, K. G.; Natali, S.; Zhou, J.; Wu, L.; Luo, Y.; Tiedje, J. M.; Konstantinidis, K.

    2013-12-01

    Permafrost soils contain approximately1700 Pg of carbon (C), twice the amount of C in the atmosphere. Temperatures in higher latitudes are increasing, inducing permafrost thaw and subsequent microbial decomposition of previously frozen C. This process is one of the most likely positive feedbacks to climate change. Understanding the temperature sensitivity (Q10) and dynamics of SOM decomposition under warming is essential to predict the future state of the earth - climate system. Alaskan tundra soils were exposed to two winter warming (WW) seasons in the field, which warmed the soils by 4°C to 40 cm depth. Soils were obtained from three depths (0 - 15, 15 - 25 and 45 - 55 cm) and differed in initial amounts of labile and recalcitrant C. Soils were incubated in the lab under aerobic conditions, at 15 and 25°C over 365 days. Q10 was estimated at 14, 100 & 280 days of incubation (DOI); C fluxes were measured periodically and dynamics of SOM decomposition (C pool sizes and decay rates) were estimated by fitting a two pool C model to cumulative respired C (Ccum, mgC/ginitialC). After two WW seasons, initial C content tended to decrease through the soil profile and C:N ratio was significantly decreased in the top 15 cm. After one year of incubation, Ccum was twice as high at 25°C as at 15°C and significantly decreased with depth. No significant WW field treatment was detected, although Ccum tended to be lower in warmed soils. Labile C accounted for up to 5% of initial soil C content in the top 15 cm and decreased with depth. Soils exposed to WW had smaller labile C pools, and higher labile C decay rates in the top 25 cm. Q10 significantly decreased with time and depth as labile pool decreased, especially for WW. This decrease with time indicates a lower temperature sensitivity of the most recalcitrant C pool. The deepest WW soil layer, where warming was more pronounced, had significantly lower Q10 compared to control soils at the same depth. After two seasons, the

  15. Dynamics of soil organic matter in primary and secondary forest succession on sandy soils in The Netherlands: An application of the ROMUL model

    NARCIS (Netherlands)

    Nadporozhskaya, M.A.; Mohren, G.M.J.; Chertov, O.G.; Komarov, A.S.; Mikhailov, A.V.

    2006-01-01

    We applied the simulation model ROMUL of soil organic matter dynamics in order to analyse and predict forest soil organic matter (SOM) changes following stand growth and also to identify gaps of data and modelling problems. SOM build-up was analysed (a) from bare sand to forest soil during a primary

  16. Digital portfolio som metode og pædagogik

    DEFF Research Database (Denmark)

    Toft, Hanne; Luplau Schnefeld, Mette

    2004-01-01

    Artiklen præsenterer erfaringer med digital portfolio som didaktik og metode. Fokus er på kobling mellem didaktiske læreprocesser på en grunduddannelse og så understøttelse af disse via brug af en digital portfolio. Portfolioen adskiller en række forskellige dokumentsamlinger i privat og offentlig...

  17. Rushdie som symbol på blasfemi mod islam

    DEFF Research Database (Denmark)

    Jacobsen, Brian Arly

    2012-01-01

    Vil man forstå dødsdommen over Rushdie, skal man forstå billederne om Iran, der er konstrueret af Rushdie i De Sataniske Vers. Det handler om Rushdies brug af forskellige narrativer, eksempelvis brugen af begrebet 'Jahilia', som er velkendt af alle muslimer, der anvendes til at karakterisere Mekk...

  18. Sansning som redskab og metode for faget Modedesign

    DEFF Research Database (Denmark)

    Ræbild, Ulla

    2009-01-01

      Abstract / dansk Intentionen i denne afhandling er at undersøge, hvornår og hvordan designere anvender sansemæssig viden og kompetence i deres arbejdsproces, for igennem denne afdækning at kunne foretage en eksplicitering og artikulation af sansning som redskab og metode i designprocessen. Afha...

  19. Læring som improviseret udvikling af praksis

    DEFF Research Database (Denmark)

    Brinck, Lars

    2010-01-01

    Med afsæt i forfatterens fænomenografiske studie af amerikanske musikeres oplevelse af det at jamme diskuterer artiklen, hvorvidt jam-bandets spontant improviserende praksis kan give ny forståelse af rytmiske musikeres læring som et overordnet socialt fænomen. Ved at betragte jam-bandets praksis i...

  20. Feedback i professionsuddannelsen som pædagog

    DEFF Research Database (Denmark)

    Rold, Mette; Bjørnshave, Inge Andrea

    2015-01-01

    Feedback som begreb er her og nu kommet i søgelyset på de videregående uddannelser, fordi mange studerende, blandt andet i medierne, tilkendegiver at de ikke modtager nok feedback i forhold til den undervisning, de modtager. Dette paper er udgangspunkt for en fælles diskussion om netop dette....

  1. Content Management som platform og pædagogisk strategi

    DEFF Research Database (Denmark)

    Petersen, Kim Bach; Rasmussen, Steen Cnops

    2005-01-01

    Med afsæt i konkrete erfaringer på pædagoguddannelsen argumenteres der for, at implementeringen af it-systemer og udviklingen af de ansattes it-kompetencer bør tage afsæt i en pædagogisk tænkning, som prioriterer enkelthed og brugervenlighed højt....

  2. Socialpædagogik iagttaget som et socialt praksisfelt

    DEFF Research Database (Denmark)

    Hansen, Janne Hedegaard

    2013-01-01

    Ved at iagttage socialpædagogers situerede handlinger i praksis er det muligt at opnå viden om de forståelser, socialpædagoger handler på grundlag af, og som sætter betingelser for brugernes handle- og livsmuligheder. Men brugerne er ikke blot underlagt socialpædagogers betydningskonstruktioner...

  3. Pave Benedikt XVI som social kritiker og moderniseringsteoretiker

    DEFF Research Database (Denmark)

    Thomassen, Bjørn

    2013-01-01

    former for kritik af det moderne projekt, en kritik som deler mange lighedspunkter med Frankfurterskolen. Disse ligheder kom blandt andet til syne i Kardinal Ratzingers berømte debat med Habermas, men ligeledes i nogle af hans seneste skrifter, især hans meget omtalte tredje encyklik, Caritas in Veritate...

  4. Soil texture analysis revisited: Removal of organic matter matters more than ever

    Science.gov (United States)

    Schjønning, Per; Watts, Christopher W.; Christensen, Bent T.; Munkholm, Lars J.

    2017-01-01

    Exact estimates of soil clay (<2 μm) and silt (2–20 μm) contents are crucial as these size fractions impact key soil functions, and as pedotransfer concepts based on clay and silt contents are becoming increasingly abundant. We examined the effect of removing soil organic matter (SOM) by H2O2 before soil dispersion and determination of clay and silt. Soil samples with gradients in SOM were retrieved from three long-term field experiments each with uniform soil mineralogy and texture. For soils with less than 2 g C 100 g-1 minerals, clay estimates were little affected by SOM. Above this threshold, underestimation of clay increased dramatically with increasing SOM content. Silt contents were systematically overestimated when SOM was not removed; no lower SOM threshold was found for silt, but the overestimation was more pronounced for finer textured soils. When exact estimates of soil particles <20 μm are needed, SOM should always be removed before soil dispersion. PMID:28542416

  5. 13 CFR 120.611 - Pools backing Pool Certificates.

    Science.gov (United States)

    2010-01-01

    ... 13 Business Credit and Assistance 1 2010-01-01 2010-01-01 false Pools backing Pool Certificates. 120.611 Section 120.611 Business Credit and Assistance SMALL BUSINESS ADMINISTRATION BUSINESS LOANS Secondary Market Certificates § 120.611 Pools backing Pool Certificates. (a) Pool characteristics. As set...

  6. Linking temperature sensitivity of soil organic matter decomposition to its molecular structure, accessibility, and microbial physiology.

    Science.gov (United States)

    Wagai, Rota; Kishimoto-Mo, Ayaka W; Yonemura, Seiichiro; Shirato, Yasuhito; Hiradate, Syuntaro; Yagasaki, Yasumi

    2013-04-01

    Temperature sensitivity of soil organic matter (SOM) decomposition may have a significant impact on global warming. Enzyme-kinetic hypothesis suggests that decomposition of low-quality substrate (recalcitrant molecular structure) requires higher activation energy and thus has greater temperature sensitivity than that of high-quality, labile substrate. Supporting evidence, however, relies largely on indirect indices of substrate quality. Furthermore, the enzyme-substrate reactions that drive decomposition may be regulated by microbial physiology and/or constrained by protective effects of soil mineral matrix. We thus tested the kinetic hypothesis by directly assessing the carbon molecular structure of low-density fraction (LF) which represents readily accessible, mineral-free SOM pool. Using five mineral soil samples of contrasting SOM concentrations, we conducted 30-days incubations (15, 25, and 35 °C) to measure microbial respiration and quantified easily soluble C as well as microbial biomass C pools before and after the incubations. Carbon structure of LFs (soil was measured by solid-state (13) C-NMR. Decomposition Q10 was significantly correlated with the abundance of aromatic plus alkyl-C relative to O-alkyl-C groups in LFs but not in bulk soil fraction or with the indirect C quality indices based on microbial respiration or biomass. The warming did not significantly change the concentration of biomass C or the three types of soluble C despite two- to three-fold increase in respiration. Thus, enhanced microbial maintenance respiration (reduced C-use efficiency) especially in the soils rich in recalcitrant LF might lead to the apparent equilibrium between SOM solubilization and microbial C uptake. Our results showed physical fractionation coupled with direct assessment of molecular structure as an effective approach and supported the enzyme-kinetic interpretation of widely observed C quality-temperature relationship for short-term decomposition. Factors

  7. PDA: Pooled DNA analyzer

    Directory of Open Access Journals (Sweden)

    Lin Chin-Yu

    2006-04-01

    Full Text Available Abstract Background Association mapping using abundant single nucleotide polymorphisms is a powerful tool for identifying disease susceptibility genes for complex traits and exploring possible genetic diversity. Genotyping large numbers of SNPs individually is performed routinely but is cost prohibitive for large-scale genetic studies. DNA pooling is a reliable and cost-saving alternative genotyping method. However, no software has been developed for complete pooled-DNA analyses, including data standardization, allele frequency estimation, and single/multipoint DNA pooling association tests. This motivated the development of the software, 'PDA' (Pooled DNA Analyzer, to analyze pooled DNA data. Results We develop the software, PDA, for the analysis of pooled-DNA data. PDA is originally implemented with the MATLAB® language, but it can also be executed on a Windows system without installing the MATLAB®. PDA provides estimates of the coefficient of preferential amplification and allele frequency. PDA considers an extended single-point association test, which can compare allele frequencies between two DNA pools constructed under different experimental conditions. Moreover, PDA also provides novel chromosome-wide multipoint association tests based on p-value combinations and a sliding-window concept. This new multipoint testing procedure overcomes a computational bottleneck of conventional haplotype-oriented multipoint methods in DNA pooling analyses and can handle data sets having a large pool size and/or large numbers of polymorphic markers. All of the PDA functions are illustrated in the four bona fide examples. Conclusion PDA is simple to operate and does not require that users have a strong statistical background. The software is available at http://www.ibms.sinica.edu.tw/%7Ecsjfann/first%20flow/pda.htm.

  8. Corporate film som værktøj til employer branding

    DEFF Research Database (Denmark)

    Hansen, Heidi

    2016-01-01

    En corporate film kan ses som organisationens autoritative tekst kommunikeret i en enkelt digital fortælling. I denne artikel belyses corporate film som genre fra henholdsvis kommunikationsdirektørens, forskerens, det kreative bureau og filmskaberens side.......En corporate film kan ses som organisationens autoritative tekst kommunikeret i en enkelt digital fortælling. I denne artikel belyses corporate film som genre fra henholdsvis kommunikationsdirektørens, forskerens, det kreative bureau og filmskaberens side....

  9. Networking our science to characterize the state, vulnerabilities, and management opportunities of soil organic matter

    Science.gov (United States)

    Harden, Jennifer W.; Hugelius, Gustaf; Ahlström, Anders; Blankinship, Joseph C.; Bond-Lamberty, Ben; Lawrence, Corey; Loisel, Julie; Malhotra, Avni; Jackson, Robert B.; Ogle, Stephen M.; Phillips, Claire; Ryals, Rebecca; Todd-Brown, Katherine; Vargas, Rodrigo; Vergara, Sintana E.; Cotrufo, M. Francesca; Keiluweit, Marco; Heckman, Katherine; Crow, Susan E.; Silver, Whendee L.; DeLonge, Marcia; Nave, Lucas E.

    2018-01-01

    Soil organic matter (SOM) supports the Earth's ability to sustain terrestrial ecosystems, provide food and fiber, and retains the largest pool of actively cycling carbon. Over 75% of the soil organic carbon (SOC) in the top meter of soil is directly affected by human land use. Large land areas have lost SOC as a result of land use practices, yet there are compensatory opportunities to enhance productivity and SOC storage in degraded lands through improved management practices. Large areas with and without intentional management are also being subjected to rapid changes in climate, making many SOC stocks vulnerable to losses by decomposition or disturbance. In order to quantify potential SOC losses or sequestration at field, regional, and global scales, measurements for detecting changes in SOC are needed. Such measurements and soil-management best practices should be based on well established and emerging scientific understanding of processes of C stabilization and destabilization over various timescales, soil types, and spatial scales. As newly engaged members of the International Soil Carbon Network, we have identified gaps in data, modeling, and communication that underscore the need for an open, shared network to frame and guide the study of SOM and SOC and their management for sustained production and climate regulation.

  10. The second wave of earthworm invasion: soil organic matter dynamics from the stable isotope perspective

    Science.gov (United States)

    Chang, C.; Szlavecz, K. A.; Bernard, M.; Pitz, S.

    2013-12-01

    Through transformation of plant litter into soil organic matter (SOM) and translocation of ingested organic material among different soil depths, soil organisms, especially earthworms, are one of the major factors affecting SOM dynamics. In North America temperate soil, historical human activity has lead to invasion of European earthworms into habitats that were previously earthworm-free or inhabited only by native species. By consuming leaf litter and SOM, burrowing, and casting, invasive earthworms have been known for reducing the understory vegetation and leaf litter layer while increasing the thickness of organic soil, causing changes in the soil habitat and the distribution of SOM. Recently, another group of invasive earthworm, namely Amynthas from Asia, has been reported invading habitats already dominated by European species, causing a 'second wave of invasion' where the soil ecosystem, already modified by European species, is going through another transition. The mechanisms through which these functionally (ecologically) different species affect C and N transformation could be better understood by tracing the carbon and nitrogen derived from 13C- and 15N-labeled leaf litter into earthworm tissues and SOM. The objective of this study is to understand how earthworm species that differ ecologically, including the Asian Amynthas, interact with each other and how these interactions affect SOM dynamics. We hypothesized that 1) species feeding on different food resources will have different isotopic signature and their tissue 13C and 15N values will change due to facilitation or interspecific competition on food resources, and 2) the short-term fate of litter-derived carbon differs depending on the presence or absence of different earthworm species. These hypotheses were tested by field sampling and lab mesocosm experiments using 13C and 15N double-enriched Tulip Poplar leaf litter (mean 13C = 124‰, mean 15N = 1667‰) produced from tree saplings growing in an

  11. Swimming Pool Safety

    Science.gov (United States)

    ... Spread the Word Shop AAP Find a Pediatrician Safety & Prevention Immunizations All Around At Home At Play ... Español Text Size Email Print Share Swimming Pool Safety Page Content ​What is the best way to ...

  12. Vitamin D Pooling Project

    Science.gov (United States)

    The Vitamin D Pooling Project of Rarer Cancers brought together investigators from 10 cohorts to conduct a large prospective epidemiologic study of the association between vitamin D status and seven rarer cancers.

  13. Swimming pool special; Zwembadspecial

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2010-05-15

    This issue includes a few articles and messages on the use of heat pump systems in swimming pools. [Dutch] Dit nummer bevat onder meer een paar artikelen over het gebruik van warmtepompsystemen in zwembaden.

  14. Towards a molecular level understanding of the sulfanilamide-soil organic matter-interaction

    Energy Technology Data Exchange (ETDEWEB)

    Ahmed, Ashour A., E-mail: ashour.ahmed@uni-rostock.de [University of Rostock, Institute of Physics, Albert-Einstein-Str. 23-24, D-18059 Rostock (Germany); Steinbeis GmbH & Co. KG für Technologietransfer, 70174 Stuttgart (Germany); University of Cairo, Faculty of Science, Department of Chemistry, 12613 Giza (Egypt); Thiele-Bruhn, Sören, E-mail: thiele@uni-trier.de [University of Trier, Soil Science, D-54286 Trier (Germany); Leinweber, Peter, E-mail: peter.leinweber@uni-rostock.de [Steinbeis GmbH & Co. KG für Technologietransfer, 70174 Stuttgart (Germany); University of Rostock, Soil Science, D-18051 Rostock (Germany); Kühn, Oliver, E-mail: oliver.kuehn@uni-rostock.de [University of Rostock, Institute of Physics, Albert-Einstein-Str. 23-24, D-18059 Rostock (Germany)

    2016-07-15

    Sorption experiments of sulfanilamide (SAA) on well-characterized samples of soil size-fractions were combined with the modeling of SAA-soil-interaction via quantum chemical calculations. Freundlich unit capacities were determined in batch experiments and it was found that they increase with the soil organic matter (SOM) content according to the order fine silt > medium silt > clay > whole soil > coarse silt > sand. The calculated binding energies for mass-spectrometrically quantified sorption sites followed the order ionic species > peptides > carbohydrates > phenols and lignin monomers > lignin dimers > heterocyclic compounds > fatty acids > sterols > aromatic compounds > lipids, alkanes, and alkenes. SAA forms H-bonds through its polar centers with the polar SOM sorption sites. In contrast dispersion and π-π-interactions predominate the interaction of the SAA aromatic ring with the non-polar moieties of SOM. Moreover, the dipole moment, partial atomic charges, and molecular volume of the SOM sorption sites are the main physical properties controlling the SAA-SOM-interaction. Further, reasonable estimates of the Freundlich unit capacities from the calculated binding energies have been established. Consequently, we suggest using this approach in forthcoming studies to disclose the interactions of a wide range of organic pollutants with SOM. - Highlights: • Experiment and theory showed that SAA obeys a site-specific sorption on soil surfaces. • SAA-SOM-interaction increases by increasing polarity of SOM sorption site. • H-bonds, dispersion, and π-π-interactions were observed for SAA-SOM-interaction. • Dipole moment and atomic charges of SOM sorption sites control SAA-SOM-interaction. • The Freundlich unit capacities were estimated from the calculated binding energies. • The current SOM model is flexible to describe interactions of SOM with other pollutants.

  15. Assessment of carbon pools in two soils from the Campania region (Southwest, Italy) under different forest types

    Science.gov (United States)

    Álvarez-Romero, Marta; Papa, Stefania; Lozano-García, Beatriz; Parras-Alcántara, Luis; González-Pérez, José A.; Jordán, Antonio; Zavala, Lorena M.; González-Vila, Francisco J.; Coppola, Elio

    2014-05-01

    Soil is the largest carbon reservoir of terrestrial ecosystems, this reservoir is not inert, but it is constantly in a dynamic phase of accumulation an depletion. After the addition, in the soil, of organic residues of different origin and nature, two processes can occur in charge of SOM (Soil Organic Matter) during the pedogenesis: mineralization and humification. The accumulation of SOM in soil is controlled by the balance between carbon inputs and losses through mineralization and/or leaching. In particular the humification process leads to the formation of organic compounds (in some cases even complex organo-mineral) chemically stable able to distribute itself in the soil second rules of site-specific pedogenesis. The transport process along the profile can take very different forms which may extend in the formation of Bh horizons of accumulation in depth also strongly cemented (so-called ortstein). The transport process along the profile occurs for the occurrence of certain conditions such as deposition of high amounts of organic residues on the top of the profile, high porosity of the soil for the presence of coarse solid fractions (coarse sands or skeleton) that determinate a strong infiltrating capacity of the circulating waters, extreme temperatures can slow or stop the process of mineralization and/or humification in one intermediate step of the degradation process releasing organic metabolites with high or medium solubility and high loads of percolating water related to intense rainfall. The nature of the forest cover influence the quantity and quality of the organic materials deposited with marked differences between coniferous and deciduous especially in relation to resistance to degradation and production of intermediate metabolites. Two soils from Campania region located in Monte Santa Croce (Caserta, Italy) with andic properties, different forest cover (pine and chestnut) and that meets the requirements of the place and pedological formation

  16. «Halvdød av frost, men levende og beredt». Speiderbevegelsen som disiplineringsprosjekt

    OpenAIRE

    Schaanning, Espen

    2013-01-01

    I det som gjerne betegnes som speidernes Bibel, Scouting for Boys (1908), løftet speiderbevegelsens grunnlegger, Robert Baden-Powell (1857–1941), fram personer som alle speidergutter burde ha som forbilder. Et slikt forbilde beskrives slik: «Den romerske soldaten fra gamle dager, som ble stående på sin post da Pompeii ble begravd av lava og aske fra vulkanen Vesuv, viste lojalitet mot sin plikt. De har funnet liket hans og kan se hvordan han holdt hånden foran munn og nese for ikke å bli kval...

  17. Musik som værk og handling

    DEFF Research Database (Denmark)

    Vandsø, Anette

    Denne bog handler om den nye musik som både har værkkarakter men også en udpræget handlingskarakter. Her sys på symaskiner og smadres violiner, men hvad gør det ved værkkarakteren? ved værkanalysen ? og ved 'musikken'? På baggrund af disse spørgsmål tilbyder bogen en grundlagsteoretisk gentænkning...

  18. Den Pædagogiske Refleksionsmodel som sammenhængskraft

    DEFF Research Database (Denmark)

    Voergaard Poulsen, Bettina; Lucht, Camill; Vibholm Persson, Stine

    Den Pædagogiske Refleksions Model (PRM) illustrerer de vidensdimensioner, der indgår i en kvalificeret klinisk beslutning. I projektet 'Sammenhæng på TVÆRS i fremtidens sygeplejeuddannelse (PÅ TVÆRS)" indgår PRM som pædagogisk greb. Der undersøges om PRM skaber sammenhæng for studerendes læring i...

  19. Som Energia: sostenibilitat energètica i cooperativisme

    OpenAIRE

    Duran i Grant, Alexandre; Huijink, Gijsbert; Roselló, Marc

    2013-01-01

    La cooperativa Som Energia és una organització innovadora en el sector energètic a casa nostra. Proposa una forma de fer diferent de la de les empreses tradicionals del sector: ven energia renovable certificada, no té ànim de lucre i busca el bé comú. La proposta treballa per la sostenibilitat energètica.

  20. Studiemiljøundersøgelse som empowerment

    DEFF Research Database (Denmark)

    Keller, Hanne Dauer; Jensen, Annie Aarup

    2012-01-01

    Artiklen fokuserer på det metodemæssige i at arbejde med studiemiljø og studiemiljøundersøgelser i en kvalitativ, procesorienteret form, der står i kontrast til de traditionelle kvantitative metoder. En alternativ organisering med de studerende som ansvarlige aktører gav andre, mere nuancerede da...... datatyper og aktiverede de studerende i forhold til at påvirke eget studiemiljø....

  1. Sociale teknologier og web 2.0 som vidensmedier

    DEFF Research Database (Denmark)

    Johannsen, Carl Gustav

    2011-01-01

    Artiklen fokuserer på effekten af brugen af sociale teknologier i folkebibliotekerne med fokus på i hvilken udstrækning de sociale teknologier lader sig forstå og analysere som vidensmedier, kommunikationsmønstre ved brug af sociale medier, de sociale mediers virkninger i undervisningssammenhænge...... og endelig de kulturpolitiske konsekvenser af bibliotekernes inddragelse af sociale teknologier....

  2. Specialestuderendes læringsudfordringer i vejledningen - nudging som handlemulighed

    DEFF Research Database (Denmark)

    Jensen, Hanne Nexø; Juul Jensen, Christina

    2015-01-01

    teoretiske afsæt er generiske læringsudfordringer i vejledningsprocesser, hvor læring opstår, når de studerende passerer en læringsudfordring. Vejledere kan bruge forståelsen af læringsudfordringer til at ”nudge”- plante en idé – som en måde at få studerende til at passere læringsudfordringerne....

  3. Feedback som indgang til læringsprocessen

    DEFF Research Database (Denmark)

    Kirkegaard, Preben Olund

    2017-01-01

    Feedback har til formål at forbedre dine studerendes færdigheder i et fag. Feedback skal tage udgangspunkt i den studerendes nuværende færdigheder og inkludere anvisninger på, hvordan den studerende fremadrettet kan arbejde for at opfylde et ønsket læringsmål. Måden hvorpå du som underviser...

  4. Betyder modellering det samme i naturfag som i matematik?

    DEFF Research Database (Denmark)

    Ejersbo, Lisser Rye

    2014-01-01

    Med de nye målformuleringer og læseplaner bruges udtrykket modellering nu både indenfor naturfag og matematik. Matematiklærere, som er vant til at arbejde med modellering tror måske, at det betyder det samme begge steder, men det behøver slet ikke at være tilfældet. Måske vi trænger til en...

  5. Technology Marketing using PCA , SOM, and STP Strategy Modeling

    OpenAIRE

    Sunghae Jun

    2011-01-01

    Technology marketing is a total processing about identifying and meeting the technological needs of human society. Most technology results exist in intellectual properties like patents. In our research, we consider patent document as a technology. So patent data are analyzed by Principal Component Analysis (PCA) and Self Organizing Map (SOM) for STP(Segmentation, Targeting, and Positioning) strategy modeling. STP is a popular approach for developing marketing strategies. We use STP strategy m...

  6. Age heterogeneity of soil organic matter

    International Nuclear Information System (INIS)

    Rethemeyer, J.; Grootes, P.M.; Bruhn, F.; Andersen, N.; Nadeau, M.J.; Kramer, C.; Gleixner, G.

    2004-01-01

    Accelerator mass spectrometry (AMS) radiocarbon measurements were used to investigate the heterogeneity of organic matter in soils of agricultural long-term trial sites in Germany and Great Britain. The strong age heterogeneity of the soil organic matter (SOM) is reflected by highly variable 14 C values of different organic components, ranging from modern (>100 pMC) to 7% modern carbon (pMC). At the field experiment in Halle (Germany), located in a heavily industrialized area, an increase of 14 C content with increasing depth was observed even though the input of modern plant debris should be highest in the topsoil. This is attributed to a significant contribution of old carbon (of up to 50% in the topsoil) to SOM. As a test to exclude the old carbon contamination, more specific SOM fractions were extracted. However, even a phospholipid fraction representing viable microbial biomass that is supposed to be short-lived in SOM, shows a strong influence of old, refractory carbon, when radiocarbon dated. In contrast, 14 C data of other field trials distant from industrial areas indicate that there inputs of old carbon to the soil are lower or even absent. Such locations are more favorable to study SOM stabilization and to quantify turnover of organic carbon in soils

  7. Sources of plant-derived carbon and stability of organic matter in soil: Implications for global change

    Science.gov (United States)

    Susan E. Crow; Kate Lajtha; Timothy R. Filley; Chris Swanston; Richard D. Bowden; Bruce A. Caldwell

    2009-01-01

    Alterations in forest productivity and changes in the relative proportion of above- and belowground biomass may have nonlinear effects on soil organic matter (SOM) storage. To study the influence of plant litter inputs on SOM accumulation, the Detritus Input Removal and Transfer (DIRT) Experiment continuously alters above- and belowground plant inputs to soil by a...

  8. Pool water cleaning facility

    Energy Technology Data Exchange (ETDEWEB)

    Yoshikawa, Kazuhiro; Kinoshita, Shoichiro [Hitachi Ltd., Tokyo (Japan); Asano, Takashi

    1998-05-29

    Only one system comprising a suppression poor water cleaning system (SPCU) and a filtration desalting tower (F/D) is connected for a plurality of nuclear power plants. Pipelines/valves for connecting the one system of the SPCU pump, the F/D and the plurality of nuclear power plants are disposed, and the system is used in common with the plurality of nuclear power plants. Pipelines/valves for connecting a pipeline for passing SP water to the commonly used SPCU pump and a skimmer surge tank are disposed, and fuel pool water is cooled and cleaned by the commonly used SPCU pump and the commonly used F/D. The number of SPCU pumps and the F/D facilities can be reduced, and a fuel pool water cooling operation mode and a fuel pool water cleaning operation mode which were conducted by an FPC pump so far are conducted by the SPCU pump. (N.H.)

  9. Income pooling within families

    DEFF Research Database (Denmark)

    Bonke, Jens; Uldall-Poulsen, Hans

    This paper analyses the phenomenon of income-pooling by applying the Danish household expenditure survey, merged with authoritative register information. Responses to additional questions on income sharing among 1696 couples also allows us to analyses whether the intra-household distribution...

  10. The influence of soluble organic matter on shale reservoir characterization

    Directory of Open Access Journals (Sweden)

    Lei Pan

    2016-06-01

    Full Text Available Shale with a maturity within the “oil window” contains a certain amount of residual soluble organic matter (SOM. This SOM have an important influence on characterization of shale reservoir. In this study, two shale samples were collected from the Upper Permian Dalong Formation in the northwestern boundary of Sichuan Basin. Their geochemistry, mineral composition, and pore structure (surface area and pore volume were investigated before and after removing the SOM by means of extraction via dichloromethane or trichloromethane. The results show that the TOC, S1, S2, and IH of the extracted samples decrease significantly, but the mineral composition has no evident change as compared with their raw samples. Thus, we can infer that the original pore structure is thought to be unaffected from the extraction. The SOM occupies pore volume and hinders pores connectivity. The extraction greatly increases the surface area and pore volume of the samples. The residual SOM in the shale samples occur mainly in the micropores and smaller mesopores, and their occupied pore size range seems being constrained by the maturity. For the lower mature shale samples, the SOM is mainly hosted in organic pores that are less than 5 nm in size. For the middle mature shale samples, the micropores and some mesopores ranging between 2 and 20 nm in size are the main storage space for the SOM.

  11. Microbial control of soil organic matter mineralization responses to labile carbon in subarctic climate change treatments.

    Science.gov (United States)

    Rousk, Kathrin; Michelsen, Anders; Rousk, Johannes

    2016-12-01

    Half the global soil carbon (C) is held in high-latitude systems. Climate change will expose these to warming and a shift towards plant communities with more labile C input. Labile C can also increase the rate of loss of native soil organic matter (SOM); a phenomenon termed 'priming'. We investigated how warming (+1.1 °C over ambient using open top chambers) and litter addition (90 g m -2  yr -1 ) treatments in the subarctic influenced the susceptibility of SOM mineralization to priming, and its microbial underpinnings. Labile C appeared to inhibit the mineralization of C from SOM by up to 60% within hours. In contrast, the mineralization of N from SOM was stimulated by up to 300%. These responses occurred rapidly and were unrelated to microbial successional dynamics, suggesting catabolic responses. Considered separately, the labile C inhibited C mineralization is compatible with previously reported findings termed 'preferential substrate utilization' or 'negative apparent priming', while the stimulated N mineralization responses echo recent reports of 'real priming' of SOM mineralization. However, C and N mineralization responses derived from the same SOM source must be interpreted together: This suggested that the microbial SOM-use decreased in magnitude and shifted to components richer in N. This finding highlights that only considering SOM in terms of C may be simplistic, and will not capture all changes in SOM decomposition. The selective mining for N increased in climate change treatments with higher fungal dominance. In conclusion, labile C appeared to trigger catabolic responses of the resident microbial community that shifted the SOM mining to N-rich components; an effect that increased with higher fungal dominance. Extrapolating from these findings, the predicted shrub expansion in the subarctic could result in an altered microbial use of SOM, selectively mining it for N-rich components, and leading to a reduced total SOM-use. © 2016 John Wiley

  12. Forholdet mellem public relations og marketing som ledelsesfunktioner

    Directory of Open Access Journals (Sweden)

    James E. Grunig

    1993-09-01

    Full Text Available I forsommeren 1993 tildelte Dansk Public Relations Forening årets PR- pris til mesterkommunikatøren Lars Larsen, Jysk Sengetøjslager/Larsen Rejser. I motiveringen hedder det, at Lars Larsen hædres for "en prisvær- dig Public Relations indsats, der kan motivere til en øget anvendelse af Public Relations i den danske forretningsverden". Blandt PR-foreningens medlemmer vakte pristildelingen en vis furore; et indlæg i foreningens blad PRspektiv invendte, at Lars Larsen driver "publicity" (dvs. et reklame- værktøj - "Præcis den slags PR, som vi i mange år har arbejdet på at distancere Public Relation-begrebet fra". Lars Larsen selv sagde, at han slet ikke skelner mellem Public Relations, PR og markedsføring. Et andet indlæg i bladet argumenterede for, at det ikke længere giver mening at adskille begreberne Public Relations og markedsføring, fordi grænsen mellem det offentlige og det private ude i virkeligheden er mere og mere flydende. James Grunigs artikel, der søger at afklare forholdet mellem PR og marketing teoretisk og praktisk, er derfor brændende aktuelt, ikke mindst for PR-fagets bestræbelser på at blive anerkendt som en respek- tabel profession. Den blev præsenteret som foredrag under Grunigs Dan- marksbesøg i marts 1993, er redigeret af Kim Schrøder og oversat fra engelsk af Kenja Henriksen.

  13. John Deweys pædagogik som filosofisk livskunst

    DEFF Research Database (Denmark)

    Dræby, Anders

    De senere år har der været forøget fokus på John Deweys slægtskab med antikkens filosofiske tradition. Oplægget stiller i den forbindelse skarpt på spørgsmålet om, hvorvidt og hvordan det giver mening at forstå Deweys pædagogiske filosofi i sammenhæng med Hellenismens og Romerrigets filosofiske...... livskunst. Er det med andre ord muligt at begribe Deweys pædagogik som en særlig form for filosofisk livskunst?...

  14. The origin of soil organic matter controls its composition and bioreactivity across a mesic boreal forest latitudinal gradient

    Science.gov (United States)

    Kohl, L.; Philben, M. J.; Edwards, K. A.; Podrebarac, F. A.; Jamie, W.; Ziegler, S. E.

    2017-12-01

    Warmer climates have been associated with reduced soil organic matter (SOM) bioreactivity, lower respiration rates at a given temperature, which is typically attributed to the presence of more decomposed SOM. Cross site studies, however, indicate that ecosystem regime shifts associated with long-term climate warming can affect SOM properties through changes in vegetation and plant litter inputs to soils. The relative importance of these two controls, diagenesis and inputs, on SOM properties as ecosystems experience climate warming remains poorly understood. To address this, we characterized the elemental, chemical (nuclear magnetic resonance spectroscopy and total hydrolysable amino acids), and isotopic composition of plant litter and SOM across a well-constrained mesic boreal forest latitudinal transect in Atlantic Canada. Results across forest sites within each of three climate regions indicated that (1) climate history and diagenesis affect distinct parameters of SOM chemistry, (2) increases in SOM bioreactivity with latitude were associated with elevated proportions of carbohydrates relative to plant waxes and lignin, and (3) despite the common forest type across regions, differences in SOM chemistry by climate region were associated with chemically distinct litter inputs and not different degrees of diagenesis. Climate effects on vascular plant litter chemistry explained only part of the regional differences in SOM chemistry, most notably the higher protein content of SOM from warmer regions. Greater proportions of lignin and aliphatic compounds and smaller proportions of carbohydrates in warmer sites' soils were explained by the higher proportion of vascular plant relative to moss litter in the warmer forests. These results indicate that a climate induced decrease in the proportion of moss inputs will not only impact SOM chemistry but also increase the resistance of SOM to decomposition, thus significantly altering SOM cycling in these boreal forest soils.

