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Dette prosjektet har hatt som mål å integrere, modellere og tilgjengeliggjøre marine grunnkart for Svalbard. Dyp, strøm, saltholdighet, temperatur, ulike terrengforhold (inkl. skråning, bassenger) og områder med skred og usortert sediment har blitt modellert og/eller avgrenset på grov skala (for hele Svalbard), på mellomskala (for utvalgte fjorder) og/eller på fin skala (for Kongsfjorden). Vi har sammenstilt data på tare og sedimentlevende dyr (infauna) og klassifisert hvilke områder i Kongsfjorden som mest sannsynlig egner seg for tarevekst og som potensielt kan ha over gjennomsnittlig høyt antall individer i sedimentene. Good information on coastal marine conditions is essential for management and planning. This project aimed to integrate, model and make available marine base maps for Svalbard. Depth, ocean current speed, salinity, temperature, different terrain types (incl. slope, basins) and areas of avalanches and unsorted sediment have been modelled/delineated at a coarse scale (for the entire Svalbard), at a medium scale (for selected fjords) and/or at a fine scale (for the Kongsfjord). We also integrated point data on kelp and sediment dwelling animals (infauna) and classified for the Kongsfjord in order to find areas most likely suitable for kelp growth and that potentially have an above average number of fauna individuals in the sediments. Svalbards miljøvernfond

Seagrass meadows are highly productive habitats that can act as “blue carbon sinks” in coastal ecosystems by facilitating sedimentation and trapping particles. However, the magnitude and occurrence of these effects may be species and density dependent. The present study is the first estimation of seagrass sediment carbon sink in the temperate Zostera marina beds in the Baltic Sea. Several descriptors of organic matter characteristics, along with possible organic matter sources in the sediment were compared at vegetated and unvegetated bottoms. The 210Pb dating of the sediment has been used for accumulation rate assessment. The photopigments and POC concentrations in sediments were higher in vegetated bottoms. The SIAR (Stable Isotopes in R) mixing model based on nitrogen and carbon stable isotope values, indicated that higher percentages of organic matter originated from seagrass production in vegetated sediments (40–45%) compared to unvegetated ones (5–21%). The carbon stock in the upper 10 cm of the vegetated sediments ranged from 50.2 ± 2.2 to 228.0 ± 11.6 (g m−2), whereas the annual C accumulation amount from 0.84 ± 0.2 to 3.85 ± 1.2 (g m−2 yr−1). Our study shows that even the relatively weakly developed vegetation of the small temperate seagrass species enhance organic carbon concentration in the sediments. Estimated carbon stock was much lower than those reported for most of the seagrass meadows elsewhere, and the carbon burial rate was the lowest ever reported. Evidently, the global calculations of sediment carbon stock should be reconsidered by taking into account density and species-related variability.

Publisher Summary Size-exclusion chromatography (SEC), also called “gel-permeation chromatography,” “molecular-sieve chromatography,” or “gel filtration,” separates molecules according to their sizes. Smaller molecules are retarded on a column, whereas larger ones are eluted more rapidly. As the retention time can be directly correlated with the sizes of molecules, this method is particularly useful for the determination of molecular weight. SEC is generally applicable to the separation of molecules in the range of 0.5–1000 kDa, but larger proteins or other giant molecules can also be separated. SEC can also physically separate folded macromolecules from the unfolded ones, particularly in the case of slow equilibria. The major applications of SEC include the determination of molecular weight and molecular-weight distribution of natural and synthetic polymers. Separation strongly depends on many factors such as column packing, column dimensions, flow rate, sample volume, and mobile-phase composition. Capillary SEC provides a separation strategy for microscale purification. Capillary SEC columns are best suited for direct coupling to electrospray ionization–mass spectrometry (ESI–MS) because they have comparable flow rates that can be delivered to the ESI source without splitting.

The coding sequence in DNA molecule is considered as a message to be transferred to receiver, the proteins, through a noisy information channel and each nucleotide is assigned a respective information weight. With the help of the nucleotide substitution matrix we estimated the lower bound of the amount of information carried out by nucleotides which is not subject of mutations. We used the calculated weights to reconstruct k-oligomers of genes from the Borrelia burgdorferi genome. We showed, that to this aim there is sufficient a simple rule, that the number of bits of the carried information cannot exceed some threshold value. The method introduced by us is general and applies to every genome., Comment: 8 pages, 7 figures, submitted for publication

A new model for the bivariate distribution of chain sizes and composition in copolymers is presented. The model combines the sum of a two-bivariate distribution, and it replaces the previous model that consists of a single entity. The compositional distribution histogram was obtained by summation of the sections of the bivariate distribution that belong to a narrow compositional range. The predictions of the model were compared with mass spectrometric data relative to a block copolymer sample containing structural units of pivalolactone and 3-hydroxybutyrate with some literature data, namely, mass spectrometric data concerning a random copolymer sample reacted at high conversion containing units of styrene and methyl methacrylate as well as a block copolymer sample containing units of -methyl styrene and methyl methacrylate. The new model gives better results than the previous model because it fits better with the experimental compositional distribution histogram of the copolymer samples.

A new model for the bivariate distribution of chain sizes and composition in copolymers is presented. The model combines the sum of a two-bivariate distribution, and it replaces the previous model that consists of a single entity. The compositional distribution histogram was obtained by summation of the sections of the bivariate distribution that belong to a narrow compositional range. The predictions of the model were compared with mass spectrometric data relative to a block copolymer sample containing structural units of pivalolactone and 3-hydroxybutyrate with some literature data, namely, mass spectrometric data concerning a random copolymer sample reacted at high conversion containing units of styrene and methyl methacrylate as well as a block copolymer sample containing units of a-methyl styrene and methyl methacrylate. The new model gives better results than the previous model because it fits better with the experimental compositional distribution histogram of the copolymer samples. (C) 2002

Synthesis of an a,beta-alkyl branched polyester, i.e., poly(2-methyl-3-hydroxyoctanoate), has been accomplished via anionic polymerization of alpha-methyl-beta-pentyl-beta-propiolactone mediated by supramolecular complexes of potassium methoxide or potassium hydroxide, respectively. The structure of resulting polymers has been established by electrospray ionization multistage mass spectrometry (ESI-MSn), FT-IR, NMR, and GPC analyses. Previously proposed addition-elimination mechanism of the polymerization of beta-lactones containing alpha-hydrogen by alkoxide anion has been confirmed to operate also in the case of beta-lactone having alkyl substituents in both alpha and beta positions.

Sequence distribution and chemical structure of mass-selected macromolecules of poly(3-hydroxybutyrate-co-3-hydroxyvalerate), PHBV, biopolyester macroinitiator obtained by partial alkaline depolymerization of natural PHBV containing 5 mol % of HV units was determined by electrospray ionization multistage mass spectrometry (ESI-MSn). On the basis of the ESI-MSn studies of PHBV individual;oligomers, the microstructure of this bacterial copolyester was assessed, starting from dimer up to the oligomer containing 22 repeat units, and the results obtained were compared with those described previously for other "soft" ionization MS techniques.