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Mechanisms of Ischemic Brain Injury- studies in murine hippocampal slice cultures

Popular Abstract in Swedish Stroke och hjärtstopp innebär ett minskat eller obefintligt blodflöde (ischemi) till hjärnans celler. Dessa celler är speciellt känliga för ischemi och om blodtflödet är lågt under en längre period leder det till obotliga hjärnskador. Varje år drabbas ungefär 50 000 personer i Sverige av hjärnischemi, vilket gör tillståndet till ett av de vanligaste orsakerna till handiCerebral ischemia is a major cause of mortality and morbidity in the western world. Even though much effort has been put into research and development of effective drugs against ischemic damage there is to date no effective pharmacological brain protective treatment. In order to study particular molecular mechanisms, isolated cellular events and the contribution of individual factors in ischemic d

Synthesis of Non-Natural Aromatic Amino Acids Derivatives Solvent-free reactions-Versatile building blocks-Galectin inhibitors

This thesis deals with three topics concerning the synthesis of non-natural also known as unnatural amino acid derivatives. In the first, solvent-free reaction conditions for the Heck reaction were developed that were superior to previous conditions because the reaction time could be reduced and the work-up procedure simplified. Appropriately substituted, unnatural amino acid derivatives, synthesi

Microbial production of 3-hydroxypropionic acid and poly(3-hydroxypropionate): Investigation of Lactobacillus reuteri propanediol utilization pathway enzymes

Popular Abstract in English Since the onset of the 20th century, human society has been using non-renewable resources, mainly oil, for the production of fuels and chemicals that are now an integral part of our everyday life. In the last few decades however, concerns regarding environmental effects, geopolitical issues and the eventual depletion of oil have led to us re-evaluating our dependency onConcerns regarding environmental issues such as greenhouse gas emissions and climate change have led to a shift within the research community and chemical and energy industry sectors for finding sustainable routes for producing fuels and chemicals from renewable resources, thereby minimizing our dependence on petroleum. The C3-chemical 3-hydroxypropionic acid has been identifed as a top candidate

Classification of Electrocardiographic P-wave Morphology

The atrial activity of the human heart is normally visible in the ECG as a P-wave. In patients with intermittent atrial fibrilation, a different P-wave morphology can sometimes be seen, indicating atrial conduction defects. The purpose of this study was to develop a method to discriminate between such P-waves and normal ones. 20 recordings of each type were used in a classification which, based on

Learning to type with the tip of the tongue : a performance study for a tongue-computer interface

This study is motivated by the need to know the characteristics of the learning processes in tongue-computer interaction and to obtain a useful insight to a better design of the tongue-computer interface for computer text input. Tongue-typing can be a good alternative to hand input methods for physically disabled individuals or tasks where hand-typing is not possible. In order to evaluate the proc

Estimating Error-Probability and Its Application for Optimizing Roll-back Recovery with Checkpointing

The probability for errors to occur in electronic systems is not known in advance, but depends on many factors including influence from the environment where the system operates. In this paper, it is demonstrated that inaccurate estimates of the error probability lead to loss of performance in a well known fault tolerance technique, Roll-back Recovery with checkpointing (RRC). To regain the lost p

Balanced Model Reduction of Linear Time-Varying Systems

This paper treats model reduction of linear time-varying models in continuous time. The method proposed is based on time-varying Lyapunov inequalities and balancing of Gramians. An error bound for truncated models that generalizes the well-known 'twice-the-sum-of-the-tail'-formula for time-invariant balanced systems is obtained. Input-output stability of truncated balanced models is also proved.

L-Band 180 degree passive phase shifter employing auto-tranformer in an SOS process

In this paper, we present a new topology to implement a passive 180° phase shifter using on-chip auto-transformer in an SOS process. The measured results indicate a phase variation of less than 2° over the frequency range of 1.8-2.4GHz. An insertion loss of 2.3dB was measured at 2.1GHz. The phase shifter has a small footprint of 0.3 × 0.7mm2, which is almost three times less than a traditional hig

Investigation of Modified Cellulose and Starch via Hydrolysis and Mass Spectrometry

Popular Abstract in Swedish Stärkelse och cellulosa är naturligt förekommande polymerer av glukos. Dessa polymerer har varit viktiga resurser för människan genom historien. Stärkelse är en viktig näringskälla som det finns rikligt av i sädessorter och potatis. Cellulosa är en viktig komponent i byggmaterial (t.ex. trä), textilier (t.ex. bomullsfibrer), och papper. Stärkelse används dessutom som baStarches and celluloses can be chemically modified in order to affect their physiochemical properties. Modification of these carbohydrate polymers entails derivatising their free hydroxyl groups with functional groups. Which properties are obtained depends on the nature of the functional groups as well as on how they are distributed throughout the polymeric structure of the carbohydrate. Unfortuna

Svensk universitetsgrammatik för nybörjare

Svensk universitetsgrammatik för nybörjare behandlar begreppet grammatik ur olika synvinklar. De inledande kapitlen ägnas åt genomgångar av svenskans språkljud, böjningslära och ordbildning. I de efterföljande kapitlen ges ingående beskrivningar av frasstruktur, primära satsdelar och fullständig satslösning, liksom av grammatikens största enheter, meningar, makrosyntagmer och yttranden. Men förfat