  15. SPECTRAL COLOR INDICES BASED GEOSPATIAL MODELING OF SOIL ORGANIC MATTER IN CHITWAN DISTRICT, NEPAL

    Directory of Open Access Journals (Sweden)

    U. K. Mandal

    2016-06-01

    Full Text Available Space Technology provides a resourceful-cost effective means to assess soil nutrients essential for soil management plan. Soil organic matter (SOM is one of valuable controlling productivity of crops by providing nutrient in farming systems. Geospatial modeling of soil organic matter is essential if there is unavailability of soil test laboratories and its strong spatial correlation. In the present analysis, soil organic matter is modeled from satellite image derived spectral color indices. Brightness Index (BI, Coloration Index (CI, Hue Index (HI, Redness Index (RI and Saturation Index (SI were calculated by converting DN value to radiance and radiance to reflectance from Thematic Mapper image. Geospatial model was developed by regressing SOM with color indices and producing multiple regression model using stepwise regression technique. The multiple regression equation between SOM and spectral indices was significant with R = 0. 56 at 95% confidence level. The resulting MLR equation was then used for the spatial prediction for the entire study area. Redness Index was found higher significance in estimating the SOM. It was used to predict SOM as auxiliary variables using cokringing spatial interpolation technique. It was tested in seven VDCs of Chitwan district of Nepal using Thematic Mapper remotely sensed data. SOM was found to be measured ranging from 0.15% to 4.75 %, with a mean of 2.24 %. Remotely sensed data derived spectral color indices have the potential as useful auxiliary variables for estimating SOM content to generate soil fertility management plans.

  16. Pool gateway seal

    International Nuclear Information System (INIS)

    Starr, J.A.; Steinert, L.A.

    1983-01-01

    A device for sealing a gateway between interconnectable pools in a nuclear facility comprising a frame supporting a liquid impermeable sheet positioned in a u-shaped gateway between the pools. An inflatable tube carried in a channel in the periphery of the frame and adjoining the gateway provides a seal therebetween when inflated. A restraining arrangement on the bottom edge of the frame is releasably engagable with an adjacent portion of the gateway to restrict the movement of the frame in the u-shaped gateway upon inflation of the tube, thereby enhancing the seal. The impermeable sheet is formed of an elastomer and thus is conformable to a liquid permeable supportive wall upon application of liquid pressure to the side of the sheet opposite the wall

  17. Backfitting swimming pool reactors

    International Nuclear Information System (INIS)

    Roebert, G.A.

    1978-01-01

    Calculations based on measurements in a critical assembly, and experiments to disclose fuel element surface temperatures in case of accidents like stopping of primary coolant flow during full power operation, have shown that the power of the swimming pool type research reactor FRG-2 (15 MW, operating since 1967) might be raised to 21 MW within the present rules of science and technology, without major alterations of the pool buildings and the cooling systems. A backfitting program is carried through to adjust the reactor control systems of FRG-2 and FRG-1 (5 MW, housed in the same reactor hall) to the present safety rules and recommendations, to ensure FRG-2 operation at 21 MW for the next decade. (author)

  18. Distribution of some organic components in two forest soils profiles with evidence of soil organic matter leaching.

    Science.gov (United States)

    Álvarez-Romero, Marta; Papa, Stefania; Lozano-García, Beatriz; Parras-Alcántara, Luis; Coppola, Elio

    2015-04-01

    Soil stores organic carbon more often than we can find in living vegetation and atmosphere together. This reservoir is not inert, but it is constantly in a dynamic phase of inputs and losses. Soil organic carbon mainly depends on land cover, environment conditions and soil properties. After soil deposition, the organic residues of different origin and nature, the Soil Organic Matter (SOM) can be seen involved in two different processes during the pedogenesis: mineralization and humification. The transport process along profile happens under certain conditions such as deposition of high organic residues amount on the top soil, high porosity of the soil caused by sand or skeleton particles, that determine a water strong infiltrating capacity, also, extreme temperatures can slow or stop the mineralization and/or humification process in one intermediate step of the degradation process releasing organic metabolites with high or medium solubility and high loads of water percolating in relation to intense rainfall. The transport process along soil profile can take many forms that can end in the formation of Bh horizons (h means accumulation of SOM in depth). The forest cover nature influence to the quantity and quality of the organic materials deposited with marked differences between coniferous and deciduous especially in relation to resistance to degradation. Two soils in the Campania region, located in Lago Laceno (Avellino - Italy) with different forest cover (Pinus sp. and Fagus sp.) and that meets the requirements of the place and pedological formation suitable for the formation and accumulation of SOM in depth (Bh horizon) were studied. The different soil C fractions were determinated and were assessed (Ciavatta C. et al. 1990; Dell'Abate M.T. et al. 2002) for each soil profile the Total Extractable Lipids (TEL). Furthermore, the lignin were considered as a major component of soil organic matter (SOM), influencing its pool-size and its turnover, due to the high

  19. Med sjefen på Facebook: En studie av ledere som er "venner" med sine ansatte

    OpenAIRE

    Jensen, Anita

    2014-01-01

    MR690 Masteroppgave i organisasjon og ledelse - utdanningsledelse Formålet med studien er å belyse hvordan aktiv bruk av sosiale medier, i dette tilfellet Facebook, påvirker relasjoner mellom mennesker. Hva skjer når en tar i bruk en websjanger som i utgangspunktet er umiddelbar og uformell, til jobbrelatert og mer formell kommunikasjon? Er det sjangeren eller relasjonen som endres? Søkelyset rettes mot ledere som er “venner” med sine medarbeidere, og problemstillingen er...

  20. Fuel assembly storage pool

    International Nuclear Information System (INIS)

    Hiranuma, Hiroshi.

    1976-01-01

    Object: To remove limitation of the number of storage of fuel assemblies to increase the number of storage thereof so as to relatively reduce the water depth required for shielding radioactive rays. Structure: Fuel assembly storage rack containers for receiving a plurality of spent fuel assembly racks are stacked in multi-layer fashion within a storage pool filled with water for shielding radioactive rays and removing heat. (Furukawa, Y.)

  1. CERN Electronics Pool presentations

    CERN Multimedia

    2011-01-01

    The CERN Electronics Pool has organised a series of presentations in collaboration with oscilloscope manufacturers. The last one will take place according to the schedule below.   Time will be available at the end of the presentation to discuss your personal needs. The Agilent presentation had to be postponed and will be organised later. -     Lecroy: Thursday, 24 November 2011, in 530-R-030, 14:00 to 16:30.

  2. Validering som kommunikationsfärdighet till par där kvinnan har vaginism

    OpenAIRE

    Bernling, Marit; Munck af Rosenschöld, Lisa

    2009-01-01

    Vaginism är ett sexuellt problem som förekommer hos kvinnor och som i tidigare utvärderade behandlingar betraktats som kvinnans problem. Forskning inom området vaginism är begränsad och kunskap om parrelationens roll för vidmakthållandet av problematiken och upplevd relationstillfredsställelse saknas. Studiens syfte var att utforma en parbehandling där kommunikationsinterventionen validering lärs ut som färdighet, utforska om det fanns ett intresse för deltagande, samt utvärdera om behandling...

  3. Studerendes caseundersøgelser som omdrejningspunkt for forskningsbaseret holdundervisning

    Directory of Open Access Journals (Sweden)

    Nina Bonderup Dohn

    2013-03-01

    Full Text Available Artiklen indledes med en diskussion af, hvori forskningsbaseret undervisning (FU består. Vi bestemmer FU som undervisning, hvor studerende involveres som aktive deltagere i processen med at producere ny viden ved brug af forskningsmetode. Vores overordnede forskningsspørgsmål lyder: Hvilke muligheder giver et didaktisk design baseret på, at de studerende inddrages som bidragydere til forskningsprocessen, for at realisere de forskellige begrundelser for forskningsbaseret undervisning? Hvilke problemstillinger viser der sig i forsøget herpå? Spørgsmålet undersøges med fokus på læringsteoretiske begrundelser og filosofiske begrundelser for FU. Vi rapporterer resultater fra et følgeforskningsprojekt i et undervisningsforløb, designet ud fra vores bestemmelse af FU. I diskussionen argumenterer vi for, at de læringsteoretiske begrundelser har rimelige muligheder for at realiseres med det didaktiske design, mens de filosofiske begrundelser kræver mere understøttelse. Resultaterne peger på en række problemstillinger og barrierer for realiseringen af FU (i en bestemmelse som vores og af begrundelserne for FU. Blandt disse er, at det didaktiske design indebærer en uvant arbejds- og studieform for de studerende, at der kan være en spænding mellem studieordningens faglige mål og FU (i en bestemmelse som vores, og at studerendes instrumentalistiske, erhvervsrettede mål kan være en barriere for realisering af de filosofiske begrundelser for FU. The article starts with a short discussion of different views on research-based teaching (RT. We characterize RT as teaching where students are involved as active participants in the process of producing new knowledge through the use of research methods. Our overall research question is: What possibilities does a pedagogical design based on involving students as contributors to the research process offer for realizing the different reasons for RT? What problems can arise? The research question

  4. Swimming Pools and Molluscum Contagiosum

    Science.gov (United States)

    ... Travelers’ Health: Smallpox & Other Orthopoxvirus-Associated Infections Poxvirus Swimming Pools Recommend on Facebook Tweet Share Compartir The ... often ask if molluscum virus can spread in swimming pools. There is also concern that it can ...

  5. New analytical technique for establishing the quality of Soil Organic Matter affected by a wildfire. A first approach using Fourier transform ion cyclotron resonance mass spectrometry

    Science.gov (United States)

    Jiménez-Morillo, Nicasio T.; González-Pérez, José A.; Waggoner, Derek C.; Almendros, Gonzalo; González-Vila, Francisco J.; Hatcher, Patrick G.

    2016-04-01

    lignin-like regions, indicating the input of fresh organic matter. The presence of molecular formulas which plot in the aromatic and condensed aromatics regions also indicates that this fraction may have contributions from a second, more recalcitrant, organic carbon pool. The appearance of aromatic and condensed aromatic compounds could suggest that, in this fraction the fire induced condensation processes. In the burnt fine fraction, two different SOM sources of alteration could be identified; i) from microbial origin with high relative intensity of lipid-like and protein-like compounds and ii) fire origin with large amounts of condensed aromatic compounds and a high contribution from the carbohydrate-like compounds region. We suggest that these results indicate both, condensation processes yielding black carbon like materials and additions from the coarse fraction during fire mediated distillation process. Acknowledgements: This study is part of the results of the GEOFIRE Project (CGL2012-38655-C04-01) funded by the Spanish Ministry for Economy and Competitiveness. N.T Jiménez-Morillo is funded by a FPI research grant and EEBB 2015 research grant (BES-2013-062573 and EEBB-I-15-09334 respectively). In addition, we thank the large number of individuals in the Hatcher research group who contributed indirectly to the work presented here. References: González-Pérez JA, González-Vila FJ, Almendros G, Knicker H. 2004. The effect of fire on soil organic matter - a review. Environment International 30, 855-870. DOI:10.1016/j.envint.2004.02.003. Jiménez-Morillo NT, González-Pérez JA, Jordán A, Zavala LM, de la Rosa JM, Jiménez-González MA, González-Vila FJ. 2014. Organic matter fractions controlling soil water repellency in sandy soils from the Doñana National Park (Southwestern Spain). Land Degradation & Development. DOI: 10.1002/ldr.2314. Kim S, Kramer RW, and Hatcher PG. 2003. An informative graphical method for analysis of ultrahigh-resolution broadband mass

  6. The influence of bioturbation on the vertical distribution of soil organic matter in volcanic ash soils: a case study in northern Ecuador

    NARCIS (Netherlands)

    Tonneijck, F.H.; Jongmans, A.G.

    2008-01-01

    Soil faunal bioturbation ('bioturbation') is often cited as a major process influencing the vertical distribution of soil organic matter (SOM). The influence of bioturbation on vertical SOM transport is complex because it is the result of interaction between different groups of soil faunal species

  7. Differences in chemical composition of soil organic matter in natural ecosystems from different climatic regions: a pyrolysis-GC/MS study

    NARCIS (Netherlands)

    Vancampenhout, K.; Wouters, K.; Vos, de B.; Buurman, P.; Swennen, R.; Deckers, J.

    2009-01-01

    Soil organic matter (SOM) is a key factor in ecosystem dynamics. A better understanding of the global relationship between environmental characteristics, ecosystems and SOM chemistry is vital in order to assess its specific influence on carbon cycles. This study compared the composition of extracted

  8. Compositional changes of soil organic matter with cropping time were more profound in subsoils and distinct between Phaeozem and Chernozem in Northeast China

    Science.gov (United States)

    Soil organic matter (SOM) contributes to soil processes and is found both in shallow and deep soil layers. Its activity can be affected by its chemical composition, yet knowledge is incomplete of how land use alters the structural composition of SOM throughout the profiles of different soil types. T...

  9. Long-term effects of fallow, tillage and manure application on soil organic matter and nitrogen fractions and on sorghum yield under Sudano-Sahelian conditions

    NARCIS (Netherlands)

    Mando, A.; Ouattara, B.; Somado, A.E.; Wopereis, M.C.S.; Stroosnijder, L.; Breman, H.

    2005-01-01

    Soil organic matter (SOM) controls the physical, chemical and biological properties of soil and is a key factor in soil productivity. Data on SOM quantity and quality are therefore important for agricultural sustainability. In 1990, an experiment was set up at Saria, Burkina Faso on a sandy loam

  10. Comparing NaOH-extractable organic matter of acid forest soils that differ in their pedogenic trends: a pyrolysis-GC/MS study

    NARCIS (Netherlands)

    Suarez Abelenda, M.; Buurman, P.; Camps Arbestain, M.; Kaal, J.; Martinez-Cortizas, A.; Gartzia-Bengoetxea, N.; Macias, F.

    2011-01-01

    Soil organic matter (SOM) in Alu-andic Andosols and Alu-humic Umbrisols is believed to accumulate because of the protection caused by binding to aluminium (Al). We investigated soils that differed in the abundance of organo-Al complexes to determine the effect of such binding on SOM chemistry. For

  11. Pool-type reactor

    International Nuclear Information System (INIS)

    Hopkins, S.R.

    1977-01-01

    This invention relates to a pool nuclear reactor fitted with a perfected system to raise the buckets into a vertical position at the bottom of a channel. This reactor has an inclined channel to guide a bucket containing a fuel assembly to introduce it into the reactor jacket or extract it therefrom and a damper at the bottom of the channel to stop the drop of the bucket. An upright vertically movable rod has a horizontally articulated arm with a hook. This can pivot to touch a radial lug on the bucket and pivot the bucket around its base in a vertical position, when the rod moves up [fr

  12. Litteraturarbete i ett svenska som andraspråksklassrum

    Directory of Open Access Journals (Sweden)

    Catarina Economou

    2015-06-01

    Full Text Available AbstractThis article considers the role of reading fiction in Swedish as a second language instruction. The study examines how a group of advanced second language learners in a Swedish upper secondary school read, interpret and discuss a contemporary Swedish novel, how they interact with the text and with each other in relation to the text. Furthermore, it analyses which forms of reading the students use. It is a qualitative, empirical study based on field studies, transcriptions of tape recorded interaction and of written texts. The results indicate that second language learners in this context have a positive attitude towards reading and discussing what they read using several forms of reading. They often compare the content of the text to their own lives. One conclusion is that literature teaching and literature can be integrated into one Swedish subject in order to create even more meaningful interactions between students from different backgrounds. Another is that literature can be a means of language development as well as personal development.Keywords: Second language learners, literature pedagogy and didactics, forms of reading, democracy. SammandragDenna artikel handlar om skönlitteraturens roll i skolämnet svenska som andraspråk. Studien undersöker hur en grupp avancerade andraspråksinlärare i en svensk gymnasieskola läser, tolkar och diskuterar en modern svensk roman och hur de interagerar med texten och med varandra i relation till texten. Dessutom analyseras vilka läsarter som eleverna använde sig av. Den är en kvalitativ, empirisk studie som baseras på fältstudier, transkriptioner av inspelade boksamtal och elevtexter. Resultaten visar att andraspråkseleverna hade en positiv attityd till boksamtal och de använde sig av flera läsarter. De jämförde ofta texten till sina egna liv och erfarenheter.  En slutsats är att litteraturundervisning och litteraturarbete skulle kunna integreras i ett gemensamt ämne så att

  13. Fjernsynet som shaman: Om store mediebegivenheders transformative virkninger

    Directory of Open Access Journals (Sweden)

    Daniel Dayan

    1988-08-01

    Full Text Available Den direkte transmission af levende begivenheder har altid været TV- mediets særlige styrke, hvad enten det drejer sig om fodboldkampe, Lørdagskanalen eller kongebrylluper. Medieforskerne har da også interesseret sig for fjernsynets formidling af sportsbegivenheder og der er blevet lavet analyser af Kanaludsendelserne. Men hverken i Danmark eller andre steder har forskerne fundet det interessant at undersøge de store, ceremonielle mediebegivenheder. Det er Dayan & Katz´ projekt at udfylde dette tomrum i medie- og kul- turforskningen: Hvad er det, der fascinerer millioner ved disse TV- ceremonier, der ofte ikke blot henvender sig til et enkelt lands seere, men transmitteres til og ses af store dele af verden? Hvordan fungere disse begivenheder - hvad enten det drejer sig om Præsident Kennedys begravelse, Sadats besøg i Jerusalem, Månelandingen eller Watergate- høringerne - ideologisk, og hvilke interesser tjener de dermed i den politiske offentlighed? I denne artikel, der er et bearbejdet uddrag af den bog, projektet skal munde ud i, beskæftiger Dayan & Katz sig især med det de kalder "transformative" mediebegivenheder, dvs. TV-ceremonier der markerer, at et samfund står ved en tærskel mellem den herskende orden og en ny mulig orden, og som selv er et aktivt og aktiverende bidrag til forvand- lingen af kulturelle opfattelser og værdier. Artiklens perpektiv er udpræget tværvidenskabeligt, idet der trækkes på såvel kulturantropologiske (Levi-Strauss, Geertz, Turner som filosofiske (Bakhtin, Baudrillard, sprogteoretiske (Austin og traditionelt samfunds- videnskabelige/mediesociologiske (Boorstin arbejder. I artiklens første halvdel foretages der en afgrænsning af transformative over for andre ceremonielle begivenheder. I anden halvdel gennemgås de fem faser, som udgør transformative begivenheders typiske struktur. Artiklen er bearbejdet af Jørgen Bang og Kim Schrøder. Den er oversat af Kim Schrøder.

  14. The impact of long-term elevated CO2 on C and N retention in stable SOM pools

    NARCIS (Netherlands)

    Graaff, de M.A.; Kessel, van C.; Six, J.

    2008-01-01

    Elevated atmospheric CO2 frequently increases plant production and concomitant soil C inputs, which may cause additional soil C sequestration. However, whether the increase in plant production and additional soil C sequestration under elevated CO2 can be sustained in the long-term is unclear. One

  15. Soil organic matter change - analysis on a regional scale of Austria

    Science.gov (United States)

    Gruendling, Ralf; Franko, Uwe; Sedy, Katrin; Freudenschuß, Alexandra; Spiegel, Adelheid; Formayer, Herbert

    2014-05-01

    Soil organic matter (SOM) is an important resource in agriculture. It influences soil fertility, erosion processes and prevents soil degradation. However, SOM is strongly affected by climate change, soil conditions and management alterations. The presented study analyzes SOM changes in Austria on a regional scale in the "Marchfeld" and the "Muehlviertel". For quantification these SOM changes the model CCB (Candy Carbon Balance) was used. Based on a 1 square kilometer raster, the impact of specific site conditions on SOM are determined to characterize the study areas. Used as a main indicator for these conditions is the biologic active time (BAT). BAT describes the biologic activity for carbon cycling in top soils depending on soil and climatic conditions. High values of BAT indicate fast SOM reproduction rates. Hence, BAT changes over last years signpost the risk of SOM loss and can be used as an on-farm decision tool. The change of risks of SOM loss due to climate change is assessed by model results. Therefore, three climate scenarios are used to compute reproduction rates of SOM. "High risk-regions" can be identified for policy consulting. Different climate scenarios can help to develop best case and worst case results. First results show that the region "Marchfeld" had a higher change in BAT during last 2 decades comparing to the "Muehlviertel". A higher risk of SOM loosing is evident. Nevertheless, future scenarios predict a higher change of BAT for the "Muehlviertel". Apparently, the sensitivity of "Marchfeld" sites regard to climate change has been higher in the past and most BAT changes took place until now. With this method an evaluation of farm management in regard to SOM reproduction and recommendation of crop rotations for the future are possible. In conclusion, the aim of the project is a tool box for farmers and policy makers to evaluate present and future agricultural management. An examination of additional regions in Austria is planned.

  16. ADHD SOM SOCIALT OG KULTURELT FÆNOMEN

    DEFF Research Database (Denmark)

    Berger, Nichlas Permin

    Der har i Danmark de seneste årtier været en eksplosiv vækst i antallet af mennesker, der stilles en ADHD-diagnose. Der eksisterer et væld af forskellige bud på forklaringer på dette fænomen. Lige fra epidemiologiske og medicinske tolkninger, der peger på, at mennesker generelt er blevet mere syge...... at forbinde psykiske lidelser, herunder i væsentlig grad ADHD, som en risikofaktor for kriminalitet, antisocial adfærd, misbrug og en række andre sociale problemer. Med interesse i dette komplekse fænomen belyses empirisk den sociale og kulturelle forudsætning for ADHD-diagnosen i Kriminalforsorgens...... institutioner i en kulturanalytisk og socialkonstruktivistisk optik. Afhandlingen undersøger, hvordan ADHD og kriminalitet diskursivt kobles sammen af voksne kriminelle med en ADHD-diagnose og frontmedarbejdere i Kriminalforsorgen....

  17. Claus Beck-Nielsen som spøgelse

    DEFF Research Database (Denmark)

    Larsen, Peter Stein

    2012-01-01

    Med Brian Grahams artikel “Sympathy for the Spectres: The Double Nature of Blake’s Spectral Figures in Jerusalem” forbliver vi inden for den litterære tradition, men bevæger os en smule længere frem i tiden. Graham retter blikket mod William Blakes forfatterskab og påpeger, at Blakes univers er...... feministisk synsvinkel – er spøgelserne dobbelte: de spiller en rolle i kristendommens historie, samtidig med at de spiller en kontrasterende sympatisk rolle i den universelle strid mellem Blakes ”male and female powers”, denne evige strid mellem disse to poler ses af Blake som grundlaget for al skabelse og...

  18. Løgnene er ikke så nemme at huske som sandheden

    DEFF Research Database (Denmark)

    Bertelsen, Bettina

    2005-01-01

    Formålet med denne artikel er at belyse og diskutere, hvordan og hvorvidt prostituion kan forstås som et socialt problem. Dette vil jeg gøre gennem en teoretisk diskussion og analyse af prostitution som et socialt problem belyst ud fra konkrete projekterfaringer. Erfaringerne stammer dels fra...

  19. Gruppen som container og potentielt læringsrum gennem refleksion

    DEFF Research Database (Denmark)

    Søbirk, Helle Henni

    2012-01-01

    Al psykomotorisk intervention foregår i en relation mellem den psykomotoriske terapeut og individ eller gruppe. Derfor anses relations- og refleksionskompetencer som fagpersonlige kernekompetencer i den psykomotoriske praksis og er et centralt formål med "anvendte grupper" som hhv. udviklings-, t...

  20. Indexing Permafrost Soil Organic Matter Degradation Using High-Resolution Mass Spectrometry.

    Science.gov (United States)

    Mann, Benjamin F; Chen, Hongmei; Herndon, Elizabeth M; Chu, Rosalie K; Tolic, Nikola; Portier, Evan F; Roy Chowdhury, Taniya; Robinson, Errol W; Callister, Stephen J; Wullschleger, Stan D; Graham, David E; Liang, Liyuan; Gu, Baohua

    2015-01-01

    Microbial degradation of soil organic matter (SOM) is a key process for terrestrial carbon cycling, although the molecular details of these transformations remain unclear. This study reports the application of ultrahigh resolution mass spectrometry to profile the molecular composition of SOM and its degradation during a simulated warming experiment. A soil sample, collected near Barrow, Alaska, USA, was subjected to a 40-day incubation under anoxic conditions and analyzed before and after the incubation to determine changes of SOM composition. A CHO index based on molecular C, H, and O data was utilized to codify SOM components according to their observed degradation potentials. Compounds with a CHO index score between -1 and 0 in a water-soluble fraction (WSF) demonstrated high degradation potential, with a highest shift of CHO index occurred in the N-containing group of compounds, while similar stoichiometries in a base-soluble fraction (BSF) did not. Additionally, compared with the classical H:C vs O:C van Krevelen diagram, CHO index allowed for direct visualization of the distribution of heteroatoms such as N in the identified SOM compounds. We demonstrate that CHO index is useful not only in characterizing arctic SOM at the molecular level but also enabling quantitative description of SOM degradation, thereby facilitating incorporation of the high resolution MS datasets to future mechanistic models of SOM degradation and prediction of greenhouse gas emissions.

  1. Lekfull kreativitet. Fysiska användargränssnitt som erbjuder social och fysisk interaktion

    DEFF Research Database (Denmark)

    Brooks, Eva Irene

    2017-01-01

    I den här artikeln presenteras en studie som ägde rum under två år i fem olika förskolor i Danmark och som inkluderade 55 barn. Specifikt undersökte vi hur fysiska användargränssnitt kan stötta social och fysisk interaktion. Studien applicerade en design-baserad metodologi som följde en iterativ,......, cyklisk process. Analysen visade att fysiska gränssnitt som främjar utforskande aktiviteter, verbala interaktioner och samarbete har en potential att erbjuda lekfulla lärande situationer som understödjer fria men också guidade aktiviteter....

  2. Increasing Soil Organic Matter Enhances Inherent Soil Productivity while Offsetting Fertilization Effect under a Rice Cropping System

    Directory of Open Access Journals (Sweden)

    Ya-Nan Zhao

    2016-09-01

    Full Text Available Understanding the role of soil organic matter (SOM in soil quality and subsequent crop yield and input requirements is useful for agricultural sustainability. SOM is widely considered to affect a wide range of soil properties, however, great uncertainty still remains in identifying the relationships between SOM and crop yield due to the difficulty in separating the effect of SOM from other yield-limiting factors. Based on 543 on-farm experiments, where paired treatments with and without NPK fertilizer were conducted during 2005–2009, we quantified the inherent soil productivity, fertilization effect, and their contribution to rice yield and further evaluated their relationships with SOM contents under a rice cropping system in the Sichuan Basin of China. The inherent soil productivity assessed by rice grain yield under no fertilization (Y-CK was 5.8 t/ha, on average, and contributed 70% to the 8.3 t/ha of rice yield under NPK fertilization (Y-NPK while the other 30% was from the fertilization effect (FE. No significant correlation between SOM content and Y-NPK was observed, however, SOM content positively related to Y-CK and its contribution to Y-NPK but negatively to FE and its contribution to Y-NPK, indicating an increased soil contribution but a decreased fertilizer contribution to rice yield with increasing SOM. There were significantly positive relationships between SOM and soil available N, P, and K, indicating the potential contribution of SOM to inherent soil productivity by supplying nutrients from mineralization. As a result, approaches for SOM accumulation are practical to improve the inherent soil productivity and thereafter maintain a high crop productivity with less dependence on chemical fertilizers, while fertilization recommendations need to be adjusted with the temporal and spatial SOM variation.

  3. Carbon storage in soil: how different land uses affect particulate organic matter composition. A molecular approach using nuclear magnetic resonance spectroscopy.

    Science.gov (United States)

    Panettieri, Marco; Courtier-Murias, Denis; Rumpel, Cornelia; Dignac, Marie-France; Doumert, Bertrand; Chabbi, Abad

    2017-04-01

    The future soil carbon stocks in a climate change scenario is being closely monitored. However, the huge edaphoclimatic variability impedes to disclose the mechanisms which underlie the cycle of accumulation/mineralization of soil organic matter (SOM). Soil environment could be described as a complex three phases matrix in which gases, liquids, and solids are not uniformly mixed, and in which microbes, fungi, vegetal residues, and roots are continuously interacting with the soil matrix and with each other. Molecular analyses on soil samples are crucial to estimate how stable those pools are and to predict which practices may accumulate larger C stocks. However, the study of land use impact through molecular characterization of a complex mixture like SOM is a challenge that requires a multidisciplinary approach. The present study applied a combination of soil physical fractionation (separation by density of the particulate organic matter (POM) within water stable aggregate fractions) followed by nuclear magnetic resonance (NMR) spectroscopy as a way to overcome spatial variability and to quantify the changes in the composition of SOM induced by land-use changes. The objective of the study was to assess, at a molecular level, the impact of different land managements, i.e. the introduction of temporary (ley) grassland into cropping cycles, on the chemical composition of SOM. Soil samples were collected at the long-term experimental observatory in Lusignan (http://www.soere-acbb.com/), in which control plots under permanent grassland, permanent cropland, and bare fallow are part of the experiment. To improve the signal-to-noise ratio (especially in the aromatic-C region), samples were analyzed using a ramped cross polarization-single pulse/magic angle spinning (CPSP/MAS) experiment. Peak integrals of different spectral regions (indicating different compound classes) were compared between treatments and two different molecular mixing models, calibrated against standard

  4. Detecting climate-change responses of plants and soil organic matter using isotopomers

    Science.gov (United States)

    Schleucher, Jürgen; Ehlers, Ina; Segura, Javier; Haei, Mahsa; Augusti, Angela; Köhler, Iris; Zuidema, Pieter; Nilsson, Mats; Öquist, Mats

    2015-04-01

    Responses of vegetation and soils to environmental changes will strongly influence future climate, and responses on century time scales are most important for feedbacks on the carbon cycle, climate models, prediction of crop productivity, and for adaptation to climate change. That plants respond to increasing CO2 on century time scales has been proven by changes in stomatal index, but very little is known beyond this. In soil, the complexity of soil organic matter (SOM) has hampered a sufficient understanding of the temperature sensitivity of SOM turnover. Here we present new stable isotope methodology that allows detecting shifts in metabolism on long time scales, and elucidating SOM turnover on the molecular level. Compound-specific isotope analysis measures isotope ratios of defined metabolites, but as average of the entire molecule. Here we demonstrate how much more detailed information can be obtained from analyses of intramolecular distributions of stable isotopes, so-called isotopomer abundances. As key tool, we use nuclear magnetic resonance (NMR) spectroscopy, which allows detecting isotope abundance with intramolecular resolution and without risk for isotope fractionation during analysis. Enzyme isotope fractionations create non-random isotopomer patterns in biochemical metabolites. At natural isotope abundance, these patterns continuously store metabolic information. We present a strategy how these patterns can be used as to extract signals on plant physiology, climate variables, and their interactions. Applied in retrospective analyses to herbarium samples and tree-ring series, we detect century-time-scale metabolic changes in response to increasing atmospheric CO2, with no evidence for acclimatory reactions by the plants. In trees, the increase in photosynthesis expected from increasing CO2 ("CO2 fertilization) was diminished by increasing temperatures, which resolves the discrepancy between expected increases in photosynthesis and commonly observed

  5. Soil organic matter distribution and microaggregate characteristics as affected by agricultural management and earthworm activity

    OpenAIRE

    Pulleman, M M; Six, J; van Breemen, N; Jongmans, A G

    2005-01-01

    Stable microaggregates can physically protect occluded soil organic matter (SOM) against decomposition. We studied the effects of agricultural management on the amount and characteristics of microaggregates and on SOM distribution in a marine loam soil in the Netherlands. Three long-term farming systems were compared: a permanent pasture, a conventional-arable system and an organic-arable system. Whole soil samples were separated into microaggregates (53-250 mu m), 20-53 mu m and 20 mu m) ve...

  6. Monitoring organic loading to swimming pools by fluorescence excitation–emission matrix with parallel factor analysis (PARAFAC)

    DEFF Research Database (Denmark)

    Seredynska-Sobecka, Bozena; Stedmon, Colin; Boe-Hansen, Rasmus

    2011-01-01

    Fluorescence Excitation–Emission Matrix spectroscopy combined with parallel factor analysis was employed to monitor water quality and organic contamination in swimming pools. The fluorescence signal of the swimming pool organic matter was low but increased slightly through the day. The analysis...... revealed that the organic matter fluorescence was characterised by five different components, one of which was unique to swimming pool organic matter and one which was specific to organic contamination. The latter component had emission peaks at 420nm and was found to be a sensitive indicator of organic...... loading in swimming pool water. The fluorescence at 420nm gradually increased during opening hours and represented material accumulating through the day....

  7. Biochar effect on the mineralization of soil organic matter

    Directory of Open Access Journals (Sweden)

    Sander Bruun

    2012-05-01

    Full Text Available The objective of this work was to verify whether the addition of biochar to the soil affects the degradation of litter and of soil organic matter (SOM. In order to investigate the effect of biochar on the mineralization of barley straw, soil was incubated with 14C-labelled barley straw with or without unlabelled biochar. To investigate the effect of straw on the mineralization of biochar, soil was incubated with 14C-labelled biochar with or without straw. In addition, to investigate the effect of biochar on old SOM, a soil labelled by applying labelled straw 40 years ago was incubated with different levels of biochar. All experiments had a control treatment, without any soil amendment. The effect of biochar on the straw mineralization was small and nonsignificant. Without biochar, 48±0.2% of the straw carbon was mineralized within the 451 days of the experiment. In comparison, 45±1.6% of C was mineralized after biochar addition of 1.5 g kg-1. In the SOM-labelled soil, the organic matter mineralized more slowly with the increasing doses of biochar. Biochar addition at 7.7 g kg-1 reduced SOM mineralization from 6.6 to 6.3%, during the experimental period. The addition of 15.5 g kg-1 of biochar reduced the mineralized SOM to 5.7%. There is no evidence of increased degradation of either litter or SOM due to biochar addition; consequently, there is no evidence of decreased stability of SOM.

  8. Deep SOMs for automated feature extraction and classification from big data streaming

    Science.gov (United States)

    Sakkari, Mohamed; Ejbali, Ridha; Zaied, Mourad

    2017-03-01

    In this paper, we proposed a deep self-organizing map model (Deep-SOMs) for automated features extracting and learning from big data streaming which we benefit from the framework Spark for real time streams and highly parallel data processing. The SOMs deep architecture is based on the notion of abstraction (patterns automatically extract from the raw data, from the less to more abstract). The proposed model consists of three hidden self-organizing layers, an input and an output layer. Each layer is made up of a multitude of SOMs, each map only focusing at local headmistress sub-region from the input image. Then, each layer trains the local information to generate more overall information in the higher layer. The proposed Deep-SOMs model is unique in terms of the layers architecture, the SOMs sampling method and learning. During the learning stage we use a set of unsupervised SOMs for feature extraction. We validate the effectiveness of our approach on large data sets such as Leukemia dataset and SRBCT. Results of comparison have shown that the Deep-SOMs model performs better than many existing algorithms for images classification.

