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Linear congruential trellis source codes: Design and analysis

Rate-distortion trellis source codes are developed for quantizing memoryless IID sources. The codes are generated by simple linear congruential recursions. The method generates codes at a variety of rates including fractional ones; reproducer sets can be large, a crucial advantage with certain sources. Axioms for good code construction are developed that are based on recursion properties, certain

Crystallization and preliminary X-ray diffraction studies of beta-phosphoglucomutase from Lactococcus lactus

beta-Phosphoglucomutase (beta-PGM), a 28 kDa monomer, catalyzes the reversible conversion of beta-D-glucose-1-phosphate to beta-D-glucose-6-phosphate in maltose metabolism in a variety of organisms. Sequence analysis of beta-PGM indicates that it is a member of the haloacid dehalogenase (HAD) enzyme superfamily, which evolved to cleave C-Cl, C-P and C-OP bonds in a variety of substrates. beta-PGM

Glacial geology and palaeo-ice dynamics of two ice-sheet margins, Taymyr Peninsula, Siberia and Jameson Land, East Greenland

Popular Abstract in Swedish Arktis utgör en viktig del i Jordens miljö och vad som händer där har stor påverkan på det globala klimatet, samtidigt som området är mycket känsligt för förändringar. Under kvartärtiden har stora isar flera gånger täckt Skandinavien, Ryssland, Sibirien och Nordamerika och täcker än idag stora delar av Grönland. Isarna har lämnat spår (landformer och sediment) efter sigThe North Taymyr ice-marginal zone (NTZ) on the Taymyr Peninsula, Arctic Siberia and the Ugleelv Valley on Jameson Land, East Greenland, have been investigated with the aim of reconstructing the glacial history, including depositional processes and environments. Geomorphological, sedimentological, stratigraphical and remote sensing methods have been combined to give a comprehensive view of develop

The matter of white matter in Alzheimer's disease. -On white matter disease from neuropathology and neuroimaging to clinical presentation.

Popular Abstract in Swedish Hjärnan består av hjärnbarken, även kallad den grå substansen, och den underliggande vita substansen. Den grå substansen med alla nervceller svarar bland annat för våra kognitiva funktioner som gör var och en av oss till unika individer. Medvetande, minne, språk och tal liksom ilska och glädje är alla exempel på egenskaper och funktioner som styrs från den grå substanseAlzheimer's disease (AD) is the most prevalent type of dementing disorder. The cortical pathology of AD has been recognized for almost a century. In later years, an associated pathological feature of AD has been identified which affects the white matter. This white matter disease (WMD), defined in the microscope, consists of a subtotal tissue loss of the white matter structural components. WMD is

Aqueous two-phase affinity partitioning of biotinylated liposomes using neutral avidin as affinity ligand

Biotinylated small unilamellar liposomes were affinity partitioned in an aqueous poly(ethylene glycol)-dextran two-phase system using avidin coupled to dextran as affinity ligand. In the absence of affinity ligand more than 90% of the liposomes partitioned in the poly(ethylene glycol)-rich top phase, whereas in its presence more than 95% partitioned in the dextran-rich bottom phase. For this redis

Regression analysis and modelling of data acquisition for SELDI-TOF mass spectrometry.

Motivation: Pre-processing of SELDI-TOF mass spectrometry data is currently performed on a largel y ad hoc basis. This makes comparison of results from independent analyses troublesome and does not provide a framework for distinguishing different sources of variation in data. Results: In this article, we consider the task of pooling a large number of single-shot spectra, a task commonly performed

A direct search for stable magnetic monopoles produced in positron-proton collisions at HERA

A direct search has been made for magnetic monopoles produced in e(+)p collisions at a centre of mass energy of 300 GeV at HERA. The beam pipe surrounding the interaction region in 1995-1997 was investigated using a SQUID magnetometer to look for stopped magnetic monopoles. During this time an integrated luminosity of 62 pb(-1) was delivered. No magnetic monopoles were observed and charge and mass

