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Aluminum interacts with negatively charged surfaces in plant roots, causing inhibition of growth and nutrient uptake in plants growing on acid soils. Pectins in the root cell wall form the major cation adsorption surface, with Ca2+ as the main adsorbing cation. Adsorption of Al3+ and Ca2+ to isolated cell wall material of tomato (Lycopersicon esculentum L.) roots was examined at pH 3.00-4.25 and i

Popular Abstract in Swedish En utmaning vid design av interaktiva artefakter är att ta i beräkning den mångfald av digitala ting, system och verktyg människor dagligen sig av ? något som i denna text benämns som en interaktionsekologi. Denna avhandling behandlar tre forskningsteman; för det första hur människor uppfattar och varseblir ljud, och hur vi kan dra nytta av detta när interaktiva ting omA contemporary challenge when designing interactive artifacts is to take into account the wealth of devices, systems, and tools people use every day - here termed an 'interaction ecology'. This thesis addresses three research issues. Firstly, the character of sound perception, and how auditory interaction can be applied to ubiquitous computing. Secondly, how everyday sounds make people aware of su

Several interactions of cytokines with extracellular matrix molecules are mediated by proteoglycans, such as biglycan and decorin. Using surface plasmon resonance, we show for the first time that tumour necrosis factor-alpha (TNF-alpha) binds to both biglycan and decorin with K(d)s of 0.81 microM and 1.23 microM respectively, a binding that was confirmed by Scatchard plots using a solid phase assa

OBJECTIVE: To evaluate a modified uterine artery score based on the pulsatility index and presence or absence of notching in the Doppler velocity waveform recorded from both uterine arteries in relation to the perinatal outcome. METHODS: A retrospective analysis was performed in 741 third-trimester high-risk pregnancies. The uterine artery score was constructed assigning one point to each abnormal

Predatory rule is defined here as a tendency to maximize state revenue, subject to the rulers′ relative bargaining power and transaction costs (Levi, M., 1988, Of Rule and Revenue. Berkeley: Univ. California Press; North, D. C., 1981, Structure and Change in Economic History. New York: Norton). I suggest that the implicit bargaining between Athenian "politicians" and the poor majority generated pr

The standard method used for tagging b-hadrons in the DELPHI experiment at the CERN LEP Collider is discussed in detail. The main ingredient of b-tagging is the impact parameters of tracks, which relies mostly on the vertex detector. Additional information, such as the mass of particles associated to a secondary vertex, significantly improves the selection efficiency and the background suppression

In the water-oxidizing reactions of photosystem II (PSII), a tyrosine residue plays a key part as an intermediate electron-transfer reactant between the primary donor chlorophylls (the pigment P-680) and the water-oxidizing Mn cluster. The tyrosine is deprotonated upon oxidation, and the coupling between the proton reaction and electron transfer is of great mechanistic importance for the understan

Mediatorless, electrochemically driven, redox transformations of TI (type 1) and T2 copper sites in Trametes hirsuta laccase were studied by cyclic voltarnmetry and spectroclectrochernical redox titrations using bare gold electrode. DET (direct electron transfer) between I he electrode and the enzyme was observed under anaerobic conditions. From analysis of experimental data it is concluded that t

The authors analyze how pro-federative representatives of the European Commission exploit the temporal dimension of identity construction within the EU. The paper shows, through the analysis of speeches and statements of Commission members, how efforts are made to construct a common past and visualize a common future to enhance common identities within the EU. The common past is invoked through re

Late Weichselian lake sediments from a site in southern Sweden, were analysed for stable carbon and oxygen isotopes, as well as plant macrofossils and insect remains. By comparison of independent data sets, general climatic changes were demonstrated. Lithological, chemical and stable isotope data reveal two significant climatic oscillations at ca. 12 200-12 000 and ca. 11 000-10 200 yr BP respecti

Fog droplet formation and growth related to fog droplet activation were studied in a polluted region. The joint field experiments were carried out at San Pietro Capofiume in northern Italy during November 1994. It was found that the fog droplet number distribution was continuous in the size region 1-47 µm and that for most of the time the fog consisted of unactivated droplets, i.e. the droplets we

We present time-resolved optical spectrophotometry of the pulsatinghydrogen atmosphere (DA) white dwarf G 117-B15A. We find threeperiodicities in the pulsation spectrum (215 s, 272 s, and 304 s) all ofwhich have been found in earlier studies. By comparing the fractionalwavelength dependence of the pulsation amplitudes (chromatic amplitudes)with models, we confirm a previous report that the stronge

A methacholine or a histamine test is often used to quantitate bronchial responsiveness, in studies investigating the influence of various inhaled stimuli on the responsiveness and composition of bronchoalveolar lavage (BAL) fluid. Histamine has been shown to evoke an inflammatory cell response in BAL fluid. In order to test the influence of the methacholine test on the cellular composition of BAL

A robust method is presented for electrocardiogram (ECG)-based estimation of the respiratory frequency during stress testing. Such ECGs contain highly nonstationary noise and exhibit changes in QRS morphology which, when combined with the dynamic nature of the respiratory frequency, make most existing methods break down. The present method exploits the oscillatory pattern of the rotation angles of

OBJECTIVES: The main purposes were to document manifestations associated with prolonged or clinically unexplained C3 deficiency and to approximate how often hypocomplementaemia of this kind is caused by C3 nephritic factors (C3 NeF), i.e. autoantibodies to alternative pathway C3 convertases. We also wished to distinguish between C3 NeF types I and II and to assess coincident autoantibody responses