  9. Multi-SOM: an Algorithm for High-Dimensional, Small Size Datasets

    Directory of Open Access Journals (Sweden)

    Shen Lu

    2013-04-01

    Full Text Available Since it takes time to do experiments in bioinformatics, biological datasets are sometimes small but with high dimensionality. From probability theory, in order to discover knowledge from a set of data, we have to have a sufficient number of samples. Otherwise, the error bounds can become too large to be useful. For the SOM (Self- Organizing Map algorithm, the initial map is based on the training data. In order to avoid the bias caused by the insufficient training data, in this paper we present an algorithm, called Multi-SOM. Multi-SOM builds a number of small self-organizing maps, instead of just one big map. Bayesian decision theory is used to make the final decision among similar neurons on different maps. In this way, we can better ensure that we can get a real random initial weight vector set, the map size is less of consideration and errors tend to average out. In our experiments as applied to microarray datasets which are highly intense data composed of genetic related information, the precision of Multi-SOMs is 10.58% greater than SOMs, and its recall is 11.07% greater than SOMs. Thus, the Multi-SOMs algorithm is practical.

  10. Distribution of peptidergic populations in the human dentate gyrus (somatostatin [SOM-28, SOM-12] and neuropeptide Y [NPY]) during postnatal development.

    Science.gov (United States)

    Cebada-Sánchez, S; Insausti, R; González-Fuentes, J; Arroyo-Jiménez, M M; Rivas-Infante, E; Lagartos, M J; Martínez-Ruiz, J; Lozano, G; Marcos, P

    2014-10-01

    The postnatal development of the human hippocampal formation establishes the time and place at which we start autobiographical memories. However, data concerning the maturation of the neurochemical phenotypes characteristic of interneurons in the human hippocampus are scarce. We have studied the perinatal and postnatal changes of the dentate gyrus (DG) interneuron populations at three rostrocaudal levels. Immunohistochemically identified neurons and fibers for somatostatin (SOM-12 and SOM-28) and neuropeptide Y (NPY) and the co-localization of SOM-28 and NPY were analyzed. In total, 13 cases were investigated from late pregnancy (1 case), perinatal period (6 cases), first year (1 case), early infancy (3 cases), and late infancy (2 cases). Overall, the pattern of distribution of these peptides in the DG was similar to that of the adult. The distribution of cells was charted, and the cell density (number of positive cells/mm(2)) was calculated. The highest density corresponded to the polymorphic cell layer and was higher at pre- and perinatal periods. At increasing ages, neuron density modifications revealed a decrease from 5 postnatal months onward. In contrast, by late infancy, two immunoreactive bands for SOM-28 and NPY in the molecular layer were much better defined. Double-immunohistochemistry showed that NPY-positive neurons co-localized with SOM-28, whereas some fibers contained only one or other of the neuropeptides. Thus, this peptidergic population, presumably inhibitory, probably has a role in DG maturation and its subsequent functional activity in memory processing.

  11. Occurrence and abundance of carbohydrates and amino compounds in sequentially extracted labile soil organic matter fractions.

    Science.gov (United States)

    This study aimed to investigate the content of carbohydrates and amino compounds in three labile fraction of soil organic matter (SOM). Soil samples were collected from two agricultural fields in southern Italy and the light fraction (LF), the 500–53-µm particulate organic matter (POM) and the mobil...

  12. Soil Organic Matter and Soil Productivity: Searching for the Missing Link

    Science.gov (United States)

    Felipe G. Sanchez

    1998-01-01

    Soil-organic matter (SOM) is a complex array of components including soil fauna and flora at different stages of decomposition (Berg et al., 1982). Its concentration in soils can vary from 0.5% in mineral soils to almost 100% in peat soils (Brady, 1974). Organic matter (OM) in the surface mineral soil is considered a major determinant of forest ecosystem productivity...

  13. Utholdenhetstrening i fotball: En analyse av smålagsspill brukt som utholdenhetstrening

    OpenAIRE

    Lorvik, Knut

    2013-01-01

    Utholdenhet er en fysisk egenskap som har betydning for fotballprestasjonen. Det viser flere studier. Helgerud (et al. 2001) fant signifikante forbedringer i forhold til flere fysiske mål som ble testet. Impellizzeri (et al. 2008) fant i sin studie at en forbedring i VO2max påvirket kortpasningsferdighetene positivt. I denne oppgaven har jeg fokusert på utholdenhetstrening i fotball og har to problemstillinger. Den første problemstillingen handler om hvilke studier som er gjort av utholde...

  14. Børn med diagnoser som pædagogisk-psykologisk udfordring

    DEFF Research Database (Denmark)

    Bøttcher, Louise

    2013-01-01

    hovedsageligt vanskelighederne ud fra en social vinkel. Den artikels dialektiske balancegang mellem de to positioner vil udfolde en forståelse af diagnoser som ADHD eller autismespektrumforstyrrelser, som tager udgangspunkt i at en eller flere biologiske afvigelser meget vel kan være den oprindelige årsag til...... hvordan uoverensstemmelsen mellem barnet og omgivelserne skaber problemer og udfordringer, kan diagnosen blive nyttig. Nemlig som dialektisk redskab til at analysere de psykologiske og pædagogiske udviklingsmæssige konsekvenser af at have en psykisk udviklingsforstyrrelse af typen ASD eller ADHD – frem...

  15. Fiskeren som forsvant? En studie av avfolking, overbefolking og endringsprosesser i norsk fiskerinæring

    OpenAIRE

    Johnsen, Jahn Petter

    2003-01-01

    Hva er en fisker? Dette er det sentrale spørsmålet i denne avhandlinga. Spørsmålet er utgangspunkt for å utforske endringsprosesser i fiskerinæringa, både i fortida og i samtida. På bakgrunn av dette drøfter avhandlinga hvilke oppfatninger, forståelser og beskrivelser som til enhver tid benyttes til å definere hva fiskere er i ulike sammenhenger. Undersøkelsen starter i det som kan kalles rekrutteringsdiskursen i fiske, som nettopp handler om hva fiskere er og hvordan de skapes...

  16. Specialestuderendes læringsudfordringer i vejledningen - nudging som handlemulighed

    Directory of Open Access Journals (Sweden)

    Hanne Nexø Jensen

    2015-03-01

    Full Text Available Specialeskrivere møder læringsudfordringer i skriveprocessen. Hvilke læringsudfordringer, det er, og hvordan studerende og vejledere hånd-terer dem, er artiklens fokus. Empirien er videooptagede vejlednings-møder, hvor der er minimum to optagelser for hver vejleder og stude-rendes forløb. Det teoretiske afsæt er generiske læringsudfordringer i vejledningsprocesser, hvor læring opstår, når de studerende passerer en læringsudfordring. Vejledere kan bruge forståelsen af læringsudfor-dringer til at ”nudge”- plante en idé – som en måde at få studerende til at passere læringsudfordringerne. MA students writing up their final theses encounter a variety of conceptual thresholds during the process. The focus of this article is the identification of different kinds of conceptual threshold, and how the students overcome these obstacles. Video recordings of student supervision meetings provide the data for the analysis. For each supervisor – supervisee at least two recordings are considered. We go on to discuss how supervisors can make use of a conceptual thresholds approach, and nudge students in ways that will help them move on more easily.

  17. Overskridende læring - ADHD problematikken som eksempel

    DEFF Research Database (Denmark)

    Kristensen, Karen-Lis; Mørck, Line Lerche

    2011-01-01

    ADHD er en problematik, der i tiltagende grad fylder i medierne, i forældres bevidsthed, i klasseværelserne, i PPR-praksis og i den specialpædagogiske indsats. ADHD-problematikken er omstridt, og der er således mange forskellige perspektiver på, hvordan vi skal forstå ADHD. Er det udtryk for en...... patologisering af uro? Eller er der tale om genetisk betingede kognitive vanskeligheder med opmærksomhed og impulskontrol? Skyldes ADHD en forkert produktion og koncentration af sporstoffer i hjernen? Eller skyldes det, at kreativitet ikke i samme grad som tidligere kan rummes i skolernes klasseværelser? Er der...... handlesammenhæng, hvor de deltager” (Højholt, 1996: 62), søger vores tilgang på engang bedre både at forstå og fremme børns udvikling. Efter introduktion af teori om overskridende læring eksemplificerer vi tilgangen med to empiriske cases om 5. klasse-drengen, Anton, der ikke ønsker at tage sin medicin mod ADHD og...

  18. Specialestuderendes læringsudfordringer i vejledningen - nudging som handlemulighed

    Directory of Open Access Journals (Sweden)

    Hanne Nexø Jensen

    2015-03-01

    Full Text Available Specialeskrivere møder læringsudfordringer i skriveprocessen. Hvilke læringsudfordringer, det er, og hvordan studerende og vejledere hånd-terer dem, er artiklens fokus. Empirien er videooptagede vejlednings-møder, hvor der er minimum to optagelser for hver vejleder og stude-rendes forløb. Det teoretiske afsæt er generiske læringsudfordringer i vejledningsprocesser, hvor læring opstår, når de studerende passerer en læringsudfordring. Vejledere kan bruge forståelsen af læringsudfor-dringer til at ”nudge”- plante en idé – som en måde at få studerende til at passere læringsudfordringerne.  MA students writing up their final theses encounter a variety of conceptual thresholds during the process. The focus of this article is the identification of different kinds of conceptual threshold, and how the students overcome these obstacles. Video recordings of student supervision meetings provide the data for the analysis. For each supervisor – supervisee at least two recordings are considered. We go on to discuss how supervisors can make use of a conceptual thresholds approach, and nudge students in ways that will help them move on more easily.

  19. Model of large pool fires

    Energy Technology Data Exchange (ETDEWEB)

    Fay, J.A. [Department of Mechanical Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139 (United States)]. E-mail: jfay@mit.edu

    2006-08-21

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables.

  20. Model of large pool fires

    International Nuclear Information System (INIS)

    Fay, J.A.

    2006-01-01

    A two zone entrainment model of pool fires is proposed to depict the fluid flow and flame properties of the fire. Consisting of combustion and plume zones, it provides a consistent scheme for developing non-dimensional scaling parameters for correlating and extrapolating pool fire visible flame length, flame tilt, surface emissive power, and fuel evaporation rate. The model is extended to include grey gas thermal radiation from soot particles in the flame zone, accounting for emission and absorption in both optically thin and thick regions. A model of convective heat transfer from the combustion zone to the liquid fuel pool, and from a water substrate to cryogenic fuel pools spreading on water, provides evaporation rates for both adiabatic and non-adiabatic fires. The model is tested against field measurements of large scale pool fires, principally of LNG, and is generally in agreement with experimental values of all variables

  1. Design of hydrotherapy exercise pools.

    Science.gov (United States)

    Edlich, R F; Abidin, M R; Becker, D G; Pavlovich, L J; Dang, M T

    1988-01-01

    Several hydrotherapy pools have been designed specifically for a variety of aquatic exercise. Aqua-Ark positions the exerciser in the center of the pool for deep-water exercise. Aqua-Trex is a shallow underwater treadmill system for water walking or jogging. Swim-Ex generates an adjustable laminar flow that permits swimming without turning. Musculoskeletal conditioning can be accomplished in the above-ground Arjo shallow-water exercise pool. A hydrotherapy pool also can be custom designed for musculoskeletal conditioning in its shallow part and cardiovascular conditioning in a deeper portion of the pool. Regardless of the type of exercise, there is general agreement that the specific exercise conducted in water requires significantly more energy expenditure than when the same exercise is performed on land.

  2. Emma Bentz: I stadens skugga. Den medeltida landsbygden som arkeologiskt forskningsfält

    DEFF Research Database (Denmark)

    Kristiansen, Mette Svart

    2009-01-01

    Anmeldelse af doktordisputats, Lunds Universitet. Afhandlingen omhandler etableringen af den middelalderlige landbebyggelse som arkæologisk forskningsfelt fra 1930érne til i dag samt etableringen og vedligeholdelsen af et forskningsfelt indenfor den humanistiske videnskab....

  3. Increased precipitation accelerates soil organic matter turnover associated with microbial community composition in topsoil of alpine grassland on the eastern Tibetan Plateau.

    Science.gov (United States)

    Han, Conghai; Wang, Zongli; Si, Guicai; Lei, Tianzhu; Yuan, Yanli; Zhang, Gengxin

    2017-10-01

    Large quantities of carbon are stored in alpine grassland of the Tibetan Plateau, which is extremely sensitive to climate change. However, it remains unclear whether soil organic matter (SOM) in different layers responds to climate change analogously, and whether microbial communities play vital roles in SOM turnover of topsoil. In this study we measured and collected SOM turnover by the 14 C method in alpine grassland to test climatic effects on SOM turnover in soil profiles. Edaphic properties and microbial communities in the northwestern Qinghai Lake were investigated to explore microbial influence on SOM turnover. SOM turnover in surface soil (0-10 cm) was more sensitive to precipitation than that in subsurface layers (10-40 cm). Precipitation also imposed stronger effects on the composition of microbial communities in the surface layer than that in deeper soil. At the 5-10 cm depth, the SOM turnover rate was positively associated with the bacteria/fungi biomass ratio and the relative abundance of Acidobacteria, both of which are related to precipitation. Partial correlation analysis suggested that increased precipitation could accelerate the SOM turnover rate in topsoil by structuring soil microbial communities. Conversely, carbon stored in deep soil would be barely affected by climate change. Our results provide valuable insights into the dynamics and storage of SOM in alpine grasslands under future climate scenarios.

  4. Initial Soil Organic Matter Content Influences the Storage and Turnover of Litter-, Root- and Soil Carbon in Grasslands

    Science.gov (United States)

    Liu, L.; Xu, S.; Li, P.; Sayer, E. J.

    2017-12-01

    Grassland degradation is a worldwide problem that often leads to substantial loss of soil organic matter (SOM). Understanding how SOM content influences the stabilization of plant carbon (C) to form soil C is important to evaluate the potential of degraded grasslands to sequester additional C. We conducted a greenhouse experiment using C3 soils with six levels of SOM content and planted the C4 grass Cleistogenes squarrosa and/or added its litter to investigate how SOM content regulates the storage of new soil C derived from litter and roots, the decomposition of extant soil C, and the formation of soil aggregates. We found that microbial biomass carbon (MBC) increased with SOM content, and increased the mineralization of litter C. Both litter addition and planted treatments increased the amount of new C inputs to soil. However, litter addition had no significant impacts on the mineralization of extant soil C, but the presence of living roots significantly accelerated it. Thus, by the end of the experiment, soil C content was significantly higher in the litter addition treatments, but was not affected by planted treatments. The soil macroaggregate fraction increased with SOM content and was positively related to MBC. Overall, our study suggests that as SOM content increases, plant growth and soil microbes become more active, which allows microbes to process more plant-derived C and increases new soil C formation. The interactions between SOM content and plant C inputs should be considered when evaluating soil C turnover in degraded grasslands.

  5. The effect of composition on stability ({sup 14}C activity) of soil organic matter fractions from the albic and black soils

    Energy Technology Data Exchange (ETDEWEB)

    Jin, Jie [State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875 (China); Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 (United States); Sun, Ke, E-mail: sunke@bnu.edu.cn [State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875 (China); Wang, Ziying; Han, Lanfang [State Key Laboratory of Water Environment Simulation, School of Environment, Beijing Normal University, Beijing 100875 (China); Wu, Fengchang [State Key Laboratory of Environmental Criteria and Risk Assessment, Chinese Research Academy of Environmental Sciences, Beijing 100012 (China); Xing, Baoshan [Stockbridge School of Agriculture, University of Massachusetts, Amherst, MA 01003 (United States)

    2016-01-15

    The importance of the composition of soil organic matter (SOM) for carbon (C) cycling is still under debate. Here a single soil source was used to examine the specific influence of its composition on stability ({sup 14}C activity) of SOM fractions while constraining other influential C turnover factors such as mineral, climate and plant input. The following SOM fractions were isolated from two soil samples: four humic acids, two humins, non-hydrolyzable carbon, and the demineralized fraction. We examined the isotope ratios of SOM fractions in relation to composition (such as aliphatic and aromatic C content) using solid state {sup 13}C nuclear magnetic resonance (NMR) and thermal analysis. The Δ{sup 14}C values of the fractions isolated from both an albic soil (SOMs-A) and a black soil (SOMs-B) correlated negatively with their peak temperature of decomposition and the temperature where half of the total heat of reaction was evolved, implying a potential link between thermal and biogeochemical stability of SOM fractions. Aryl C contents of SOMs-A determined using {sup 13}C NMR varied inversely with δ{sup 15}N values and directly with δ{sup 13}C values, suggesting that part of aryl C of SOMs-A might be fire-derived. The Δ{sup 14}C values of SOMs-A correlated positively with aliphatic C content and negatively with aromatic C content. We therefore concluded that fire-derived aromatic C in SOMs-A appeared to be more stable than microbially-derived aliphatic C. The greater decomposition of SOMs-B fractions weakened the relationship of their Δ{sup 14}C values with alkyl and aryl C contents. Hence, the role of the composition of SOM fractions in regulating stability might be dependent on the source of specific C forms and their stage of decomposition. - Highlights: • The effect of composition on stability of SOM fractions (SOMs) was examined. • There was a potential link between thermal and biological stability of SOMs. • Fire-derived aromatic C was likely more

  6. The effect of composition on stability ("1"4C activity) of soil organic matter fractions from the albic and black soils

    International Nuclear Information System (INIS)

    Jin, Jie; Sun, Ke; Wang, Ziying; Han, Lanfang; Wu, Fengchang; Xing, Baoshan

    2016-01-01

    The importance of the composition of soil organic matter (SOM) for carbon (C) cycling is still under debate. Here a single soil source was used to examine the specific influence of its composition on stability ("1"4C activity) of SOM fractions while constraining other influential C turnover factors such as mineral, climate and plant input. The following SOM fractions were isolated from two soil samples: four humic acids, two humins, non-hydrolyzable carbon, and the demineralized fraction. We examined the isotope ratios of SOM fractions in relation to composition (such as aliphatic and aromatic C content) using solid state "1"3C nuclear magnetic resonance (NMR) and thermal analysis. The Δ"1"4C values of the fractions isolated from both an albic soil (SOMs-A) and a black soil (SOMs-B) correlated negatively with their peak temperature of decomposition and the temperature where half of the total heat of reaction was evolved, implying a potential link between thermal and biogeochemical stability of SOM fractions. Aryl C contents of SOMs-A determined using "1"3C NMR varied inversely with δ"1"5N values and directly with δ"1"3C values, suggesting that part of aryl C of SOMs-A might be fire-derived. The Δ"1"4C values of SOMs-A correlated positively with aliphatic C content and negatively with aromatic C content. We therefore concluded that fire-derived aromatic C in SOMs-A appeared to be more stable than microbially-derived aliphatic C. The greater decomposition of SOMs-B fractions weakened the relationship of their Δ"1"4C values with alkyl and aryl C contents. Hence, the role of the composition of SOM fractions in regulating stability might be dependent on the source of specific C forms and their stage of decomposition. - Highlights: • The effect of composition on stability of SOM fractions (SOMs) was examined. • There was a potential link between thermal and biological stability of SOMs. • Fire-derived aromatic C was likely more stable than microbial

  7. Novel estimation of the humification degree of soil organic matter by laser-induced breakdown spectroscopy

    Science.gov (United States)

    Ferreira, Edilene Cristina; Ferreira, Ednaldo José; Villas-Boas, Paulino Ribeiro; Senesi, Giorgio Saverio; Carvalho, Camila Miranda; Romano, Renan Arnon; Martin-Neto, Ladislau; Milori, Débora Marcondes Bastos Pereira

    2014-09-01

    Soil organic matter (SOM) constitutes an important reservoir of terrestrial carbon and can be considered an alternative for atmospheric carbon storage, contributing to global warming mitigation. Soil management can favor atmospheric carbon incorporation into SOM or its release from SOM to atmosphere. Thus, the evaluation of the humification degree (HD), which is an indication of the recalcitrance of SOM, can provide an estimation of the capacity of carbon sequestration by soils under various managements. The HD of SOM can be estimated by using various analytical techniques including fluorescence spectroscopy. In the present work, the potential of laser-induced breakdown spectroscopy (LIBS) to estimate the HD of SOM was evaluated for the first time. Intensities of emission lines of Al, Mg and Ca from LIBS spectra showing correlation with fluorescence emissions determined by laser-induced fluorescence spectroscopy (LIFS) reference technique were used to obtain a multivaried calibration model based on the k-nearest neighbor (k-NN) method. The values predicted by the proposed model (A-LIBS) showed strong correlation with LIFS results with a Pearson's coefficient of 0.87. The HD of SOM obtained after normalizing A-LIBS by total carbon in the sample showed a strong correlation to that determined by LIFS (0.94), thus suggesting the great potential of LIBS for this novel application.

  8. 14C dating and stable carbon isotopes of soil organic matter in the Southeastern region of Sao Paulo State

    International Nuclear Information System (INIS)

    Mofatto, Milene; Pessenda, Luiz Carlos Ruiz; Bendassoli, Jose Albertino; Leite, Acacio Zuniga; Oliveira, Paulo de Oliveira; Garcia, Ricardo Jose Francischetti

    2005-01-01

    The objective of this research is to characterize the isotopic composition ( 13 C, 14 C) of soil organic matter (SOM) in the Parque Estadual da Serra do Mar-Nucleo Curucutu, Sao Paulo state, Southeastern Brazil. The isotopic composition (δ 13 C) of SOM will be used as an indicator of vegetation types from the local ecosystems and 14 C dating (humin fraction) used to determine the chronology. The results from SOM indicated vegetation changes in the last 10,000 years, where, a less dense vegetation occurred in the past, with C 3 plant predominant and/or a mixture of C 3 and C 4 . (author)

  9. Preliminary results on the influence of mineralogy on the turnover rates of SOM from different Hungarian soils

    Science.gov (United States)

    Zacháry, Dóra; Szalai, Zoltán; Jakab, Gergely; Németh, Tibor; Sipos, Péter; Filep, Tibor

    2016-04-01

    Fine textured soils generally considered containing more microbial biomass, and having a lower rate of biomass turnover and organic matter decomposition than coarse textured soils. In spite of this, several recent studies have shown contradicting trends. For example, the relative importance of different clay minerals for stabilizing SOM remains an open question. The aim of this study is to evaluate soil mineralological effect on the turnover of SOM by identifying and quantifying soil phyllosilicates. Our samples are derived from C3 forests and C3 croplands from different sites of Hungary. C4 maize residues are added to the soils in order to get natural 13C enrichment as tracer for the young carbon. Bulk samples of the soils from 0 to 20 cm depth were collected. The samples were dried at room temperature and preincubated in the dark for 4 months at 20 °C. The basic soil properties (pH, cation exchange capacity) were analysed after 2 mm sieving and homogenization. The amount of total C and N in the soils and maize residues were analysed using NDIR-chemiluminescent analyzer (Tekmar Dohrman Apollo 9000N). Particle size distribution was determined by laser diffraction (Fritsch Analysette MicroTec 22 plus) and particle imaging method (Malvern Morphologi G3-ID). The mineralological composition of the samples was determined by X-ray diffraction (Philips PW 1730 X-ray diffractometer). Moist soil equivalent to 400 g dry soil mixed with 2 g maize leaves is kept in air tight glass chambers for 183 days at 20°C. The leaves had previously been dried at 60 °C, were cut into pieces and sieved through a 2 mm mesh. The evolved CO2 is trapped by 10 mL 2 M NaOH, which is exchanged on day 1, 3, 5, 7, 10, 14, 21, 28 and subsequently every 31 days. The fractional abundance of 13C of the soils, the plant material and the evolved CO2 is measured with isotope ratio mass spectrometer (Thermo Scientific Delta V IRMS). Our work show the preliminary results on the link between phyllosilicate

  10. ENERGY STAR Certified Pool Pumps

    Data.gov (United States)

    U.S. Environmental Protection Agency — Certified models meet all ENERGY STAR requirements as listed in the Version 1.1 ENERGY STAR Program Requirements for Pool Pumps that are effective as of February 15,...

  11. Pooling and correlated neural activity

    Directory of Open Access Journals (Sweden)

    Robert Rosenbaum

    2010-04-01

    Full Text Available Correlations between spike trains can strongly modulate neuronal activity and affect the ability of neurons to encode information. Neurons integrate inputs from thousands of afferents. Similarly, a number of experimental techniques are designed to record pooled cell activity. We review and generalize a number of previous results that show how correlations between cells in a population can be amplified and distorted in signals that reflect their collective activity. The structure of the underlying neuronal response can significantly impact correlations between such pooled signals. Therefore care needs to be taken when interpreting pooled recordings, or modeling networks of cells that receive inputs from large presynaptic populations. We also show that the frequently observed runaway synchrony in feedforward chains is primarily due to the pooling of correlated inputs.

  12. Grundfoss: Chlorination of Swimming Pools

    DEFF Research Database (Denmark)

    Hjorth, Poul G.; Hogan, John; Andreassen, Viggo

    1998-01-01

    Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools.......Grundfos asked for a model, describing the problem of mixing chemicals, being dosed into water systems, to be developed. The application of the model should be dedicated to dosing aqueous solution of chlorine into swimming pools....

  13. Sustainability of common pool resources

    OpenAIRE

    Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

    2017-01-01

    Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepales...

  14. Using soil organic matter fractions as indicators of soil physical quality

    DEFF Research Database (Denmark)

    Pulido Moncada, Mansonia A.; Lozano, Z; Delgado, M

    2018-01-01

    The objective of this study was to evaluate the use of chemical and physical fractions of soil organic matter (SOM), rather than SOM per se, as indicators of soil physical quality (SPQ) based on their effect on aggregate stability (AS). Chemically extracted humic and fulvic acids (HA and FA) were...... used as chemical fractions, and heavy and light fractions (HF and LF) obtained by density separation as physical fractions. The analyses were conducted on medium-textured soils from tropical and temperate regions under cropland and pasture. Results show that soil organic carbon (SOC), SOM fractions...... and AS appear to be affected by land use regardless of the origin of the soils. A general separation of structurally stable and unstable soils between samples of large and small SOC content, respectively, was observed. SOM fractions did not show a better relationship with AS than SOC per se. In both...

  15. Frozen gene pools - A future for species otherwise destined for extinction

    Science.gov (United States)

    Gee, G.F.

    1986-01-01

    Conclusion: Semen banks and ova and embryo banks can be practical methods to maintain gene pools. Gene pool preservation is desperately needed today due to the rapid decline in number of species and their habitat, a matter that is of concern to.biologists, economists, and politicians worldwide. Techniques are available for the cryopreservation of semen from many animals (and embryos from a few mammals) and adaptations of these techniques to other animals should be possible. A frozen gene pool in conjunction with existing programs makes it possible to preserve gene pools at less cost or in.some cases where no other alternative to extinction existed.

  16. 12 years of irrigation in a drought stressed pine forest speeds up carbon cycling and alters the soil biome but has negligible effects on soil organic matter storage

    Science.gov (United States)

    Hagedorn, Frank; Hartmann, Martin; Brunner, Ivano; Rigling, Andreas; Herzog, Claude; Schaub, Marcus; Frey, Beat

    2017-04-01

    Inneralpine valleys are experiencing repeated summer droughts, which have caused a die-back of pine forests since the 1990s. Drought limits the metabolic activity and hence C cycling in the plant and soil system. The net effects of drought on soil organic matter (SOM) storage is, however, ambiguous as drought affects both C inputs and outputs. Moreover, in the long-term, water limitation is also altering above- and belowground diversity due to species-dependent resistance and adaptation to drought. In our study, we explored how ten years of irrigation of a water-limited pine forest in the central European Alps altered above- and belowground diversity and C cycling in the plant and soil systems. The decadal long irrigation during summer time strongly increased ecosystem productivity with litter fall and fine root biomass being increased by +50 and +40%, respectively. At the same time, soil CO2 efflux was stimulated by 60%, indicating that the removal of water limitation enhanced both the inputs and outputs of C into soils. The accelerated C cycling was also mirrored by compositional shifts in the soil microbiome. 454-pyrosequencing of ribosomal marker genes indicated that irrigation promoted bacteria and fungi with more copiotrophic life style strategies, that are typical for nutrient-rich conditions associated with a higher decomposition. Determination of SOM pools revealed a C loss in the organic layer under irrigation (-900 gC m-2) but a C gain in the mineral soil (+970 gC m-2), resulting in a negligible net effect. The likely mechanisms for the altered vertical SOM distribution might be (1) an accelerated mineralization of litter in conjunction with higher C inputs from the rhizosphere and/or (2) an increased incorporation of litter in the mineral soil as suggested by a litter bag experiment showing a stimulated activity of the macrofauna with a 5-fold increase of the earthworm density. In summary, our long-term irrigation experiment revealed that the removal of

  17. Microbial control of soil organic matter mineralization responses to labile carbon in subarctic climate change treatments

    DEFF Research Database (Denmark)

    Rousk, Kathrin; Michelsen, Anders; Rousk, Johannes

    2016-01-01

    Half the global soil carbon (C) is held in high-latitude systems. Climate change will expose these to warming and a shift towards plant communities with more labile C input. Labile C can also increase the rate of loss of native soil organic matter (SOM); a phenomenon termed ‘priming’. We investig......Half the global soil carbon (C) is held in high-latitude systems. Climate change will expose these to warming and a shift towards plant communities with more labile C input. Labile C can also increase the rate of loss of native soil organic matter (SOM); a phenomenon termed ‘priming’. We...

  18. Seismic analysis of large pools

    Energy Technology Data Exchange (ETDEWEB)

    Dong, R.G.; Tokarz, F.J.

    1976-11-17

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated.

  19. Seismic analysis of large pools

    International Nuclear Information System (INIS)

    Dong, R.G.; Tokarz, F.J.

    1976-01-01

    Large pools for storing spent, nuclear fuel elements are being proposed to augment present storage capacity. To preserve the ability to isolate portions of these pools, a modularization requirement appears desirable. The purpose of this project was to investigate the effects of modularization on earthquake resistance and to assess the adequacy of current design methods for seismic loads. After determining probable representative pool geometries, three rectangular pool configurations, all 240 x 16 ft and 40 ft deep, were examined. One was unmodularized; two were modularized into 80 x 40 ft cells in one case and 80 x 80 ft cells in the other. Both embedded and above-ground installations for a hard site and embedded installations for an intermediate hard site were studied. It was found that modularization was unfavorable in terms of reducing the total structural load attributable to dynamic effects, principally because one or more cells could be left unfilled. The walls of unfilled cells would be subjected to significantly higher loads than the walls of a filled, unmodularized pool. Generally, embedded installations were preferable to above-ground installations, and the hard site was superior to the intermediate hard site. It was determined that Housner's theory was adequate for calculating hydrodynamic effects on spent fuel storage pools. Current design methods for seismic loads were found to be satisfactory when results from these methods were compared with those from LUSH analyses. As a design method for dynamic soil pressure, we found the Mononobe-Okabe theory, coupled with correction factors as suggested by Seed, to be acceptable. The factors we recommend for spent fuel storage pools are tabulated

  20. Enhancing the soil organic matter pool through biomass incorporation

    Science.gov (United States)

    Felipe G. Sanchez; Emily A. Carter; John F. Klepac

    2003-01-01

    A study was installed in the Upper Coastal Plain of South Carolina, USA that sought to examine the impact of incorporating downed slash materials into subsoil layers on soil chemical and physical properties as compared with the effect of slash materials left on the soil surface. Baseline levels of slash were estimated by establishing transects within harvested stands...

  1. Quantifying Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    Quantifying Matter explains how scientists learned to measure matter and quantify some of its most fascinating and useful properties. It presents many of the most important intellectual achievements and technical developments that led to the scientific interpretation of substance. Complete with full-color photographs, this exciting new volume describes the basic characteristics and properties of matter. Chapters include:. -Exploring the Nature of Matter. -The Origin of Matter. -The Search for Substance. -Quantifying Matter During the Scientific Revolution. -Understanding Matter's Electromagnet

  2. Hvordan ser den ost ud, som De ikke ved, De vil elske om to år?

    DEFF Research Database (Denmark)

    Grunert, Klaus G.

    2006-01-01

    Kender de Deres "latente behov"? Det gør De selvfølgelig ikke. Det er jo definitionen af begrebet: Et latent behov er et behov, som man ikke ved, at man har, men som kommer til overfladen, når man møder det rigtige produkt, som opfylder netop dette behov. Latente behov vedrører derfor den ost, vi...

  3. Safety evaluation and bacterial community of kung-som using PCR-DGGE technique

    Directory of Open Access Journals (Sweden)

    Sutanate Saelao

    2016-08-01

    Full Text Available This study evaluates the safety of kung-som which was distributed in local markets and using PCR-DGGE technique to identify microflora in kung-som. Lactic acid bacteria (LAB were found at counts of more than 7 log CFU g-1 in all samples and the total viable counts were about 5-8 log CFU g-1 . Bacillus cereus and yeasts were detected at around 2 log CFU g-1 and 5-6log CFU g-1, respectively. For DGGE analysis, LAB and coagulase negative staphylococci (CNS bacteria dominated over other microorganisms. The sequencing of the DNA bands from DGGE gels corresponding to kung-som samples showed the presence of LAB as the major microflora in the products, namely: Lactobacillus farciminis, Lactobacillus plantarum, Lactococcus garvieae, Tetragenococcus halophilus and Weissella thailandensis. In addition, Staphylococcus carnosus was detected in kung-som as minor microflora. These dominant strains would allow the development of defined starter cultures for improving the quality of kung-som.

  4. Om dass-sætninger som afficeret eller efficeret objekt

    DEFF Research Database (Denmark)

    Holsting, Alexandra

    2013-01-01

    Temaet for nærværende artikel er en diskussion af muligheden for at fastlægge en tysk dass-sætnings semantiske funktion som afficeret eller efficeret objekt , når den optræder i rollen som komplement for verber, der har såvel en afficerende som en efficerende betydningsvariant, hvorved dass......-sætningen i det første tilfælde betegner et forhold, matrixsætningens subjektsreferent reagerer på, og i det andet indholdet af en ytring, der fremsættes af matrixsætningens subjektsreferent. Jeg går i artiklen særligt ind i diskussionen om, hvorvidt dass-sætningens modus kan tjene som formel indikation på...... den semantiske funktion, dvs. om en dass-sætning i konjunktiv utvetydigt kan tilskrives en funktion som efficeret objekt for matrixsætningsverbet....

