S-layer proteins of S. ureae ATCC 13881 form on the cell surface an S-layer lattice with p4 square type symmetry and a period of about 13.5 nm. These lattices were shown to be the excellent nanotemplates for deposition of regular metal clusters. The synthesis of the S. ureae S-layer protein is highly efficient, the protein accounts for approximately 10-15 % of the total cell protein content, judged by the SDS-PAGE results. Besides, the S-layer protein production is tightly regulated, since only negligible amounts of S-layer proteins are observed in the medium at different cell growth phases. At the same time, mechanisms of the regulation of S-layer protein synthesis are poorly understood. As several hundreds of S-layer proteins are produced per second during the cell growth, the S-layer gene promoters are among the strongest prokaryotic promoters at all. However, little is known about factors regulating the expression of S-layer genes, furthermore, no experimental identification of other upstream regulatory sequences except for -35/-10 and RBS sequences was presented to our knowledge to date. A sequence of the S-layer gene of S. ureae ATCC 13881, encoding the previously described S-layer protein, was identified in this work by combination of different approaches. The largest part of the gene, excluding its upstream regulatory and ORF 5’ regions, was isolated from a genomic library by hybridization. The sequence of the isolated fragment proved to contain additionally an 1.9 kb non-coding region and an incomplete 0.8 kb ORF region in its 3’-part. No RBS sequence and apparent promoter regions could be identified in front of the latter sequence, suggesting that it might represent a pseudogene sequence. The sequences of the 5’ and upstream regions of the S. ureae ATCC 13881 S-layer gene were identified by combination of PCR-sequencing and chromosome walking. Totally, a sequence of the 6.4 kb long region of S. ureae genomic DNA was established. The sequence of the S. ureae S-layer protein was deduced from the respective gene sequence and agreed with the peptide sequences, obtained after N-terminal sequencing of tryptic peptides of the S. ureae ATCC 13881 S-layer protein. For the protein the name SslA was proposed, which is an abbreviation for “Sporosarcina ureae S-layer protein A”. Several specific features were observed in gene organisation of sslA, which are also characteristic for other S-layer genes. The distance between the -35/-10 region and the ATG initiation codon is unusually long and a 41 bp palindromic sequence is present in the immediate vicinity of the -35/-10 region. Besides, a distant location of the rho-independent transcription terminator, which is 647 bp remote from the stop codon, will result in the mRNA transcripts with unusually long trailer region. Both the long 5’ UTR and the long 3’ trailer may have a regulatory function, either by conferring increased mRNA stability and/or by affecting translation efficiency. Potentially these sequences may define the binding sites of regulatory proteins. For example, palindromic sequences constitute the regulatory sites in several bacterial operons and may act as the binding sites of regulatory dimeric proteins. In respect to the conservation of the sslA sequence high similarity to the sequences of other functional S-layer genes, especially the slfA and slfB genes of B. sphaericus, was observed, whereas the results of phylogenetic analysis support the hypothesis that S-layer genes may have evolved via the lateral gene transfer. Based on the sslA sequence, several recombinant proteins with truncations of the terminal protein parts or C-terminal fusion of either EGFP or histidine tags were constructed. For all the truncated or EGFP-fusion SslA derivatives high level overexpression in E. coli was possible. For native SslA a moderate level of expression was observed suggesting that its high intracellular concentration may downregulate the protein synthesis. Interestingly, fluorescence microscopy indicates the same intracellular localization for heterologously produced recombinant proteins with fusions of EGFP either to the precursor or to the native SslA protein, suggesting that SslA secretion signal is not functional in E. coli. Heterologously produced SslA derivatives with truncations of N-, C- or both N- and C-terminal parts were shown to self- assemble in vitro, although the size of self-assembly structures was different from that observed upon the self-assembly of the native SslA. In the latter case extended self-assembly layers with the size up to 5x10 µm were observed, with a surface area of up to two orders of magnitude higher than that of S-layer patches, routinely isolated from S. ureae surface. Dependent on the applied recrystallization conditions preferential formation of single- or multilayer self-assembly structures was observed.

