No description available.

No description available.

No description available.

Sewage sludge is an inevitable by-product from waste water treatment plants. Sludgemanagement is a difficult task since sludge has a high moisture content, poordewaterability and generally contain heavy metals, pharmaceutical residues,polyfluorinated alkyl substances (PFAS) and organic pollutants. Recentlyhydrothermal carbonization (HTC) has been getting attention for its suitability to treatsewage sludge. HTC is a flexible process which can handle feedstocks with highmoisture content. The process stabilizes the organic content in a solid residue calledhydrochar which has an increased energy content and decreased moisture contentcompared to the starting material. Hydrochar can be used as soil amendment materialsince it has a good nutrient content and can prevent leaching of fertilizers. However,there is a concern for the risk of high levels of poly aromatic hydrocarbons (PAHs) inthe hydrochar which might limit its applicability in soil applications. PAHs are acomplex group of organic pollutants that can be toxic and even cancerogenic tohumans. 16 PAHs have been described as priority pollutants by the US EnvironmentalProtection Agency due to their toxicity and risk for human exposure. In this studyHTC was performed, with municipal sewage sludge as feedstock, at different processconditions to investigate its influence on the PAH content in the produced hydrocharsand aqueous residues. Ten experiments were performed with varying reactiontemperature (ranging from 180 °C to 260 °C fixed at 1 h residence time) and varyingresidence time (ranging from 1 h to 5 h fixed at 200 °C and 260 °C). The PAH contentof the products was analysed using GC/MS. The hydrochars suitability for soil amendment was investigated. At a 1.7wt.%amendment level (approximately 60 tons/hectare) the results showed that the PAHcontribution from the hydrochars to the soil was well below the SwedishEnvironmental Protection Agency (SEPA) contamination guidelines. No significantPAH content in the products, that might limit the hydrochars applicability for landusages, was observed. The content of the 16 priority PAHs (PAH 16) in thehydrochars were below the international biochar (IBI) limit (6mg/kg TS) and theEuropean Biochar Certificate (EBC) EBC-Agro limit (6mg/kg TS). The PAH contentof the filtrates where below the Swedish Petroleum institute (SPI) irrigationguidelines, except for the filtrate produced at 260 °C, 5 h. In the raw material no PAHspecies was found, however, the reporting limit was higher compared to thehydrochars. Overall, the content of PAH was lower in the filtrates compared to thehydrochar, e.g. at 200 °C, 1 h the content PAH M were 0.05 and 0.85 mg/kg sludgeTS for the filtrate and hydrochar respectively. This was expected since PAHsgenerally has a low solubility in water. To assess the toxicity of the hydrochars thetoxic equivalent quantity (TEQ) was used. The TEQ for the hydrochars wereapproximately ~0.0 to 0.68 mg/kg TS which is below the IBI limit level at 3.0 mg/kgTS. Temperatures around 200 °C to 220° C were found to be favourable in terms ofPAH content in the hydrochar, at 220 °C and 1 h the sum of PAH16 is lower than forall other samples, for both the hydrochar and the filtrate (<R.L and 0.01mg/kg sludgeTS for the hydrochar and filtrate respectively). No significant correlation betweenresidence time and PAH content was observed, except at 260 °C where the PAH16content increased significantly in the filtrates between 1 h and 5 h residence time(0.05 to 0.85 mg/kg sludge TS). In conclusion, HTC was found to be a promisingprocess for utilizing sewage sludge and the results indicates that the risk of high levelsof PAH content of the hydrochars are relatively low.

