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Simultaneous graphic generalization of vector data sets

Manual cartographic generalization is a simultaneous process. However, most automatic approaches so far have been sequential; generalization operators are applied one at a time in a certain order. This has been the case both for model generalization (generalization of the conceptual model) and graphic generalization. Our research seeks to demonstrate that the graphic part of cartographic generaliz

The Human Ecology of World Systems in East Africa: The Impact of the Ivory Trade

The impact on human ecology of the ivory trade entailed direct and indirect effects. First, the reduction or extermination of elephant populations had direct effects on the vegetation patterns over large areas. Second, the economic activities connected with hunting, transport, and trading affected regional systems of exchange and thereby, indirectly through the political economy, settlements, patt

Autoimmunity to CD38 and GAD in Type I and Type II diabetes: CD38 and HLA genotypes and clinical phenotypes

Aims/hypothesis. Autoantibodies against CD38 have been found in some patients with Type II (non-insulin-dependent) diabetes mellitus and have been shown to stimulate insulin secretion by cultured human islets. We tested whether this new form of autoimmunity, (i) overlaps with anti-GAD autoimmunity, (ii) identifies an insulin-deficient phenotype, (iii) is under the influence of genetic factors. Met

DNA compaction at hydrophobic surfaces induced by a cationic amphiphile

Cetyltrimethylammonium bromide (CTAB) induces partially irreversible compaction of DNA-adsorbed layers on hydrophobic silica. Additionally, there is a synergistic increase in the adsorbed amount when both CTAB and DNA are present as compared to the surface excess concentration of either of the individual components. In this study of the DNA adsorption and DNA-CTAB coadsorption by ellipsometry, emp

Colonization by arbuscular mycorrhizal and fine endophytic fungi in herbaceous vegetation in the Canadian High Arctic

The occurrence of arbuscular mycorrhizal (AM) fungi was surveyed along a latitudinal gradient in Arctic Canada including Banks Island (73degreesN), Devon Island (74degreesN), Ellesmere Island (76degreesN), and the Magnetic North Pole at Ellef Ringnes Island (78degreesN). At Banks Island, AM fungi were present and colonized at a high intensity in all specimens of Potentilla hookeriana Lehm. - Poten

Characteristics of laser-induced incandescence from soot in studies of a time-dependent heat- and mass-transfer model

The temporal behavior of the laser-induced incandescence (LII) signal is often used for soot-particle sizing, which is possible because the cooling behavior of a laser-heated particle is dependent on the particle size. The heat- and mass-transfer model describing the temporal LII-signal behavior has in this work been extended to include the influence of the primary particle-size distribution and t

Dynamics of submerged macrophyte populations in response to biomanipulation

1. A 6-year study (1992-97) of changes in submerged vegetation after biomanipulation was carried out in the eutrophicated Lake Finjasjon, Southern Sweden. Ten sites around the lake were revisited each year. At each site five samples of above-ground biomass were taken at 10 cm water depth intervals. An investigation of the seed bank at the 10 sites, and a grazing experiment where birds and large fi

Temperature and salt content regimes in three shallow ice-covered lakes 2. Heat and mass fluxes

A field study was carried out in three small shallow ice-covered lakes to study heat and mass fluxes and their spatial and temporal variability. During the main part of the winter, the heat flux at the ice-water interface, being of the order 0.5-1, W m(-2), was dominated by conduction from water to ice and did not show any significant variations in time or space. The heat flux from sediments to wa

Unaltered Size-selectivity of the Glomerular Filtration Barrier in Caveolin-1 Knock-out (KO) mice.

