| 1. |
- Chawade, Aakash, 1980, et al.
(författare)
-
Putative cold acclimation pathways in Arabidopsis thaliana identified by a combined analysis of mRNA co-expression patterns, promoter motifs and transcription factors
- 2007
-
Ingår i: BMC GENOMICS. - : Springer Science and Business Media LLC. - 1471-2164. ; 8
-
Tidskriftsartikel (refereegranskat)abstract
- Background With the advent of microarray technology, it has become feasible to identify virtually all genes in an organism that are induced by developmental or environmental changes. However, relying solely on gene expression data may be of limited value if the aim is to infer the underlying genetic networks. Development of computational methods to combine microarray data with other information sources is therefore necessary. Here we describe one such method. Results By means of our method, previously published Arabidopsis microarray data from cold acclimated plants at six different time points, promoter motif sequence data extracted from ~24,000 Arabidopsis promoters and known transcription factor binding sites were combined to construct a putative genetic regulatory interaction network. The inferred network includes both previously characterised and hitherto un-described regulatory interactions between transcription factor (TF) genes and genes that encode other TFs or other proteins. Part of the obtained transcription factor regulatory network is presented here. More detailed information is available in the additional files. Conclusion The rule-based method described here can be used to infer genetic networks by combining data from microarrays, promoter sequences and known promoter binding sites. This method should in principle be applicable to any biological system. We tested the method on the cold acclimation process in Arabidopsis and could identify a more complex putative genetic regulatory network than previously described. However, it should be noted that information on specific binding sites for individual TFs were in most cases not available. Thus, gene targets for the entire TF gene families were predicted. In addition, the networks were built solely by a bioinformatics approach and experimental verifications will be necessary for their final validation. On the other hand, since our method highlights putative novel interactions, more directed experiments could now be performed.
|
|
| 2. |
|
|
| 3. |
- Idström, Alexander, et al.
(författare)
-
Dissolution of cellulose in tetrabutylammonium acetate/dimethyl sulfoxide
- 2016
-
Ingår i: The 7th Workshop on cellulose, regenerated cellulose and cellulose derivatives. ; , s. 15-18
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- The dissolution of cellulose in tetrabutylammonium acetate (TBAAc)/dimethyl sulfoxide (DMSO) was studied combining experimental and simulation techniques. It was found that the dissolution limit at 40 °C corresponded to a molar ratio close to one acetate per cellulose anhydroglucose units. MD simulations suggested that the acetate ions bind to cellulose by dual hydrogen bonds. This effectively turns cellulose into a polyelectrolyte, attracting the bulky tetrabutylammonium (TBA+) counter ions, which prevent close contact between chains in the dissolved state. This hypothesis was tested by 1H- and 13C-NMR spectroscopy, which confirmed that acetate forms hydrogen bonds to cellulose, and by diffusion NMR spectroscopy, which demonstrated a strong dynamic correlation between bound acetate and tetrabutylammonium in near-quantitative agreement with simulation. The present results suggest that offering hydrogen bonding to the acetate ions is the main driving force for dissolving cellulose and that the TBA+ counter ions form a diffuse layer around the acetate-decorated cellulose chains.
|
|
| 4. |
- Idström, Alexander, et al.
(författare)
-
On the dissolution of cellulose in tetrabutylammonium acetate/dimethyl sulfoxide : a frustrated solvent
- 2017
-
Ingår i: Cellulose. - : Springer Science and Business Media LLC. - 0969-0239 .- 1572-882X. ; 24:9, s. 3645-3657
-
Tidskriftsartikel (refereegranskat)abstract
- We have found that the dissolution of cellulose in the binary mixed solvent tetrabutylammonium acetate/dimethyl sulfoxide follows a previously overlooked near-stoichiometric relationship such that one dissolved acetate ion is able to dissolve an amount of cellulose corresponding to about one glucose residue. The structure and dynamics of the resulting cellulose solutions were investigated using small-angle X-ray scattering (SAXS) and nuclear magnetic resonance techniques as well as molecular dynamics simulation. This yielded a detailed picture of the dissolution mechanism in which acetate ions form hydrogen bonds to cellulose and causes a diffuse solvation sheath of bulky tetrabutylammonium counterions to form. In turn, this leads to a steric repulsion that helps to keep the cellulose chains apart. Structural similarities to previously investigated cellulose solutions in aqueous tetrabutylammonium hydroxide were revealed by SAXS measurement. To what extent this corresponds to similarities in dissolution mechanism is discussed.
|
|
| 5. |
|
|
| 6. |
|
|
| 7. |
- Olsson, Björn, et al.
