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Popular Abstract in Swedish Kryptering kan användas när man vill hålla något viktigt meddelande hemligt, till exempel vid en bankbetalning på Internet. Men hur vet man att krypteringsalgoritmen (sättet att kryptera på) är tillräckligt säker? Hur vet man att ingen kan läsa vårt meddelande eller ändra i det så att, till exempel, en överföring av pengar från ett konto till ett annat går till någon heThe aim of this dissertation is to show some cryptanalytical results on a selection of stream ciphers. We have grouped theory and results into three main parts. The first part focuses on the FCSR-based constructions X-FCSR and F-FCSR-H v3. For the X-FCSR family of stream ciphers we perform a severe state recovery attack. This attack works for both X-FCSR-128 and X-FCSR-256. We then develop a gen

Near vacuum ultraviolet (UV) upconversion (UC) emissions with a spectral resolution of 1 nm, from the (6)G(J), D-6(J), I-6(J), P-6(J) levels of Gd3+ and the L-2(17/2), D-4(7/2), H-2(2)(9/2), D-2(5/2), (4)G(7/2), K-2(13/2), P-2(3/2) levels of Er3+, were observed under 974 nm laser excitation. Mechanism analyses illustrate that successive energy transfers (ETs) from Yb3+ to Er3+ generate UV UC radia

A dynamic mathematical model for simulating the coupled heat and moisture migration through multilayer porous building materials was proposed. Vapor content and temperature were chosen as the principal driving potentials. The discretization of the governing equations was done by the finite difference approach. A new experimental set-up was also developed in this study. The evolution of transient t

The role of informal venture capital in entrepreneurial process and economic development is increasingly recognized by scholars and policy-makers around the world. Much of the attention that this form of financing has received during the last couple of decades is due to its potential to bridge the regional equity gap. This study is concerned with regional distribution of informal venture capital a

Ingvar Kärnefelt hittade i somras den ovanliga lundgamandern på en till synes naturlig lokal i mellersta Halland.

Det område som idag kallas Strövområdet Arriesjön har bytt skepnad flera gånger under de senaste tre hundra åren. De processer och den historia som åstadkommit dessa förändringar speglas i de två historiska kapitlen. Men i det här kapitlet ger vi en översikt över områdets rent fysiska förändringar med hjälp av de flesta kartor och flygfoton som finns tillgängliga, från den första kartbilden 1702 t

Many bird species migrate long distances without any food intake and must optimize storage of energy with respect to minimization of aerodynamic drag. To contribute to the understanding of this issue, we investigated, by magnetic resonance imaging (MRI), spatial distributions of body fat during the accumulation process before migration. We collected data from 12 Lesser Whitethroats (Sylvia curruca

BACKGROUND: Post-partum hemorrhage (PPH) is the major cause of maternal mortality in Ghana and worldwide. Active management of the third stage of labor (AMTSL) is a globally recommended three-step method that in clinical trials has been proven effective in prevention of PPH. The AMTSL guidelines were introduced in 2003, modified in 2006, and has been part of the national guidelines in Ghana since

Streptococcus agalactiae and Streptococcus pyogenes are two related human pathogens causing different diseases. This thesis focuses on a number of surface proteins expressed by S. agalactiae and S. pyogenes and, more specifically, the molecular and biological characterization of these proteins. The first paper describes the novel Blr protein of S. agalactiae, which together with the previously de

The MAX IV storage rings, currently under construction in Lund, Sweden, will use third harmonic cavities operated passively to lengthen the bunches and alleviate collective instabilities. These cavities are an essential ingredient in the MAX IV design concept and are required for achieving the final design goals in terms of stored current, beam emittance, and beam lifetime-such performance challen

Depression and bipolar disorder, collectively known as mood disorders, are devastating, common and often chronic illnesses. Imaging studies of patients with mood disorders have demonstrated structural changes in several brain regions implicated in mood regulation. Furthermore, bipolar disorder is associated with white matter abnormalities and post mortem analysis of brain tissue from patients with

The rise of MEMS and µTAS techniques has created a whole new family of microfluidic devices for a wide range of chemical and biomedical analyses to be performed on small Lab-on-a-chip platforms. The operations often include small samples of particle or cell suspensions on which separation, mixing, trapping or sorting is performed. External fields and forces are used for these operations, and this

Extreme climatic events such as the El Nino Southern Oscillation profoundly affect many plants and animals, including amphibians, which are strongly negatively affected by drought conditions. How amphibians respond to exceptionally high precipitation as observed in La Nina events, however, remains unclear. We document the correlation between the exceedingly wet 2010-2012 La Nina and community-leve

In this work the sensitivity-increasing effect of single-walled carbon nanotubes (SWCNTs) in amperometric biosensors, depending on their average length distribution, was studied. For this purpose the SWCNTs were oxidatively shortened and subsequently length separated by size exclusion chromatography. Transmission electron micrographs of different fractions of SWCNTs were collected. Diaphorase "wir

Laminar burning velocity of lean hydrogen + air flames at standard conditions is still a debated topic in combustion. The existing burning velocity measurements possess a large spread due to the use of different measurement techniques and data processing approaches. The biggest uncertainty factor in these measurements comes from the necessity to perform extrapolation to the flat flame conditions,

Background: Thrombolysis is a common method in the treatment of lower extremity bypass graft occlusion. The purpose of this study was to investigate the results of thrombolytic therapy in the management of acute bypass graft occlusion and to identify risk factors for technical failure and amputation. Methods: All patients at two tertiary referral centers undergoing thrombolysis for acute graft occ