The transfer of albumin from blood to tissue has been found to be increased in caveolin-1 knock-out (KO) mice. This has been considered to reflect an increased microvascular permeability, conceivably caused by an increased endothelial production of nitric oxide (NO) in mice lacking caveolin-1. To investigate whether such an increase in endothelial NO-production would also affect the glomerular bar

Optical studies in the Southern Ocean

During the Austral summer of 1997-1998, measurements of absorption, attenuation, downwelling and upwelling irradiance were made in the Southern Ocean along a S-N transect at 6degreesE. Measurements were made to quantify the penetration of ultraviolet B radiation (UVBR) in the water column and daily doses of UVBR at different water depths, to study the attenuation of photosynthetically active radia

Transvaginal ultrasonography of the endometrium in women with postmenopausal bleeding--a Nordic multicenter study

OBJECTIVE: The purpose of this study was to use transvaginal ultrasonographic measurements to find the thickness of the endometrium below which the risk of endometrial abnormality in women with postmenopausal bleeding is low. STUDY DESIGN: This multicenter study was carried out at eight clinics in four Nordic countries. The study included 1168 women with postmenopausal bleeding scheduled for curet

Validity of apparent diffusion coefficient hyperpolarized He-3-MRI using MSCT and pulmonary function tests as references

Purpose: To compare apparent diffusion coefficient (ADC) measurements from hyperpolarized (HP) helium (He-3)-magnetic resonance imaging (MRI) with quantitative data from multislice Computed Tomography (CT) (MSCT) of the whole lungs and pulmonary function tests (PFT). Materials and methods: Twenty-seven subjects, 22 with established emphysema and 5 with preclinical emphysema defined by PFT criteria

A general formula for non-cohesive bed load sediment transport

A bed load transport formula for non-cohesive sediment, based on the bed-shear concept of Meyer-Peter and Muller, was developed and validated for steady flows, oscillatory flows, and combined steady and oscillatory flows. The bed load formula introduced in this study was examined using data from experimental and field measurements for a wide range of flows and sediment conditions, as occurring in

Designing robust preparative purification processes with high performance

In the production of pharmaceutical drugs, a large part of the production costs stem from the downstream processing and the chromatographic purifications required. In order to reduce purification costs the process performance must be increased, which means that the processes need to be less robust since robustness comes with the price of lower process performance, and thus, higher production costs

Lack of respiratory chain Complex I impairs alternative oxidase engagement and modulates redox signaling during elicitor-induced cell death in tobacco.

Alternative oxidase (AOX) functions in stress resistance by preventing accumulation of reactive oxygen species (ROS), but little is known about in vivo partitioning of electron flow between AOX and the cytochrome pathway. We investigated the relationships between AOX expression and in vivo activity in Nicotiana sylvestris and the complex I–deficient CMSII mutant in response to a cell death elicito

The nodal, the new and the old maximum of the Perseid meteor stream

Visual observations of Perseid meteors carried out in 1953-83 at the Onsala Space Observatory are analyzed to study the fine structure of the Perseid meteor stream maximum. Observed hourly rates are corrected for weather conditions and to a zenithal value. The Perseid activity curve is studied (1) for all observed Perseids, (2) for Perseids of app. magnitude 2.0 or brighter. The activity curve for

Folding free energies of 5'-UTRs impact post-transcriptional regulation on a genomic scale in yeast

Using high-throughput technologies, abundances and other features of genes and proteins have been measured on a genome-wide scale in Saccharomyces cerevisiae. In contrast, secondary structure in 5'-untranslated regions ( UTRs) of mRNA has only been investigated for a limited number of genes. Here, the aim is to study genome-wide regulatory effects of mRNA 5'-UTR folding free energies. We performed

History of the reindeer (Rangifer tarandus) in the eastern Baltic region and its implications for the origin and immigration routes of the recent northern European wild reindeer populations

A total of 45 subfossil reindeer (Rangifer tarandus) antlers and bones - artefacts excluded - have been found over the years in the Baltic countries of Estonia, Latvia and Lithuania. The relatively high number of specimens suggests a stable residence of the species in the eastern Baltic region. For the first time, 12 of these finds were radiocarbon-dated. The ages of the samples range between 1208