| 1. |
- Gylle, A. Maria, et al.
(författare)
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Salinity effect on oxygen evolution and the relative amount of RuBisCO in the brackish Fucus vesiculosus L. (Phaeophyceae)
- 2007
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Ingår i: Pysiological responses of marine and brackish Fucuc vesiculosus L with respect to salinity. - Sundsvall : Mittuniversitetet. - 9789185317417 ; , s. 1-8
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Bokkapitel (övrigt vetenskapligt/konstnärligt)abstract
- The sublittoral Fucus vesiculosus from the brackish Bothnian Sea is adapted to a salinity of 4-5 practical salinity units (psu). This study investigated the effect of different salinities (5, 10, 20 and 35 psu) on maximum photosynthetic capacity (Pmax) and the relative amount of ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco). The results revealed a higher Pmax at higher salinities with the maximum at 10 psu. Higher salinities also resulted in increased relative amounts of Rubisco but this was not well correlated with the increased Pmax. Therefore, the amount of Rubisco doesn�t appear to be the main reason for the increased Pmax in higher salinities.
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| 2. |
- Ekelund, Nils G. A., et al.
(författare)
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In situ study of relative electron transport rates (ETR) in the marine macroalga Fucus vesiculosus from the Baltic Sea at different depths and times of the year.
- 2008
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Ingår i: Journal of Applied Phycology. - : Springer Science and Business Media LLC. - 0921-8971 .- 1573-5176. ; 20:5, s. 751-756
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Tidskriftsartikel (refereegranskat)abstract
- The brown alga Fucus vesiculous is one of the few marine species in the Baltic Sea. F. vesiculosus shows high morphological and physiological variability as a response to its environmental conditions. The salinity in the Baltic Sea is 4-5 psu in comparison to 35 psu in the Atlantic. Photosynthesis of algae is usually measured after collection and transportation to constant culture conditions. However, in this study the relative photosynthetic electron transport rate (rETR), calculated from chl a fluorescence parameters were compared for algae from 1 and 4 m depths by SCUBA divers. Measurements of light response curves from the same individuals of F. vesiculosus at different depths and times of the year have to our knowledge never been made before. Measurements were performed at four different occasions during the spring (February 25, April 3 and 29 and May 26 in 2005) in the Baltic Sea, using rapid light curves (RLCs) generated with a Diving PAM. In addition, samples were collected for photoinhibition studies in the laboratory. The light response curves obtained in situ at 1 and 4 m depths for F. vesiculosus showed lower values of light saturation with depth. When algae from 1 and 4 m depths were exposed to high irradiances of PAR (1400 µmol photons m-2 s-1), algae from 1 m depth showed a higher degree of photoinhibition in comparison to algae from the 4 m depth.
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| 3. |
- Gylle, A Maria, et al.
(författare)
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Desiccation and salinity effects on marine and brackhish Fucus vesiculosus L. (Phaeophyceae).
- 2009
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Ingår i: Phycologia. - : Informa UK Limited. - 0031-8884 .- 2330-2968. ; 48:3, s. 156-164
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)abstract
- Ecotypes of Fucus vesiculosus L. from the Norwegian Sea (34 psu, marine ecotype) and Bothnian Sea (5 psu, brackish ecotype) have been compared with respect to the ability to withstand desiccation at different temperatures (0, 10, and 20°C). The aim was also to investigate the importance of salinity and light for the availably energy reserves, osmotic adjustment, and pigment content. The maximum quantum yield of photosystem II photochemistry (Fv/Fm) values revealed that the marine ecotype was more able to resist desiccation. The brackish algae showed a decrease in Fv/Fm as a response to desiccation at all temperatures, but the decrease was most pronounced at 20°C. The brackish ecotype recovered from desiccation within 5 h only when treated at 0°C. When the two ecotypes were treated at different levels of salinity in darkness and light, the results suggested that both salinity and irradiance are main factors in the differences in mannitol content between the two ecotypes. Chlorophyll (Chl) measurements showed 25% higher Chl α and 60% higher Chl c in the brackish ecotype in comparison to the marine ecotype. Darkness had a more pronounced effect on the Chl content than the salinity and initiated an increase in the amount of Chl, especially Chl c in the brackish ecotype.
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| 4. |
- Borglund, Erik A.M., et al.