Microfibrillated cellulose (MFC) films have gained a lot of industrial interest lately dueto their good barrier properties and good mechanical strength. In this study it wasinvestigated whether rheological characteristics and conductivity of MFC dispersionscomprised of different MFC grades could be correlated to tensile properties of the MFCfilms produced from the corresponding MFC dispersion. A rheological characterizationmethod was developed for MFC dispersions with 3 wt% MFC and a secret additiveusing a dynamic rotational rheometer and a smooth “plate to plate” geometry. Themethod consisted of an amplitude sweep, a frequency sweep, and a controlled shearrate measurement. Two predicting OPLS models were created in SIMCA: model 1correlated values from rheological measurements and ionic conductivity to tensileproperties and model 2 correlated MFC grades to tensile properties. A slight correlationbetween MFC rheology and tensile properties could be observed, but due to the lowpredictive ability of model 1 (Q2=0.47) it was deemed that the model was insufficientas a tool for facilitated predictions of new samples. It was concluded that tensileproperties are more correlated to the composition of MFC dispersions than whatrheological characteristics and ionic conductivity the dispersions display, based on thegood predictive ability of model 2 (Q2=0.59).

The pulp and paper industry make up a large part of the Swedish industry and is alsogrowing worldwide. With its growth, the amounts of residuals that are produced alsoincrease. The estimated annual global amount of residuals generated from pulp millsexceeds 1 million tons. The residuals include fly ash (FA) and green liquor dregs(GLD), which can cause harm to the environment as well as to the human health ifnot taken care of properly. Therefore, new, sustainable uses for these residual streamsare in strong need to be found. The construction sector is one of the most energy-intensive and CO2-emitting sectorssince ordinary Portland cement (OPC) is one of the most manufactured materials inthe world and causes large amounts of CO2 emissions when produced. Research hasfocused on reducing the CO2 generated by OPC. One approach is to include FA andGLD in a so-called geopolymer, which is a cementitious material formed when aninorganic material rich in aluminium (Al) and silicon (Si) reacts with an alkalineactivator such as sodium hydroxide (NaOH). A strong geopolymer including FA andGLD would not only create a use for these residuals, but it would also be a lessenergy craving alternative to concrete. Using FA and GLD from the Metsä Board pulp mill in Husum in various proportions,this study aimed for creating a geopolymer that is suitable as a construction material.The composition of the geopolymer blends differed depending on the proportions ofGLD and FA added, as well as regarding the water contents of the blends, and thequantity of alkaline activator solution added. The compositions also varied regardingthe addition of kaolin, an additional aluminosilicate source. Lignosulfonate, a ligninbasedproduct from the sulfite pulping industry was also evaluated as an additive dueto its water-reducing properties when used in concrete. The geopolymers wereevaluated in terms of blend workability and by uniaxial compressive strength (UCS)tests after 7 and 28 days of curing. The strongest geopolymer, in which GLD constituted 20 wt.% of the dry components(sand and alkaline chemicals excluded), endured a pressure of 2.3 MPa after 28 daysof curing. Increasing the water content made the geopolymer blend more workable,but also resulted in a UCS decrease of the geopolymer. Addition of cement to themixture and an increased quantity of alkaline activator solution both resulted in alower UCS as well. Compared to cement mortar (20 MPa at the 7th curing day) andliterature values of other geopolymers, the strengths of the manufacturedgeopolymers were low overall (0.4–1.4 MPa at the 7th curing day). One reason for thelow UCS could be the use of kaolin instead of a more reactive aluminosilicate source.Moreover, the FA showed to have low Si and Al contents, which can affect thegeopolymer strength. Further investigations are needed to develop a strongergeopolymer.