  5. On the Relationship between Variational Level Set-Based and SOM-Based Active Contours

    Science.gov (United States)

    Abdelsamea, Mohammed M.; Gnecco, Giorgio; Gaber, Mohamed Medhat; Elyan, Eyad

    2015-01-01

    Most Active Contour Models (ACMs) deal with the image segmentation problem as a functional optimization problem, as they work on dividing an image into several regions by optimizing a suitable functional. Among ACMs, variational level set methods have been used to build an active contour with the aim of modeling arbitrarily complex shapes. Moreover, they can handle also topological changes of the contours. Self-Organizing Maps (SOMs) have attracted the attention of many computer vision scientists, particularly in modeling an active contour based on the idea of utilizing the prototypes (weights) of a SOM to control the evolution of the contour. SOM-based models have been proposed in general with the aim of exploiting the specific ability of SOMs to learn the edge-map information via their topology preservation property and overcoming some drawbacks of other ACMs, such as trapping into local minima of the image energy functional to be minimized in such models. In this survey, we illustrate the main concepts of variational level set-based ACMs, SOM-based ACMs, and their relationship and review in a comprehensive fashion the development of their state-of-the-art models from a machine learning perspective, with a focus on their strengths and weaknesses. PMID:25960736

  6. Historiens Mening som et Kreativt Produkt - En Analyse av Camille Paglias "The Birth of the Western Eye"

    OpenAIRE

    Kyllingstad, Elisabeth

    2016-01-01

    Dette prosjektet er en metodisk tilnærming til Camille Paglias filosofiske historietekst ”The Birth of the Western Eye”. Sexual Personae – Art and Decadence from Nefertiti to Emily Dickinson (1991) er en revidert versjon av doktorgradsavhendlingen hennes, som hun forsvarte i 1974. Den forteller om det Paglia identifiserer som grunnleggende drivkrefter i det vestlige mennesket, og dets kunstneriske produksjon. På denne måten kan verket leses som en guide gjennom vestlig tenkning så vel som kun...

  7. Får - ett miljövänligt alternativ som ogräsbekämpning

    DEFF Research Database (Denmark)

    Jensen, Anne Mette Dahl; Sintorn, Kim

    2010-01-01

    Erfarenhetsutbyte omkring fårbete som ogräsbekämpning var bland annat på dagordningen då svenska och danska greenkeepers som helt eller delvis sköter sina banor pesticidfritt möttes på Furesö Golfklubb den 4 maj i år.......Erfarenhetsutbyte omkring fårbete som ogräsbekämpning var bland annat på dagordningen då svenska och danska greenkeepers som helt eller delvis sköter sina banor pesticidfritt möttes på Furesö Golfklubb den 4 maj i år....

  8. Applications of Self-Organising Map (SOM) for prioritisation of endemic zones of filariasis in Andhra Pradesh, India.

    Science.gov (United States)

    Murty, Upadhayula Suryanaryana; Rao, Mutheneni Srinivasa; Sriram, K; Rao, K Madhusudhan

    2011-01-01

    Entomological and epidemiological data of Lymphatic Filariasis (LF) was collected from 120 villages of four districts of Andhra Pradesh, India. Self-Organising Maps (SOMs), data-mining techniques, was used to classify and prioritise the endemic zones of filariasis. The results show that, SOMs classified all the villages into three major clusters by considering the data of Microfilaria (MF) rate, infection, infectivity rate and Per Man Hour (PMH). By considering the patterns of cluster, appropriate decision can be drawn for each parameter that is responsible for disease transmission of filariasis. Hence, SOM will certainly be a suitable tool for management of filariasis. The detailed application of SOM is discussed in this paper.

  9. Novel estimation of the humification degree of soil organic matter by laser-induced breakdown spectroscopy

    Energy Technology Data Exchange (ETDEWEB)

    Ferreira, Edilene Cristina, E-mail: edilene@iq.unesp.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); São Paulo State University—UNESP, Analytical Chemistry Department, P.O. Box 355, 14801-970 Rua Prof. Francisco Degni, 55, CEP 14800-900 Araraquara, SP (Brazil); Ferreira, Ednaldo José, E-mail: ednaldo.ferreira@embrapa.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Villas-Boas, Paulino Ribeiro, E-mail: paulino.villas-boas@embrapa.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Senesi, Giorgio Saverio, E-mail: giorgio.senesi@ba.imip.cnr.it [Institute of Inorganic Methodologies and Plasmas, CNR, Bari 70126 (Italy); Carvalho, Camila Miranda, E-mail: camilamc@gmail.com [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Physics Institute of São Carlos, University of São Paulo, IFSC-USP, Av. Trabalhador são-carlense, 400 Pq. Arnold Schimid, 13566-590 São Carlos, SP (Brazil); Romano, Renan Arnon, E-mail: renan.romano@gmail.com [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); Physics Institute of São Carlos, University of São Paulo, IFSC-USP, Av. Trabalhador são-carlense, 400 Pq. Arnold Schimid, 13566-590 São Carlos, SP (Brazil); Martin-Neto, Ladislau, E-mail: ladislau.martin@embrapa.br [Embrapa Instrumentation, Rua XV de Novembro, 1452, CEP 13560-970 São Carlos, SP (Brazil); and others

    2014-09-01

    Soil organic matter (SOM) constitutes an important reservoir of terrestrial carbon and can be considered an alternative for atmospheric carbon storage, contributing to global warming mitigation. Soil management can favor atmospheric carbon incorporation into SOM or its release from SOM to atmosphere. Thus, the evaluation of the humification degree (HD), which is an indication of the recalcitrance of SOM, can provide an estimation of the capacity of carbon sequestration by soils under various managements. The HD of SOM can be estimated by using various analytical techniques including fluorescence spectroscopy. In the present work, the potential of laser-induced breakdown spectroscopy (LIBS) to estimate the HD of SOM was evaluated for the first time. Intensities of emission lines of Al, Mg and Ca from LIBS spectra showing correlation with fluorescence emissions determined by laser-induced fluorescence spectroscopy (LIFS) reference technique were used to obtain a multivaried calibration model based on the k-nearest neighbor (k-NN) method. The values predicted by the proposed model (A-LIBS) showed strong correlation with LIFS results with a Pearson's coefficient of 0.87. The HD of SOM obtained after normalizing A-LIBS by total carbon in the sample showed a strong correlation to that determined by LIFS (0.94), thus suggesting the great potential of LIBS for this novel application. - Highlights: • Humification degree of soil organic matter (HD) • Importance of soil organic matter HD in keeping carbon in soil • Laser induced fluorescence spectroscopy (LIFS) for HD estimation (reference method) • New LIBS application to predict HD.

  10. CQESTR Simulation of Soil Organic Matter Dynamics in Long-term Agricultural Experiments across USA

    Science.gov (United States)

    Gollany, H.; Liang, Y.; Albrecht, S.; Rickman, R.; Follett, R.; Wilhelm, W.; Novak, J.

    2009-04-01

    Soil organic matter (SOM) has important chemical (supplies nutrients, buffers and adsorbs harmful chemical compounds), biological (supports the growth of microorganisms and micro fauna), and physical (improves soil structure and soil tilth, stores water, and reduces surface crusting, water runoff) functions. The loss of 20 to 50% of soil organic carbon (SOC) from USA soils after converting native prairie or forest to production agriculture is well documented. Sustainable management practices for SOC is critical for maintaining soil productivity and responsible utilization of crop residues. As crop residues are targeted for additional uses (e.g., cellulosic ethanol feedstock) developing C models that predict change in SOM over time with change in management becomes increasingly important. CQESTR, pronounced "sequester," is a process-based C balance model that relates organic residue additions, crop management and soil tillage to SOM accretion or loss. The model works on daily time-steps and can perform long-term (100-year) simulations. Soil organic matter change is computed by maintaining a soil C budget for additions, such as crop residue or added amendments like manure, and organic C losses through microbial decomposition. Our objective was to simulate SOM changes in agricultural soils under a range of soil parent materials, climate and management systems using the CQESTR model. Long-term experiments (e.g. Champaign, IL, >100 yrs; Columbia, MO, >100 yrs; Lincoln, NE, 20 yrs) under various tillage practices, organic amendments, crop rotations, and crop residue removal treatments were selected for their documented history of the long-term effects of management practice on SOM dynamics. Simulated and observed values from the sites were significantly related (r2 = 94%, P management issue. CQESTR successfully simulated a substantial decline in SOM with 90% of crop residue removal for 50 years under various rotations at Columbia, MO and Champaign, IL. An increase in SOM

  11. Determining the spatial variability of wetland soil bulk density, organic matter, and the conversion factor between organic matter and organic carbon across coastal Louisiana, U.S.A.

    Science.gov (United States)

    Wang, Hongqing; Piazza, Sarai C.; Sharp, Leigh A.; Stagg, Camille L.; Couvillion, Brady R.; Steyer, Gregory D.; McGinnis, Thomas E.

    2016-01-01

    Soil bulk density (BD), soil organic matter (SOM) content, and a conversion factor between SOM and soil organic carbon (SOC) are often used in estimating SOC sequestration and storage. Spatial variability in BD, SOM, and the SOM–SOC conversion factor affects the ability to accurately estimate SOC sequestration, storage, and the benefits (e.g., land building area and vertical accretion) associated with wetland restoration efforts, such as marsh creation and sediment diversions. There are, however, only a few studies that have examined large-scale spatial variability in BD, SOM, and SOM–SOC conversion factors in coastal wetlands. In this study, soil cores, distributed across the entire coastal Louisiana (approximately 14,667 km2) were used to examine the regional-scale spatial variability in BD, SOM, and the SOM–SOC conversion factor. Soil cores for BD and SOM analyses were collected during 2006–09 from 331 spatially well-distributed sites in the Coastwide Reference Monitoring System network. Soil cores for the SOM–SOC conversion factor analysis were collected from 15 sites across coastal Louisiana during 2006–07. Results of a split-plot analysis of variance with incomplete block design indicated that BD and SOM varied significantly at a landscape level, defined by both hydrologic basins and vegetation types. Vertically, BD and SOM varied significantly among different vegetation types. The SOM–SOC conversion factor also varied significantly at the landscape level. This study provides critical information for the assessment of the role of coastal wetlands in large regional carbon budgets and the estimation of carbon credits from coastal restoration.

  12. Lead sequestration and species redistribution during soil organic matter decomposition

    Science.gov (United States)

    Schroth, A.W.; Bostick, B.C.; Kaste, J.M.; Friedland, A.J.

    2008-01-01

    The turnover of soil organic matter (SOM) maintains a dynamic chemical environment in the forest floor that can impact metal speciation on relatively short timescales. Here we measure the speciation of Pb in controlled and natural organic (O) soil horizons to quantify changes in metal partitioning during SOM decomposition in different forest litters. We provide a link between the sequestration of pollutant Pb in O-horizons, estimated by forest floor Pb inventories, and speciation using synchrotron-based X-ray fluorescence and X-ray absorption spectroscopy. When Pb was introduced to fresh forest Oi samples, it adsorbed primarily to SOM surfaces, but as decomposition progressed over two years in controlled experiments, up to 60% of the Pb was redistributed to pedogenic birnessite and ferrihydrite surfaces. In addition, a significant fraction of pollutant Pb in natural soil profiles was associated with similar mineral phases (???20-35%) and SOM (???65-80%). Conifer forests have at least 2-fold higher Pb burdens in the forest floor relative to deciduous forests due to more efficient atmospheric scavenging and slower organic matter turnover. We demonstrate that pedogenic minerals play an important role in surface soil Pb sequestration, particularly in deciduous forests, and should be considered in any assessment of pollutant Pb mobility. ?? 2008 American Chemical Society.

  13. Effect of soil organic matter on antimony bioavailability after the remediation process

    International Nuclear Information System (INIS)

    Nakamaru, Yasuo Mitsui; Martín Peinado, Francisco José

    2017-01-01

    We evaluated the long-term (18 year) and short-term (4 weeks) changes of Sb in contaminated soil with SOM increase under remediation process. In the Aznalcóllar mine accident (1998) contaminated area, the remediation measurement implemented the Guadiamar Green Corridor, where residual pollution is still detected. Soils of the re-vegetated area (O2) with high pH and high SOM content, moderately re-vegetated area (O1) and unvegetated area (C) were sampled. Soil pH, CEC, SOM amount and soil Sb forms were evaluated. Soil Sb was measured as total, soluble, exchangeable, EDTA extractable, acid oxalate extractable, and pyro-phosphate extractable fractions. Further, the short-term effect of artificial organic matter addition was also evaluated with incubation study by adding compost to the sampled soil from C, O1 and O2 areas. After 4 weeks of incubation, soil chemical properties and Sb forms were evaluated. In re-vegetated area (O2), soil total Sb was two times lower than in unvegetated area (C); however, soluble, exchangeable, and EDTA extractable Sb were 2–8 times higher. The mobile/bioavailable Sb increase was also observed after 4 weeks of incubation with the addition of compost. Soluble, exchangeable, and EDTA extractable Sb was increased 2–4 times by compost addition. By the linear regression analysis, the significantly related factors for soluble, exchangeable, and EDTA extractable Sb values were pH, CEC, and SOM, respectively. Soluble Sb increase was mainly related to pH rise. Exchangeable Sb should be bound by SOM-metal complex and increased with CEC. EDTA extractable fraction should be increased with increase of SOM as SOM-Fe associated Sb complex. From these results, it was shown that increase of SOM under natural conditions or application of organic amendment under remediation process should increase availability of Sb to plants. - Highlights: • The effect of SOM on Sb availability was evaluated after the remediation process. • Increase in SOM raised

  14. Molecular characterization of soil organic matter from native vegetation–pasture–sugarcane transitions in Brazil

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Dener Márcio da Silva, E-mail: denermsoliveira@gmail.com [University of São Paulo, Luiz de Queiroz College of Agriculture, Department of Soil Science, 11 Páduas Dias Avenue, 13418-900 Piracicaba, SP (Brazil); Colorado State University, Natural Resource Ecology Laboratory, 1231 East Drive, 80523-1499 Fort Collins, CO (United States); Schellekens, Judith; Cerri, Carlos Eduardo Pellegrino [University of São Paulo, Luiz de Queiroz College of Agriculture, Department of Soil Science, 11 Páduas Dias Avenue, 13418-900 Piracicaba, SP (Brazil)

    2016-04-01

    Replacing pastures (PA) with sugarcane (SG) has been deemed an agronomically feasible strategy for sugarcane expansion in Brazil. However, there are some uncertainties about the environmental impacts regarding this land use change (LUC), mainly related to soil organic matter (SOM), a key factor of environmental sustainability of Brazilian ethanol. LUC-related losses of SOM can overcome the C savings from biofuels. The molecular composition of SOM was evaluated to understand the C dynamics regarding LUC from PA to SG, using native vegetation (NV) as reference. Our study area was located in the south-central region of Brazil. Soil sampling was performed at three depths (0–0.1 m, 0.2–0.3 m and 0.9–1 m) in three representative sites with known LUC history and management practice since 1970. Pyrolysis–gas chromatography/mass spectrometry (Py–GC/MS) was chosen to study SOM chemistry. Content and isotopic composition of soil organic C and N were also determined. The LUC caused decreases on C and N contents and on δ{sup 13}C isotopic values. Depth was the major factor that influenced SOM composition, while the influence of LUC was mainly evident in surface soils and diminished rapidly with depth. The main difference in SOM composition undergoing the conversion PA-SG was a higher contribution from compounds associated to fresh litter inputs. The high contribution from fresh litter, having a relatively low mean residence time and increasing decomposition rates, is probably a major factor that drives C losses in areas undergoing sugarcane expansion. - Graphical abstract: We chose 3 sites in Brazil (1) and collected soil samples in areas undergoing LUC pasture–sugarcane (2) to evaluate SOM composition using Py–GC/MS (3). The LUC causes shifts on SOM signature (4), highlighting the increase of fresh litter compounds in sugarcane areas (5). - Highlights: • Effect of land use change (LUC) on SOM composition in Brazilian soils • Py-GC/MS of NaOH extractable SOM

  15. 21 CFR 1250.89 - Swimming pools.

    Science.gov (United States)

    2010-04-01

    ... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Swimming pools. 1250.89 Section 1250.89 Food and... SANITATION Sanitation Facilities and Conditions on Vessels § 1250.89 Swimming pools. (a) Fill and draw swimming pools shall not be installed or used. (b) Swimming pools of the recirculation type shall be...

  16. Patent pools: Intellectual property rights and competition.

    NARCIS (Netherlands)

    Rodriguez, V.F.

    2010-01-01

    Patent pools do not correct all problems associated with patent thickets. In this respect, patent pools might not stop the outsider problem from striking pools. Moreover, patent pools can be expensive to negotiate, can exclude patent holders with smaller numbers of patents or enable a group of major

  17. Fermi field and Dirac oscillator in a Som-Raychaudhuri space-time

    Science.gov (United States)

    de Montigny, Marc; Zare, Soroush; Hassanabadi, Hassan

    2018-05-01

    We investigate the relativistic dynamics of a Dirac field in the Som-Raychaudhuri space-time, which is described by a Gödel-type metric and a stationary cylindrical symmetric solution of Einstein field equations for a charged dust distribution in rigid rotation. In order to analyze the effect of various physical parameters of this space-time, we solve the Dirac equation in the Som-Raychaudhuri space-time and obtain the energy levels and eigenfunctions of the Dirac operator by using the Nikiforov-Uvarov method. We also examine the behaviour of the Dirac oscillator in the Som-Raychaudhuri space-time, in particular, the effect of its frequency and the vorticity parameter.

  18. Initial water repellency affected organic matter depletion rates of manure amended soils in Sri Lanka

    Directory of Open Access Journals (Sweden)

    Leelamanie D.A.L.

    2014-12-01

    Full Text Available The wetting rate of soil is a measure of water repellency, which is a property of soils that prevents water from wetting or penetrating into dry soil. The objective of the present research was to examine the initial water repellency of organic manure amended soil, and its relation to the soil organic matter (SOM depletion rates in the laboratory. Soil collected from the Wilpita natural forest, Sri Lanka, was mixed with organic manure to prepare soil samples with 0, 5, 10, 25, and 50% organic manure contents. Locally available cattle manure (CM, goat manure (GM, and Casuarina equisetifolia leaves (CE were used as the organic manure amendments. Organic matter content of soils was measured in 1, 3, 7, 14, and 30 days intervals under the laboratory conditions with 74±5% relative humidity at 28±1°C. Initial water repellency of soil samples was measured as the wetting rates using the water drop penetration time (WDPT test. Initial water repellency increased with increasing SOM content showing higher increasing rate for hydrophobic CE amended samples compared with those amended with CM and GM. The relation between water repellency and SOM content was considered to be governed by the original hydrophobicities of added manures. The SOM contents of all the soil samples decreased with the time to reach almost steady level at about 30 d. The initial SOM depletion rates were negatively related with the initial water repellency. However, all the CE amended samples initially showed prominent low SOM depletion rates, which were not significantly differed with the amended manure content or the difference in initial water repellency. It is explicable that the original hydrophobicity of the manure as well has a potentially important effect on initiation of SOM decomposition. In contrast, the overall SOM depletion rate can be attributed to the initial water repellency of the manure amended sample, however, not to the original hydrophobicity of the amended manure

  19. Filosofisk terapi som træning til døden

    DEFF Research Database (Denmark)

    Dræby, Anders

    Den eksistentielfænomenologiske terapi deler den opfattelse med stoicismen, at filosofiens hovedopgave er at hjælpe mennesket med at finde vej i en problematisk verden. Oplægget udforsker desuden et overlap, som består i den indsigt, at terapeutisk udfrielse fra menneskelig lidelse til livsduelig......Den eksistentielfænomenologiske terapi deler den opfattelse med stoicismen, at filosofiens hovedopgave er at hjælpe mennesket med at finde vej i en problematisk verden. Oplægget udforsker desuden et overlap, som består i den indsigt, at terapeutisk udfrielse fra menneskelig lidelse til...

  20. Surhetsvariasjoner som følge av nedtapping av et regulert vann.

    OpenAIRE

    Selmer-Olsen, A. R.

    1981-01-01

    Det har vært utført analyser og lagringsforsøk med prøver av tørrlagt bunnmateriale fra Trevatn tatt våren 1976. Prøver tatt ute i terrenget om høsten etter en lang tørr sommer viste stort sett samme bilde som prøvene fra våren etter lagring i laboratoriet under aerobe betingelser. Tabell 2 viser hvordan pH og SO4-S varierer med Iagringsbetingelsene. Oksydasjonsprosessene som slikt materiale blir utsatt for ved lufttilgang over et lengre tidsrom kan resultere i utvasking av meget sure forbind...

  1. Djur som en del i omvårdnad : En litteraturstudie

    OpenAIRE

    Jirback, Fia; Olsson, Malin

    2011-01-01

    Bakgrund: Äldre på boende idag kan känna att de saknar sociala interaktioner med vårdpersonal, familj eller vänner. För att uppleva god livskvalitet krävs bland annat trygghet, sociala interaktioner och aktiviteter. Djur kan användas som behandlingsmetod i vården i form av Animal-Assisted Activity (AAA) och Animal-Assisted Therapy (AAT). Syfte: Syftet med litteraturstudien var att belysa sällskapsdjurs betydelse för äldres livskvalitet på äldreboende. Metod: Studien har genomförts som en allm...

  2. From poverty to power? Brasiliansk sosialpolitikk som soft power-ressurs

    OpenAIRE

    Flatjord, Inger-Marie

    2015-01-01

    Grunnet markant fattigdomsreduksjon det siste tiåret, har Brasil gått fra å være det klassiske eksemplet på et land med stor fattigdom og enorme sosiale forskjeller, til å innta en posisjon som foregangsland i den globale utviklingsdiskursen. Landets sosialpolitikk har høstet annerkjennelse fra både FN og Verdensbanken, og Brasil opplever en stor etterspørsel fra utviklingsland som vil lære av landets sosialpolitiske erfaringer. I lys av dette har jeg i denne oppgaven analysert hvordan landet...

  3. Specialet som glasloft – hvorfor får mandlige studerende bedre specialekarakterer?

    Directory of Open Access Journals (Sweden)

    Vibeke Lehmann Nielsen

    2012-03-01

    Full Text Available Selvom de mandlige universitetsstuderende ikke klarer sig bedre end kvinderne frem til specialet, får de gennemsnitligt bedre specialekarakterer. Artiklens analyser viser, at det hverken handler om specialevejlederens køn eller om typen af universitetsstudium. Mulige forklaringer, som det er værd for kommende forskning at forfølge, er dels generel diskrimination af kvindelige specialestuderende og dels de studerendes møde med specialet, hvor kønnenes livssituation og/eller deres reaktioner på rollen som specialestuderende kan være forskellige.

  4. A new design for SLAM front-end based on recursive SOM

    Science.gov (United States)

    Yang, Xuesi; Xia, Shengping

    2015-12-01

    Aiming at the graph optimization-based monocular SLAM, a novel design for the front-end in single camera SLAM is proposed, based on the recursive SOM. Pixel intensities are directly used to achieve image registration and motion estimation, which can save time compared with the current appearance-based frameworks, usually including feature extraction and matching. Once a key-frame is identified, a recursive SOM is used to actualize loop-closure detecting, resulting a more precise location. The experiment on a public dataset validates our method on a computer with a quicker and effective result.

  5. Efficient pooling designs for library screening

    OpenAIRE

    Bruno, William J.; Knill, Emanuel; Balding, David J.; Bruce, D. C.; Doggett, N. A.; Sawhill, W. W.; Stallings, R. L.; Whittaker, Craig C.; Torney, David C.

    1994-01-01

    We describe efficient methods for screening clone libraries, based on pooling schemes which we call ``random $k$-sets designs''. In these designs, the pools in which any clone occurs are equally likely to be any possible selection of $k$ from the $v$ pools. The values of $k$ and $v$ can be chosen to optimize desirable properties. Random $k$-sets designs have substantial advantages over alternative pooling schemes: they are efficient, flexible, easy to specify, require fewer pools, and have er...

  6. EP BICYCLE POOL - VIGNETTES 2002

    CERN Multimedia

    EP-SMI Help Desk

    2002-01-01

    The vignettes (insurance certificates) for 2002 become obligatory from 1 June. If you have a bicycle from the EP Pool, please bring it to the EP-SMI Help Desk (Building 124) on any working day up to 31 May between 8h.30 - 12h.00 or 13h.30 - 17h.30. EP-SMI Help Desk

  7. Sculpting the Barnyard Gene Pool

    Science.gov (United States)

    Childers, Gina; Wolfe, Kim; Dupree, Alan; Young, Sheila; Caver, Jessica; Quintanilla, Ruby; Thornton, Laura

    2016-01-01

    Project-based learning (PBL) takes student engagement to a higher level through reflective collaboration, inquiry, critical thinking, problem solving, and personal relevance. This article explains how six high school teachers developed an interconnected, interdisciplinary STEM-focused PBL called "Sculpting the Barnyard Gene Pool." The…

  8. Changes in labile soil organic matter fractions following land use change from monocropping to poplar-based agroforestry systems in a semiarid region of Northeast China.

    Science.gov (United States)

    Mao, Rong; Zeng, De-Hui; Li, Lu-Jun; Hu, Ya-Lin

    2012-11-01

    Labile fractions of soil organic matter (SOM) respond rapidly to land management practices and can be used as a sensitive indicator of changes in SOM. However, there is little information about the effect of agroforestry practices on labile SOM fractions in semiarid regions of China. In order to test the effects of land use change from monocropping to agroforestry systems on labile SOM fractions, we investigated soil microbial biomass C (MBC) and N, particulate organic matter C (POMC) and N (POMN), as well as total organic C (TOC) and total N (TN) in the 0- to 15-cm and the 15- to 30-cm layers in 4-year-old poplar-based agroforestry systems and adjoining monocropping systems with two different soil textures (sandy loam and sandy clay loam) in a semiarid region of Northeast China. Our results showed that poplar-based agroforestry practices affected soil MBC, POMC, and POMN, albeit there was no significant difference in TOC and TN. Agroforestry practices increased MBC, POMC, and POMN in sandy clay loam soils. However, in sandy loam soils, agroforestry practices only increased MBC and even decreased POMC and POMN at the 0- to 15-cm layer. Our results suggest that labile SOM fractions respond sensitively to poplar-based agroforestry practices and can provide early information about the changes in SOM in semiarid regions of Northeast China and highlight that the effects of agroforestry practices on labile SOM fractions vary with soil texture.

  9. Engineering soil organic matter quality: Biodiesel Co-Product (BCP) stimulates exudation of nitrogenous microbial biopolymers

    Science.gov (United States)

    Redmile-Gordon, Marc A.; Evershed, Richard P.; Kuhl, Alison; Armenise, Elena; White, Rodger P.; Hirsch, Penny R.; Goulding, Keith W.T.; Brookes, Philip C.

    2015-01-01

    Biodiesel Co-Product (BCP) is a complex organic material formed during the transesterification of lipids. We investigated the effect of BCP on the extracellular microbial matrix or ‘extracellular polymeric substance’ (EPS) in soil which is suspected to be a highly influential fraction of soil organic matter (SOM). It was hypothesised that more N would be transferred to EPS in soil given BCP compared to soil given glycerol. An arable soil was amended with BCP produced from either 1) waste vegetable oils or 2) pure oilseed rape oil, and compared with soil amended with 99% pure glycerol; all were provided with 15N labelled KNO3. We compared transfer of microbially assimilated 15N into the extracellular amino acid pool, and measured concomitant production of exopolysaccharide. Following incubation, the 15N enrichment of total hydrolysable amino acids (THAAs) indicated that intracellular anabolic products had incorporated the labelled N primarily as glutamine and glutamate. A greater proportion of the amino acids in EPS were found to contain 15N than those in the THAA pool, indicating that the increase in EPS was comprised of bioproducts synthesised de novo. Moreover, BCP had increased the EPS production efficiency of the soil microbial community (μg EPS per unit ATP) up to approximately double that of glycerol, and caused transfer of 21% more 15N from soil solution into EPS-amino acids. Given the suspected value of EPS in agricultural soils, the use of BCP to stimulate exudation is an interesting tool to consider in the theme of delivering sustainable intensification. PMID:26635420

  10. Effect of selection of pH in swimming pool on formation of chlorination by-products

    DEFF Research Database (Denmark)

    Hansen, Kamilla Marie Speht; Willach, Sarah; Mosbæk, Hans

    2011-01-01

    Chlorine is used as disinfection agent in public swimming pools, but also reacts with organic matter in the water forming chlorinat ed disinfection by-products. In order to evaluate the effect of choice of pHsetpoint in the pool we investigated the effect of chlorination of artificial body fluid...

  11. Infiltrationsanæstesi som postoperativ smertebehandling ved hoftenær femurfraktur - et igangværende studie

    DEFF Research Database (Denmark)

    Bech, Rune Dueholm

    2008-01-01

    pertrochantær femurfraktur og collum femoris fraktur inkluderes. 50 patienter indgår i hver af de to diagnose-grupper (to delstudier). Ved randomisering tildeles patienterne hhv. Ropivacain eller placebo (NaCl), der gives som 1 peroperativ og 6 postoperative bolusinstillationer via et kateter, som fjernes efter...

  12. Use of photoacoustic mid-infrared spectroscopy to characterize soil properties and soil organic matter stability

    Science.gov (United States)

    Peltre, Clement; Bruun, Sander; Du, Changwen; Stoumann Jensen, Lars

    2014-05-01

    The persistence of soil organic matter (SOM) is recognized as a major ecosystem property due to its key role in earth carbon cycling, soil quality and ecosystem services. SOM stability is typically studied using biological methods such as measuring CO2-C evolution from microbial decomposition of SOM during laboratory incubation or by physical or chemical fractionation methods, allowing the separation of a labile fraction of SOM. However these methods are time consuming and there is still a need for developing reliable techniques to characterize SOM stability, providing both quantitative measurements and qualitative information, in order to improve our understanding of the mechanisms controlling SOM persistence. Several spectroscopic techniques have been used to characterize and predict SOM stability, such as near infrared reflectance spectroscopy (NIRS) and diffuse reflectance mid-infrared spectroscopy (DRIFT). The latter allows a proper identification of spectral regions corresponding to vibrations of specific molecular or functional groups associated with SOM lability. However, reflectance spectroscopy for soil analyses raises some difficulties related to the low reflectance of soils, and to the high influence of particle size. In the last three decades, the progresses in microphone sensitivity dramatically increased the performance of photoacoustic Fourier transform mid-infrared spectroscopy (FTIR-PAS). This technique offers benefits over reflectance spectroscopy techniques, because particle size and the level of sample reflectance have little effect of on the PAS signal, since FTIR-PAS is a direct absorption technique. Despite its high potential for soil analysis, only a limited number of studies have so far applied FTIR-PAS for soil characterization and its potential for determining SOM degradability still needs to be investigated. The objective of this study was to assess the potential of FTIR-PAS for the characterization of SOM decomposability during

  13. Effect of soil organic matter on antimony bioavailability after the remediation process.

    Science.gov (United States)

    Nakamaru, Yasuo Mitsui; Martín Peinado, Francisco José

    2017-09-01

    We evaluated the long-term (18 year) and short-term (4 weeks) changes of Sb in contaminated soil with SOM increase under remediation process. In the Aznalcóllar mine accident (1998) contaminated area, the remediation measurement implemented the Guadiamar Green Corridor, where residual pollution is still detected. Soils of the re-vegetated area (O2) with high pH and high SOM content, moderately re-vegetated area (O1) and unvegetated area (C) were sampled. Soil pH, CEC, SOM amount and soil Sb forms were evaluated. Soil Sb was measured as total, soluble, exchangeable, EDTA extractable, acid oxalate extractable, and pyro-phosphate extractable fractions. Further, the short-term effect of artificial organic matter addition was also evaluated with incubation study by adding compost to the sampled soil from C, O1 and O2 areas. After 4 weeks of incubation, soil chemical properties and Sb forms were evaluated. In re-vegetated area (O2), soil total Sb was two times lower than in unvegetated area (C); however, soluble, exchangeable, and EDTA extractable Sb were 2-8 times higher. The mobile/bioavailable Sb increase was also observed after 4 weeks of incubation with the addition of compost. Soluble, exchangeable, and EDTA extractable Sb was increased 2-4 times by compost addition. By the linear regression analysis, the significantly related factors for soluble, exchangeable, and EDTA extractable Sb values were pH, CEC, and SOM, respectively. Soluble Sb increase was mainly related to pH rise. Exchangeable Sb should be bound by SOM-metal complex and increased with CEC. EDTA extractable fraction should be increased with increase of SOM as SOM-Fe associated Sb complex. From these results, it was shown that increase of SOM under natural conditions or application of organic amendment under remediation process should increase availability of Sb to plants. Copyright © 2017 Elsevier Ltd. All rights reserved.

  14. Investigating microbial transformations of soil organic matter: synthesizing knowledge from disparate fields to guide new experimentation

    Science.gov (United States)

    Billings, S. A.; Tiemann, L. K.; Ballantyne, F., IV; Lehmeier, C. A.; Min, K.

    2015-04-01

    Discerning why some soil organic matter (SOM) leaves soil profiles relatively quickly while other compounds, especially at depth, can be retained for decades to millennia is challenging for a multitude of reasons. Simultaneous with soil-specific advances, multiple other disciplines have enhanced their knowledge bases in ways potentially useful for future investigations of SOM decay. In this article, we highlight observations highly relevant for those investigating SOM decay and retention but often emanating from disparate fields and residing in literature seldom cited in SOM research. We focus on recent work in two key areas. First, we turn to experimental approaches using natural and artificial aquatic environments to investigate patterns of microbially mediated OM transformations as environmental conditions change, and highlight how aquatic microbial responses to environmental change can reveal processes likely important to OM decay and retention in soils. Second, we emphasize the importance of establishing intrinsic patterns of decay kinetics for purified substrates commonly found in soils to develop baseline rates. These decay kinetics - which represent the upper limit of the reaction rates - can then be compared to substrate decay kinetics observed in natural samples, which integrate intrinsic decay reaction rates and edaphic factors essential to the site under study but absent in purified systems. That comparison permits the site-specific factors to be parsed from the fundamental decay kinetics, an important advance in our understanding of SOM decay (and thus persistence) in natural systems. We then suggest ways in which empirical observations from aquatic systems and purified substrate-enzyme reaction kinetics can be used to advance recent theoretical efforts in SOM-focused research. Finally, we suggest how the observations in aquatic and purified substrate-enzyme systems could be used to help unravel the puzzles presented by oft-observed patterns of SOM

  15. "Vi har ikke noget at sige, men vi gør det så koncentreret som muligt"

    DEFF Research Database (Denmark)

    Hansen, Kamma Overgaard

    mellemposition mellem på den ene side Arthur C. Dantos udråbelse af postmodernismen som The End of Art og Fredric Jamesons kritiske udlægning af den postmoderne kunst som simulerende og hans begrædelse af en tabt autenticitet - og på den anden side Linda Hutcheons langt mere positive definering af det...... postmoderne som ironisk og parodisk og dermed nytænkende og metareflekterende. Herudfra karakteriserer jeg De Unge Vilde som ironikere ud fra Søren Kierkegaards karakteristisk af ironikeren som en mellemfase mellem det æstetiske og det etiske livsstadie. Videre argumenterer jeg for, at Dantos ’end of art...

  16. Changes in SOM composition and stability to microbial degradation over time in response to wood chip ash fertilisation

    DEFF Research Database (Denmark)

    Hansen, Mette; Saarsalmi, Anna; Peltre, Clement

    2016-01-01

    spectroscopy (FTIR-PAS) analysis of bulk soil samples. Ash fertilisation of forest soils affected SOM composition in the O-horizon, but not in the top 5 cm of the mineral soil. The pH and biodegradability of SOM were increased in the O-horizon. The changes in SOM composition consisted of enrichment of Fe...... in Denmark, where ash had been spread at different times. Changes in SOM biodegradability were estimated based on an incubation experiment, expressed as percentage of initial carbon. Changes in SOM composition were characterised using thermal analysis and Fourier transform mid-infrared photoacoustic......- and Al-oxides/hydroxides, depletion of carboxylic and aromatic groups and lower thermal stability in soils with older and greater ash application. Ash fertilisation increased soil pH, either right after ash application or through a buffering effect of the ash on acidification caused by decomposing...

