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Stochastic modelling and optimal spectral estimation of EEG signals

The study of a time-frequency image is often the method of choice to address key issues in cognitive electrophysiology. The quality of the time-frequency representation is crucial for the extraction of robust and relevant features, thus leading to the demand for highly performing spectral estimators. We consider a stochastic model, known as Locally Stationary Processes, based on the modulation in

Physico-chemical characterisation of membrane-bound and water-soluble forms of Bacillus subtilis cytochrome c-550

Cytochrome c-550 of the Gram-positive bacterium, Bacillus subtilis, is a membrane-bound 13-kDa protein encoded by the cccA gene. The cytochrome has been proposed to be comprised of an N-terminal membrane anchor domain (about 30 residues) which spans the cytoplasmic membrane in an alpha-helical conformation and a C-terminal heme domain (about 70 residues) which is located on the outside of the cyto

Glutamyl-tRNA reductase activity in Bacillus subtilis is dependent on the hemA gene product

The Bacillus subtilis hemAXCDBL operon encodes enzymes for the synthesis of 5-aminolaevulinic acid via the C5 pathway (hemA and hemL) and uroporphyrinogen III (hemB, hemC and hemD). B. subtilis HemA protein (molecular mass 50 kDa) was overexpressed in hemA mutants of both Escherichia coli and B. subtilis. A mutant B. subtilis HemA protein with a Cys to Tyr change at position 105 was also overexpre

Bacillus subtilis holo-cytochrome c-550 can be synthesized in aerobic Escherichia coli

Bacillus subtilis membrane-bound holo-cytochrome c-550 was found to be expressed from the structural gene cloned on a plasmid vector in aerobically grown Escherichia coli and exhibited normal biochemical properties. This occurs despite the lack of endogenous eytochrome c and suggests that eytochrome c-heme lyase activity is also present in aerobic E. coli. The membrane topology of B. subtilis eyto

Homogeneous sample preparation for automated high throughput analysis with matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry

This work presents a simple method for obtaining homogeneous sample surfaces in matrix-assisted laser desorption/ionisation time-of-flight mass spectrometry (MALDI-TOFMS) for the automated analysis of peptides and proteins. The sample preparation method is based on applying the sample/matrix mixture onto a pre-deposited highly diluted matrix spot. The pre-deposited crystals act as seeds for the ne

Fluorescence polarisation for immunoreagent characterisation

Antibodies were characterised using fluorescence polarisation, a homogeneous assay technique in which all reagents are in solution. Kinetic studies on the association and dissociation of the immunocomplex were performed. A competitive assay was used and the sensitivities, operational linearities, as well as the specificities of the immunoassays were experimentally determined for various antibody p

Genetic signals of high-altitude adaptation in amphibians : A comparative transcriptome analysis

Background: High-altitude adaptation provides an excellent system for studying how organisms cope with multiple environmental stressors and interacting genetic modifications. To explore the genetic basis of high-altitude adaptation in poikilothermic animals, we acquired transcriptome sequences from a high-altitude population and a low-altitude population of the Asiatic toad (Bufo gargarizans). Tra

Towards in-cylinder chemical species tomography on large-bore IC engines with pre-chamber

A feasibility study is presented and the achieved key design milestones towards the first application of Chemical Species Tomography by Near-IR Absorption Tomography on a heavy duty, large-bore marine engine to visualise relative mixture strength are described. The engine is equipped with pre-chamber ignition and operates using Liquefied Natural Gas with >88.9% methane content. Operation of the en

A BiCMOS single ended multiband RF-amplifier and mixer with DC-offset and second order distortion suppression

Direct conversion receivers are widely used for full duplex mobile radio communication systems. This paper describes a novel SAW-less single-ended RF amplifier connected to a single-ended mixer with a feedback loop that suppresses the second-order distortion from TX cross modulation of the LO-leakage as well as DC-offset at the mixer output. In Monte Carlo simulations the design achieves +47 dBm m

