<p> The nitrogen and hydrogen-deuterium isotope effects have been measured for the base-promoted elimination reactions of cis-and trans-2-phenylcyclopentyltrimethylammonium ions and cis-and trans-2-phenylcyclohexyltrimethylammonium ions. The observations have been interpr eted as indicative of a concerted E2 mechanism for both trans and cis elimination processes. In the cis eliminations, however, proton transfer to base is far advanced at the transition state resulting in a much higher degree of carbanionic character ass ociated with the transition state than for the trans eliminations. </p> <p> The kinetic isotope effect results for these cyclic systems establish that the two bond-rupture processes complement each other; the greater the extent of proton transfer to base at the transition state, the smaller is the extent of C-N bond weakening. These observations are interpreted in terms of the coupling of the motion which extends the lengths of the H-C and C-N bonds at the transition state and the approach to coplanarity of the bonds involved in the elimination process. </p> / Thesis / Doctor of Philosophy (PhD)

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This study examines the efficiency of ion cyclotronresonance heating in multi-ion plasmas in JET (Joint EuropeanTorus), using deuterium and tritium as fuel along with smallconcentrations of a third ion species. In particular, two ionminority scenarios, hydrogen and helium, as well as a 3-ionscenario using beryllium were constructed. The scenarios weresimulated with FEMIC and the obtained data was then compiledand analyzed through a number of metrics.The highest total power absorption was 8.56 W and wasachieved by the 4% hydrogen scenario. However, 8% hydrogenattained the highest power partition by the minority ion species.The optimal beryllium concentration regarding absorbed powerwas 0.1% in 36.2% deuterium and 63.4% tritium, with a totalcoupled power of 6.94 W. The highest power partition byberyllium was noted for the 0.25% case in a 36% deuteriumand 63% tritium plasma. / Denna studie undersöker effektiviteten av joncyklotronresonansuppvärmning av JETs (Joint European Torus) plasma, med deuterium och tritium som bränsle, samt små koncentrationer av ett tredje ämne. Mer specifikt undersöks två scenarier med minoritetsjoner, helium och väte, och ett 3-jonscenario med beryllium. För att undersöka dessa olika konstellationer körs simuleringar i FEMIC. Datan som fås från simuleringarna sammanställs och analyseras i enlighet med olika mått. Den högsta totala absorptionen av energi var 8.56 W och fas av 4% väteminoritet. 8% väte ger den högsta energipartitionen för det tredje jonslaget. Beryllium absorberade som mest 6.94 W, detta med 0.1% beryllium, 36.2% deuterium och 63.4% tritium. Den högsta energipartitionen för beryllium uppnåddes med 0.25% beryllium, 36% deuterium och 63% tritium. / Kandidatexjobb i elektroteknik 2020, KTH, Stockholm

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- 5 - Abstract Hydrogen/deuterium exchange coupled to mass spectrometry (HX-MS) utilizes the spontaneous exchange of protein backbone amide hydrogens for deuterium atoms from solution to gain information about changes in protein structure. To localize these changes to specific areas of the protein, enzymatic digestion by aspartate proteases is used. The proteases' ability to produce small overlapping peptides and to provide full sequence coverage of the studied protein is essential for pinpointing the protein regions of interest. In this study recombinant proteases nepenthesin I (Nepenthes gracilis) and rhizopuspepsin (Rhizopus chinensis) were prepared and compared to commercially available proteases porcine pepsin A and aspergillopepsin (Aspergillus saitoi). The comparison was performed using various activity assays, where the effects of pH, temperature and denaturing and reducing agents on the activity of the proteases were studied. All four proteases were also immobilized on a polymeric resin POROS and their activity in an online HX-MS digestion setup was tested using myoglobin as a model substrate.

Intracellular transport is provided by two major types of molecular motors kinesins and cytoplasmic dynein. Kinesin-1 is a molecular motor that transports molecules and organelles along microtubule tracks anterogradely. Specific protein-protein interactions are required to activate kinesin-1 as the free kinesin exist in an autoinhibited state. The activation of kinesin-1 induces its conformational change, enables microtubule binding and ATP hydrolysis necessary for the directional cargo transport. HDAC6 is a multifunctional protein composed of several domains. It plays an important role in many microtubule dependent processes as HDAC6 is a major tubulin deacetylase. It has been shown that HDAC6 manipulation (inhibition/genetic ablation) affects transport along microtubules but the exact mechanisms are unknown. The effect can be caused either by deacetylation microtubules or direct interaction with molecular motors. This thesis is focused on characterization of interactions between kinesin-1 and HDAC6 that have not been described so far. To this end, we expressed and purified various constructs of kinesin-1 and HDAC6 and tested their interactions by microscale thermophoresis (MST) and hydrogen deuterium exchange (HDX) to determine affinity and interaction sites, respectively. MST data revealed that...