  17. Skrivehandlinger som redskab til klar faglig formidling på PharmaSchool

    DEFF Research Database (Denmark)

    Laursen, Katja Årosin

    2016-01-01

    Denne artikel beskriver et pilotprojekt fra 2013, som havde til formål at øge opmærksomheden på klar skriftlig faglig formidling hos undervisere og studerende i kurset Dynamisk Biokemi på PharmaSchool ved Københavns Universitet (KU). På baggrund af en grundig behovsafdækning udviklede en akademisk...

  18. Velfærdsteknologi og læringsteknologi med MOOC som eksempel

    DEFF Research Database (Denmark)

    Helms, Niels Henrik; Heilesen, Simon

    2015-01-01

    Kapitlet redegører for ‘Velfærdsteknologi’ i forhold til begrebet 'læringsteknologi’. Læringsteknologi bestemmes som velfærdsteknologi udfoldet inden for uddannelsessystemet. Ligesom velfærdsteknologi indføres læringsteknologi med multiple dagsordener, hvor hensigterne både er at tilskynde den læ...

  19. Kombineret laser Doppler flowmetri og spectrophotometri som metode til vurdering af mikrocirculation

    DEFF Research Database (Denmark)

    Berggren Olsen, Mette; Sørensen, Hanne Birke; Houlind, Kim Christian

    Kombineret laser Doppler flowmetri og spectrophotometri som metode til vurdering af mikrocirculation Berggren, MB, reservelæge, Karkirurgisk Afdeling, Kolding, mette.marie.berggren.olsen@slb.regionsyddanmark.dk; Houlind, K, lektor, afdelingslæge, Ph.d., Karkirurgisk afdeling, Kolding, kim...

  20. Det moderne projekt – og portfolioen som en af mange succesteknologier

    DEFF Research Database (Denmark)

    Helms, Niels Henrik

    2010-01-01

    I artiklen diskuteres portfolioen i lyset af den canadiske fi losof Taylors begreber om rationel selvkontrol og ekspressiv artikulering som forskellige udtryk for det moderne. En række pædagogiske succesteknologier problematiseres og afsluttende foreslås en kommunitarisk forståelse af det...

  1. Er internethandel kommet for at blive? Eller er det bare krisen som kradser?

    DEFF Research Database (Denmark)

    Ivang, Reimer

    2012-01-01

    I de seneste dage har Jyllandsposten sat fokus på, at omsætningen i den danske detailhandel falder, der fyres, der spares, og det bliver endnu værre i de kommende måneder og år. I artiklen udråbes finanskrisen, som den store skurk, men er det nu den fulde sandhed?...

  2. Arbejdsmiljøseminarer som en metode til at skabe motivation, ansvar og ejerskab til sikkerhedsarbejdet

    DEFF Research Database (Denmark)

    Pedersen, Louise

    2011-01-01

    arbejdsmiljøseminarer som en ny metode til på en meningsfuld måde systematisk at involvere mellemlederne og de ansatte i virksomhedernes sikkerhedsarbejde og dermed potentielt at fremme deres motivation, ansvar og ejerskab til dette. Arbejdsmiljøseminarer tager udgangspunkt i de ansattes faglige ekspertise og...

  3. Det retlige sprog som virkelighedsskabende - graviditetsvært kontra surrogatmoder

    DEFF Research Database (Denmark)

    Pedersen, Frank Høgholm

    2018-01-01

    I dag er det undtagelsen, at kvinden, der bærer graviditeten og føder barnet i et surrogati-arrangement, er genetisk relateret til barnet. I artiklen foreslås som en supplerende betegnelse til surrogatmoder derfor betegnelsen: graviditetsvært. Valget af en retlig betegnelse til beskrivelse af fak...

  4. Teamcoaching som kvalificering af Cooperative Learning på læreruddannelsen

    DEFF Research Database (Denmark)

    Madsen, Henrik

    2008-01-01

    Projektet tager med et systemisk udgangspunkt et blik på coachingens muligheder som kvalificerende redskab for de studerendes tilegnelse af teoretiske og praktiske færdigheder i udviklingen af Cooperative Learning. Der er et teoretisk udgangspunkt i Luhmann og Vygotsky ligesom forskellige stadier i...... udviklingen fra gruppe til team skildres....

  5. SINs and SOMs: Neural microcircuits for size tuning in the zebrafish and mouse visual pathway.

    Directory of Open Access Journals (Sweden)

    Alison J. Barker

    2013-05-01

    Full Text Available In many animals, a fast and reliable circuit for discriminating between predator-sized objects and edible (prey-sized objects is necessary for survival. How are receptive fields in visual brain areas organized to extract information about size? Recent studies from the zebrafish optic tectum and the mouse visual cortex suggest de novo shaping of receptive fields by subtypes of inhibitory neurons. Del Bene et al. (2010 describe a population of GABAergic neurons in the zebrafish optic tectum (Superficial Interneurons, SINs that are necessary for size filtering during prey capture. Adesnik et al. (2012 describe a somatostatin-expressing interneuron population (SOMs that confers surround suppression on layer II/III pyramidal cells in mouse V1. Strikingly both the SINs and the SOMs, display size-dependent response properties. Increasing visual stimulus size increases excitatory input to these neurons. Dampening SIN or SOM activity alters tuning of neighboring circuits such that they lose preference for small objects. Both results provide exciting evidence for mechanisms of size filtering in visual circuits. Here we review the roles of the SINs and the SOMs and speculate on the similarity of such spatial filters across species.

  6. Dark Matter

    Directory of Open Access Journals (Sweden)

    Einasto J.

    2011-06-01

    Full Text Available I give a review of the development of the concept of dark matter. The dark matter story passed through several stages from a minor observational puzzle to a major challenge for theory of elementary particles. Modern data suggest that dark matter is the dominant matter component in the Universe, and that it consists of some unknown non-baryonic particles. Dark matter is the dominant matter component in the Universe, thus properties of dark matter particles determine the structure of the cosmic web.

  7. The origin of soil organic matter dictates its composition and bioreactivity across a mesic boreal forest latitudinal gradient

    Science.gov (United States)

    Kohl, Lukas; Philben, Michael; Edwards, Kate A.; Podrebarac, Frances A.; Warren, Jamie; Ziegler, Susan E.

    2017-04-01

    Climate transect studies and soil warming experiments have shown that soil organic matter (SOM) formed under a warmer climate is typically more resistant to microbial decomposition, as indicated by lower decomposition rates at a given temperature (bioreactivity). However, it remains unclear how climate impacts SOM via its effect on vegetation and thus litter inputs to soils, or on decomposition and thus how SOM changes over time (diagenesis). We addressed this question by studying how the chemical and biological properties of SOM vary with decomposition (depth) and climate history (latitude) in mesic boreal forests of Atlantic Canada. SOM bioreactivity, measured in a 15-months decomposition experiment, decreased from cold to warm regions, and from the topmost (L) to the deepest horizon studied (H). The variations in SOM bioreactivity with climate history and depth, however, were associated with distinct parameters of SOM chemistry. More decomposed SOM with depth was associated with lower proportions of %N as total hydrolysable amino acids (THAA), and a different THAA-based degradation index signifying a more degraded state. However, SOM from the warmer region exhibited higher lignin to carbohydrate ratios, as detected by NMR. None of the measured parameters associated with regional differences in SOM chemistry increased with depth. Together, these results indicate that the regional differences in SOM chemistry and bioreactivity in these soils did not result from significant differences in the degree of degradation, but rather resulted from chemically distinct litter inputs. The comparison of SOM and plant litter chemistry allowed us to identify how climate affects litter inputs in these forests. Vascular plant litter collected in litter traps, unlike SOM, exhibited largely similar chemical composition across all transect regions. Litter traps, however, do not collect moss litter, which is chemically distinct from vascular plant litter. We, therefore, assessed the

  8. Long-term variation in above and belowground plant inputs alters soil organic matter biogeochemistry at the molecular-level

    Science.gov (United States)

    Simpson, M. J.; Pisani, O.; Lin, L.; Lun, O.; Simpson, A.; Lajtha, K.; Nadelhoffer, K. J.

    2015-12-01

    The long-term fate of soil carbon reserves with global environmental change remains uncertain. Shifts in moisture, altered nutrient cycles, species composition, or rising temperatures may alter the proportions of above and belowground biomass entering soil. However, it is unclear how long-term changes in plant inputs may alter the composition of soil organic matter (SOM) and soil carbon storage. Advanced molecular techniques were used to assess SOM composition in mineral soil horizons (0-10 cm) after 20 years of Detrital Input and Removal Treatment (DIRT) at the Harvard Forest. SOM biomarkers (solvent extraction, base hydrolysis and cupric (II) oxide oxidation) and both solid-state and solution-state nuclear magnetic resonance (NMR) spectroscopy were used to identify changes in SOM composition and stage of degradation. Microbial activity and community composition were assessed using phospholipid fatty acid (PLFA) analysis. Doubling aboveground litter inputs decreased soil carbon content, increased the degradation of labile SOM and enhanced the sequestration of aliphatic compounds in soil. The exclusion of belowground inputs (No roots and No inputs) resulted in a decrease in root-derived components and enhanced the degradation of leaf-derived aliphatic structures (cutin). Cutin-derived SOM has been hypothesized to be recalcitrant but our results show that even this complex biopolymer is susceptible to degradation when inputs entering soil are altered. The PLFA data indicate that changes in soil microbial community structure favored the accelerated processing of specific SOM components with littler manipulation. These results collectively reveal that the quantity and quality of plant litter inputs alters the molecular-level composition of SOM and in some cases, enhances the degradation of recalcitrant SOM. Our study also suggests that increased litterfall is unlikely to enhance soil carbon storage over the long-term in temperate forests.

  9. "Ripples" in an Aluminum Pool?

    Science.gov (United States)

    Rohr, James; Wang, Si-Yin; Nesterenko, Vitali F.

    2018-05-01

    Our motivation for this article is for students to realize that opportunities for discovery are all around them. Discoveries that can still puzzle present day researchers. Here we explore an observation by a middle school student concerning the production of what appears to be water-like "ripples" produced in aluminum foil when placed between two colliding spheres. We both applaud and explore the student's reasoning that the ripples were formed in a melted aluminum pool.

  10. Ectomycorrhizal fungi decompose soil organic matter using oxidative mechanisms adapted from saprotrophic ancestors.

    Science.gov (United States)

    Shah, Firoz; Nicolás, César; Bentzer, Johan; Ellström, Magnus; Smits, Mark; Rineau, Francois; Canbäck, Björn; Floudas, Dimitrios; Carleer, Robert; Lackner, Gerald; Braesel, Jana; Hoffmeister, Dirk; Henrissat, Bernard; Ahrén, Dag; Johansson, Tomas; Hibbett, David S; Martin, Francis; Persson, Per; Tunlid, Anders

    2016-03-01

    Ectomycorrhizal fungi are thought to have a key role in mobilizing organic nitrogen that is trapped in soil organic matter (SOM). However, the extent to which ectomycorrhizal fungi decompose SOM and the mechanism by which they do so remain unclear, considering that they have lost many genes encoding lignocellulose-degrading enzymes that are present in their saprotrophic ancestors. Spectroscopic analyses and transcriptome profiling were used to examine the mechanisms by which five species of ectomycorrhizal fungi, representing at least four origins of symbiosis, decompose SOM extracted from forest soils. In the presence of glucose and when acquiring nitrogen, all species converted the organic matter in the SOM extract using oxidative mechanisms. The transcriptome expressed during oxidative decomposition has diverged over evolutionary time. Each species expressed a different set of transcripts encoding proteins associated with oxidation of lignocellulose by saprotrophic fungi. The decomposition 'toolbox' has diverged through differences in the regulation of orthologous genes, the formation of new genes by gene duplications, and the recruitment of genes from diverse but functionally similar enzyme families. The capacity to oxidize SOM appears to be common among ectomycorrhizal fungi. We propose that the ancestral decay mechanisms used primarily to obtain carbon have been adapted in symbiosis to scavenge nutrients instead. © 2015 The Authors. New Phytologist © 2015 New Phytologist Trust.

  11. Sustainability of common pool resources.

    Science.gov (United States)

    Timilsina, Raja Rajendra; Kotani, Koji; Kamijo, Yoshio

    2017-01-01

    Sustainability has become a key issue in managing natural resources together with growing concerns for capitalism, environmental and resource problems. We hypothesize that the ongoing modernization of competitive societies, which we refer to as "capitalism," affects human nature for utilizing common pool resources, thus compromising sustainability. To test this hypothesis, we design and implement a set of dynamic common pool resource games and experiments in the following two types of Nepalese areas: (i) rural (non-capitalistic) and (ii) urban (capitalistic) areas. We find that a proportion of prosocial individuals in urban areas is lower than that in rural areas, and urban residents deplete resources more quickly than rural residents. The composition of proself and prosocial individuals in a group and the degree of capitalism are crucial in that an increase in prosocial members in a group and the rural dummy positively affect resource sustainability by 65% and 63%, respectively. Overall, this paper shows that when societies move toward more capitalistic environments, the sustainability of common pool resources tends to decrease with the changes in individual preferences, social norms, customs and views to others through human interactions. This result implies that individuals may be losing their coordination abilities for social dilemmas of resource sustainability in capitalistic societies.

  12. Flashing oscillation in pool water

    International Nuclear Information System (INIS)

    Takamasa, Tomoji; Kondo, Koichi; Hazuku, Tatsuya

    1996-01-01

    This paper presents an experimental study of high-pressure saturated water discharging into the pool water. The purpose of the experiment is to clarify the phenomena that occur in blow-down of high-pressure saturated water from the pressure vessel into the water-filled containment in the case of a wall-crack accident or a LOCA in an advanced reactor. The results revealed that a flashing oscillation (FO) occurs when high-pressure saturated water discharges into the pool water, under specified experimental settings. The range of the flashing oscillates between a point very close to and some distance from the vent hole. The pressures in the vent tube and pool water vary according to the flashing oscillation. The pressure oscillation and frequency of flashing position might be caused by the balancing action between the supply of saturated water, flashing at the control volume and its condensation on the steam-water interface. A linear analysis was conducted using a spherical flashing bubble model. The period of the flashing oscillation in the experiments can be explained by theoretical analysis

  13. Pressure supression pool thermal mixing

    International Nuclear Information System (INIS)

    Cook, D.H.

    1984-10-01

    A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model developed in this work produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing is verified by comparing the model-predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

  14. Pressure suppression pool thermal mixing

    International Nuclear Information System (INIS)

    Cook, D.H.

    1984-01-01

    A model is developed and verified to describe the thermal mixing that occurs in the pressure suppression pool (PSP) of a commercial BWR. The model is designed specifically for a Mark-I containment and is intended for use in severe accident sequence analyses. The model produces space and time dependent temperature results throughout the PSP and is useful for evaluating the bulk PSP thermal mixing, the condensation effectiveness of the PSP, and the long-term containment integrity. The model is designed to accommodate single or multiple discharging T-quenchers, a PSP circumferential circulation induced by the residual heat removal system discharge, and the thermal stratification of the pool that occurs immediately after the relief valves close. The PSP thermal mixing model is verified by comparing the model predicted temperatures to experimental temperatures that were measured in an operating BWR suppression pool. The model is then used to investigate several PSP thermal mixing problems that include the time to saturate at full relief valve flow, the temperature response to a typical stuck open relief valve scenario, and the effect of operator rotation of the relief valve discharge point

  15. Predicting soil particle density from clay and soil organic matter contents

    DEFF Research Database (Denmark)

    Schjønning, Per; McBride, R.A.; Keller, T.

    2017-01-01

    Soil particle density (Dp) is an important soil property for calculating soil porosity expressions. However, many studies assume a constant value, typically 2.65Mgm−3 for arable, mineral soils. Fewmodels exist for the prediction of Dp from soil organic matter (SOM) content. We hypothesized...

  16. Mean residence time of kaolinite and smectite-bound organic matter in mozambiquan soils

    NARCIS (Netherlands)

    Wattel-Koekkoek, E.J.W.; Buurman, P.

    2004-01-01

    To gain understanding about the process of global warming, it is essential to study the global C cycle. In the global C cycle, soil organic matter (SOM) is a major source and sink of atmospheric C. Turnover times of C in these soil organic compounds vary from hours to thousands of years. Clay

  17. Organic matter dynamics in an intensive dairy production system on a Dutch Spodosol

    NARCIS (Netherlands)

    Verloop, J.; Hilhorst, G.J.; Pronk, A.A.; Sebek, L.B.; Keulen, van H.; Janssen, B.H.; Ittersum, van M.K.

    2015-01-01

    In many studies, possibilities are being explored to adjust farm management to increase or maintain soil organic matter (SOM) contents in agricultural soils. Some options may be conflicting with efficient nutrient (N and P) management, i.e. management aiming at maximum conversion of imported

  18. Management of organic matter in the tropics: Translating theory into practice

    NARCIS (Netherlands)

    Palm, C.A.; Giller, K.E.; Mafongoya, P.L.; Swift, M.J.

    2001-01-01

    Inputs of organic materials play a central role in the productivity of many tropical farming systems by providing nutrients through decomposition and substrate for synthesis of soil organic matter (SOM). The organic inputs in many tropical farming systems such as crop residues, manures, and natural

  19. Potential for Increasing Soil Nutrient Availability via Soil Organic Matter Improvement Using Pseudo Panel Data

    NARCIS (Netherlands)

    Chavez Clemente, M.D.; Berentsen, P.B.M.; Oenema, O.; Oude Lansink, A.G.J.M.

    2014-01-01

    Fixed and random effect models were applied to a pseudo-panel data built of soil analysis reports from tobacco farms to analyze relationships between soil characteristics like soil organic matter (SOM) and soil nitrogen (N), phosphorous (P) and potassium (K) and to explore the potential for

  20. Stabilization and destabilization of soil organic matter--a new focus

    Science.gov (United States)

    Phillip Sollins; Chris Swanston; Marc Kramer

    2007-01-01

    Interest in soil organic matter (SOM) is ramping up as concern mounts about steadily increasing levels of atmospheric CO2. There are two reasons for this. First, there is hope that improvements in crop, forest, and soil management may allow significant amounts of CO2 to be removed from the atmosphere and sequestered in soil...

  1. Soil organic matter stabilization in buried paleosols of the Great Plains

    Science.gov (United States)

    Chaopricha, N. T.; Marin-Spiotta, E.; Mason, J. A.; Mueller, C. W.

    2010-12-01

    Understanding the mechanisms that control soil organic matter (SOM) stabilization is important for understanding how soil carbon is sequestered over millennia, and for predicting how future disturbances may affect soil carbon stocks. We are studying the mechanisms controlling SOM stabilization in the Brady Soil, a buried paleosol in Holocene loess deposits spanning much of the central Great Plains of the United States. The Brady Soil developed 9,000-13,500 years ago during a time of warming and drying that resulted in a shift from C3 to C4 dominated plants. The Brady soil is unusual in that it has very dark coloring, although it contains less than separate particulate organic matter associated with minerals from that within and outside of soil aggregates. We found the largest and darkest amounts of organic C in aggregate-protected SOM greater than 20 µm in diameter. Density and textural fractionation revealed that much of the SOM is bound within aggregates, indicating that protection within aggregates is a major contributor to SOM- stabilization in the Brady Soil. We are conducting a long-term lab soil incubation with soils collected from the modern A horizon and the Brady Soil to determine if the buried SOM becomes microbially available when exposed to the modern atmosphere. We are measuring potential rates of respiration and production of CH4 and N2O. Results so far show respiration rates at field moisture for both modern and buried horizons are limited by water, suggesting dry environmental conditions may have helped to preserve SOM in the Brady Soil. We are investigating the potential for chemical stabilization of the dark SOM preserved in the buried paleosol by characterizing C chemistry using solid-state 13C-NMR spectroscopy. Furthermore, we plan to use lipid analyses and pyrolysis GC/MS to determine likely sources for the SOM: microbial vs plant. Combining information on the physical location of SOM in the soil, its chemical composition, decomposability

  2. Occurrence and simulation of trihalomethanes in swimming pool water: A simple prediction method based on DOC and mass balance.

    Science.gov (United States)

    Peng, Di; Saravia, Florencia; Abbt-Braun, Gudrun; Horn, Harald

    2016-01-01

    Trihalomethanes (THM) are the most typical disinfection by-products (DBPs) found in public swimming pool water. DBPs are produced when organic and inorganic matter in water reacts with chemical disinfectants. The irregular contribution of substances from pool visitors and long contact time with disinfectant make the forecast of THM in pool water a challenge. In this work occurrence of THM in a public indoor swimming pool was investigated and correlated with the dissolved organic carbon (DOC). Daily sampling of pool water for 26 days showed a positive correlation between DOC and THM with a time delay of about two days, while THM and DOC didn't directly correlate with the number of visitors. Based on the results and mass-balance in the pool water, a simple simulation model for estimating THM concentration in indoor swimming pool water was proposed. Formation of THM from DOC, volatilization into air and elimination by pool water treatment were included in the simulation. Formation ratio of THM gained from laboratory analysis using native pool water and information from field study in an indoor swimming pool reduced the uncertainty of the simulation. The simulation was validated by measurements in the swimming pool for 50 days. The simulated results were in good compliance with measured results. This work provides a useful and simple method for predicting THM concentration and its accumulation trend for long term in indoor swimming pool water. Copyright © 2015 Elsevier Ltd. All rights reserved.

  3. Stabilization of enzymatically polymerized phenolic chemicals in a model soil organic matter-free geomaterial.

    Science.gov (United States)

    Palomo, Mónica; Bhandari, Alok

    2012-01-01

    A variety of remediation methods, including contaminant transformation by peroxidase-mediated oxidative polymerization, have been proposed to manage soils and groundwater contaminated with chlorinated phenols. Phenol stabilization has been successfully observed during cross polymerization between phenolic polymers and soil organic matter (SOM) for soils with SOM >3%. This study evaluates peroxidase-mediated transformation and removal of 2,4-dichlorophenol (DCP) from an aqueous phase in contact with a natural geomaterial modified to contain negligible (soils with higher SOM. The SOM-free sorbent was generated by removing SOM using a NaOCl oxidation. When horseradish peroxidase (HRP) was used to induce polymerization of DCP, the soil-water phase distribution relationship (PDR) of DCP polymerization products (DPP) was complete within 1 d and PDRs did not significantly change over the 28 d of study. The conversion of DCP to DPP was close to 95% efficient. Extractable solute consisted entirely of DPP with 5% or less of unreacted DCP. The aqueous extractability of DPP from SOM-free geomaterial decreased at longer contact times and at smaller residual aqueous concentrations of DPP. DCP stabilization appeared to have resulted from a combination of sorption, precipitation, and ligand exchange between oligomeric products and the exposed mineral surfaces. Modification of the mineral surface through coverage with DPP enhanced the time-dependent retention of the oligomers. DPP stabilization in SOM-free geomaterial was comparable with that reported in the literature with soil containing SOM contents >1%. Results from this study suggest that the effectiveness of HRP-mediated stabilization of phenolic compounds not only depends on the cross-coupling with SOM, but also on the modification of the surface of the sorbent that can augment affinity with oligomers and enhance stabilization. Coverage of the mineral surface by phenolic oligomers may be analogous to SOM that can potentially

  4. SOIL NITROGEN TRANSFORMATIONS AND ROLE OF LIGHT FRACTION ORGANIC MATTER IN FOREST SOILS

    Science.gov (United States)

    Depletion of soil organic matter through cultivation may alter substrate availability for microbes, altering the dynamic balance between nitrogen (N) immobilization and mineralization. Soil light fraction (LF) organic matter is an active pool that decreases upon cultivation, and...

  5. CDC Study Finds Fecal Contamination in Pools

    Science.gov (United States)

    ... Communication (404) 639-3286 CDC study finds fecal contamination in pools A study of public pools done ... The E. coli is a marker for fecal contamination. Finding a high percentage of E. coli-positive ...

  6. Study of the trace metal ion influence on the turnover of soil organic matter in cultivated contaminated soils

    International Nuclear Information System (INIS)

    Dumat, C.; Quenea, K.; Bermond, A.; Toinen, S.; Benedetti, M.F.

    2006-01-01

    The role of metals in the behaviour of soil organic matter (SOM) is not well documented. Therefore, we investigated the influence of metals (Pb, Zn, Cu and Cd) on the dynamic of SOM in contaminated soils where maize (C 4 plant) replaced C 3 cultures. Three pseudogley brown leached soil profiles under maize with a decreasing gradient in metals concentrations were sampled. On size fractions, stable carbon isotopic ratio (δ 13 C), metals, organic carbon and nitrogen concentrations were measured in function of depth. The determined sequence for the amount of C 4 organic matter in the bulk fractions: M 3 (0.9) > M 2 (0.4) > M 1 (0.3) is in agreement with a significant influence of metals on the SOM turnover. New C 4 SOM, mainly present in the labile coarser fractions and less contaminated by metals than the stabilised C 3 SOM of the clay fraction, is more easily degraded by microorganisms. - Measure of δ 13 C and total metal concentrations in size fractions of contaminated soils suggests an influence of metals on the soil organic matter dynamic

  7. Criopreservação e embriogênese somática de calos de Dimocarpus longan Cryopreservation and somatic embryogenesis of Dimocarpus longan calli

    Directory of Open Access Journals (Sweden)

    Kazumitsu Matsumoto

    2004-12-01

    Full Text Available Os objetivos deste trabalho foram avaliar os efeitos de crioprotetores na criopreservação e da sacarose na embriogênise somática de calos de Dimocarpus longan. Após degelo os calos foram cultivados em meio de multiplicação, e a massa da matéria fresca foi determinada. Para se obter os embriões somáticos, calos e massas pro-embriônicas foram transferidos para meio de cultura contendo diferentes concentrações de sacarose. Entre os crioprotetores, a mistura de 5% de glicerol + 5% de dimetilsulfóxido proporcionou a maior quantidade de massa fresca dos calos. O maior número de embriões foi obtido no meio de cultura com 50 g L-1 de sacarose. Os resultados mostram que calos de Dimocarpus longan podem ser criopreservados e plântulas podem ser obtidas.Cryoprotectors on cryopreservation and sucrose on somatic embryogenesis of Dimocarpus longan calli were evaluated. The post-thaw calli were cultivated on multiplication medium, and the obtained fresh matter mass was measured. In order to obtain somatic embryos, calli and pro-embryonic masses were transferred into culture medium containing different concentrations of sucrose. Among the cryoprotectors, the mixture of 5% glycerol + 5% dimethylsulfoxide provided the largest quantity of calli fresh matter. The highest number of embryos was obtained on the culture medium with 50 g L-1 sucrose. The results show that Dimocarpus longan calli can be cryopreserved and plantlets be obtained.

  8. 1968 Listing of Swimming Pool Equipment.

    Science.gov (United States)

    National Sanitation Foundation, Ann Arbor, MI. Testing Lab.

    An up-to-date listing of swimming pool equipment including--(1) companies authorized to display the National Sanitation Foundation seal of approval, (2) equipment listed as meeting NSF swimming pool equipment standards relating to diatomite type filters, (3) equipment listed as meeting NSF swimming pool equipment standard relating to sand type…

  9. Solid Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    Supported by a generous quantity of full-color illustrations and interesting sidebars, Solid Matter introduces the basic characteristics and properties of solid matter. It briefly describes the cosmic connection of the elements, leading readers through several key events in human pre-history that resulted in more advanced uses of matter in the solid state. Chapters include:. -Solid Matter: An Initial Perspective. -Physical Behavior of Matter. -The Gravity of Matter. -Fundamentals of Materials Science. -Rocks and Minerals. -Metals. -Building Materials. -Carbon Earth's Most Versatile Element. -S

  10. Clinical blood pool MR Imaging

    Energy Technology Data Exchange (ETDEWEB)

    Leiner, Tim [Maastrich University Medical Center (Netherlands). Dept. of Radiology; Goyen, Martin [University Medical Center Hamburg-Eppendorf (Germany); Rohrer, Mathias [Bayer Schering Pharma AG, Berlin (Germany). European Business Unit Diagnostic Imaging; Schoenberg, Stefan O. (eds.) [University Hospital Mannheim Medical Faculty Mannheim - Heidelberg Univ. (Germany). Dept. of Clinical Radiology and Nuclear Medicine

    2008-07-01

    Clinical Blood Pool MR Imaging - This excellent treatise on Vasovist {sup registered} created by a team of exceptional faculty who are pioneers in MR Angiography covers the basic techniques, safety, efficacy, image processing and pharmaco-economic details to successfully implement a new level of MRA image quality with this new contrast agent. Martin Prince, Cornell University, New York The editors and authors have made groundbreaking contributions towards establishing MR angiography in various investigative settings, rendering it more precise and applying it for diverse indications. The work presented here is founded upon the extensive experience of the editors, as well as the broad range of experience from other scientific working groups. Maximilian Reiser, Ludwig Maximilian University, Munich Vasovist {sup registered} (Gadofosveset), worldwide the first blood pool agent, has only recently become available for clinical use, but has already gained wide acceptance as a tool to improve magnetic resonance angiography. This book presents the first in-depth introduction to the basic physicochemical aspects of the agent, the application of Vasovist {sup registered} in clinical MRA, as well as potential clinical applications beyond MRA and patient management-related aspects. The first part of the book explains basic and technical properties of the agent and the differences of Vasovist {sup registered} compared to currently available extracellular agents. The second part contains detailed chapters on safety and efficacy. In the third part the focus is on MR angiographic applications, and in the fourth part of the book potential clinical fields beyond MRA are explored. All clinical chapters feature ready-to-use clinical protocols and a series of take home messages that concisely summarize the current role of blood pool imaging for each specific indication. (orig.)

  11. New Approaches in Soil Organic Matter Fluorescence; A Solid Phase Fluorescence Approach

    Science.gov (United States)

    Bowman, M. M.; Sanclements, M.; McKnight, D. M.

    2017-12-01

    Fluorescence spectroscopy is a well-established technique to investigate the composition of organic matter in aquatic systems and is increasingly applied to soil organic matter (SOM). Current methods require that SOM be extracted into a liquid prior to analysis by fluorescence spectroscopy. Soil extractions introduce an additional layer of complexity as the composition of the organic matter dissolved into solution varies based upon the selected extractant. Water is one of the most commonly used extractant, but only extracts the water-soluble fraction of the SOM with the insoluble soil organic matter fluorescence remaining in the soil matrix. We propose the use of solid phase fluorescence on whole soils as a potential tool to look at the composition of organic matter without the extraction bias and gain a more complete understand of the potential for fluorescence as a tool in terrestrial studies. To date, the limited applications of solid phase fluorescence have ranged from food and agriculture to pharmaceutical with no clearly defined methods and limitations available. We are aware of no other studies that use solid phase fluorescence and thus no clear methods to look at SOM across a diverse set of soil types and ecosystems. With this new approach to fluorescence spectroscopy there are new challenges, such as blank correction, inner filter effect corrections, and sample preparation. This work outlines a novel method for analyzing soil organic matter using solid phase fluorescence across a wide range of soils collected from the National Ecological Observatory Network (NEON) eco-domains. This method has shown that organic matter content in soils must be diluted to 2% to reduce backscattering and oversaturation of the detector in forested soils. In mineral horizons (A) there is observed quenching of the humic-like organic matter, which is likely a result of organo-mineral complexation. Finally, we present preliminary comparisons between solid and liquid phase

  12. [SOMS-2: translation into portuguese of the screening for Somatoform Disorders].

    Science.gov (United States)

    Fabião, Cristina; Costa E Silva, Carolina; Fleming, Manuela; Barbosa, António

    2008-01-01

    The diagnosis of Somatization Disorder (SD) requires the presence of somatic medically unexplained symptoms (MUS) which must be assessed so that organic diseases may be excluded. SOMS-2 is a self-report measure for SD that assesses medically unexplained symptoms by requiring participants to answer affirmatively and qualify any of the complaints as MUS, only if they have obtained from his doctor the opinion that the said complaint is not due to an organic disease. According to the authors, original SOMS-2 has a good internal consistency with Cronbach's a = .87 and a good correlation between selfratings and interview (r = .75). After obtaining the author's permission, translation from and into English has been made by experienced translators. The resulting questionnaire has been used on a small group of patients. Afterwards the items in which there were difficulties in understanding during the pretest were identified and experienced practitioners were asked for suggestions. The resulting version was answered by 123 primary health care patients (sample I). After some modifications of the SOMS-2, another group of 190 primary health care patients answered the questionnaire (sample II). Most patients, in the first sample, found it difficult to understand that, in order to answer affirmatively it was necessary to answer three questions: 1) is the symptom present? 2) has your doctor found no clear causes for the symptom? 3) does the symptom affect your well-being? The difficulties in understanding items 21 and 45 (pre-test) were confirmed. Items 11, 28 and 38 were more easily understood when worded differently. In sample I, less than 5% of positive answers were given to items 20, 21, 23, 40, 43, 45, and 51. Probably because of the low education level of the Portuguese population which this sample reflects, difficulties in carrying out the instructions given at the beginning made it advisable to modify the SOMS-2, so that the three implicit questions in each question of the

  13. Microbial N and P mining regulates the effect of N deposition on soil organic matter turnover

    Science.gov (United States)

    Meyer, Nele; Welp, Gerhard; Rodionov, Andrei; Borchard, Nils; Martius, Christopher; Amelung, Wulf

    2017-04-01

    Nitrogen (N) deposition to soils has become a global issue during the last decades. Its effect on mineralization of soil organic carbon (SOC), however, is still debated. Common theories based on Liebig's law predict higher SOC mineralization rates in nutrient-rich than in nutrient-poor soils. Contrastingly, the concept of microbial N mining predicts lower mineralization rates after N deposition. The latter is explained by ceased decomposition of recalcitrant soil organic matter (SOM) as the need of microbes to acquire N from this pool decreases. As N deposition might shift the nutrient balance towards relative phosphorus (P) deficiency, it is also necessary to consider P mining in this context. Due to limited knowledge about microbial nutrient mining, any predictions of N deposition effects are difficult. This study aims at elucidating the preconditions under which microbial nutrient mining occurs in soil. We hypothesized that the occurrence of N and P mining is controlled by the current nutrient status of the soil. Likewise, soils might respond differently to N additions. To investigate this hypothesis, we conducted substrate-induced respiration measurements on soils with pronounced gradients of N and P availability. We used topsoil samples taken repeatedly from a site which was up to 7 years under bare fallow (Selhausen, Germany) and up to 4 m deep tropical forest soils (Kalimantan, Indonesia). Additional nutrient manipulations (glucose, glucose+N, glucose+P, glucose+N+P additions) were conducted to study the effect of nutrient additions. Samples were incubated for one month. We further conducted 13C labeling experiments to trace the sources of CO2 (sugar vs. SOM derived CO2) for further hints on nutrient mining. Mineralization of glucose was limited by a lack of available N in the bare fallow soil but microbes were able to slowly acquire N from previously unavailable pools. This resulted in a slightly higher release of native SOM-derived CO2 compared to N

  14. Speech Matters

    DEFF Research Database (Denmark)

    Hasse Jørgensen, Stina

    2011-01-01

    About Speech Matters - Katarina Gregos, the Greek curator's exhibition at the Danish Pavillion, the Venice Biannual 2011.......About Speech Matters - Katarina Gregos, the Greek curator's exhibition at the Danish Pavillion, the Venice Biannual 2011....