(författare)
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How are records used in organizations?
- 2008
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Ingår i: Information research. - 1368-1613. ; 13:2
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Tidskriftsartikel (refereegranskat)abstract
- Introduction. This paper reports an investigation of whether the use made of records affects the design of record keeping systems.Method. The empirical data used in this paper are from four interpretative case studies. A total of fifty interviews and 100 hours of participative observations have been used in data collection. Analysis. The analyses of the collected data have followed a qualitative approach where the data have been categorized and re-categorized. An analysis model was developed based on archival theory and temporal structures, which were the primary purpose and secondary purposes of the use of records. Results. In the temporal structure, the use characteristics were the relationship to a predetermined work process, which required use of records. Within the other temporal structure, the secondary purpose of records use, the use was more difficult to predetermine or identify in advance. The characteristics of the users and their use resulted in unknown users and use of records. Conclusions. It is difficult to predict future use of records, which requires new methods and techniques for design and developing of record keeping systems that can take both the unknown and known user needs into consideration.
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| 5. |
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| 6. |
- Brinza, Loredana, et al.
(författare)
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Cadmium tolerance and adsorption by the marine brown alga Fucus vesiculosus from the Irish Sea and the Bothnian Sea
- 2009
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Ingår i: Bioresource Technology. - : Elsevier BV. - 0960-8524 .- 1873-2976. ; 100:5, s. 1727-1733
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Tidskriftsartikel (refereegranskat)abstract
- Cadmium (Cd) uptake capacities and Cd tolerance of the marine alga Fucus vesiculosus from the Irish Sea (salinity 35 psu) and from the Bothnian Sea (northern Baltic, 5 psu) were quantified. These data were complemented by measurements of changes in maximal photosynthetic rate (Pmax), dark respiration rate and variable fluorescence vs. maximal fluorescence (Fv:Fm). At concentrations between 0.01 and 1 mmol Cd l−1, F. vesiculosus from the Bothnian Sea adsorbed significantly more (about 98%) Cd compared with F. vesiculosus from the Irish Sea. The photosynthetic measurements showed that the Bothnian Sea F. vesiculosus were more sensitive to Cd exposure than the Irish Sea algae. The algae from the Irish Sea showed negative photosynthetic effects only at 1 mmol Cd l−1, which was expressed as a decreased Pmax (−12.3%) and Fv:Fm (−4.6%). On the contrary, the algae from the Bothnian Sea were negatively affected already at Cd concentrations as low at 0.1 mmol Cd l−1. They exhibited increased dark respiration (+11.1%) and decreased Fv:Fm (−13.9%). The results show that F. vesiculosus from the Bothnian Sea may be an efficient sorption substrate for Cd removal from Cd contaminated seawater and this algae type may also have applications for wastewater treatment.
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| 7. |
- Ellis, Gemma L, et al.
(författare)
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Two-Step synthesis of Achiral Dispiro-1,2,4,5-tetraoxanes with outstanding antimalarial activity, low toxicity, and high-stability profiles
- 2008
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Ingår i: Journal of Medicinal Chemistry. - : American Chemical Society (ACS). - 0022-2623 .- 1520-4804. ; 51:7, s. 2170-2177
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Tidskriftsartikel (refereegranskat)abstract
- A rapid, two step synthesis of a range of dispiro-1,2,4,5-tetraoxanes with potent antimalarial activity both in vitro and in vivo has been achieved. These 1,2,4,5-tetraoxanes have been proven to be superior to 1,2,4-trioxolanes in terms of stability and to be superior to trioxane analogues in terms of both stability and activity. Selected analogues have in vitro nanomolar antimalarial activity, good oral activity and are non-toxic in screens for both cytotoxicity and genotoxicity. The synthesis of a fluorescent NBD-tagged tetraoxane probe has allowed investigation into the mechanism of accumulation of these drugs using laser scanning confocal microscopy techniques.
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| 8. |
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| 9. |
- Hellström, Lisbeth Maria, 1969-, et al.
(författare)
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A Study of Fracture processes in Wood Chipping
- 2008
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Ingår i: 6th Fundamental Mechanical Pulp Research Seminar. - Espoo : KCL Oy Keskuslaboratorio - Centrallaboratorium AB.
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Konferensbidrag (refereegranskat)
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