Microfibrillated cellulose (MFC) is a renewable, cellulosic material mainly producedfrom wood fibers, which are found in the secondary cell walls of plant cells. With theincreased demand for renewable biopolymer films in packaging, MFC has emerged asa potential alternative to non-renewable polymer films. However, some obstacles forachieving a highly ductile material that also possesses sufficient barrier propertiesremain. Bacterial cellulose (BC) is a source of nanocellulose that has been reported tohave higher purity, higher flexibility, and better water-absorption capacity and tensilestrength than plant-derived cellulose. One source of BC is from the production ofKombucha, where BC is produced by acetic acid bacteria in a "Symbiotic Culture OfBacteria and Yeast", generally referred to as SCOBY. During SCOBY fermentation, amulti-layered biofilm will form on the air-medium interface. The film consists ofmicrofibrillated bacterial cellulose of high purity and mechanical strength. In thisstudy, the objective was to find out how mechanical properties of a film made ofmicrofibrillated cellulose can be improved by learnings obtained from investigatingthe properties and composition of a film made from SCOBY cellulose. Characterization of the intrinsic properties of washed and unwashed SCOBY wasperformed by using field emission scanning electron microscopy (FE-SEM), Fouriertransforminfra-red (FTIR) spectroscopy, and moisture uptake analysis. Gaschromatography - mass spectrometry (GC-MS) was utilized to examine the presenceof potential plasticizing compounds from the fermentation. Uniaxial tensile testingwas performed on MFC films plasticized with discovered fermentation products toanalyze their impact on the mechanical properties of MFC, such as strain-at-break andE modulus. Additionally, to evaluate how washed and unwashed BC from SCOBYpotentially could be incorporated into MFC films to improve ductility, a study on theeffect of fluidization was performed. The characterization confirmed the high purity of washed SCOBY and the high waterabsorptioncapacity of unwashed SCOBY. GC-MS of dry SCOBY revealed thepresence of hydrophilic compounds from the fermentation with potential to act as biobasedplasticizing agents in SCOBY cellulose. Glycerol and another compound foundin dry SCOBY were tested for their plasticizing properties in MFC films. Glycerolwas found to increase the strain-at-break for MFC films with 181%. The other studiedcompound also improved the ductility of the MFC material. Thereby, a newapplication of this compound was discovered. From the fluidization study, uniaxialtensile testing revealed a strain-at-break of (10.5 ± 0.4) % and E modulus of (10500 ±1140) MPa for MFC films containing 10% washed SCOBY material. Thiscorresponds to an increase in strain-at-break of 402% compared to pure MFC films(2.09 ± 0.42), successfully improving the ductility. The results from this study areplanned to be used as a basis for further studies in the area of bio-based packaging.

No description available.

Membrane proteins make up approximately a third of all proteins and serve as prime drug targets, yet their structural and biophysical characterization presents some unique challenges due to their hydrophobic surfaces and flexible structure. The main goal of this project was to compare, with the use of activity assays, two methods employed for the experimental handling of membrane proteins. The methods compared were the traditional method of using detergent micelles to keep the membrane proteins in solution, with the novel technique of reconstituting the proteins in nanodisks, using the LMCA1 P-type ATPase as a prototype. The secondary goal was to successfully express, purify and reconstitute in nanodisks, an inactive mutant of the LMCA1 protein to use as a control for the activity measurements. As of the end of this project the inactive LMCA1 mutant was successfully reconstituted into MSP1D1 nanodisks and the initial assay results showed higher activity for the reconstituted protein. This points to the conclusion that nanodisks could provide an environment that is more native for the protein, compared to detergent micelles, which can lead to greater precision in their structural and biophysical characterization.

Metacaspases are a recently discovered family of cysteine-dependent proteases present in plants, fungi, and lower eukaryotes. They are believed to be involved in regulated cell death in non-metazoan cells, but little is known about their distinct functional properties. Metacaspases have been identified in various forms of protozoa that cause pathogen-induced diseases, which affect millions of people every year. Their biological function in protozoa and their absence in the human host make them an attractive drug target for treatment of such diseases. In this project, we have explored a potential hit towards metacaspase 4 in Arabidopsis Thaliana. The hit compound was successfully identified from high throughput screening, and an initial structure-activity relationship was established by testing a set of synthesized analogues towards the enzyme. The compounds were also tested against metacaspase 9 in Arabidopsis thaliana, where no inhibitory activity was observed. The active site is highly conserved between the different clades of metacaspases, and these results suggest that the hit compound interacts with an allosteric site on the target.   The results presented here provide important information on how selective regulation of metacaspases can be achieved by developing small chemical probes, targeting allosteric sites on the enzyme. Hopefully, this can be applied to other metacaspases systems to evaluate their biological function in protozoa.