  15. Memory Matters

    Science.gov (United States)

    ... Staying Safe Videos for Educators Search English Español Memory Matters KidsHealth / For Kids / Memory Matters What's in ... of your complex and multitalented brain. What Is Memory? When an event happens, when you learn something, ...

  16. Method of measuring a liquid pool volume

    Science.gov (United States)

    Garcia, G.V.; Carlson, N.M.; Donaldson, A.D.

    1991-03-19

    A method of measuring a molten metal liquid pool volume and in particular molten titanium liquid pools is disclosed, including the steps of (a) generating an ultrasonic wave at the surface of the molten metal liquid pool, (b) shining a light on the surface of a molten metal liquid pool, (c) detecting a change in the frequency of light, (d) detecting an ultrasonic wave echo at the surface of the molten metal liquid pool, and (e) computing the volume of the molten metal liquid. 3 figures.

  17. Bysykler : perspektiver på bysykkelordninger som en del av en bærekraftig bytransport og urban identitet

    OpenAIRE

    Langfeldt, Tuva

    2011-01-01

    SAMMENDRAG - Byutviklingen er de senere årene preget av grønne visjoner og planlegging for levende og bærekraftige byer. Et viktig ledd i denne utviklingen er menneskelig bevegelse og mobilitet, og det ses flere og flere steder med nye øyne på hvordan mobiliteten i byen kan og bør være. Fokus på sykkel som framkomstmiddel har blitt stadig mer populært, i Europa som USA, og som et resultat av behov for en mer syklende og mindre bilkjørende befolkning er det dukket opp bysykkelordninger i bå...

  18. The Microbial Efficiency-Matrix Stabilization (MEMS) framework integrates plant litter decomposition with soil organic matter stabilization: do labile plant inputs form stable soil organic matter?

    Science.gov (United States)

    Cotrufo, M Francesca; Wallenstein, Matthew D; Boot, Claudia M; Denef, Karolien; Paul, Eldor

    2013-04-01

    The decomposition and transformation of above- and below-ground plant detritus (litter) is the main process by which soil organic matter (SOM) is formed. Yet, research on litter decay and SOM formation has been largely uncoupled, failing to provide an effective nexus between these two fundamental processes for carbon (C) and nitrogen (N) cycling and storage. We present the current understanding of the importance of microbial substrate use efficiency and C and N allocation in controlling the proportion of plant-derived C and N that is incorporated into SOM, and of soil matrix interactions in controlling SOM stabilization. We synthesize this understanding into the Microbial Efficiency-Matrix Stabilization (MEMS) framework. This framework leads to the hypothesis that labile plant constituents are the dominant source of microbial products, relative to input rates, because they are utilized more efficiently by microbes. These microbial products of decomposition would thus become the main precursors of stable SOM by promoting aggregation and through strong chemical bonding to the mineral soil matrix. © 2012 Blackwell Publishing Ltd.

  19. Modeling the vertical soil organic matter profile using Bayesian parameter estimation

    Directory of Open Access Journals (Sweden)

    M. C. Braakhekke

    2013-01-01

    Full Text Available The vertical distribution of soil organic matter (SOM in the profile may constitute an important factor for soil carbon cycling. However, the formation of the SOM profile is currently poorly understood due to equifinality, caused by the entanglement of several processes: input from roots, mixing due to bioturbation, and organic matter leaching. In this study we quantified the contribution of these three processes using Bayesian parameter estimation for the mechanistic SOM profile model SOMPROF. Based on organic carbon measurements, 13 parameters related to decomposition and transport of organic matter were estimated for two temperate forest soils: an Arenosol with a mor humus form (Loobos, the Netherlands, and a Cambisol with mull-type humus (Hainich, Germany. Furthermore, the use of the radioisotope 210Pbex as tracer for vertical SOM transport was studied. For Loobos, the calibration results demonstrate the importance of organic matter transport with the liquid phase for shaping the vertical SOM profile, while the effects of bioturbation are generally negligible. These results are in good agreement with expectations given in situ conditions. For Hainich, the calibration offered three distinct explanations for the observations (three modes in the posterior distribution. With the addition of 210Pbex data and prior knowledge, as well as additional information about in situ conditions, we were able to identify the most likely explanation, which indicated that root litter input is a dominant process for the SOM profile. For both sites the organic matter appears to comprise mainly adsorbed but potentially leachable material, pointing to the importance of organo-mineral interactions. Furthermore, organic matter in the mineral soil appears to be mainly derived from root litter, supporting previous studies that highlighted the importance of root input for soil carbon sequestration. The 210

  20. Large-scale pool fires

    Directory of Open Access Journals (Sweden)

    Steinhaus Thomas

    2007-01-01

    Full Text Available A review of research into the burning behavior of large pool fires and fuel spill fires is presented. The features which distinguish such fires from smaller pool fires are mainly associated with the fire dynamics at low source Froude numbers and the radiative interaction with the fire source. In hydrocarbon fires, higher soot levels at increased diameters result in radiation blockage effects around the perimeter of large fire plumes; this yields lower emissive powers and a drastic reduction in the radiative loss fraction; whilst there are simplifying factors with these phenomena, arising from the fact that soot yield can saturate, there are other complications deriving from the intermittency of the behavior, with luminous regions of efficient combustion appearing randomly in the outer surface of the fire according the turbulent fluctuations in the fire plume. Knowledge of the fluid flow instabilities, which lead to the formation of large eddies, is also key to understanding the behavior of large-scale fires. Here modeling tools can be effectively exploited in order to investigate the fluid flow phenomena, including RANS- and LES-based computational fluid dynamics codes. The latter are well-suited to representation of the turbulent motions, but a number of challenges remain with their practical application. Massively-parallel computational resources are likely to be necessary in order to be able to adequately address the complex coupled phenomena to the level of detail that is necessary.

  1. Storage and turnover of organic matter in soil

    Energy Technology Data Exchange (ETDEWEB)

    Torn, M.S.; Swanston, C.W.; Castanha, C.; Trumbore, S.E.

    2008-07-15

    Historically, attention on soil organic matter (SOM) has focused on the central role that it plays in ecosystem fertility and soil properties, but in the past two decades the role of soil organic carbon in moderating atmospheric CO{sub 2} concentrations has emerged as a critical research area. This chapter will focus on the storage and turnover of natural organic matter in soil (SOM), in the context of the global carbon cycle. Organic matter in soils is the largest carbon reservoir in rapid exchange with atmospheric CO{sub 2}, and is thus important as a potential source and sink of greenhouse gases over time scales of human concern (Fischlin and Gyalistras 1997). SOM is also an important human resource under active management in agricultural and range lands worldwide. Questions driving present research on the soil C cycle include: Are soils now acting as a net source or sink of carbon to the atmosphere? What role will soils play as a natural modulator or amplifier of climatic warming? How is C stabilized and sequestered, and what are effective management techniques to foster these processes? Answering these questions will require a mechanistic understanding of how and where C is stored in soils. The quantity and composition of organic matter in soil reflect the long-term balance between plant carbon inputs and microbial decomposition, as well as other loss processes such as fire, erosion, and leaching. The processes driving soil carbon storage and turnover are complex and involve influences at molecular to global scales. Moreover, the relative importance of these processes varies according to the temporal and spatial scales being considered; a process that is important at the regional scale may not be critical at the pedon scale. At the regional scale, SOM cycling is influenced by factors such as climate and parent material, which affect plant productivity and soil development. More locally, factors such as plant tissue quality and soil mineralogy affect

  2. Dark Matter

    Indian Academy of Sciences (India)

    What You See Ain't What. You Got, Resonance, Vol.4,. No.9,1999. Dark Matter. 2. Dark Matter in the Universe. Bikram Phookun and Biman Nath. In Part 11 of this article we learnt that there are compelling evidences from dynamics of spiral galaxies, like our own, that there must be non-luminous matter in them. In this.

  3. Structural integrity assessment of HANARO pool cover

    International Nuclear Information System (INIS)

    Ryu, Jeong Soo

    2001-11-01

    This report is for the seismic analysis and the structural integrity evaluation of HANARO Pool Cover in accordances with the requirement of the Technical Specification for Seismic Analysis of HANARO Pool Cover. For performing the seismic analysis and evaluating the structural integrity for HANARO Pool Cover, the finite element analysis model using ANSYS 5.7 was developed and the dynamic characteristics were analyzed. The seismic response spectrum analyses of HANARO Pool Cover under the design floor response spectrum loads of OBE and SSE were performed. The analysis results show that the stress values in HANARO Pool Cover for the seismic loads are within the ASME Code limits. It is also confirmed that the fatigue usage factor is less than 1.0. Therefore any damage on structural integrity is not expected when an HANARO Pool Cover is installed in the upper part of the reactor pool

  4. Faktorer som förklarar miljövänligt beteende hos unga vuxna

    OpenAIRE

    Rikner, Amanda

    2009-01-01

    Människors miljörelaterade beteenden behöver förbättras. I studien undersöktes unga vuxna universitetsstuderandes syn på klimatproblematiken. En enkät delades ut som mätte miljövänligt beteende, ansvarskänsla, tillit till forskning, upplevelse av att kunna påverka och kunskap när det gäller klimatproblematiken. Deltagarna fick också beskriva anledningar som möjliggör eller förhindrar en förbättring av klimatproblematiken. Deltog gjorde 97 personer. Resultatet visade på signifikanta samband me...

  5. Tidlige brukere av alkohol – hvem er de? Kjennetegn ved ungdom som starter tidlig med alkohol

    Directory of Open Access Journals (Sweden)

    Anders Grimsmo

    2009-10-01

    Full Text Available  SAMMENDRAGDebutalder med alkoholrus er en sterk prediktor for senere alkoholbruk. I denne undersøkelsen har visammenliknet de som starter med alkohol tidlig og før det er kulturelt akseptert, med ungdommenesom begynner i konfirmasjonsalder og de som utsetter alkoholdebuten. Vi finner at gruppen sombegynner tidlig ikke bare bryter de lokale tradisjonene for alkoholkonsum, men er i opposisjon tilnormer og autoriteter generelt. Alkohol er et positivt symbol for gruppen og det å ruse seg et ritualesom gir mening i deres miljø. Hjemmet står i den sterkeste posisjonen til å kunne utsette ungdommensalkoholdebut. Vi skisserer hvilke implikasjoner dette bør ha for strategien i det forebyggende arbeidet.

  6. Faktorer som påverkar barndödligheten i Etiopien

    OpenAIRE

    Östman, Hanna

    2014-01-01

    Temat för detta examensarbete är barndödlighet i Etiopien. Syftet är att undersöka den höga småbarnsdödligheten, orsakad av diarré och malaria. Detta är ett beställningsarbete för organisationen PADet, som har ett samarbete med yrkeshögskolan Arcada. Med småbarn menas i denna studie, barn under fem år. Frågeställningarna för arbetet är, Vilka är de främsta orsakerna som påverkar småbarnsdödligheten vid diarré och malaria? Och Vad görs idag för att minska på småbarnsdödligheten vid diarré och ...

  7. BIM som Informationsbärare in i Förvaltningen : En studie vid Forsmarks Kraftgrupp

    OpenAIRE

    Svens, Therése

    2013-01-01

    BIM, Building Information Modeling, börjar vinna mark inom byggbranschen i Sverige och är en vedertagen process i vart och vartannat byggprojekt. Forsmarks Kraftgrupp står inför både upprustningar av sina anläggningar och nyproduktion av bland annat kontor, verkstad och hotell. BIM framstår nu som en lukrativ metod för att dra ner på projektkostnaderna, men även för att få ytterligare ordning och struktur på den enorma mängd dokumentation som ackumulerat under de dryga trettio åren av drift. ...

  8. Adversary phase change detection using S.O.M. and text data

    International Nuclear Information System (INIS)

    Speed, Ann Elizabeth; Doser, Adele Beatrice; Warrender, Christina E.

    2010-01-01

    In this work, we developed a self-organizing map (SOM) technique for using web-based text analysis to forecast when a group is undergoing a phase change. By 'phase change', we mean that an organization has fundamentally shifted attitudes or behaviors. For instance, when ice melts into water, the characteristics of the substance change. A formerly peaceful group may suddenly adopt violence, or a violent organization may unexpectedly agree to a ceasefire. SOM techniques were used to analyze text obtained from organization postings on the world-wide web. Results suggest it may be possible to forecast phase changes, and determine if an example of writing can be attributed to a group of interest.

  9. Forskeres arbejde med oplevelser af børns tegninger som forskningsmetode

    DEFF Research Database (Denmark)

    Nielsen, Anne Maj

    2012-01-01

    , experiences, intentions and engagement that may be difficult to articulate verbally. Research can include children’s art and drawings to study phenomena such as children’s feelings, emotions, experiences, intentions and engagements. Transparency of the ways in which art and drawings in specific ways...... at gøre rede for hvordan forskerens sanselige og æstetiske oplevelser af børns tegninger kan gøres transparente ved at tegninger betragtes som ’æstetiske objekter’ som led i forskningsprocessen. In art and drawing children can visually express phenomena in their mind such as feelings, emotions...... contribute to knowledge is a challenge in research. The aim of this article is to describe and discuss how the construct ‘aesthetic object’ may offer researchers an approach to children’s art and drawings that can explicitly include the researcher’s sensory and aesthetic experiences as knowledge....

  10. Faults detection approach using PCA and SOM algorithm in PMSG-WT system

    Directory of Open Access Journals (Sweden)

    Mohamed Lamine FADDA

    2016-07-01

    Full Text Available In this paper, a new approach for faults detection in observable data system wind turbine - permanent magnet synchronous generator (WT-PMSG, the studying objective, illustrate the combination (SOM-PCA to build Multi-local-PCA models faults detection in system (WT-PMSG, the performance of the method suggested to faults detection in system data, finding good results in simulation experiment.

  11. Sorg som relation og emotion – konturerne af en kritik af den tiltagende patologisering af sorgen

    DEFF Research Database (Denmark)

    Jacobsen, Michael Hviid

    2017-01-01

    Vi oplever i disse år en stadig større interesse for sorgen som genstandsfelt for forskellige forskningsmæssige initiativer og satsninger samt en stadig mere intensiveret kamp for de ressourcer, der følger med denne udvikling. Selvom vi altid skal byde ny viden velkommen, så bør vi også være vars...

  12. Sundhed som tema på den pædagogiske dagsorden

    DEFF Research Database (Denmark)

    Pedersen, Ulla; Schulz, Anette

    2015-01-01

    Dagtilbud og skole fremhæves i de nationale mål for danskernes sundhed som vigtige indsatsmiljøer (Regeringen, 2014). I dette kapitel berøres indledningsvist dagtilbuddets og skolens sundhedsfremmende rolle. Herefter præsenteres en række cases, hvor to faktorer har været særligt afgørende for at ...

  13. Aktionslæring som metode til udvikling af inkluderende praksis

    DEFF Research Database (Denmark)

    Olsson, Janne; Maltzahn, Lene Nyboe

    2014-01-01

    Kapitlet handler om, hvordan genkendelige hverdagspraksisser i daginstitutioner i nogle tilfælde ekskluderer børn, mens andre praksisser understøtter, at børn kan tage del i fællesskaber. Med afsæt i en konkret case argumenteres der for, at aktionslæring som metode kan gøre det muligt for pædagog...

  14. Data splitting for artificial neural networks using SOM-based stratified sampling.

    Science.gov (United States)

    May, R J; Maier, H R; Dandy, G C

    2010-03-01

    Data splitting is an important consideration during artificial neural network (ANN) development where hold-out cross-validation is commonly employed to ensure generalization. Even for a moderate sample size, the sampling methodology used for data splitting can have a significant effect on the quality of the subsets used for training, testing and validating an ANN. Poor data splitting can result in inaccurate and highly variable model performance; however, the choice of sampling methodology is rarely given due consideration by ANN modellers. Increased confidence in the sampling is of paramount importance, since the hold-out sampling is generally performed only once during ANN development. This paper considers the variability in the quality of subsets that are obtained using different data splitting approaches. A novel approach to stratified sampling, based on Neyman sampling of the self-organizing map (SOM), is developed, with several guidelines identified for setting the SOM size and sample allocation in order to minimize the bias and variance in the datasets. Using an example ANN function approximation task, the SOM-based approach is evaluated in comparison to random sampling, DUPLEX, systematic stratified sampling, and trial-and-error sampling to minimize the statistical differences between data sets. Of these approaches, DUPLEX is found to provide benchmark performance with good model performance, with no variability. The results show that the SOM-based approach also reliably generates high-quality samples and can therefore be used with greater confidence than other approaches, especially in the case of non-uniform datasets, with the benefit of scalability to perform data splitting on large datasets. Copyright 2009 Elsevier Ltd. All rights reserved.

  15. Legalisering som lösning? Erfarenheter av holländsk eutanasipraxis

    NARCIS (Netherlands)

    Boer, Th.A.

    2002-01-01

    Fastän vi lever i ett Europa som växer samman, så fortsätter dock många gränser att bestå. Vissa skillnader förblir eller har i de förgångna årtiondena till och med blivit djupare. Dödshjälpsdebatterna i Holland och Skandinavien ger oss ett exempel. Två stater med till stor del lika kultur, men

  16. Bærme (DDGS) som proteinfoder til malkekøer

    DEFF Research Database (Denmark)

    Sehested, Jakob; Sørensen, Martin Tang; Weisbjerg, Martin Riis

    2015-01-01

    DDGS er et proteinrigt fodermiddel fra produktionen af bio-etanol baseret på korn og majs, og det forventes på markedet i stigende mængder. Kornbaseret DDGS kan være et godt proteinfoder som uden negativ effekt på mælkeproduktion eller -kvalitet kan indgå med 15 % af rationens tørstof og kan...

  17. Som i et spejl - Hans Egede-receptionen gennem tre hundrede år

    DEFF Research Database (Denmark)

    Kjærgaard, Kathrine

    2008-01-01

    stor, og længe ville man ikke vide af Hans Egede, der - skønt født i Norge - opfattedes som dansk. Først efter 1945, hvor Norge i kølvandet på Danskehjælpen under Anden Verdenskrig omsider forsonede sig med Danmark, tog man atter Hans Egede til sig. Blandt større mindesmærker, som er blevet til siden...... 1945, kan nævnes Nicolai Schiølls ungdommelige statue af grønlandsmissionæren i det centrale Oslo (1965) og Axel Revolds monumentale udskmykning af kirken i Hans Egedes nordnorske fødeby Harstad (1958). I Danmark, hvor sorgen over tabet af Norge var stor, var man i årene efter 1814 meget...... tilbageholdende med at omklamre tidligere norske landsmænd som Hans Egede. Først hen mod slutningen af 1800-tallet begyndte forbeholdene at smelte et efter et. Den definitive omdefinering af den dansk-norske 1700-tals patriot til national dansk kirkefyrste kom med opstillingen 1913 af hans statue ved Marmorkirken...

  18. Reklamen som pastiche. Om Dansk Sygeplejeråds annoncekampagne efteråret 1986

    Directory of Open Access Journals (Sweden)

    Gunhild Agger

    1989-08-01

    Full Text Available Der er flere og flere medieproducenter, der anser modtagerne for at besidde en vis tekstuel intelligens. Fra detektivpasticher som Dick Spanner og Batman over den konstant genreparodierende "Moon- lighting" (De heldige helte til Poul og Nulles respektløse faktion "I sandhedens Tjeneste" leges der med betydningsdannelsen. Seerne/læserne indbydes til selv at spille ping-pong med billeder og tekst. Gunhild Agger analyserer her denne tendens, sådan som den kom- mer til udtryk inden for reklamen: Anker Jørgensen som James Bond, og kondomer til Prinsessen på Ærten! Mest indgående beskæftiger hun sig med Dansk Sygeplejeråds brug af myten om sygeplejersken i en annoncekampagne op mod overenskomstforhandlingerne i 1987. Gunhild Agger nøjes ikke med en indholdsanalyse af annoncerne, men beskriver hele kampagnen: Dansk Sygeplejeråds hensigter med frem- stødet, kampagnens lancering over for den tre-dobbelte målgruppe, læsernes formodede reception, og kampagnens politiske og holdnings- mæssige effekter.

  19. Djævelen som Guds advokat - Nietzsche, filosofien og Paulus

    DEFF Research Database (Denmark)

    Pallesen, Carsten

    2012-01-01

    Artiklen tegner et dobbeltportræt af Paulus og Nietzsche ud fra en række nyere diskussioner om Nietzsches syn på Paulus hos aktuelle Nietzscheforskere, men også med udblik til den Paulus-renæssance, som har fundet sted i filosofien. Med det sidste tænkes navnlig på den franske filosof Alain Badious...... tese om Paulus som universalismens tænker. Artiklen fremhæver, hvordan hermeneutiske, kommunikationsteoretiske og semiotiske tilgange i den nyere tyske forskning navnlig hos Werner Stegmaier har ændret synet på forholdet mellem Nietzsches ’tegn’ (Dionysos, Zarathustra, ’anti-krist’) over for Nietzsches...... retfærdiggørelse ved troen. Nietzsches forhold til kristendommen er ikke kun bestemt af negative vurderinger, men tillige af en ambivalent taknemmelighed, som når han i den sene fase af forfatterskabet på en gang identificerer sig med Dionysos og ’den korsfæstede’....

  20. Lyd som kommunikation. En tværfaglig forskningsoversigt og en dagsorden for medieforskningen

    Directory of Open Access Journals (Sweden)

    Klaus Bruhn Jensen

    2008-06-01

    Full Text Available Lyden har ikke noget videnskabeligt hjem – i modsætning til f.eks. faste og levende billeder, der traditionelt er blevet studeret af henholdsvis kunsthistorien og filmvidenskaben. Denne artikel giver en oversigt over de mange, meget forskellige slags forskning om lyd. Formålet er at stimulere og kvalificere mere medieforskning om lyd. Hovedvægten ligger på lyd som kommunikation i og omkring medierne – som en kilde til mening og en ressource i social og kulturel handling, snarere end på lyd i et teknisk eller akustisk perspektiv (se f.eks. Plomp, 2002. Første del af artiklen gennemgår forskellige humanistiske og samfundsvidenskabelige tilgange til lydens tre grundformer – tale, musik og soundscapes eller lydmiljøer. Det midterste afsnit diskuterer den tidligere forsknings relevans for forskellige slags medier; artiklen skelner her mellem tre grader af medier. Og artiklens sidste del samler de tværfaglige indsigter i en dagsorden for (meget mere medieforskning om lyd som kommunikation.

  1. Lyd som kommunikation. En tværfaglig forskningsoversigt og en dagsorden for medieforskningen

    Directory of Open Access Journals (Sweden)

    Klaus Bruhn Jensen

    2006-06-01

    Full Text Available Lyden har ikke noget videnskabeligt hjem – i modsætning til f.eks. faste og levende billeder, der traditionelt er blevet studeret af henholdsvis kunsthistorien og filmvidenskaben. Denne artikel giver en oversigt over de mange, meget forskellige slags forskning om lyd. Formålet er at stimulere og kvalificere mere medieforskning om lyd. Hovedvægten ligger på lyd som kommunikation i og omkring medierne – som en kilde til mening og en ressource i social og kulturel handling, snarere end på lyd i et teknisk eller akustisk perspektiv (se f.eks. Plomp, 2002. Første del af artiklen gennemgår forskellige humanistiske og samfundsvidenskabelige tilgange til lydens tre grundformer – tale, musik og soundscapes eller lydmiljøer. Det midterste afsnit diskuterer den tidligere forsknings relevans for forskellige slags medier; artiklen skelner her mellem tre grader af medier. Og artiklens sidste del samler de tværfaglige indsigter i en dagsorden for (meget mere medieforskning om lyd som kommunikation.

  2. Distinct roles of SOM and VIP interneurons during cortical Up states

    Directory of Open Access Journals (Sweden)

    Garrett T. Neske

    2016-07-01

    Full Text Available During cortical network activity, recurrent synaptic excitation among pyramidal neurons is approximately balanced by synaptic inhibition, which is provided by a vast diversity of inhibitory interneurons. The relative contributions of different interneuron subtypes to inhibitory tone during cortical network activity is not well understood. We previously showed that many of the major interneuron subtypes in mouse barrel cortex are highly active during Up states (Neske et al., 2015; while fast-spiking (FS, parvalbumin (PV-positive cells were the most active interneuron subtype, many non-fast-spiking (NFS, PV-negative interneurons were as active or more active than neighboring pyramidal cells. This suggests that the NFS cells could play a role in maintaining or modulating Up states. Here, using optogenetic techniques, we further dissected the functional roles during Up states of two major NFS, PV-negative interneuron subtypes: somatostatin (SOM-positive cells and vasoactive intestinal peptide (VIP-positive cells. We found that while pyramidal cell excitability during Up states significantly increased when SOM cells were optogenetically silenced, VIP cells did not influence pyramidal cell excitability either upon optogenetic silencing or activation. VIP cells failed to contribute to Up states despite their ability to inhibit SOM cells strongly. We suggest that the contribution of VIP cells to the excitability of pyramidal cells may vary with cortical state.

  3. Feature combination analysis in smart grid based using SOM for Sudan national grid

    Science.gov (United States)

    Bohari, Z. H.; Yusof, M. A. M.; Jali, M. H.; Sulaima, M. F.; Nasir, M. N. M.

    2015-12-01

    In the investigation of power grid security, the cascading failure in multicontingency situations has been a test because of its topological unpredictability and computational expense. Both system investigations and burden positioning routines have their limits. In this project, in view of sorting toward Self Organizing Maps (SOM), incorporated methodology consolidating spatial feature (distance)-based grouping with electrical attributes (load) to evaluate the vulnerability and cascading impact of various part sets in the force lattice. Utilizing the grouping result from SOM, sets of overwhelming stacked beginning victimized people to perform assault conspires and asses the consequent falling impact of their failures, and this SOM-based approach viably distinguishes the more powerless sets of substations than those from the conventional burden positioning and other bunching strategies. The robustness of power grids is a central topic in the design of the so called "smart grid". In this paper, to analyze the measures of importance of the nodes in a power grid under cascading failure. With these efforts, we can distinguish the most vulnerable nodes and protect them, improving the safety of the power grid. Also we can measure if a structure is proper for power grids.

  4. Livermore pool-type reactor

    International Nuclear Information System (INIS)

    Mann, L.G.

    1977-01-01

    The Livermore Pool-Type Reactor (LPTR) has served a dual purpose since 1958--as an instrument for fundamental research and as a tool for measurement and calibration. Our early efforts centered on neutron-diffraction, fission, and capture gamma-ray studies. During the 1960's it was used for extensive calibration work associated with radiochemical and physical measurements on nuclear-explosive tests. Since 1970 the principal applications have been for trace-element measurements and radiation-damage studies. Today's research program is dominated by radiochemical studies of the shorter-lived fission products and by research on the mechanisms of radiation damage. Trace-element measurement for the National Uranium Resource Evaluation (NURE) program is the major measurement application today

  5. Cardiac blood pool emission tomography

    International Nuclear Information System (INIS)

    Itti, R.; Philippe, L.; Lorgeron, J.M.; Charbonnier, B.; Raynaud, P.; Brochier, M.

    1983-01-01

    After blood pool labeling using technetium-99m, a series of cardiac pictures is acquired during the rotation of a gamma-camera about the patient. Computer processing leads to reconstruction of various tomographic slices from the original planar projection. Electrocardiographic gating selects the different phases of the cardiac cycle. Individual slices through the left ventricular region are added in order to provide ''thick'' slices on which global and regional parameters of the left ventricular function can be determined. Due to the proportionality existing between count rates and labeled blood volumes, any geometrical model can be avoided. The delineation of regions of interest for count integration is made easier due to the absence of superimposition of structures; no correction for background is necessary. Tomography thus appears to be more consistent and more accurate than the classical methods using planar projections. In addition, right ventricular morphological and kinetic studies can be performed in the same conditions as for the left ventricle [fr

  6. Arc-weld pool interactions

    International Nuclear Information System (INIS)

    Glickstein, S.S.

    1978-08-01

    The mechanisms involved in arc-weld pool interactions are extremely complex and no complete theory is presently available to describe much of the phenomena observed during welding. For the past several years, experimental and analytical studies have been undertaken at the Bettis Atomic Power Laboratory to increase basic understanding of the gas tungsten arc welding process. These studies have included experimental spectral analysis of the arc in order to determine arc temperature and analytical modeling of the arc and weld puddle. The investigations have been directed toward determining the cause and effects of variations in the energy distribution incident upon the weldment. In addition, the effect of weld puddle distortion on weld penetration was investigated, and experimental and analytical studies of weld process variables have been undertaken to determine the effects of the variables upon weld penetration and configuration. A review of the results and analysis of these studies are presented

  7. Stabilization of organic matter in soils: role of amorphous mineral phases

    Science.gov (United States)

    Zewde Tamrat, Wuhib; Rose, Jérôme; Levard, Clément; Chaurand, Perrine; Basile-Doelsch, Isabelle

    2016-04-01

    Soil organic matter (SOM) globally contributes the largest portion of continental carbon stock. One major issue concerning this large C pool includes its instability by mineralization and erosion due to land use. The main hypothesis of this work is that physicochemical stabilization of SOM is mainly driven by interactions of organic compounds, not with mineral surfaces as classically considered, but with amorphous polymers continuously formed by the alteration of soil minerals(1-3). Our objective is to understand how nano-organomineral complexes (nCOMx) are structured at the nanoscale, assess mechanisms of their formation, and quantify the effects of their occurrence on SOM turnovers. Due to inherent high complexity of natural samples, our methodology is based on the formation of nCOMx from both synthetic systems and natural mineral-weathered components. For the mineral component, biotite (from Bancroft, Canada) was selected. For the organic component, 3,4-Dihydroxy-L-phenylalanine, an amino acid with hydroxyl (pKa=9.95), carboxyl (pKa=2,58), amino (pKa=9,24) and an aromatic functions was chosen. The methodology aimed at developing conditions that generate biotite dissolution and nCOMx precipitation. The second step of the experiment consisted of the precipitation of nCOMx by slowly increasing pH over 3 to 12 hours of hydrolysis. Three final pH conditions were tested (4.2, 5 and 7) with Metal/Carbon ratios of 0.01, 0.1, 1, 10 and 'No Carbon'. The first results of dissolution rates and congruency, AFM imaging, ICPMS, HR-TEM and XRD as well as XAS characterizations (transmission and florescence mode at the Fe K-edge) of nCOMx will be presented. Experiments and analysis techniques were designed to study these synthetic phases with regard to Si, Al, Fe and OM proportions to increase the OM proportion (as in natural soil phases) and also increase the stability of the OM phase (as in increased residence time of OM in the soil). We will focus particularly on the Fe state

  8. The effect of UV treatment on highly polluted and normal operated swimming pools

    DEFF Research Database (Denmark)

    Spiliotopoulou, Aikaterini; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    2017-01-01

    Water samples from 2 indoor public swimming pool facilities with significantly different organic matter concentrations in the recirculation were tested to evaluate UV-induced effects on water chemistry. The aim of the study was to investigate the impact of poor water quality due to increased...

  9. Preliminary assessment of mercury accumulation in Massachusetts and Minnesota seasonal forest pools

    Science.gov (United States)

    Robert T. Brooks; Susan L. Eggert; Keith H. Nislow; Randall K. Kolka; Celia Y. Chen; Darren M. Ward

    2012-01-01

    Seasonal forest pools (SFPs) are common, widespread, and provide critical habitat for amphibians and invertebrates. The ephemeral hydrology of SFPs has been identified as an important factor in the production of biologically active methylmercury (MeHg). To investigate mercury (Hg) in SFPs, we collected water, fine benthic organic matter (FBOM), detrital materials, and...

  10. CLUSTER ANALYSIS UNTUK MEMPREDIKSI TALENTA PEMAIN BASKET MENGGUNAKAN JARINGAN SARAF TIRUAN SELF ORGANIZING MAPS (SOM

    Directory of Open Access Journals (Sweden)

    Gregorius Satia Budhi

    2008-01-01

    Full Text Available Basketball World has grown rapidly as the time goes on. This is signed by many competition and game all over the world. With the result there are many basketball players with their different playing characteristics. Demand for a coach or scout to look for or search great players to make a solid team as a coach requirement. With this application, a coach or scout will be helped in analyzing in decision making. This application uses Self Organizing Maps algorithm (SOM for Cluster Analysis. The real NBA player data is used for competitive learning or training process and real player data from Indonesian or Petra Christian University Basketball Players is used for testing process. The NBA Player data is prepared through cleaning process and then is transformed into a form that can be processed by SOM Algorithm. After that, the data is clustered with the SOM algorithm. The result of that clusters is displayed into a form that is easy to view and analyze. This result can be saved into a text file. By using the output / result of this application, that are the clusters of NBA player, the user can see the statistics of each cluster. With these cluster statistics coach or scout can predict the statistic and the position of a testing player who is in the same cluster. This information can give a support for the coach or scout to make a decision. Abstract in Bahasa Indonesia : Dunia bola basket telah berkembang dengan pesat seiring dengan berjalannya waktu. Hal ini ditandai dengan munculnya berbagai macam dan jenis kompetisi dan pertandingan baik dunia maupun dalam negeri. Sehingga makin banyak dilahirkannya pemain berbakat dengan berbagai karakteristik permainan yang berbeda. Tuntutan bagi seorang pelatih/pemandu bakat, untuk dapat melihat secara jeli dalam memenuhi kebutuhan tim untuk membentuk tim yang solid. Dengan dibuatnya aplikasi ini, maka akan membantu proses analisis dan pengambilan keputusan bagi pelatih maupun pemandu bakat Aplikasi ini

  11. Integrating plant litter quality, soil organic matter stabilization, and the carbon saturation concept.

    Science.gov (United States)

    Castellano, Michael J; Mueller, Kevin E; Olk, Daniel C; Sawyer, John E; Six, Johan

    2015-09-01

    Labile, 'high-quality', plant litters are hypothesized to promote soil organic matter (SOM) stabilization in mineral soil fractions that are physicochemically protected from rapid mineralization. However, the effect of litter quality on SOM stabilization is inconsistent. High-quality litters, characterized by high N concentrations, low C/N ratios, and low phenol/lignin concentrations, are not consistently stabilized in SOM with greater efficiency than 'low-quality' litters characterized by low N concentrations, high C/N ratios, and high phenol/lignin concentrations. Here, we attempt to resolve these inconsistent results by developing a new conceptual model that links litter quality to the soil C saturation concept. Our model builds on the Microbial Efficiency-Matrix Stabilization framework (Cotrufo et al., 2013) by suggesting the effect of litter quality on SOM stabilization is modulated by the extent of soil C saturation such that high-quality litters are not always stabilized in SOM with greater efficiency than low-quality litters. © 2015 John Wiley & Sons Ltd.

  12. Lean i Norge : opplever norske bedrifter som er mer lean, større økning i kundetilfredshet enn de som er mindre lean?

    OpenAIRE

    Fagereng, Hanne Eline; Askevold, Elisabeth Cathrine

    2010-01-01

    Vi ønsker å måle i hvor stor grad norske bedrifter har implementert lean, og for å måle grad av lean har vi utviklet et rammeverk basert på lean teori. Hovedformålet med lean er å øke kundeverdi med minst mulig ressursbruk, anstrengelse, energi, utstyr, tid, plass, material og kapital (Womack, Roos and Jones 2007). Vi vil utforske om høyere grad av lean fører til mer tilfredse kunder enn de som har lavere grad av lean. Altså om hovedformålet med lean blir oppnådd hvis man implementerer lean i...