(författare)
-
Förutsättningar och styrmedel för ökad elsjöfart
- 2024
-
Ingår i: Sammanställning av referat från Transportforum 2024. - Linköping : Statens väg- och transportforskningsinstitut. ; , s. 43-44
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Det finns potential att öka elektrifieringen i svensk sjöfart. Inom ramen för ett regeringsuppdrag föreslår Trafikanalys nya styrmedel för elsjöfart, bland annat skattereduktion för landström, klimatpremie för elfartyg och stöd till land- och laddinfrastruktur i hamnar. Under 2022 har Trafikanalys haft i uppdrag att dels utreda förutsättningarna för en ökad användning av helt eller delvis eldrivna fartyg i Sverige, dels utreda möjliga incitament för att åstadkomma ökad användning av land- och laddström. Resultaten från båda uppdragen redovisas här gemensamt.Vi har studerat litteraturen och utvecklingen avseende elektrifieringen av sjöfart inom Sverige, Norge och Nederländerna. Marknadspotentialen för elektrifieringen har analyserats genom energiförbrukningen för fartyg som anlöper svenska hamnar. Vi beskriver de tekniska förutsättningarna och vilka problem som är specifika för elektrifiering av sjöfart jämfört med andra trafikslag. Vi har också studerat vilka styrmedel som finns idag för elektrifiering inom sjöfart såväl som andra trafikslag. Baserat på detta har vi pekat på möjliga styrmedel med potential att öka användningen av land- och laddström, samt öka användningen av helt eller delvis eldrivna fartyg i Sverige. Vi har också låtit en referensgrupp med representanter från branschen ha synpunkter och kommentarer på vårt arbete och våra förslag till styrmedel. De förslag till styrmedel vi lyfter fram är:Skattereduktion för elanslutning för mindre fartygKlimatpremie för elfartygStöd till elanslutning för fartygUndantag från kravet på nätkoncession för hamnarTydligare klimatkrav på nationella fartygUnderlätta processen för certifiering av fartyg vid konvertering till eldriftInnovationsupphandling i regionalt upphandlad färjetrafikDet ingick i uppdraget att göra en bedömning av införande av miljözoner i hamnar. Vår uppfattning är att marknaden i Sverige idag inte är mogen för införande av miljözoner. Vi efterlyser en vidare diskussion om miljödifferentierade sjöfartsavgifter för att stimulera introduktionen av elsjöfart.
|
|
| 8. |
- Nordin, Annika, et al.
(författare)
-
Urea for sanitization of anaerobically digested dewatered sewage sludge
- 2015
-
Ingår i: Environmental Engineering Science. - : Mary Ann Liebert Inc. - 1092-8758 .- 1557-9018. ; 32:2, s. 86-94
-
Tidskriftsartikel (refereegranskat)abstract
- When recycling sewage sludge to agriculture, the risk of disease transmission must be taken into account. Sanitizing treatment prevents disease transmission by reducing dissemination of pathogens early in the reuse chain. Sanitization is commonly achieved by heat treatment of sludge, for example, by prepasteurization before anaerobic digestion or by thermophilic anaerobic digestion. This study evaluated ammonia treatment of anaerobically digested dewatered sewage sludge at pilot scale (65 ton) by urea addition at 0.85% and 1.6% wet weight compared with storage without ammonia addition over 145 days of treatment during the Swedish winter, with ambient temperatures below 0 C. Addition of 1.6% urea reduced indicator organisms Enterococcus spp. and Escherichia coli to below the detection limit of 100 and 10cfu/g, respectively, within 3 months of treatment, whereas the 0.85% urea treatment did inactivate E. coli but not Enterococcus spp. within the study period (145 days). In the control, both indicator bacteria were still present at the end of the study period. Thus, 1.6% treatment with urea is a promising low cost on-demand option for sludge sanitization and can be performed at considerably lower cost than heat treatment.
|
|
| 9. |
- Auvray, Xavier, 1986, et al.
(författare)
-
Aging of Cu/SSZ-13 for NH3 SCR in mixed lean condition
- 2018
-
Konferensbidrag (övrigt vetenskapligt/konstnärligt)abstract
- Two catalytic methods have been developed to remove the NOx emissions from diesel vehicles and comply with the emission regulations: the NOx storage and reduction process (NSR) and the reduction of NOx with NH3 (SCR). Advanced systems combining these two methods for an optimum efficiency are now studied. SCR catalysts are subjected alternating lean and rich conditions as well as to high temperatures in rich conditions during deSOx of the LNT material. The purpose of the present work is therefore to determine the response of a Cu/SSZ-13 to several aging treatments at 800°C involving rich and/or lean exposure. Deactivation was observed after all types of aging. However strong differences in deactivation degree exists between aging procedures. Lean aging, for 8h at 800°C, was the most moderate aging tested although it brought about significant activity loss below 250°C. Alternating between long lean periods and short rich periods caused slightly stronger deactivation, which was most significant at 200°C. However, the switching frequency between lean and rich had negligible influence on subsequent activity. As shown in Figure 1, SCR activity after 8h exposure in H2 was outstandingly low. It increased monotonically with temperature to reach a maximum of 58% NO conversion. Further investigation pertaining to the rich treatment was performed. The aging time was reduced to 2h and, for direct comparison, a 32h cycling aging was performed, implying a total rich time of 2h. Both samples were severely impacted over the whole temperature range. It revealed that 2h in rich conditions led to stronger deactivation than 8h in lean and lean/rich conditions, emphasizing the deterioration power of H2. Aging caused by rich conditions was so dominant that additional 30h in lean has negligible influence on SCR below 300°C. However, the long additional exposure to lean conditions lowered significantly the SCR activity between 400 and 500°C.
|
|
| 10. |
- Siesjö, Björn, et al.
(författare)
-
Inledning
- 2018
-
Ingår i: Hus mot himlen. Hållbar hybris? Olshammar, G., Olsson, K. och Siesjö, B. (red.). - Malmö : Arena. - 9789178435210
-
Bokkapitel (övrigt vetenskapligt/konstnärligt)
|
|
