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Popular Abstract in Swedish De äldsta hajfossil man känner till kommer från devonperioden och är minst 380 miljoner år gamla. Under Mesozoikum (trias, jura och krita) dominerades hajfaunorna av hybodonta hajar under trias och första halvan av jura medan de moderna hajarna (Neoselachii) tog över från slutet av jura och numera är de enda levande hajarna på vår planet. Detta arbete har fokuserats påThe Jurassic and Early Cretaceous selachian faunas of Scania (Skåne), southern Sweden and the island of Bornholm (Denmark) have been investigated. Three Early Jurassic shark tooth assemblages have been recorded and investigated, one from Hettangian strata and the other two from Pliensbachian sediments. The Hettangian assemblage originates from non-marine deposits in the southern part of Helsingbor

Esterification of p-hydroxybenzoic acid, a very weak estrogenic compound, with the daucane alcohol jaeschkeanadiol (1b) leads to a spectacular magnification of the estrogenic activity. To identify the structural elements responsible for this effect, the terpenoid core of jaeschkeanadiol p-hydroxybenzoate (ferutinin, 1a) was modified, capitalizing on the presence of two functionalities, the monoacy

We consider the problem of decomposing polygons (with holes) into various types of simpler polygons. We focus on the problem of partitioning a rectilinear polygon, with holes, into rectangles, and show an Omega (n log n) lower bound on the time-complexity. The result holds for any decomposition, optimal or approximative. The bound matches the complexity of a number of algorithms in the literature,

To assess the potential roles of protein Z (PZ) and protein Z-dependent protease inhibitor (ZPI) in venous thrombosis, their plasma levels were measured in 426 individuals with venous thrombosis and 471 control individuals participating in the Leiden Thrombophilia Study. A relationship between the level of PZ or ZPI and venous thrombosis was not detected in the overall case-control study. PZ and Z

Proposed is a frequency selective (FS) subspace-based method for determining the model order. A study is made of its performance when applied to estimating the number of sinusoids in white noise. Employing an FS-version of the ESPRIT algorithm, the recent ESTER model order estimation algorithm is extended to allow for the model order estimation on a frequency subset.

Four exposures of Chicxulub impact ejecta along the Mexico-Belize border have been sampled and analyzed for major and trace element abundances. The ejecta deposits consist of a lower spheroid bed, containing clay and dolomite spheroids, and an upper diamictite bed with boulders and clasts of limestone and dolomite. The matrix of both beds is composed of clay and micritic dolomite. The rare earth e

A number of techniques for non-linear analysis of time series data have been developed in recent years and applied in many environmental sciences. In this paper, some of these techniques are reviewed and their usefulness for coastal morphological data assessed, with examples in coastal morphology and related fields where these are available. The methods reviewed are time-delay embedding techniques

Extensive studies of mice deficient in one or several cytokine receptors have failed to support an indispensable role of cytokines in development of multiple blood cell lineages. Whereas B1 B cells and Igs are sustained at normal levels throughout life of mice deficient in IL-7, IL-7R{alpha}, common cytokine receptor gamma chain, or flt3 ligand (FL), we report here that adult mice double deficient

The single most important factor related to the development of diabetic retinopathy is the duration of diabetes. Little is known about the underlying mechanisms, but many factors have been suggested to be involved, among them derangements in plasma lipids and plasma lipoproteins. In the present study we examined the relation between plasma lipids, plasma lipoproteins, and the duration of diabetes

Atrial electrical and contractile remodeling have been demonstrated to coincide during atrial fibrillation (AF) in experimental studies. We explored whether electrical and contractile remodeling correlate in man and explored its clinical implications. METHODS: Forty-nine patients with persistent AF were studied. Electrical remodeling was assessed noninvasively using spectral analysis to estimate t

The sediment-landform associations of the northern Taymyr Peninsula in Arctic Siberia tell a tale of ice sheets advancing from the Kara Sea shelf and inundating the peninsula, probably three times during the Weichselian. In each case the ice sheet had a margin frozen to its bed and an interior moving over a deforming bed. The North Taymyr ice-marginal zone (NTZ) comprises ice-marginal and supragla

BACKGROUND: During the two recent decades, advocacy has been a topic of much debate in the nursing profession. Although advocacy has embraced a crucial role for nurses, its extent is often limited in practice. While a variety of studies have been generated all over the world, barriers and facilitators in the patient advocacy have not been completely identified. This article presents the findings o

Popular Abstract in Swedish Den huvudsakliga hämmande signalsubstansen i hjärnan är GABA (gamma-aminobutyric acid, gamma-aminosmörsyra). GABA finns i ungefär hälften av alla nervceller i hjärnan och alla nervceller i hjärnan antas ha receptorer som binder GABA. Om man tänker på alla de normala neurologiska funktioner samt rubbningar där GABA är involverat är det inte svårt att förstå GABA:s oerhörInhibitory neurotransmission in the brain is mostly mediated by gamma-aminobutyric acid type A (GABAA) receptors. These receptors are involved in both phasic inhibition (point-to-point inhibition, synaptic transmission) and tonic inhibition (diffuse form of inhibition, brain homeostasis). In this thesis the functional and pharmacological properties of GABAA receptors expressed in brain slices or i

Three sesquiterpenoids that are found in the edible mushrooms Lactarius deliciosus, L. deterrimus and L. sanguifluus, have been assayed for biological activity. The compounds tested were a stearic acid ester of a sesquiterpene (I) and a sesquiterpene aldehyde (lactaroviolin, II) and alcohol (deterrol, III). The assays used were for mutagenic activity in the Ames Salmonella assay, for antimicrobial

Both theoretical and experimental studies of pleural fluid dynamics and lung buoyancy during steady-state, apneic conditions are presented. The theory shows that steady-state, top-to-bottom pleural-liquid flow creates a pressure distribution that opposes lung buoyancy. These two forces may balance, permitting dynamic lung floating, but when they do not, pleural-pleural contact is required. The ani