  13. D matter

    International Nuclear Information System (INIS)

    Shiu, Gary; Wang Liantao

    2004-01-01

    We study the properties and phenomenology of particlelike states originating from D branes whose spatial dimensions are all compactified. They are nonperturbative states in string theory and we refer to them as D matter. In contrast to other nonperturbative objects such as 't Hooft-Polyakov monopoles, D-matter states could have perturbative couplings among themselves and with ordinary matter. The lightest D particle (LDP) could be stable because it is the lightest state carrying certain (integer or discrete) quantum numbers. Depending on the string scale, they could be cold dark matter candidates with properties similar to that of WIMPs or wimpzillas. The spectrum of excited states of D matter exhibits an interesting pattern which could be distinguished from that of Kaluza-Klein modes, winding states, and string resonances. We speculate about possible signatures of D matter from ultrahigh energy cosmic rays and colliders

  14. Diffuse-reflectance fourier-transform mid-infrared spectroscopy as a method of characterizing changes in soil organic matter

    Science.gov (United States)

    Diffuse-Reflectance Fourier-Transform Mid-Infrared Spectroscopy (MidIR) can identify the presence of important organic functional groups in soil organic matter (SOM). Soils contain myriad organic and inorganic components that absorb in the MidIR so spectral interpretation needs to be validated in or...

  15. Changes in soil organic matter compositrion after introduction of riparian vegetation on shores of hydroelectric reservoires (Southeast of Brazil)

    NARCIS (Netherlands)

    Alcantara, de F.A.; Buurman, P.; Curi, N.; Furtini Neto, A.E.; Lagen, van B.; Meijer, E.M.

    2004-01-01

    This work is part of a research program with the general objective of evaluating soil sustainability in areas surrounding hydroelectric reservoirs, which have been planted with riparian forest. The specific aims were: (i) to assess if and how the soil organic matter (SOM) chemical composition has

  16. Soil organic matter dynamics in Mediterranean A-horizons-The use of analytical pyrolysis to ascertain land-use history

    NARCIS (Netherlands)

    Schellekens, J.; Barbera, G.G.; Buurman, P.; Perez-Jorda, G.; Martinez-Cortizas, A.

    2013-01-01

    In archaeology and nature conservation studies, knowledge about (pre)historical land-use is important. The molecular composition of soil organic matter (SOM) supplies information about its history, as its composition is controlled by input material and decay processes. In this study, the molecular

  17. The use of radiocarbon to constrain current and future soil organic matter turnover and transport in a temperate forest

    NARCIS (Netherlands)

    Braakhekke, M.C.; Beer, C.; Schrumpf, M.; Ahrens, B.; Hoosbeek, M.R.; Kruijt, B.; Kabat, P.; Reichstein, M.; Ekici, A.

    2014-01-01

    We investigated the merits of radiocarbon measurements for estimating soil organic matter (SOM) turnover and vertical transport for a temperate deciduous forest in Germany. Eleven parameters, defining decomposition and transport in the soil carbon model SOMPROF, were estimated using a Bayesian

  18. Organic management and cover crop species steer soil microbial community structure and functionality along with soil organic matter properties

    NARCIS (Netherlands)

    Martínez-García, Laura B.; Korthals, Gerard; Brussaard, Lijbert; Jørgensen, Helene Bracht; Deyn, de Gerlinde B.

    2018-01-01

    It is well recognized that organic soil management stimulates bacterial biomass and activity and that including cover crops in the rotation increases soil organic matter (SOM). Yet, to date the relative impact of different cover crop species and organic vs. non-organic soil management on soil

  19. Soil organic matter chemistry changes upon secondary succession in Imperata Grasslands , Indonesia: A pyrolysis - GC/MS study

    NARCIS (Netherlands)

    Yassir, I.; Buurman, P.

    2012-01-01

    The chemical composition of soil organic matter (SOM) following secondary succession in Imperata grassland was investigated by Pyrolysis-Gas Chromatography/Mass Spectrometry (GC/MS). We studied 46 samples from different stages of succession using plots that last burned 3 and 9 years previously,

  20. Tracing the source of soil organic matter eroded from temperate forest catchments using carbon and nitrogen isotopes

    Science.gov (United States)

    Emma P. McCorkle; Asmeret Asefaw Berhe; Carolyn T. Hunsaker; Dale W. Johnson; Karis J. McFarlane; Marilyn L. Fogel; Stephen C. Hart

    2016-01-01

    Soil erosion continuously redistributes soil and associated soil organic matter (SOM) on the Earth's surface, with important implications for biogeochemical cycling of essential elements and terrestrial carbon sequestration. Despite the importance of soil erosion, surprisingly few studies have evaluated the sources of eroded carbon (C). We used natural abundance...

  1. Thermokarst dynamics and soil organic matter characteristics controlling initial carbon release from permafrost soils in the Siberian Yedoma region

    DEFF Research Database (Denmark)

    Weiss, Niels; Blok, Daan; Elberling, Bo

    2016-01-01

    This study relates soil organic matter (SOM) characteristics to initial soil incubation carbon release from upper permafrost samples in Yedoma region soils of northeastern Siberia, Russia. Carbon (C) and nitrogen (N) content, carbon to nitrogen ratios (C:N), δ13C and δ15N values show clear trends...

  2. Pyrolysis-gas chromatography/mass spectrometry of soil organic matter extracted from a Brazilian mangrove and Spanish salt marshes

    NARCIS (Netherlands)

    Perobelli Ferreira, F.; Buurman, P.; Macias, F.; Otero, X.L.; Boluda, R.

    2009-01-01

    The soil organic matter (SOM) extracted under different vegetation types from a Brazilian mangrove (Pai Matos Island, São Paulo State) and from three Spanish salt marshes (Betanzos Ría and Corrubedo Natural Parks, Galícia, and the Albufera Natural Park, Valencia) was investigated by pyrolysis-gas

  3. Climate change predicted to negatively influence surface soil organic matter of dryland cropping systems in the Inland Pacific Northwest, USA

    Science.gov (United States)

    Soil organic matter (SOM) is a key indicator of agricultural productivity and overall soil health. Currently, dryland cropping systems of the inland Pacific Northwest (iPNW) span a large gradient in mean annual temperature (MAT) and precipitation (MAP).These climatic drivers are major determinants o...

  4. Soil organic matter composition and quality across fire severity gradients in coniferous and deciduous forests of the southern boreal region

    Science.gov (United States)

    Jessica R. Miesel; William C. Hockaday; Randy Kolka; Philip A. Townsend

    2015-01-01

    Recent patterns of prolonged regional drought in southern boreal forests of the Great Lakes region, USA, suggest that the ecological effects of disturbance by wildfire may become increasingly severe. Losses of forest soil organic matter (SOM) during fire can limit soil nutrient availability and forest regeneration. These processes are also influenced by the composition...

  5. Guide for decontaminating swimming pool at schools

    International Nuclear Information System (INIS)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-01

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  6. Current operating practices of nuclear insurance pools

    International Nuclear Information System (INIS)

    O'Connell, J.M.

    1993-01-01

    This paper discusses the nuclear pooling system and co-operation between the pools, present practice and capacity, with a breakdown of the limits for third party liability and material damage. The author also describes the relationship between the pools and the nuclear operators (the policyholders), and concludes that the nuclear pools have been successful in serving the interests of their member companies, their policyholders and the governments as they have provided a stable insurance market by making available capacity in amounts that had never before been assembled and placed at risk in a single location. 2 tabs

  7. Guide for decontaminating swimming pool at schools

    Energy Technology Data Exchange (ETDEWEB)

    Matsuhashi, Shimpei; Kurikami, Hiroshi; Yasuda, Ryo; Takano, Takao; Seko, Noriaki; Naganawa, Hirochika; Kuroki, Ryota; Saegusa, Jun

    2012-07-15

    Because of TEPCO Fukushima Dai-ichi Nuclear Power Plant accident due to the Great East Japan Earthquake, a huge amount of radioactive materials was widely dispersed and precipitated into the environment. Swimming pools in Fukushima prefectures were contaminated with the radioactives. We JAEA carried out several demonstration tests to decontaminate the radioactives and discharge the pool water safely. We concluded the results obtained from the tests as 'Guide for decontaminating Swimming Pool at School' and released it quickly. Following this, we also released the guide in English. This manuscript, as an experimental report of the swimming pool water decontamination, is consisted from the guide in Japanese and English prepared. (author)

  8. Structure for nuclear fuel storage pools

    International Nuclear Information System (INIS)

    Ebata, Sakae; Nichiei, Shinji.

    1979-01-01

    Purpose: To enable leak detection in nuclear fuel storage pools, as well as prevent external leakages while keeping the strength of the constructional structures. Constitution: Protection plates are provided around pool linear plates and a leak reception is provided to the bottom. Leakages are detected by leak detecting pipeways and the external leakages are prevented by collecting them in a detection area provided in the intermediate layer. Since ferro-reinforcements at the bottom wall of the pool are disconnected by the protection plate making it impossible to form the constructional body, body hunches are provided to the bottom wall of the pool for processing the ferro-reinforcements. (Yoshino, Y.)

  9. Heat transfer from internally heated hemispherical pools

    International Nuclear Information System (INIS)

    Gabor, J.D.; Ellsion, P.G.; Cassulo, J.C.

    1980-01-01

    Experiments were conducted on heat transfer from internally heated ZnSO 4 -H 2 O pools to the walls of hemispherical containers. This experimental technique provides data for a heat transfer system that has to date been only theoretically treated. Three different sizes of copper hemispherical containers were used: 240, 280, 320 mm in diameter. The pool container served both as a heat transfer surface and as an electrode. The opposing electrode was a copper disk, 50 mm in diameter located at the top of the pool in the center. The top surface of the pool was open to the atmosphere

  10. Formation of trihalomethanes as disinfection byproducts in herbal spa pools.

    Science.gov (United States)

    Fakour, Hoda; Lo, Shang-Lien

    2018-04-09

    Herbal spa treatments are favorite recreational activities throughout the world. The water in spas is often disinfected to control pathogenic microorganisms and guarantee hygiene. However, chlorinated water may cause the formation of disinfection byproducts (DBPs). Although there have been many studies on DBP formation in swimming pools, the role of organic matter derived from herbal medicines applied in herbal spa water has been largely neglected. Accordingly, the present study investigated the effect of herbal medicines on the formation of trihalomethanes (THMs) in simulated herbal spa water. Water samples were collected from a spa pool, and then, disinfection and herbal addition experiments were performed in a laboratory. The results showed that the organic molecules introduced by the herbal medicines are significant precursors to the formation of THMs in spa pool water. Since at least 50% of THMs were produced within the first six hours of the reaction time, the presence of herbal medicines in spa water could present a parallel route for THM exposure. Therefore, despite the undeniable benefits of herbal spas, the effect of applied herbs on DBP formation in chlorinated water should be considered to improve the water quality and health benefits of spa facilities.

  11. Dark Matter

    International Nuclear Information System (INIS)

    Holt, S. S.; Bennett, C. L.

    1995-01-01

    These proceedings represent papers presented at the Astrophysics conference in Maryland, organized by NASA Goddard Space Flight Center and the University of Maryland. The topics covered included low mass stars as dark matter, dark matter in galaxies and clusters, cosmic microwave background anisotropy, cold and hot dark matter, and the large scale distribution and motions of galaxies. There were eighty five papers presented. Out of these, 10 have been abstracted for the Energy Science and Technology database

  12. Endogeic earthworms shape bacterial functional communities and affect organic matter mineralization in a tropical soil

    Science.gov (United States)

    Bernard, Laetitia; Chapuis-Lardy, Lydie; Razafimbelo, Tantely; Razafindrakoto, Malalatiana; Pablo, Anne-Laure; Legname, Elvire; Poulain, Julie; Brüls, Thomas; O'Donohue, Michael; Brauman, Alain; Chotte, Jean-Luc; Blanchart, Eric

    2012-01-01

    Priming effect (PE) is defined as a stimulation of the mineralization of soil organic matter (SOM) following a supply of fresh organic matter. This process can have important consequences on the fate of SOM and on the management of residues in agricultural soils, especially in tropical regions where soil fertility is essentially based on the management of organic matter. Earthworms are ecosystem engineers known to affect the dynamics of SOM. Endogeic earthworms ingest large amounts of soil and assimilate a part of organic matter it contains. During gut transit, microorganisms are transported to new substrates and their activity is stimulated by (i) the production of readily assimilable organic matter (mucus) and (ii) the possible presence of fresh organic residues in the ingested soil. The objective of our study was to see (i) whether earthworms impact the PE intensity when a fresh residue is added to a tropical soil and (ii) whether this impact is linked to a stimulation/inhibition of bacterial taxa, and which taxa are affected. A tropical soil from Madagascar was incubated in the laboratory, with a 13C wheat straw residue, in the presence or absence of a peregrine endogeic tropical earthworm, Pontoscolex corethrurus. Emissions of 12CO2 and 13CO2 were followed during 16 days. The coupling between DNA-SIP (stable isotope probing) and pyrosequencing showed that stimulation of both the mineralization of wheat residues and the PE can be linked to the stimulation of several groups especially belonging to the Bacteroidetes phylum. PMID:21753801

  13. Dynamics of inorganic nutrients in intertidal sediments: porewater, exchangeable and intracellular pools

    Directory of Open Access Journals (Sweden)

    Emilio eGarcia-Robledo

    2016-05-01

    Full Text Available The study of inorganic nutrients dynamics in shallow sediments usually focuses on two main pools: the porewater (PW nutrients and the exchangeable (EX ammonium and phosphate. Recently, it has been found that microphytobenthos (MPB and other microorganisms can accumulate large amounts of nutrients intracellularly (IC, highlighting the biogeochemical importance of this nutrient pool. Storing nutrients could support the growth of autotrophs when nutrients are not available, and could also provide alternative electron acceptors for dissimilatory processes such as nitrate reduction. Here, we studied the magnitude and relative importance of these three nutrient pools (PW, IC and EX and their relation to chlorophylls (used as a proxy for MPB abundance and organic matter (OM contents in an intertidal mudflat of Cadiz Bay (Spain. MPB was localized in the first 4 mm of the sediment and showed a clear seasonal pattern; highest chlorophylls content was found during autumn and lowest during spring-summer. The temporal and spatial distribution of nutrients pools and MPB were largely correlated. Ammonium was higher in the IC and EX fractions, representing on average 59 and 37% of the total ammonium pool, respectively. Similarly, phosphate in the IC and EX fractions accounted on average for 40 and 31% of the total phosphate pool, respectively. Nitrate in the PW was low, suggesting low nitrification activity and rapid consumption. Nitrate accumulated in the IC pool during periods of moderate MPB abundance, being up to 66% of the total nitrate pool, whereas it decreased when chlorophyll concentration peaked likely due to a high nitrogen demand. EX-Nitrate accounted for the largest fraction of total sediment nitrate, 66% on average. The distribution of EX-Nitrate was significantly correlated with chlorophyll and OM, which probably indicates a relation of this pool to an increased availability of sites for ionic adsorption. This EX-Nitrate pool could represent an

  14. Dark Matter

    International Nuclear Information System (INIS)

    Bashir, A.; Cotti, U.; De Leon, C. L.; Raya, A; Villasenor, L.

    2008-01-01

    One of the biggest scientific mysteries of our time resides in the identification of the particles that constitute a large fraction of the mass of our Universe, generically known as dark matter. We review the observations and the experimental data that imply the existence of dark matter. We briefly discuss the properties of the two best dark-matter candidate particles and the experimental techniques presently used to try to discover them. Finally, we mention a proposed project that has recently emerged within the Mexican community to look for dark matter

  15. Characterisation of landfill leachate by EEM-PARAFAC-SOM during physical-chemical treatment by coagulation-flocculation, activated carbon adsorption and ion exchange.

    Science.gov (United States)

    Oloibiri, Violet; De Coninck, Sam; Chys, Michael; Demeestere, Kristof; Van Hulle, Stijn W H

    2017-11-01

    The combination of fluorescence excitation-emission matrices (EEM), parallel factor analysis (PARAFAC) and self-organizing maps (SOM) is shown to be a powerful tool in the follow up of dissolved organic matter (DOM) removal from landfill leachate by physical-chemical treatment consisting of coagulation, granular activated carbon (GAC) and ion exchange. Using PARAFAC, three DOM components were identified: C1 representing humic/fulvic-like compounds; C2 representing tryptophan-like compounds; and C3 representing humic-like compounds. Coagulation with ferric chloride (FeCl 3 ) at a dose of 7 g/L reduced the maximum fluorescence of C1, C2 and C3 by 52%, 17% and 15% respectively, while polyaluminium chloride (PACl) reduced C1 only by 7% at the same dose. DOM removal during GAC and ion exchange treatment of raw and coagulated leachate exhibited different profiles. At less than 2 bed volumes (BV) of treatment, the humic components C1 and C3 were rapidly removed, whereas at BV ≥ 2 the tryptophan-like component C2 was preferentially removed. Overall, leachate treated with coagulation +10.6 BV GAC +10.6 BV ion exchange showed the highest removal of C1 (39% - FeCl 3 , 8% - PACl), C2 (74% - FeCl 3 , 68% - PACl) and no C3 removal; whereas only 52% C2 and no C1 and C3 removal was observed in raw leachate treated with 10.6 BV GAC + 10.6 BV ion exchange only. Analysis of PARAFAC-derived components with SOM revealed that coagulation, GAC and ion exchange can treat leachate at least 50% longer than only GAC and ion exchange before the fluorescence composition of leachate remains unchanged. Copyright © 2017 Elsevier Ltd. All rights reserved.

  16. Ulikhet som impuls for nye oppdagelser i dans: Å tøye både muskler og meninger gjennom mangfold i Danselaboratoriet

    Directory of Open Access Journals (Sweden)

    Tone Pernille Østern

    2014-12-01

    Full Text Available I denne artikkelen har forfatterne fokus på hvordan ulikhet mellom mennesker kan fungere som en impuls som bidrar til meningsskaping, nye oppdagelser og transformasjon i improvisasjon i dans. Artikkelen tar utgangspunkt i Østerns avhandling ”Meaning-making in the Dance Laboratory. Exploring dance improvisation with differently bodied dancers” (2009. I artikkelen vever forfatterne sammen sine ulike stemmer. Tone Pernille Østerns perspektiv er som initiativtaker og tidligere koreograf-dansepedagog i Danselaboratoriet, mens Elen Øyens perspektiv er som danser i den samme gruppen. Øyen er danser og rullestolbruker. Hovedkonklusjonen i artikkelen er at gjennom å forstå ulikhet som en verdi og impuls til å møtes og skape i improvisasjon i dans, så kan deltakerne i gruppen gjennomgå kraftfulle transformative endringsprosesser når det gjelder synet på ”den andre”. Dette har en betydning som går langt ut over det konkrete, kunstneriske undervisningsrommet. ”Den andre” forstås i artikkelen som en konstruksjon som både muliggjør adskillelse og utestenging fra et fellesskap, men også som en mulighet til å forstå at ”den andre” ikke nødvendigvis er, eller skal være, som meg.

  17. Soil Response to Natural Vegetation Dynamics During the Late Holocene in Minnesota, USA, and Implications for SOM Accumulation and Loss

    Science.gov (United States)

    Mason, J. A.; Kasmerchak, C. S.; Keita, H.; Gruley, K. E.

    2016-12-01

    We studied soil response to late Holocene shifts in the dynamic boundary between forest and grassland, in two contrasting landscapes of Minnesota, USA. On both the glaciated landscape of northwestern Minnesota and steep bedrock slopes of southeastern Minnesota, forest has replaced grassland in the late Holocene (after 4 ka in the NW, during at least the last few 100 yr in the SE). Two distinct soil morphologies coexist in essentially the same climate and parent materials, Mollisols with deep SOM accumulation under grassland and Alfisols with most SOM in thin A horizons under forest. Organic carbon stocks of the Mollisols we sampled (to 1 m depth) are at least 50% greater than those of the Alfisols; thus, replacement of grassland by forest involves substantial SOM loss. Ultimately, the transition from Alfisols to Mollisols can probably be explained by much lower proportions of belowground SOM addition, and possibly less bioturbation, under forest; however, the timescale of this change is of great interest. Mollisols and transitional soils occur under forest today near the 19th century location of the vegetation boundary in NW Minnesota, and in certain slope positions in SE Minnesota. Stable C isotope profiles within those soils record the transition from C4 or mixed C3/C4 vegetation (tallgrass prairie or savanna) to C3 forest vegetation. Combined with 14C dating these data demonstrate a substantial lag in loss of the Mollisol morphology—thick SOM-rich A horizons with highly stable aggregates—after forest occupation. In fact, these thick A horizons may persist even when C4 grass-derived SOM has largely been replaced by SOM added after forest occupation. We are exploring possible explanations for this persistence in NW Minnesota. In SE Minnesota, it is likely related to parent material rich in dolomite fragments, with stable aggregation and SOM accumulation favored by abundant Ca2+and Mg2+. This parent material effect results in localization of high SOM

  18. 40 år gamle kvinner som bruker hormonregimer – sunne utvalg eller risikogrupper?

    Directory of Open Access Journals (Sweden)

    Sidsel Graff-Iversen

    2009-11-01

    Full Text Available  SAMMENDRAGFormålet med denne artikkelen var å studere brukerne av kombinerte antikonsepsjonsmidler, regimer med progesteronalene og østrogensubstitusjon blant norske 40-åringer. Var det først og fremst lavrisikogrupper – friske ogrøykfrie kvinner – som brukte p-piller av kombinasjonstype, slik gjeldende anbefalinger råder til? Var progesteronbrukerneet utvalg av særlig helsebevisste kvinner? Hvor utbredt var bruken av østrogen i denne aldersgruppen?Var det tegn til at østrogenbrukerne er en “healthy selection”, slik utenlandske studier har vist?Materialet er fra 40-åringsundersøkelser i 11 norske fylker i tiden 1997-99. Resultatene viser at 3,5% avkvinnene brukte kombinerte antikonseptiva og at disse utgjorde et “sunt utvalg” med lave andeler røykere og godhelse. De 9,4% av kvinnene som brukte progesteron alene, skilte seg derimot lite fra premenopausale kvinner utenhormonbruk. De 2,4% av kvinnene som brukte østrogen, hadde mindre god helse, høyere andel røykere og lavereutdanningsnivå, sammenlignet med premenopausale kvinner. Men sammenligning innen gruppen av post- og perimenopausalekvinner viste ingen vesentlig forskjell mellom østrogenbrukerne og andre. Resultatet fra den førstekontrollerte studien av østrogen og hjertesykdom kom i 1998, men førte ikke til noen påviselig forskjell i seleksjonentil østrogenbruk fra 1997 til 1999.Konklusjonen er at kvinnene som brukte kombinerte antikonseptiva i 40-årsalderen var en “sunn seleksjon” itråd med det som blir anbefalt, mens de som brukte progesteron alene skilte seg lite ut fra kvinner som ikke bruktehormoner. Kvinner som brukte østrogen i denne unge alderen, sto fram som en helsemessig risikogruppe imaterialet som helhet, men skilte seg lite ut fra andre antatt post- eller perimenopausale kvinner i 40-årsalderen.Graff-Iversen, S. 40-year old female sex hormone users: healthy selections or risk groups? Results fromhealth surveys in 11 Norwegian

  19. Two-dimensional NMR spectroscopy as a tool to link soil organic matter composition to ecosystem processes

    Science.gov (United States)

    Soucemarianadin, Laure; Erhagen, Björn; Öquist, Mats; Nilsson, Mats; Schleucher, Jürgen

    2014-05-01

    Environmental factors (e.g. temperature and moisture) and the size and composition of soil microbial populations are often considered the main drivers of soil organic matter (SOM) mineralization. Less consideration is given to the role of SOM as a substrate for microbial metabolism and the importance of the organo-chemical composition of SOM on decomposition. In addition, a fraction of the SOM is often considered as recalcitrant to mineralization leading to accumulation of SOM. However, recently the concept of intrinsic recalcitrance of SOM to mineralization has been questioned. The challenge in investigating the role of SOM composition on its mineralization to a large extent stems from the difficulties in obtaining high resolution characterization of a very complex matrix. 13C nuclear magnetic resonance (NMR) spectroscopy is a widely used tool to characterize SOM. However, SOM is a very complex mixture and in the resulting 13C NMR spectra, the identified functional groups may represent different molecular fragments that appear in the same spectral region leading to broad peaks. These overlaps defy attempts to identify molecular moieties, and this makes it impossible to derive information at a resolution needed for evaluating e.g. recalcitrance of SOM. Here we applied a method, developed in wood science for the pulp paper industry, to achieve a better characterization of SOM. We directly dissolved finely ground organic layers of boreal forest floors-litters, fibric and humic horizons of both coniferous and broadleaved stands-in dimethyl sulfoxide and analyzed the resulting solution with a two-dimensional (2D) 1H-13C NMR experiment. We will discuss methodological aspects related to the ability to identify and quantify individual molecular moieties in SOM. We will demonstrate how the spectra resolve signals of CH groups in a 2D plane determined by the 13C and 1H chemical shifts, thereby vastly increasing the resolving power and information content of NMR spectra. The

  20. Distribution and elevated soil pools of mercury in an acidic subtropical forest of southwestern China

    International Nuclear Information System (INIS)

    Zhou, Jun; Wang, Zhangwei; Zhang, Xiaoshan; Chen, Jian

    2015-01-01

    Tieshanping catchment in southwest China was supposed to a large pool of atmospheric mercury. This work was aimed to examine THg (total mercury) concentrations, pools and influence factors in the acidic forest. THg concentrations were highly elevated in the study area, which was significantly depended on TOM (total organic matter) concentrations and altitudinal elevation, whereas negatively correlated with soil pH. The pools of mercury accumulated in soils were correlated strongly with the stocks of TOM and altitude, ranged from 5.9 to 32 mg m −2 and averaged 14.5 mg m −2 , indicating that the acidic forest was a great sink of atmospheric mercury in southwest China. THg concentrations in stream waters decreased with altitude increasing and regression analyses showed that soil/air exchange flux would be increased with the decrease of altitude. Present results suggest that elevation increasing decreases THg losses as low THg concentrations in runoffs and volatilization from soils. - Highlights: • Soil THg pools and influence factors were studied at an acidic catchment in southwestern China. • THg concentrations was increased significantly with TOM concentrations and altitude increasing, decreased with pH. • THg pools in soils were highly elevated and deepened on TOM pools and altitude. • Difference in THg output by volatilization and runoff was a major reason for THg distribution at different altitudes. - Mercury pools increased with altitude increasing as mercury lost more at low elevation area in acidic subtropical forest

  1. Oxidation kinetics of corium pool

    Energy Technology Data Exchange (ETDEWEB)

    Sulatsky, A.A., E-mail: andrei314@mail.ru [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Smirnov, S.A. [D.V. Efremov Scientific Research Institute of Electrophysical Apparatus (NIIEFA), St. Petersburg (Russian Federation); Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Kotova, S.Yu. [Alexandrov Research Institute of Technologies (NITI), Sosnovy Bor (Russian Federation); Fischer, M.; Hellmann, S. [AREVA NP GmbH, Erlangen (Germany); Tromm, W.; Miassoedov, A. [Forschungzentrum Karlsruhe (FZK), Karlsruhe (Germany); Bottomley, D. [EUROPÄISCHE KOMMISSION, Joint Research Centre Institut für Transurane (ITU), Karlsruhe (Germany); Piluso, P. [CEA Cadarache-DEN/DTN/STRI, St.Paul-lez-Durance (France); Barrachin, M. [Institut de Radioprotection et Sûreté Nucléaire, St.Paul-lez-Durance (France)

    2013-09-15

    Highlights: • The analysis of experimental data on molten corium oxidation was been carried out. • The analysis has revealed the main factors influencing the oxidation kinetics. • The analysis was used for developing a qualitative analytical model. • The numerical modeling has confirmed the results of experimental data analysis. -- Abstract: Experimental, theoretical and numerical studies of oxidation kinetics of an open surface corium pool have been reported. The experiments have been carried out within OECD MASCA program and ISTC METCOR, METCOR-P and EVAN projects. It has been shown that the melt oxidation is controlled by an oxidant supply to the melt free surface from the atmosphere, not by the reducer supply from the melt. The project experiments have not detected any input of the zirconium oxidation kinetics into the process chemistry. The completed analysis puts forward a simple analytical model, which gives an explanation of the main features of melt oxidation process. The numerical modeling results are in good agreement with experimental data and theoretical considerations.

  2. Oxidation kinetics of corium pool

    International Nuclear Information System (INIS)

    Sulatsky, A.A.; Smirnov, S.A.; Granovsky, V.S.; Khabensky, V.B.; Krushinov, E.V.; Vitol, S.A.; Kotova, S.Yu.; Fischer, M.; Hellmann, S.; Tromm, W.; Miassoedov, A.; Bottomley, D.; Piluso, P.; Barrachin, M.

    2013-01-01

    Highlights: • The analysis of experimental data on molten corium oxidation was been carried out. • The analysis has revealed the main factors influencing the oxidation kinetics. • The analysis was used for developing a qualitative analytical model. • The numerical modeling has confirmed the results of experimental data analysis. -- Abstract: Experimental, theoretical and numerical studies of oxidation kinetics of an open surface corium pool have been reported. The experiments have been carried out within OECD MASCA program and ISTC METCOR, METCOR-P and EVAN projects. It has been shown that the melt oxidation is controlled by an oxidant supply to the melt free surface from the atmosphere, not by the reducer supply from the melt. The project experiments have not detected any input of the zirconium oxidation kinetics into the process chemistry. The completed analysis puts forward a simple analytical model, which gives an explanation of the main features of melt oxidation process. The numerical modeling results are in good agreement with experimental data and theoretical considerations

  3. Use of stable isotope techniques in soil organic matter studies

    International Nuclear Information System (INIS)

    Gerzabek, M.H.

    1998-01-01

    method in estimating absolute rates of mineralisation, immobilisation, nitrification and nitrate reduction in soil, which cannot be directly deduced from non-tracer experiments. A very interesting topic seems to be the measurement of nitrogen released from organic residues, like N-fixing plants, sewage sludge or other manures. Further potential of stable isotope techniques in SOM dynamics studies can be envisaged in the field of quantitating the pools contributing to N-mineralization, the role of soil microbial biomass in this context, the sulphur cycle ( 34 S), climate change and the impact of nitrogen oxide pollution on SOM dynamics, especially in semi-natural environments

  4. Linking measurements of biodegradability, thermal stability and chemical composition to evaluate the effects of management on soil organic matter

    Science.gov (United States)

    Gregorich, Ed; Gillespie, Adam; Beare, Mike; Curtin, Denis; Sanei, Hamed; Yanni, Sandra

    2015-04-01

    The stability of soil organic matter (SOM) as it relates to resistance to microbial degradation has important implications for nutrient cycling, emission of greenhouse gases, and C sequestration. Hence, there is interest in developing new ways to accurately quantify and characterise the labile and stable forms of soil organic C. Our objectives in this study were to evaluate and describe relationships among the biodegradability, thermal stability and chemistry of SOM in soil under widely contrasting management regimes. Samples from the same soil under permanent pasture, an arable cropping rotation, and chemical fallow were fractionated (sand: 2000-50 μm; silt: 50-5 μm, and clay: managements and that sand-associated organic matter was significantly more susceptible than that in the silt or clay fractions. Analysis by XANES showed accumulation of carboxylates and strong depletion of amides (protein) and aromatics in the fallow whole soil. Moreover, protein depletion was most significant in the sand fraction of the fallow soil. Sand fractions in fallow and cropped soils were, however, enriched in plant-derived phenols, aromatics and carboxylates compared to the sand fraction of pasture soils. In contrast, ketones, which have been identified as products of microbially-processed organic matter, were slightly enriched in the silt fraction of the pasture soil. These data suggest reduced inputs and cropping restrict the decomposition of plant residues and, without supplemental N additions, protein-N in native SOM is significantly mineralized in fallow systems to meet microbial C mineralization demands. Analytical pyrolysis showed distinct differences in the thermal stability of SOM among the size fractions and management treatments; it also showed that the loss of SOM generally involved dehydrogenation. The temperature at which half of the C was pyrolyzed showed strong correlation with mineralizable C and thus provides solid evidence for a link between the biological and

  5. 13 CFR 120.1708 - Pool Certificates.

    Science.gov (United States)

    2010-01-01

    ... United States. (c) SBA purchase of a Loan Interest. SBA will determine whether to purchase a Loan... reserves the right to purchase a Loan Interest from a Pool at any time. (d) Self-liquidating. A Pool... market conditions and program experience, and will publish any such change in the Federal Register. (h...

  6. Compact fuel storage rack for fuel pools

    International Nuclear Information System (INIS)

    Parras, F.; Louvat, J.P.

    1986-01-01

    ETS LEMER and FRAMATOME propose a new compact storage rack. This rack permits a considerable increase of the storage capacity of cooling pools. A short description of the structure and the components is presented, to propose racks that are: . Inalterable, . Compact, . Insensitive to earthquakes. Installation in pools already in operation is simplified by their light structure and the bearing device [fr

  7. The warm pool in the Indian Ocean

    Digital Repository Service at National Institute of Oceanography (India)

    Vinayachandran, P.N.; Shetye, S.R.

    is larger and warmer, a peculiarity of the pool in the Indian Ocean is its seasonal variation. The surface area of the pool changes from 24 x 106 km2 in April to 8 x 106 km2 in September due to interaction with the southwest monsoon. The annual cycles of sea...

  8. Shedding Light on Dark Liquidity Pools

    NARCIS (Netherlands)

    Degryse, H.A.; van Achter, M.; Wuyts, G.

