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Earth System governmentality Reflections on science in the Anthropocene
This paper examines Earth System Science as a novel approach to global environmental change research. Drawing upon Michel Foucault's governmentality concept, the paper opens up the Earth System metaphor to political analysis and asks what it does to our understanding of nature and society as a governable domain. We trace the scientific practices that have produced the Earth System as a thinkable a
Novel nanoelectronic device applications based on the nonlinearity of three-terminal ballistic junctions
Nanometer-scale electron devices containing three-terminal ballistic junctions are fabricated by electron-beam lithography on InP/InGaAs two-dimensional electron gas materials. Based on the intrinsic nonlinearity of the devices, frequency mixer, phase detector and RS flip-flop memory functioning at room temperature are successfully achieved. The devices have simple structure layout and small size,
Effects of anoxia and sulfide on concentrations of total and methyl mercury in sediment and water in two Hg-polluted lakes
Between May and December 1996, monthly samples of surface sediment (0-1 cm), settling matter, and water were taken at a shallow site and a deep site in each of two consecutive Hg-polluted riverine lakes. In the upper lake, the sediment was polluted also with cellulose fiber. Both hypolimnia turned anoxic, but sulfide was detected only in the upper lake. When sulfide appeared, hypolimnetic methyl m
CD44-stimulated human B cells express transcripts specifically involved in immunomodulation and inflammation as analyzed by DNA microarrays
A number of studies have implicated a role for the cell surface glycoprotein CD44 in several biologic events, such as lymphopoiesis, homing, lymphocyte activation, and apoptosis. We have earlier reported that signaling via CD44 on naive B cells in addition to B-cell receptor (BCR) and CD40 engagement generated a germinal center-like phenotype. To further characterize the global role of CD44 in B d
An automated on-line multidimensional HPLC system for protein and peptide mapping with integrated sample preparation
A comprehensive on-line two-dimensional 2D-HPLC system with integrated sample preparation was developed for the analysis of proteins and peptides with a molecular weight below 20 kDa. The system setup provided fast separations and high resolving power and is considered to be a complementary technique to 2D gel electrophoresis in proteomics. The on-line system reproducibly resolved similar to1000 p
Electrocardiographic changes in stroke patients without primary heart disease
Consecutive electrocardiograms were recorded in 28 stroke patients without signs of primary heart disease. Individuals with subarachnoidal haemorrhage, or electrolyte disturbances were excluded. A computerized tomography of the brain was performed in each case and showed a cerebral haemorrhage (n = 4), cortical infarction (n = 6), subcortical infarction (n = 14) and normal finding (n = 4). One pat
The Kullaberg peninsula – a glimpse of the Proterozoic evolution of SW Fennoscandia
The Kullaberg peninsula in NW Skåne renders km-long, continuous exposures of the Proterozoic crystalline basement. We report ion microprobe (SIMS) U–Pb zircon ages for six key lithologies at Kullaberg that constrain the geological history of SW Fennoscandia for a considerable time period. Igneous zircon in three varieties of gneiss granite yield ages of 1694±7 Ma, 1693±7 Ma and 1663±14 Ma, in the
DDT-fate in tropical and temperate regions
Abstract is not available
Recovery of cellulases after hydrolysis by adsorption on steam-pretreated willow
Titanium-hydrogen peroxide interaction: model studies of the influence of the inflammatory response on titanium implants
In vitro studies of titanium and TiO2 as well as other metals were carried out to investigate the role of these metals in the inflammatory response through the Fenton reaction. The TiOOH matrix formed traps the superoxide radical, so that no or very small amounts of free hydroxyl radicals are produced. Ellipsometry and spin trapping with spectrophotometry and electron spin resonance (ESR) were use
Use of neural networks to improve quality control of interpretations in myocardial perfusion imaging
Background: The aim of this study was to explore the feasibility of using a technique based on artificial neural networks for quality assurance of image reporting. The networks were used to identify potentially suboptimal or erroneous interpretations of myocardial perfusion scintigrams (MPS). Methods: Reversible perfusion defects (ischaemia) in each of five myocardial regions, as interpreted by on
The unequal exchange of time and space: Toward a non-normative ecological theory of exploitation
Uteroplacental and luteal circulation in normal first-trimester pregnancies: Doppler ultrasonographic and morphologic study
OBJECTIVE: Our purpose was to establish reference data representative of normal findings at transvaginal color and spectral Doppler ultrasonographic examination of the uteroplacental and luteal circulation in the first trimester and to relate the Doppler findings to morphologic data. STUDY DESIGN: A cross-sectional study was performed of 64 uncomplicated pregnancies of 5 to 11 completed gestationa
Homogenization of woven materials
The effective electric and magnetic material properties of a complex (two-component) mixture are addressed. The mixture is periodic in two directions and has a finite thickness in the third direction. Specifically, the explicit problem of finding the effective electric parameters for slab that has been reinforced by a layer (or several layers) of glass fiber is investigated. The homogenization pro
Ramet dynamics in a centrifugally expanding clonal sedge: a matrix analysis
Carex humilis is a clonal sedge that can form distinct rings of densely aggregated ramets. We hypothesize that rings form because both production of new ramets and ramet dispersal are positively correlated to ramet size. This would lead to an overrepresentation of fast-moving and large ramets with high ramet production at the periphery, whereas slow-moving and small ramets with low ramet productio
Size- and compostition-controlled Au-Ga aerosol nanoparticles
A simple gas-phase method has been developed for producing size- and composition-controlled nanoparticles of binary alloys. The process includes the formation and classification of aerosol nanoparticles of one material and the subsequent condensation of a controlled shell of another. The shell thickness is controlled by the evaporation temperature of the second material. Here we study the Au-Ga sy
Association testing of common variants in the insulin receptor substrate-1 gene (IRS1) with type 2 diabetes
Aims/hypothesis Activation of the insulin receptor substrate-1 (IRS1) is a key initial step in the insulin signalling pathway. Despite several reports of association of the G972R polymorphism in its gene IRS1 with type 2 diabetes, we and others have not observed this association in well-powered samples. However, other nearby variants might account for the putative association signal. Subjects and
Effects of propofol on desipramine-sensitive [3H]-noradrenaline uptake kinetics in rat femoral artery
BACKGROUND: The intravenous anaesthetic propofol inhibits the neuronal uptake of noradrenaline (uptake1) from the vascular sympathetic neuromuscular junction, resulting in an enhancement of the sympathetic neurotransmission. This could be important for maintenance of blood pressure during propofol anaesthesia. The aim of the present study was to determine how propofol influences the kinetics of up
Effect of high-temperature drying on properties of Norway spruce and larch
Abstract in German Bei der Holztrocknung können Änderungen der Holzeigenschaften aufgrund von Behandlungstemperatur und -dauer auftreten. Erhöhte Trocknungstemperaturen führen im Allgemeinen zu einer Verkürzung der Trockendauer und einer negativen Beeinflussung einiger Eigenschaften. Die vorliegende Studie behandelt die Auswirkung unterschiedlicher Trocknungstemperaturen (80, 120 und 170 °C) auf GIn timber drying, mechanical properties may be changed due to treatment temperature and treatment duration. In general, when increasing the kiln temperature, drying time is decreased and some timber properties are negatively affected. In this study, the effect of different drying temperatures (80, 120 and 170 degrees C) on equilibrium moisture content and sorption rate, on bending strength and sti