För att världen ska bli mer socialt, ekonomiskt och miljömässigt hållbar till år 2030 skapade FN de globala målen. En omställning till cirkulär ekonomi är nödvändig för att nå de globala målen. Cirkulär ekonomi innebär att resurser används i effektiva cirkulära flöden och ersätter jungfruligt material. Cirkulära flöden kan minska den stora materialkonsumtionen och utsläppen av växthusgaser som byggsektorn och industrisektorn är ansvariga för. Sveriges ekonomi är i dagsläget linjär, där bara cirka 3% av allt material som nationen konsumerar återinförs in i ekonomin. Det finns en stor materialtillgång från industriavfall i urbana områden som i dagsläget kasseras men som fortfarande har ett potentiellt värde att återbrukas. Syftet med studien är att inventera materialflöden i region Norrbotten som är klassade som utdömda av företag och industrier utanför byggsektorn. Studien inriktar sig särskilt på att inventera restmaterial i städerna Luleå, Boden och Piteå och analysera om materialen kan återbrukas som ytskiktsmaterial för fasad och tak på ett miljöhus. Analyserna ska resultera i gestaltningsförslag för de restmaterialen med störst potential till återanvändning för att väcka inspiration för återbruk. Studien undersöker också de vanligaste utmaningarna med återbruk inom byggsektorn. Datainsamlingen har skett genom en litteraturstudie och en inventering av lokala restmaterial. Inventeringen har utförts med hjälp av metoden Harvest Map, semistrukturerade intervjuer och studiebesök. Analysen av restmaterialen har baserats på Ashbys materialvalsmetod. Metoden innebär bestämning av kriterier, uteslutning av material samt rangordning av material. Rangordning av material har genomfört med hjälp av en multikriterieanalys. Enligt Ashbys materialvalsmetod definierades tolv kriterier. Av sju företag som inventerades exkluderades tjugosex av trettiosju restmaterial från studien. Elva restmaterial uppnådde de kriterier som var nödvändiga för att återbruka som ytskiktsmaterial och rangordnades enligt multikriterieanalysen. De tre material som rangordnades högst var rostfri plåt från värmeväxlare, plåt från sandwichelement och gabionvägg av masugnsslagg. Fallscenario för fasad- och takytskikt gestaltades för dessa tre material och som påvisar att det finns goda möjligheter för de inventerade restmaterialen att återbrukas som ytskiktsmaterial. Inventeringen hos de få företag som gjordes visade att det finns en stor materialtillgänglighet i region Norrbotten som har potential att återbrukas. Det framgick också att det finns intressanta materialflöden hos industrier som byggsektorn kan dra nytta av. Återbruk av material kräver samarbete mellan de involverade parterna. Samarbetet innebär bland annat att dela med sig information om tillgängliga resurser i materialflöden, materialens egenskaper och ursprung. Detta är nödvändigt för att underlätta inventeringen av potentiella material att återbruka. Samarbetet kan hindras av företagens och industriernas integritet och konkurrens mellan företagen. En tänkvärd aspekt som upptäcktes under studien var att låta restmaterialen återbrukas till andra funktioner hos byggnaden. Detta i kombination med att utföra en storskalig materialinventering vore intressant för fortsatta studier. / In order for the world to become more socially, economically and environmentally sustainable by the year 2030, the UN created the global goals. A transition to a circular economy is necessary to reach the global goals. Circular economy means that resources are used in efficient circular flows and replace virgin material. Circular flows can reduce the large material consumption and emissions of greenhouse gases that the construction and industrial sectors are responsible for. Sweden's economy is currently linear. Only 3% of all the material that the nation consumes is reintroduced into the economy. There is a large supply of material from industrial waste in urban areas that is currently discarded but still has potential value to be reused. The purpose of the study is to inventory material flows in the Norrbotten region that are classified as condemned by companies and industries outside the construction sector. The study focuses in particular on inventorying residual materials in the cities of Luleå, Boden and Piteå and analyzing whether the materials can be reused as surface layer material for facade and roof of an environmental house. The analysis should result in use case scenarios for the residual materials with the greatest reuse potential to inspire for reuse. The study also examines the most common barriers for reuse in the construction sector. According to Ashby's material selection method, twelve criteria were defined. Of seven companies that were inventoried, twenty-six out of thirty-seven residual materials were excluded from the study. Eleven residual materials fulfilled the criteria necessary for reuse as surface layer material and were ranked according to a multi-criteria decision analysis. The three materials with the highest rank were stainless steel plate from heat exchangers, plate from sandwich elements and gabion wall of blast furnace slag. Use case scenarios for facade and roof surface layers were designed for these three materials. This showed good opportunities for the inventoried residual materials to be reused as surface layer material. The inventory of the few companies that was made showed that there is a large availability of material in the Norrbotten region that has the potential to be reused. The analysis showed that there are interesting material flows in industries that the construction sector can benefit from. Reuse of materials requires cooperation between the parties involved. The collaboration involves, among other things, sharing information on available resources in material flows, the properties and origin of the materials. This is necessary to facilitate the inventory of potential material to reuse. Integrity and competitiveness of companies and industries can affect the cooperation. A conceivable aspect that was discovered during the study was to allow the residual materials to be reused for other functions on the building. This, in combination with carrying out a large-scale material inventory, would be interesting for further studies.