    2008-01-01

    This article reviews the recent developments on dark liquidity pools starting from the theoretical and empirical academic literature. The number of dark liquidity pools as well as their trading volume has grown substantially in the last couple of years. We highlight the incentives of providers as

  9. Bearing performance degradation assessment based on time-frequency code features and SOM network

    International Nuclear Information System (INIS)

    Zhang, Yan; Tang, Baoping; Han, Yan; Deng, Lei

    2017-01-01

    Bearing performance degradation assessment and prognostics are extremely important in supporting maintenance decision and guaranteeing the system’s reliability. To achieve this goal, this paper proposes a novel feature extraction method for the degradation assessment and prognostics of bearings. Features of time-frequency codes (TFCs) are extracted from the time-frequency distribution using a hybrid procedure based on short-time Fourier transform (STFT) and non-negative matrix factorization (NMF) theory. An alternative way to design the health indicator is investigated by quantifying the similarity between feature vectors using a self-organizing map (SOM) network. On the basis of this idea, a new health indicator called time-frequency code quantification error (TFCQE) is proposed to assess the performance degradation of the bearing. This indicator is constructed based on the bearing real-time behavior and the SOM model that is previously trained with only the TFC vectors under the normal condition. Vibration signals collected from the bearing run-to-failure tests are used to validate the developed method. The comparison results demonstrate the superiority of the proposed TFCQE indicator over many other traditional features in terms of feature quality metrics, incipient degradation identification and achieving accurate prediction. Highlights • Time-frequency codes are extracted to reflect the signals’ characteristics. • SOM network served as a tool to quantify the similarity between feature vectors. • A new health indicator is proposed to demonstrate the whole stage of degradation development. • The method is useful for extracting the degradation features and detecting the incipient degradation. • The superiority of the proposed method is verified using experimental data. (paper)

  10. En teoretisk utdyping av rom og materialitet som pedagogisk ressurs i barnehagen

    Directory of Open Access Journals (Sweden)

    Solveig Nordtømme

    2015-07-01

    Full Text Available Abstract: This article is a theoretical exploration with the aim of discussing an ontological basis for space and materiality as educational resources in kindergarten. Attention is directed on children’s play experiences interacting with space and materiality, and how children use and create space. The metaphors front stage, space in between, and backstage (inspired from Erving Goffman, 1969, which form the study's main findings, are used as the backdrop for the issue and analyzes. The empirical material used in this exploration has been collected with an ethnographic methodological approach in two kindergartens. Maurice Merleau-Ponty’s (1962 focus on bodily experience and presence in space, along with concepts from Latour’s (2005 actor-network theory, is used to explore the data. The article contributes with theoretical tools for professionals in kindergarten teaching, to shed light on the importance of space, materiality and play in children's everyday life in kindergarten.Sammendrag: Denne artikkelen diskuterer et ontologisk grunnlag og er en teoretisk utforskning av rom og materialitet som en pedagogisk ressurs i barnehagen. Oppmerksomheten er rettet mot barns lekeerfaringer i samspill med rom og materialitet, og hvordan barn bruker og skaper rom. Metaforene hovedrom, mellomrom, og bakrom (inspirert fra Erving Goffman, 1969, som danner studiens hovedfunn, blir brukt som et bakteppe for problemstilling og analyser av det empiriske materialet fra to barnehager. Maurice Merleau-Ponty publikasjoner The Phenomenology of Perception (Merleau-Ponty, 1962 med sitt fokus på kroppslig erfaring i levd rom, blir brukt sammen med begreper fra Latours aktør-nettverksteori (Latour 2005 til å utforske hvordan rom og materialitet kan være pedagogiske ressurser. Artikkelens kunnskapsbidrag er å presentere et teoretisk verktøy for barnehageprofesjonen og kunnskaper om lekens betydning i barns hverdag i barnehagen.

  11. Big city consultants shut down our pool : a shocking community pool gets checked for stray voltage

    Energy Technology Data Exchange (ETDEWEB)

    Lynch, P. [Power Line Systems Engineering Inc., Markham, ON (Canada)

    2009-12-15

    This article discussed an investigation conducted at a community pool where swimmers complained of receiving electrical shocks both in the pool and on the pool's deck area. Electrical measurements taken at the pool revealed current flows from the pool water to various points around the deck area. Measured current flow in the pool area was 30 amps even when the main pool service breaker was opened to shut off power to the entire facility. Thirty amps of primary neutral current was then measured on the primary side aerial neutral in front of the pool. A 10 amp primary feeder from the pool joined up with the complex's primary neutral wire to increase the neutral current to 40 amps. The combined 40 amps current then returned to the secondary side of a nearby utility transformer substation. The study showed that the underground wet low-resistance grounded surface area of the pool was attracting the 30 amps of utility current from the surrounding ground area. The local utility disconnected the primary and secondary neutral interconnection at the pool's main 600-volt step-down transformer. The pool deck was removed in order to install additional copper bonding grounds. In order to avert serious injuries, many experts propose that all electric utilities should be required by law to reconfigure their power systems to prevent primary power neutral currents from entering private buildings. 1 tab., 2 figs.

  12. Ripples in a superconducting tidal pool

    CERN Document Server

    Hudson, E

    2003-01-01

    The behaviour of electrons in a metal is often compared to that of water in a pool. An empty pool is like a material that has all of its electrons removed. As electrons are 'poured' into the metal, they first occupy the lowest energies available - the bottom of the pool - and eventually fill up to the Fermi energy, the top of the pool. At this point we no longer discuss electrons but quasiparticles. These are electrons that have modified properties due to their interactions within the material. Waves in a pool can be excited, and their properties will depend on the depth of the water. Similarly in a metal, quasiparticles behave like waves that have a material-dependent dispersion relation between their energy and their wavevector, which specifies their direction and wavelength. This simple analogy also hints at an indirect method of measuring the dispersion relation of a metal, and hence the myriad of properties that depend on it. (U.K.)

  13. Palaeocene-early Eocene inversion of the Phuquoc-Kampot Som Basin

    DEFF Research Database (Denmark)

    Fyhn, Michael B. W.; Pedersen, Stig A.S.; Boldreel, Lars Ole

    2010-01-01

    /Pb analysis is used to unravel the basin history. This reveals a hitherto unknown earliest Palaeogene basin inversion associated with the Luconian suturing to SE Asia and the shutdown of palaeo-Pacific subduction underneath SE Asia. The Phuquoc–Kampot Som Basin and the Khorat Basin in Thailand constitute...... the erosional remnants of a larger basin that covered large parts of SE Asia in Late Mesozoic time, and subsequently became segregated during earliest Palaeogene inversion and erosion. Inversion was focused along the several hundred kilometres long Kampot and Khmer–Chanthaburi fold belts that confine...

  14. En bok for meg? Litteraturvalg med knyttneveprøven som metode.

    OpenAIRE

    Nyhus, Mari

    2016-01-01

    Sammendrag Denne masteroppgaven har følgende problemstilling: Kan elever gjennom en strukturert metode klare å finne egnet litteratur på biblioteket på egenhånd? Studien oppgaven bygger på har til hensikt å undersøke om elever klarer å finne seg egnet litteratur på skolebiblioteket på egenhånd. Forskning viser at elever som leser på egenhånd for å utvikle lesingen sin, trenger tekster på et umiddelbart lesenivå. Det vil si at elevene skal forstå og kunne avkode 94% av ordene de leser. (Frost ...

  15. Fatigue Level Estimation of Bill Based on Acoustic Signal Feature by Supervised SOM

    Science.gov (United States)

    Teranishi, Masaru; Omatu, Sigeru; Kosaka, Toshihisa

    Fatigued bills have harmful influence on daily operation of Automated Teller Machine(ATM). To make the fatigued bills classification more efficient, development of an automatic fatigued bill classification method is desired. We propose a new method to estimate bending rigidity of bill from acoustic signal feature of banking machines. The estimated bending rigidities are used as continuous fatigue level for classification of fatigued bill. By using the supervised Self-Organizing Map(supervised SOM), we estimate the bending rigidity from only the acoustic energy pattern effectively. The experimental result with real bill samples shows the effectiveness of the proposed method.

  16. Impact of soil organic matter on the distribution of polycyclic aromatic hydrocarbons (PAHs) in soils

    International Nuclear Information System (INIS)

    Yang, Y.; Zhang, N.; Xue, M.; Tao, S.

    2010-01-01

    The knowledge on the distribution of hydrophobic organic contaminants in soils can provide better understanding for their fate in the environment. In the present study, the n-butanol extraction and humic fractionation were applied to investigate the impact of SOM on the distribution of polycyclic aromatic hydrocarbons (PAHs). The results indicated that 80.5%-94.8% of the target PAHs could be extracted by n-butanol and 63.1%-94.6% of PAHs were associated with fulvic acid (FA). Concentrations of un-extracted PAHs increased significantly with the increasing soil organic matter (SOM), however, such an association was absent for the extractable fractions. The results suggested that the sequestration played a critical role in the accumulation of PAHs in soils. SOM also retarded the diffusion of PAHs into the humin fractions. It implied that sequestration in SOM was critical for PAH distribution in soils, while the properties of PAH compounds also had great influences. - Soil organic matter played an important role in the distribution of PAHs in soils through sequestration.

  17. Soil organic matter dynamics in a North America tallgrass prairie after 9 yr of experimental warming

    Directory of Open Access Journals (Sweden)

    X. Cheng

    2011-06-01

    Full Text Available The influence of global warming on soil organic matter (SOM dynamics in terrestrial ecosystems remains unclear. In this study, we combined soil fractionation with isotope analyses to examine SOM dynamics after nine years of experimental warming in a North America tallgrass prairie. Soil samples from the control plots and the warmed plots were separated into four aggregate sizes (>2000 μm, 250–2000 μm, 53–250 μm, and <53 μm, and three density fractions (free light fraction – LF, intra-aggregate particulate organic matter – iPOM, and mineral-associated organic matter – mSOM. All fractions were analyzed for their carbon (C and nitrogen (N content, and δ13C and δ15N values. Warming did not significantly effect soil aggregate distribution and stability but increased C4-derived C input into all fractions with the greatest in LF. Warming also stimulated decay rates of C in whole soil and all aggregate sizes. C in LF turned over faster than that in iPOM in the warmed soils. The δ15N values of soil fractions were more enriched in the warmed soils than those in the control, indicating that warming accelerated loss of soil N. The δ15N values changed from low to high, while C:N ratios changed from high to low in the order LF, iPOM, and mSOM due to increased degree of decomposition and mineral association. Overall, warming increased the input of C4-derived C by 11.6 %, which was offset by the accelerated loss of soil C. Our results suggest that global warming simultaneously stimulates C input via shift in species composition and decomposition of SOM, resulting in negligible net change in soil C.

  18. Design and Construction of Pool Door for Research Reactor

    Energy Technology Data Exchange (ETDEWEB)

    Jung, Kwangsub; Lee, Sangjin; Choi, Jinbok; Oh, Jinho; Lee, Jongmin [KAERI, Daejeon (Korea, Republic of)

    2016-05-15

    The pool door is a structure to isolate the reactor pool from the service pool for maintenance. The pool door is installed before the reactor pool is drained. The pool door consists of structural component and sealing component. The main structures of the pool door are stainless steel plates and side frames. The plates and frames are assembled by welded joints. Lug is welded at the top of the plate. The pool door is submerged in the pool water when it is used. Materials of the pool door should be resistive to corrosion and radiation. Stainless steel is used in structural components and air nozzle assemblies. Features of design and construction of the pool door for the research reactor are introduced. The pool door is designed to isolate the reactor pool for maintenance. Structural analysis is performed to evaluate the structural integrity during earthquake. Tests and inspections are also carried out during construction to identify the safety and function of the pool door.

  19. Design and Construction of Pool Door for Research Reactor

    International Nuclear Information System (INIS)

    Jung, Kwangsub; Lee, Sangjin; Choi, Jinbok; Oh, Jinho; Lee, Jongmin

    2016-01-01

    The pool door is a structure to isolate the reactor pool from the service pool for maintenance. The pool door is installed before the reactor pool is drained. The pool door consists of structural component and sealing component. The main structures of the pool door are stainless steel plates and side frames. The plates and frames are assembled by welded joints. Lug is welded at the top of the plate. The pool door is submerged in the pool water when it is used. Materials of the pool door should be resistive to corrosion and radiation. Stainless steel is used in structural components and air nozzle assemblies. Features of design and construction of the pool door for the research reactor are introduced. The pool door is designed to isolate the reactor pool for maintenance. Structural analysis is performed to evaluate the structural integrity during earthquake. Tests and inspections are also carried out during construction to identify the safety and function of the pool door

  20. Pool scrubbing models for iodine components

    Energy Technology Data Exchange (ETDEWEB)

    Fischer, K [Battelle Ingenieurtechnik GmbH, Eschborn (Germany)

    1996-12-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs.

  1. Pool scrubbing models for iodine components

    International Nuclear Information System (INIS)

    Fischer, K.

    1996-01-01

    Pool scrubbing is an important mechanism to retain radioactive fission products from being carried into the containment atmosphere or into the secondary piping system. A number of models and computer codes has been developed to predict the retention of aerosols and fission product vapours that are released from the core and injected into water pools of BWR and PWR type reactors during severe accidents. Important codes in this field are BUSCA, SPARC and SUPRA. The present paper summarizes the models for scrubbing of gaseous Iodine components in these codes, discusses the experimental validation, and gives an assessment of the state of knowledge reached and the open questions which persist. The retention of gaseous Iodine components is modelled by the various codes in a very heterogeneous manner. Differences show up in the chemical species considered, the treatment of mass transfer boundary layers on the gaseous and liquid sides, the gas-liquid interface geometry, calculation of equilibrium concentrations and numerical procedures. Especially important is the determination of the pool water pH value. This value is affected by basic aerosols deposited in the water, e.g. Cesium and Rubidium compounds. A consistent model requires a mass balance of these compounds in the pool, thus effectively coupling the pool scrubbing phenomena of aerosols and gaseous Iodine species. Since the water pool conditions are also affected by drainage flow of condensate water from different regions in the containment, and desorption of dissolved gases on the pool surface is determined by the gas concentrations above the pool, some basic limitations of specialized pool scrubbing codes are given. The paper draws conclusions about the necessity of coupling between containment thermal-hydraulics and pool scrubbing models, and proposes ways of further simulation model development in order to improve source term predictions. (author) 2 tabs., refs

  2. Removal of volatile iodine from gas bubbles rising in water pools: review and assessment of pool scrubbing codes

    International Nuclear Information System (INIS)

    Polo, J.; Herranz, L.E.; Peyres, V.; Escudero, M.

    1996-01-01

    During a hypothetical nuclear reactor accident with core damage the fission products released from the degrading fuel bundles often pass through aqueous beds before entering the containment, mitigating in part the source term. Several computer codes have been developed for predicting the fission product and aerosols removal in pool scrubbing scenarios. In addition to particle removal, these codes simulate the retention of some volatile iodine compounds. Nonetheless, experimental data on the matter are rather scarce and further validation remains to be done. In this work a review of volatile iodine removal models included in SPARC and BUSCA codes is presented. Besides, the results and discussions of a validation of both codes against the available experimental data are summarized. SPARC and BUSCA codes model the diffusion of iodine toward the bubble interface by using the film penetration theory, which assumes a double layer gas-liquid at the interface. However, there are some differences between the two models, mainly related to the boundary conditions in the aqueous volume for the diffusion of molecular iodine. In SPARC, a set of fast reactions in the liquid phase control both the molecular iodine concentration in the pool and the partition coefficient of iodine at the interface. Thus, the aqueous chemistry plays an important role in the boundary conditions for the diffusion process. On the contrary, the BUSCA model has no chemical considerations at all, and assumes a null iodine concentration in the water bulk. Several sensitivity studies have been made in order to weight the effect of these differences. The variables examined in these studies were the pool temperature and the incoming iodine concentration in the pool. Additionally, sensitivity studies focused on the steam mass fraction of the injected gas were performed to study the effect of the different approach of both models for the condensation process. The results showed a different sensitivity of SPARC

  3. Solid-state 13C NMR experiments reveal effects of aggregate size on the chemical composition of particulate organic matter in grazed steppe soils

    Science.gov (United States)

    Steffens, M.; Kölbl, A.; Kögel-Knabner, I.

    2009-04-01

    Grazing is one of the most important factors that may reduce soil organic matter (SOM) stocks and subsequently deteriorate aggregate stability in grassland topsoils. Land use management and grazing reduction are assumed to increase the input of OM, improve the soil aggregation and change species composition of vegetation (changes depth of OM input). Many studies have evaluated the impact of grazing cessation on SOM quantity. But until today little is known about the impact of grazing cessation on the chemical quality of SOM in density fractions, aggregate size classes and different horizons. The central aim of this study was to analyse the quality of SOM fractions in differently sized aggregates and horizons as affected by increased inputs of organic matter due to grazing exclusion. We applied a combined aggregate size, density and particle size fractionation procedure to sandy steppe topsoils with different organic matter inputs due to different grazing intensities (continuously grazed = Cg, winter grazing = Wg, ungrazed since 1999 = Ug99, ungrazed since 1979 = Ug79). Three different particulate organic matter (POM; free POM, in aggregate occluded POM and small in aggregate occluded POM) and seven mineral-associated organic matter fractions were separated for each of three aggregate size classes (coarse = 2000-6300 m, medium = 630-2000 m and fine =

  4. Application of TAM III to study sensitivity of soil organic matter degradation to temperature

    Science.gov (United States)

    Vikegard, Peter; Barros, Nieves; Piñeiro, Verónica

    2014-05-01

    Traditionally, studies of soil biodegradation are based on CO2 dissipation rates. CO2 is a product of aerobic degradation of labile organic substrates like carbohydrates. That limits the biodegradation concept to just one of the soil organic matter fractions. This feature is responsible for some problems to settle the concept of soil organic matter (SOM) recalcitrance and for controversial results defining sensitivity of SOM to temperature. SOM consists of highly complex macromolecules constituted by fractions with different chemical nature and redox state affecting the chemical nature of biodegradation processes. Biodegradation of fractions more reduced than carbohydrates take place through metabolic pathways that dissipate less CO2 than carbohydrate respiration, that may not dissipate CO2, or that even may uptake CO2. These compounds can be considered more recalcitrant and with lower turnover times than labile SOM just because they are degraded at lower CO2 rates that may be just a consequence of the metabolic path. Nevertheless, decomposition of every kind of organic substrate always releases heat. For this reason, the measurement of the heat rate by calorimetry yields a more realistic measurement of the biodegradation of the SOM continuum. TAM III is one of the most recent calorimeters designed for directly measuring in real time the heat rate associated with any degradation process. It is designed as a multichannel system allowing the concomitant measurement of to up 24 samples at isothermal conditions or through a temperature scanning mode from 18 to 100ºC, allowing the continous measure of any sample at controlled non-isothermal conditions. The temperature scanning mode was tested in several soil samples collected at different depths to study their sensitivity to temperature changes from 18 to 35 ºC calculating the Q10 and the activation energy (EA) by the Arrhenius equation. It was attempted to associate the obtained EA values with the soil thermal

  5. Gaseous Matter

    CERN Document Server

    Angelo, Joseph A

    2011-01-01

    aseous Matter focuses on the many important discoveries that led to the scientific interpretation of matter in the gaseous state. This new, full-color resource describes the basic characteristics and properties of several important gases, including air, hydrogen, helium, oxygen, and nitrogen. The nature and scope of the science of fluids is discussed in great detail, highlighting the most important scientific principles upon which the field is based. Chapters include:. Gaseous Matter An Initial Perspective. Physical Characteristics of Gases. The Rise of the Science of Gases. Kinetic Theory of

  6. Swimming pool hydraulics and their significance for public pools. Bedeutung der Beckenhydraulik in oeffentlichen Schwimmbaedern

    Energy Technology Data Exchange (ETDEWEB)

    Gansloser, G

    1989-11-01

    The term of swimming pool hydraulics means the process of letting in and drawing off water to and from the pool while ensuring that no inadmissible water-borne contaminant concentrations will occur anywhere within the pool. Measurements were performed on a pool to study the significance of correct pool hydraulics. The author points out that a wrong water recirculation design will bring to nought the effects of an elaborate water treatment system; by contrast, poor pool water quality can be greatly improved by redesigning the pool water hydraulics approach. In principle, systems with with water inlet at one side and water outlet at the far side will fall short of hygienic requirements. (BWI).

  7. Studies of thermal stratification in water pool

    International Nuclear Information System (INIS)

    Verma, P.K.; Chandraker, D.K.; Nayak, A.K.; Vijayan, P.K.

    2015-01-01

    Large water pools are used as a heat sink for various cooling systems used in industry. In context of advance nuclear reactors like AHWR, it is used as ultimate heat sink for passive systems for decay heat removal and containment cooling. This system incorporates heat exchangers submerged in the large water pool. However, heat transfer by natural convection in pool poses a problem of thermal stratification. Due to thermal stratification hot layers of water accumulate over the relatively cold one. The heat transfer performance of heat exchanger gets deteriorated as a hot fluid envelops it. In the nuclear reactors, the walls of the pool are made of concrete and it may subject to high temperature due to thermal stratification which is not desirable. In this paper, a concept of employing shrouds around the heat source is studied. These shrouds provide a bulk flow in the water pool, thereby facilitating mixing of hot and cold fluid, which eliminate stratification. The concept has been applied to the a scaled model of Gravity Driven Water Pool (GDWP) of AHWR in which Isolation Condensers (IC) tubes are submerged for decay heat removal of AHWR using ICS and thermal stratification phenomenon was predicted with and without shrouds. To demonstrate the adequacy of the effectiveness of shroud arrangement and to validate the simulation methodology of RELAP5/Mod3.2, experiments has been conducted on a scaled model of the pool with and without shroud. (author)

  8. Spent fuel pool cleanup and stabilization

    International Nuclear Information System (INIS)

    Miller, R.L.

    1987-06-01

    Each of the plutonium production reactors at Hanford had a large water-filled spent fuel pool to provide interim storage of irradiated fuel while awaiting shipment to the separation facilities. After cessation of reactor operations the fuel was removed from the pools and the water levels were drawn down to a 5- to 10-foot depth. The pools were maintained with the water to provide shielding and radiological control. What appeared to be a straightforward project to process the water, remove the sediments from the basin, and stabilize the contamination on the floors and walls became a very complex and time consuming operation. The sediment characteristics varied from pool to pool, the ion exchange system required modification, areas of hard-pack sediments were discovered on the floors, special arrangements to handle and package high dose rate items for shipment were required, and contract problems ensued with the subcontractor. The original schedule to complete the project from preliminary engineering to final stabilization of the pools was 15 months. The actual time required was about 25 months. The original cost estimate to perform the work was $2,651,000. The actual cost of the project was $5,120,000, which included $150,000 for payment of claims to the subcontractor. This paper summarizes the experiences associated with the cleanup and radiological stabilization of the 100-B, -C, -D, and -DR spent fuel pools, and discusses a number of lessons learned items

  9. Rommet som den tredje pedagog - En studie av pedagogers forståelse av rommets betydning - med fokus på estetisk virksomhet

    OpenAIRE

    Krokstad, Inger Elisabeth

    2014-01-01

    Masteroppgaven «Rommet som den tredje pedagog i tre Reggio Emilia-inspirerte barnehager. En studie av pedagogers forståelse av rommets betydning –med fokus på estetisk virksomhet» har til hensikt å bidra til økt kunnskap om estetisk virksomhet som er forbundet med Reggio Emilias tanke om rommet som den tredje pedagog. Avhandlingens problemstilling er: Hvilke mønster kan identifiseres i barnehagepedagogens forståelse av rommet som den tredje pedagog-med fokus på estetisk virksomhet? ...

  10. Multi-digit handwritten sindhi numerals recognition using som neural network

    International Nuclear Information System (INIS)

    Chandio, A.A.; Jalbani, A.H.; Awan, S.A.

    2017-01-01

    In this research paper a multi-digit Sindhi handwritten numerals recognition system using SOM Neural Network is presented. Handwritten digits recognition is one of the challenging tasks and a lot of research is being carried out since many years. A remarkable work has been done for recognition of isolated handwritten characters as well as digits in many languages like English, Arabic, Devanagari, Chinese, Urdu and Pashto. However, the literature reviewed does not show any remarkable work done for Sindhi numerals recognition. The recognition of Sindhi digits is a difficult task due to the various writing styles and different font sizes. Therefore, SOM (Self-Organizing Map), a NN (Neural Network) method is used which can recognize digits with various writing styles and different font sizes. Only one sample is required to train the network for each pair of multi-digit numerals. A database consisting of 4000 samples of multi-digits consisting only two digits from 10-50 and other matching numerals have been collected by 50 users and the experimental results of proposed method show that an accuracy of 86.89% is achieved. (author)

  11. Proactive Review som læringsrum for online-ledere

    DEFF Research Database (Denmark)

    Kolbæk, Ditte

    2017-01-01

    . Kapitlet undersøger, hvordan online lederen kan lære af erfaringer skabt i hans/hendes online team. Kapitlet tager udgangspunkt i Engeströms virksomhedsteori og Proactive Review som praksisser for, hvordan ledere konkret kan lære sammen med deres team (Kolbæk 2011). Kapitlet udvikler en model for lederens...... læring på basis af ovenstående teorier. Da læring og kommunikation i teamet foregår online, er det nærliggende at benytte netnografi som metodisk tilgang. Kapitlet undersøger online lederens læringsrum i en global IT virksomhed, hvor Proactive Reviews er implementeret i flere end 40 lande......, at medarbejdere og ledere opholder sig i forskellige lande, og at de kun sjældent eller måske aldrig mødes fysisk, men altid samarbejder og kommunikerer online. Kapitlet kalder det online teams og online ledelse. Dette kapitel fokuserer på lederens læring i et læringsrum, hvor ledelse og samarbejde foregår online...

  12. Brand management og den refleksive forbruger - med semiotik som hjælpedisciplin

    DEFF Research Database (Denmark)

    Hermansen, Judy

    2009-01-01

      Kritisk eftertanke er et væsentligt træk ved den refleksive forbruger - ofte parret med en vis negativitet overfor et brand, en reklame eller forbrugerisme i al almindelighed. Den refleksive forbrugertype kommer til udtryk hos for eksempel en anti-branding guru som Naomi Klein og hendes...... bestseller bog "No Logo" eller i græsrodsbevægelsen Adbusters ( https://www.adbusters.org/ ), der efterhånden i mange år har udsendt et månedsmagasin med kritik af forbrugersamfundet og al dets reklame og branding. Disse anti-forbrugs og anti-branding bevægelser udspringer af, og er identifikationspunkter...... - den refleksive forbruger skal have noget, der kan "brande" ham som anderledes end alle mainstreamforbrugerne. Den refleksive forbruger er med andre ord en Feinschmecker og i lighed med - eller måske rettere i endnu højere grad end - alle andre forbrugere signalerer den refleksive forbruger sin...

  13. Hvad kan du tilbyde mig som muslim, præst?

    DEFF Research Database (Denmark)

    Skovsgaard, Steen

    2005-01-01

    . islam og kristendom var jeg i 1995 inviteret til et møde med en stor gruppe muslimer i Gellerup. Det var et debatmøde om islam og kristendom, hvor skoleleder og imam Abdul Wahid Pedersen og jeg skulle komme med oplæg og debattere. Og så kunne der efterfølgende stilles spørgsmål fra salen. Det var hér...... andre mennesker, eller om Gud elsker dig og vil ha’ noget med dig at gøre, den dag må du love mig at komme tilbage. For så har jeg noget at tilbyde dig. Indtil da må du nøjes med islam!” Et sådant svar ville ganske vist ha’ været længere, men der ville også ha’ været mere for den unge muslim at tænke på...... og overkommelige krav, som stilles dig i islam. Selv her har du svigtet og er skyldig! Skyldig til dom og til straf!”. Og hvis så muslimen skulle finde på at sige, at han da bestemt har opfyldt Guds vilje iflg. islam, så kan vi jo passende fortælle ham, at de krav som stilles i islam kun er en bleg...

  14. Tester og testtilbakemeldinger som direkte bidragsytere til dypere læring blant studenter

    Directory of Open Access Journals (Sweden)

    Henrik Herrebrøden

    2014-11-01

    Full Text Available Denne artikkelen diskuterer forskning som tilsier at tester og testtilbakemeldinger kan bidra til dypere læring blant studenter. Testing har vist seg å forbedre langtidshukommelsen av innlært kunnskap sammenlignet med repetert lesing, noe som kalles for testeffekten. For at testeffekten skal optimaliseres, bør tester utformes med mål om å bidra til dyp prosessering av innlært kunnskap. Testtilbakemeldingers rolle i utdanning kan være å bidra til økt metakognitiv selvregulering blant studenter. For at selvregulering skal promoteres best mulig, bør testtilbakemeldinger inneholde utdypende informasjon. Samlet ser tester og testtilbakemeldinger ut til å være nyttige læringsverktøy og potensielle bidragsytere til dypere læring blant studenter.AbstractThis article discusses research supporting that tests and test feedback are learning tools that may promote deeper learning among students. Testing improves long-term retention of knowledge compared to repeated study, a phenomenon known as the testing effect. In order to promote the testing effect, tests should facilitate deep processing of knowledge among students. Test feedback has the potential to increase students’ metacognitive self-regulation. For this type of metacognition to be enhanced, feedback should contain elaborate information. Conclusively, tests and test feedback appear to be valuable learning tools and potential promoters of deeper learning.

  15. Praksisnær skoleudvikling og PLC som strategisk udviklingsaktør

    DEFF Research Database (Denmark)

    Christensen, Ole; Bach, Anna

    2017-01-01

    I det følgende belyses, hvorledes PLC kan udvikles som strategisk udviklingsaktør og understøtte praksisnær skoleudvikling. Vi ønsker at belyse hvorledes Bekendtgørelsens overordnede intentioner kan få retning og rammer og dermed medvirke til, at hele det pædagogiske personale indgår i skoleudvik......I det følgende belyses, hvorledes PLC kan udvikles som strategisk udviklingsaktør og understøtte praksisnær skoleudvikling. Vi ønsker at belyse hvorledes Bekendtgørelsens overordnede intentioner kan få retning og rammer og dermed medvirke til, at hele det pædagogiske personale indgår i...... skoleudviklingen. I den forbindelse er det vores erfaring, at PLC kan spille en central rolle i forbindelse med den praksisnære og lokale skoleudvikling. Erfaringerne bygger især på udviklings- og forskningsprojekter fra kommunerne Kolding, København, Roskilde og Tårnby. Der har været tale om praksisnære...

  16. Designtænkning som didaktisk metode: Læringsdesign for teknologisk forestillingskraft og handlekraft

    Directory of Open Access Journals (Sweden)

    Rikke Berggreen Paaskesen

    2016-11-01

    Full Text Available Det er et problem, at undervisere, lærerstuderende og elever ikke bliver mødt med tilstrækkelig inspiration, metoder og design til, hvorledes de kan anvende teknologier i undervisningen på måder der understøtter teknologisk forestillingskraft, handlekraft og kritisk-kreativ teknologisk dannelse. Dette forsøger denne artikel at adressere gennem at tilbyde forståelsesramme, struktur, procesmodel og konkret case-eksempel for hvorledes man kan arbejde med designtænkning som didaktisk metode til udformning læringsdesign for kritisk-kreativ teknologisk forestillingskraft og handlekraft. Artiklen kobler designtænkning og læringsdesign sammen til designtænkende læringsdesign for undervisere og læringsdesign for designtænkning for studerende og elever. Disse formater beskrives dernæst som åbne didaktisk-pædagogiske læringsdesign og centrale strukturer, elementer og faser fremstilles og beskrives. Pædagogisk tænkning for kritisk-kreativt medborgerskab inddrages til at underbygge modellens didaktisk-pædagogiske potentiale. Designtænkende læringsdesign for demokratisk dannelse præsenteres dernæst gennem en konkret case Future-Tech-Town Year 2060. I konklusionen udvides perspektivet til uddannelsesarbejde med læringsdesign der sigter mod kritisk-kreative fremtids-skabere med teknologier.

  17. Distributed Technologies in a Data Pool

    Science.gov (United States)

    Keiser, K.; Conover, H.; Graves, S.; He, Y.; Regner, K.; Smith, M.

    2004-12-01

    A Data Pool is an on-line repository providing interactive and programmatic access to data products through a variety of services. The University of Alabama in Huntsville has developed and deployed such a Data Pool in conjunction with the DISCOVER project, a collaboration with NASA and Remote Sensing Systems. DISCOVER provides long-term ocean and climate data from a variety of passive microwave satellite instruments, including such products as sea-surface temperature and wind, air temperature, atmospheric water vapor, cloud water and rain rate. The Data Pool provides multiple methods to access and visualize these products, including conventional HTTP and FTP access, as well as data services that provide for enhanced usability and interoperability, such as GridFTP, OPeNDAP, OpenGIS-compliant web mapping and coverage services, and custom subsetting and packaging services. This paper will focus on the distributed service technologies used in the Data Pool, which spans heterogeneous machines at multiple locations. For example, in order to provide seamless access to data at multiple sites, the Data Pool provides catalog services for all data products at the various data server locations. Under development is an automated metadata generation tool that crawls the online data repositories regularly to dynamically update the Data Pool catalog with information about newly generated data files. For efficient handling of data orders across distributed repositories, the Data Pool also implements distributed data processing services on the file servers where the data resides. Ontologies are planned to support automated service chaining for custom user requests. The UAH Data Pool is based on a configurable technology framework that integrates distributed data services with a web interface and a set of centralized database services for catalogs and order tracking. While this instantiation of the Data Pool was implemented to meet the needs of the DISCOVER project, the framework was

  18. Destruction of disinfection byproducts and their precursors in swimming pool water by combined UV treatment and ozonation

    DEFF Research Database (Denmark)

    Cheema, Waqas Akram; Kaarsholm, Kamilla Marie Speht; Andersen, Henrik Rasmus

    Both UV treatment and ozonation are used to reduce different types of disinfection byproducts (DBP) in swimming pools. UV treatment is most common as it is particularly efficient in removing the repulsive chlorine like smelling chloramines (combined chlorine). UV treatment of a pool water increased...... chlorine reactivity and formation of chlor-organic DBP such as trihalomethanes. Based on the similar selective reactivity of ozone and chlorine we hypothesized that the created reactivity towards chlorine by UV treatment of dissolved organic matter in pool water might also be expressed as an increased...... reactivity towards ozone and that ozonation might saturate the chlorine reactivity created by UV treatment and mitigate the increased DBP formation. By experimentally treating pool water samples, we found that UV treatment makes pool water highly reactive to ozone. The created reactivity towards chlorine...

  19. A Pool of Distant Galaxies

    Science.gov (United States)

    2008-11-01

    Anyone who has wondered what it might be like to dive into a pool of millions of distant galaxies of different shapes and colours, will enjoy the latest image released by ESO. Obtained in part with the Very Large Telescope, the image is the deepest ground-based U-band image of the Universe ever obtained. It contains more than 27 million pixels and is the result of 55 hours of observations with the VIMOS instrument. A Sea of Galaxies ESO PR Photo 39/08 A Pool of Distant Galaxies This uniquely beautiful patchwork image, with its myriad of brightly coloured galaxies, shows the Chandra Deep Field South (CDF-S), arguably the most observed and best studied region in the entire sky. The CDF-S is one of the two regions selected as part of the Great Observatories Origins Deep Survey (GOODS), an effort of the worldwide astronomical community that unites the deepest observations from ground- and space-based facilities at all wavelengths from X-ray to radio. Its primary purpose is to provide astronomers with the most sensitive census of the distant Universe to assist in their study of the formation and evolution of galaxies. The new image released by ESO combines data obtained with the VIMOS instrument in the U- and R-bands, as well as data obtained in the B-band with the Wide-Field Imager (WFI) attached to the 2.2 m MPG/ESO telescope at La Silla, in the framework of the GABODS survey. The newly released U-band image - the result of 40 hours of staring at the same region of the sky and just made ready by the GOODS team - is the deepest image ever taken from the ground in this wavelength domain. At these depths, the sky is almost completely covered by galaxies, each one, like our own galaxy, the Milky Way, home of hundreds of billions of stars. Galaxies were detected that are a billion times fainter than the unaided eye can see and over a range of colours not directly observable by the eye. This deep image has been essential to the discovery of a large number of new galaxies

  20. Dark matters

    International Nuclear Information System (INIS)

    Silk, Joseph

    2010-01-01

    One of the greatest mysteries in the cosmos is that it is mostly dark. That is, not only is the night sky dark, but also most of the matter and the energy in the universe is dark. For every atom visible in planets, stars and galaxies today there exists at least five or six times as much 'Dark Matter' in the universe. Astronomers and particle physicists today are seeking to unravel the nature of this mysterious but pervasive dark matter, which has profoundly influenced the formation of structure in the universe. Dark energy remains even more elusive, as we lack candidate fields that emerge from well established physics. I will describe various attempts to measure dark matter by direct and indirect means, and discuss the prospects for progress in unravelling dark energy.