Osannolika händelser och den svenska realistiska romanen : Ett estetiskt och existentiellt bekymmer

Avhandlingens ämne är osannolika händelser i den realistiska romanen. Den övergripande idén är att realismen utmärks av att osannolika händelser hanteras utifrån ett dubbelt perspektiv: både som ett existentiellt och ett estetiskt bekymmer. Som ett existentiellt bekymmer representerar den narrativa fiktionsberättelsens osannolika händelser den ständigt närvarande möjligheten att en oförutsägbar ocThis thesis deals with improbable events in the realistic novel. The overarchingidea is that realism is distinguished by dealing with improbable events on thebasis of a double perspective: both as an existential and as an aesthetic problem.As an existential problem the improbable events of narrative fiction representthe constantly present possibility of an unexpected and unforeseen event suddenly

Increased Melatonin Signaling Is a Risk Factor for Type 2 Diabetes

Type 2 diabetes (T2D) is a global pandemic. Genome-wide association studies (GWASs) have identified >100 genetic variants associated with the disease, including a common variant in the melatonin receptor 1 b gene (MTNR1B). Here, we demonstrate increased MTNR1B expression in human islets from risk G-allele carriers, which likely leads to a reduction in insulin release, increasing T2D risk. Accordin

Platelet-derived growth factor-BB has neurorestorative effects and modulates the pericyte response in a partial 6-hydroxydopamine lesion mouse model of Parkinson's disease

Parkinson's disease (PD) is a neurodegenerative disease where the degeneration of the nigrostriatal pathway leads to specific motor deficits. There is an unmet medical need for regenerative treatments that stop or reverse disease progression. Several growth factors have been investigated in clinical trials to restore the dopaminergic nigrostriatal pathway damaged in PD. Platelet-derived growth fac

Reproductive isolation of sympatric forms of the understorey palm Geonoma macrostachys in western Amazonia

The evolution of a mechanism for attaining reproductive isolation between two diverging populations is a key step in the speciation process. We studied phenotypic variation, genetic differentiation, spatial distribution and reproductive ecology in two sympatric forms of the understorey palm Geonoma macrostachys in lowland tropical rainforest in Amazonian Ecuador. The two forms were morphologically

Model of the evolution of mounds placed in the nearshore

A one-dimensional mathematical model is presented that describes the cross-shore evolution of a long linear mound of noncohesive sediment placed in the nearshore and exposed to non-breaking waves. The equation for the transport rate accounts for wave asymmetry and gravity, and the net rate is expressed by reference to an equilibrium profile shape. Simplifications reduce the governing equation for

Structural biology of starch-degrading enzymes and their regulation

Starch is a major energy source for all domains of life. Recent advances in structures of starch-degrading enzymes encompass the substrate complex of starch debranching enzyme, the function of surface binding sites in plant isoamylase, details on individual steps in the mechanism of plant disproportionating enzyme and a self-stabilised conformation of amylose accommodated in the active site of pla

Capto™ Resins for Chromatography of DNA : A Minor Difference in Ligand Composition Greatly Influences the Separation of Guanidyl-Containing Fragments

The differences in chromatographic behaviour of individual deoxynucleotides as well as small single-stranded and double-stranded DNA molecules have been examined for two resins from the Capto family: Capto Adhere and Capto Q ImpRes. Capto Adhere carries a multimodal ligand which combines strong anion with aromatic recognition, while Capto Q ImpRes is a strong anion exchanger with a chemically simi

Origin of Harmattan dust settled in Northern Ghana - Long transported or local dust?

The Harmattan is a dry, dust-laden continental wind which has its origin in the Bodélé Depression in the Chad basin. In Ghana the Harmattan can be experienced from November to March, when the Harmattan replaces the dominant south westerly maritime Monsoon wind. The hypothesis of this study is that the majority of dust deposited in northern Ghana may not be from the original Harmattan source in the