Dans les filtres plantés de roseaux à écoulement vertical, la percolation des eaux usées à travers le milieu filtrant entraine la rétention physique des matières en suspension à la surface des filtres, et leur accumulation conduit à la formation d’une couche de boue principalement sur le premier étage des filtres. Longtemps considérée comme un facteur de risque de colmatage, cette couche de surface est aussi un compartiment majeur de la performance du système. Dans l’objectif de mieux connaitre la nature et l’évolution des dépôts qui la constituent, des échantillons issus de 14 stations en fonctionnement ont été prélevés pour analyser notamment la nature de leur matière organique particulaire et son évolution. Les résultats ont montré que les dépôts de stations de plus de trois ans de fonctionnement tendent vers un état similaire, caractérisé par la présence de composés organiques stables et complexes et par une plus faible réactivité de la matière organique particulaire. Les dépôts provenant de stations de moins d’un an de fonctionnement présentent une signature particulière, caractérisée par une matière organique réactive et peu mature. En complément de cette évolution en surface du filtre, la matière organique particulaire des eaux usées entrantes peut également subir des modifications au sein du process d’un filtre planté de roseaux. La présence d’un lit bactérien comme traitement additionnel participe à l’hydrolyse et à la transformation de la matière organique particulaire par des processus de minéralisation et d’humification. L’ajout de chlorure ferrique favorise l’agrégation de la matière. Enfin, des polluants organiques et métalliques d’intérêt ont fait l’objet d’une première quantification dans ces dépôts afin d’estimer leur rétention pour mieux appréhender les risques potentiels en cas de dysfonctionnement ou d’épandage. L’étude du comportement à la lixiviation en fonction du pH a permis de mettre en évidence que la libération de certains éléments traces est liée à celle de la matière organique. / The percolation of unsettled wastewater in French Vertical Flow Constructed Wetlands (VFCWs) causes the formation of a sludge layer at the surface of the first stage filter due to the retention of sludge deposits. Although the growth of this layer over the years of operation is a potential source of clogging risks, it also largely contributes in the performance of the system, depending on its properties. In order to better understand these phenomena, surface sludge deposits samples taken from 14 VFCW sewage treatment plants were collected and analyzed. Results showed that the structure and composition of the sludge deposits from treatment plants with more than three years of operation time were remarkably similar, characterized by the presence of stable and complex organic compounds and a low reactivity and biodegradability of the particulate organic matter. Deposits from treatment plants with less than one year of operation time were composed of more reactive and less mature organic matter. The particulate organic matter of the inflow wastewater was also shown to undergo modifications within the treatment chain of the vertical flow constructed wetland. The implementation of a biological trickling filter as an additional treatment prior to the filter stages was found to induce the transformation of soluble and particulate organic matter through mineralization and hydrolysis, and to contribute to humification probably by the detachment of biofilm fragments. The injection of ferric chloride used to precipitate phosphates was found to promote aggregation within the sludge deposits. Finally, the role of the sludge layer in the retention of a selection of organic and metallic pollutants in VFCW systems has been evaluated by analyzing sludge deposits samples. Detergents were found at higher concentrations than PCPP. The potential release of the sorbed contaminants was studied using leaching tests as a function of pH. Results showed that the release of some trace metals (mostly copper) was governed by the leaching behavior of organic matter.

The master thesis dealing with problematic about durability of concrete, with use of recycled concrete and addition of silica additions. Predominant for resistance of concrete constructions is surface layer, through which aggressive gasses and liquids penetrate from surrounding environment. The most important indicator of concrete durability is ability of surface layer transmissions of aggressive substants. In experimental part will be defined the actual state of surface layer by normal testing methods. The transmissions of surface layer will be tested on concrete cubes. Tests for transmissions of air (method TORRENT), of water (method ISAT), of acid gases (dept of carbonation by quick test in 98% CO2) will be carried out and also strength tests. Assessment of positive or negative influence of additions and amount of cement on durability and mechanical properties of concrete will be discussed in conclusion.

This master thesis is divided into two parts: theoretical and practical one. In the theoretical part there is described hydraulic roughness, velocity distribution in the case of hydraulically rough surface and the process of grain sorting in surface layer. The practical part of the thesis resolves the influence of surface layer on hydraulic roughness of bed, expressed by Nikuradse sand grain size ks. The results are formulas explaining dependence of ks on characteristic grain size dx from grain-size distribution curve and comparison with coefficient ks according to different authors.