This thesis is a summary of five papers concerning endocyclic cleavage of glycosides and related acetals. Simple lactol ethers undergo endocyclic cleavage to give acyclic chain extended products on treatment with organoaluminium and organotitanium reagents. The first examples where organotitanium reagents induced alkylative endocyclic cleavage of carbohydrates is presented. The best conditions for

This thesis treats some information-theoretical and coding aspects of communication over multiple-access and fading channels. It consists of a general introduction and seven papers. In code-division multiple-access (CDMA) communication, many users have access to the channel simultaneously. Since the users interfere with one another, error correcting coding is necessary in order to obtain good per

Popular Abstract in Swedish Alla flercelliga organismer är uppbyggda av celler. Cellen omges av ett plasmamembran, som innesluter cellens vätska (cytosol) i vilken finns små organeller. Varje organell har sin uppgift i cellen, som t.ex. kärnan innehåller genetiskt material (DNA) och mitokondrier producerar energi i form av ATP. Många uppbyggnadsprocesser som sker i celler t.ex. proteinsyntes kräveIn addition to complex I, the plant mitochondrial electron transport chain possesses several alternative NAD(P)H dehydrogenases, not present in animals. These enzymes allow nonenergy-conserving electron transfer from cytoplasmic and matrix NAD(P)H to ubiquinone. The mitochondrial inner membrane was permeabilised with a channel-forming antibiotic, alamethicin, and the activity of internal NADH deh

Abstract in Undetermined This report presents a security evaluation of the Enocoro-128v2 stream cipher. Enocoro-128v2 was proposed in 2010 and is a member of the Enocoro family of stream ciphers. This evaluation examines several different attacks applied to the Enocoro-128v2 design. No attack better than exhaustive key search has been found.

An improved nonlinear asymptotic theory of spiral density waves is developed. It extends the theory developed by Yuan & Kuo to a global theory, not just one limited to the vicinity of the resonance. It can then be applied to the recent high-resolution observations of CO and HST NICMOS of nearby spiral galaxies. As an example, we apply the theory to the nearby grand-design spiral galaxy NGC 524

Cationic polymers in the form of anion-exchange membranes (AEMs) may enable a route towards low platinum or even platinum-free alkaline membrane fuel cells with the potential to oxidize more complex fuels than hydrogen and methanol [1-4]. The main challenges for the AEMs are currently to enhance the alkaline stability of the cationic group and to improve the ion conductivity. In this context, ther