Apostando na versatilidade de nanopartículas bimetálicas como catalisadores em reações orgânicas, nós desenvolvemos um estudo onde nanopartículas bimetálicas de AgAu, AgPd e AgPt, foram utilizadas como catalisadores em reações de oxidação de compostos de silício (1a-j) ao respectivo silanol (2a-j). Empregando a água como agente oxidante, para estas reações, conversões de 43->99% foram alcançadas. Visando formar catalisadores metalo-enzimáticos (CME), nanopartículas bimetálicas de AgAu, AgPd e AgPt foram utilizadas como suporte da CAL-B (CMEs: CALB-AgAu; CALB-AgPd; CALB-AdPt). Esses catalisadores apresentaram dupla atividade catalítica. Foram alcançadas a oxidação do dimetil(fenil)silano (1a), com uma conversão de até 85% e acetilação enantiosseletiva do (R,S)-1-(fenil)etanol (4a) com acetato de vinila, com uma conversão de até 26% e seletividade >99% para formação do (R)-1- fenil(etil)acetato. Nanopartículas bimetálicas de AgPd (NSsAgPd), também foram aplicadas como catalisadores para a hidrogenação de compostos orgânicos utilizando como fonte de hidrogênio compostos de silício. Neste caso treze diferentes substratos foram empregados (5a-5o) (cetonas &#945,¨&#946;-insaturadas, acrilatos, azidas, compostos nitro e iminas) e conversões >99% foram alcançadas para alguns dos produtos reduzidos. Utilizando este mesmo sistema, a incorporação de átomos de deutério em compostos orgânicos foi realizada pela substituição da água por D2O, o que levou à formação de HD/D2. Com esta metodologia conseguimos encorporar o átomo de deutério numa taxa >60% nos compostos 5a e 5m. As NSsAgPd também foram imobilizadas em partículas de sílica para a formação de SiO2-AgPd. Estes catalisadores foram confinados em um reator e utilizados em reações de hidrogenação, sob7 condições de fluxo contínuo, de compostos orgânicos utilizando como fonte de hidrogênio compostos de silício. Sob estas condições conversões de até 92% foram alcançadas para o produto reduzido / We have developed a study where bimetallic nanoparticles of AgAu, AgPd and AgPt were used as catalysts in the oxidation reactions of silicon compounds (1a-j) to the respective silanol (2a-j). Using the water as the oxidizing agent, for these reactions, conversions of 43-> 99% were achieved. In order to form metallo-enzymatic catalysts (MEC), bimetallic nanoparticles of AgAu, AgPd and AgPt were used as support of CALB (CMEs: CALB-AgAu; CALB-AgPd; CALB-AdPt). These catalysts had dual catalytic activity. Oxidation of dimethyl (phenyl) silane (1a) with a conversion of up to 85% and enantioselective acetylation of (R,S)-1-(phenyl)ethanol (4a) with vinyl acetate was achieved with a conversion of up to 26% and selectivity >99% for (R)-1-phenyl (ethyl) acetate formation. AgPd bimetallic nanoparticles (NSsAgPd) were also applied as catalysts for the hydrogenation of organic compounds using silicon compounds as the Hydrogen source. In this case thirteen different substrates (5a-5o) were employed (&#945;,&#946;-unsaturated ketones, acrylates, azides, nitro compounds and imines) and conversions >99% were achieved for several reduced products. Using this same system, the incorporation of deuterium atoms into organic compounds was performed by replacing the water with D2O, which led to the formation of HD/D2. With this methodology we were able to incorporate the deuterium atom in a rate >60% in compounds 5a and 5m. NSsAgPd were also immobilized on silica particles to form SiO2-AgPd. These catalysts were confined in a reactor and used in the hydrogenation reactions under continuous flow conditions of organic compounds using silicon compounds as the hydrogen source. Under these conditions conversions of up to 92% were achieved for the reduced product.