Comparative studies of the S0 and S2 multiline electron paramagnetic resonance signals from the manganese cluster in Photosystem II

Electron paramagnetic resonance (EPR) spectroscopy is one of the major techniques used to analyse the structure and function of the water oxidising complex (WOC) in Photosystem II. The discovery of an EPR signal from the S0 state has opened the way for new experiments, aiming to characterise the S0 state and elucidate the differences between the different S states. We present a review of the bioch

Investment in immune defense is linked to pace of life in house sparrows

The evidence for a relationship between life history and immune defense is equivocal, although the basic premise is intuitively appealing: animals that live short lives and reproduce early and rapidly should not waste resources on defenses they might never use. One possible reason for a lack of strong support for this hypothesis could be the inherent complexity of the vertebrate immune system. Ind

Role of N-linked glycans on bunyamwera virus glycoproteins in intracellular trafficking, protein folding, and virus infectivity.

The membrane glycoproteins (Gn and Gc) of Bunyamwera virus (BUN, family Bunyaviridae) contain three potential sites for the attachment of N-linked glycans: one site (N60) on Gn and two (N624 and N1169) on Gc. We determined that all three sites are glycosylated. Digestion of the glycoproteins with endo-beta-N-acetylglucosaminidase H (endo H) or peptide:N-glycosidase F revealed that Gn and Gc differ

Separation of amino acids, peptides and proteins on molecularly imprinted stationary phases.

Stationary phases, to be used in high-performance liquid chromatography, were tailor-made for the separation of amino acids, peptides and proteins. The stationary phases were prepared by molecular imprinting, applying two different approaches. Low-molecular-mass compounds were imprinted in bulk polymers by copolymerization of functional monomers and cross-linkers in the presence of the compound of

Occupational Perspectives on Health in People with Schizophrenia

Popular Abstract in Swedish Denna avhandling har bidragit med systematisk information om hur personer med schizofreni lever sitt vardagsliv, och resultaten har visat på signifikanta relationer mellan ett aktivitetsperspektiv och hälsa. Avhandlingen består av fem studier. De första två är kvalitativa studier som handlar om tidsanvänding i förhållande till aktivitetsutförandet och aktivitetsengagemaThe thesis has provided with systematic information about how people with schizophrenia live their everyday life, and the results have shown significant relationships between occupational perspectives and health. The thesis departed in two in-depth studies that concerned time use and occupational engagement in relation to what people with schizophrenia do in their everyday life, with whom they are

Indications of improved cognitive development at one year of age among infants born very prematurely who received care based on the Newborn Individualized Developmental Care and Assessment Program (NIDCAP)

Background and Objective: Care based on the Newborn Individualized Developmental Care and Assessment Program (NIDCAP) has been reported to exert a positive impact on the development of prematurely born infants. The aim of the present investigation was to determine the effect of such care on the 1-year development of infants born with a gestational age of less than 32 weeks. Methods: All surviving

Observation of fusion-like residues in energetic nuclear collisions at the Celsius storage ring

Recent experiments at the CELSIUS storage ring of Uppsala, Sweden, have revealed the existence of high momentum transfer target-like fragments contrary to expectations. Recoiling heavy fragments in the reaction of 250 MCV/nucleon N-14 on Xe-131 have been measured at 10degrees with respect to the beam direction with specially designed recoil telescopes, Simulations with the Boltzmann-Uehling-Uhlenb

Degradation of toxaphene in water during anaerobic and aerobic conditions

The degradation of technical toxaphene in water with two kinds of bioreactors operating in sequence was studied. One packed bed reactor was filled with Poraver(R) (foam glass particles) running at anaerobic conditions and one suspended carrier biofilm reactor working aerobically. Chemical oxygen demand (COD), chloride, sulphate, pH, dissolved oxygen, total toxaphene and specific toxaphene isomers