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Wasting

Cultural and moral dimensions of waste.

Resistance to phagocytosis in Streptococcus pyogenes

Popular Abstract in Swedish Denna avhandling beskriver studier av de mekanismer varmed bakterien Streptococcus pyogenes undviker komplementdeposition och fagocytos.Phagocytosis of Streptococcus pyogenes is complement dependent. However, the cell wall-associated M protein, which exists in >100 different serotypes (M types), enables the bacteria to evade phagocytosis. To analyze the mechanisms by which M protein confers this ability we used, as model systems, two representative M proteins, the M22 and M5 proteins, which have properties typical for many M prote

Reduction of RV pacing by continuous optimization of the AV interval

Background: In patients requiring permanent pacing, preservation of intrinsic ventricular activation is preferred whenever possible. The Search AV+ (SAV+) algorithm in Medtronic EnPulse(TM) dual-chamber pacemakers can increase atrioventricular (AV) intervals to 320 ms in patients with intact or intermittent AV conduction. This prospective, multicenter study compared the percentage of ventricular p

A note on the local nilpotence of 4-Engel groups

Recently Havas and Vaughan-Lee proved that 4-Engel groups axe locally nilpotent. Their proof relies on the fact that a certain 4-Engel group T is nilpotent and this they prove using a computer and the Knuth-Bendix algorithm. In this paper we give a short handproof of the nilpotency of T.

On the use of MOS varactors in RF VCOs

This paper presents two 1.8 GHz CMOS voltage-controlled oscillators (VCOs), tuned by an inversion-mode MOS varactor and an accumulation-mode MOS varactor, respectively. Both VCOs show a lower power consumption and a lower phase noise than a reference VCO tuned by a more commonly used diode varactor. The best overall performance is displayed by the accumulation-mode MOS varactor VCO. The VCOs were

Directions in Mathematical Systems : Theory and Optimization

This volume provides a compilation of recent contributions on feedback and robust control, modeling, estimation and filtering. They were presented on the occasion of the sixtieth birthday of Anders Lindquist, who has delivered fundamental contributions to the fields of systems, signals and control for more than three decades. His contributions include seminal work on the role of splitting subspace

Dominant pole placement for multi-loop control systems

This paper proposes a method for multi-loop PI controller design which can achieve dominant pole placement for two input two output processes. It is an extension of the original dominant pole design (PID Controllers: Theory, Design, and Tuning, Instrument Society of America, Research Triangle park, NC, 1995.) for SISO systems. Unlike its SISO counterpart, where the controller parameters can be obt

Resonant acceptor states in uniaxially strained semiconductors

A new approach to calculating the parameters of resonant states is proposed, which also makes it possible to determine the probabilities of the resonant scattering and capture probabilities at the resonant state. This approach is based on the application of the method of configuration interaction, which was proposed for the first time by Fano for an analysis of field ionization of the helium atom.

Synchronous oscillations of length and stiffness during loaded shortening of frog muscle fibres

A study was made of the damped oscillations in fibre length that are observed when isolated muscle fibres from the frog are released during the plateau of an isometric tetanus to shorten against a constant load (force clamp recording) near the isometric level (temperature, 1.0-11.0 C; initial sarcomere length, 2.25 m). 2. The oscillatory length changes of the whole fibre were associated with simil

Cold acclimation of carrots during storage mechanical properties and antifreezing protein.

Changes in the composition of carrot cell wall proteins were investigated, associating metabolic changes during long-term storage with changes in mechanical properties. Harvested carrots accumulate an antifreezing protein in their cell walls reaching a maximum level after 12 weeks of storage at 0°C, followed by a gradual decrease. During the same period of time, there is a decrease in the slicing

Microorganisms for Desulfurization of Coal: the Influence of Leaching Compounds on their Growth

An investigation was undertaken to outline how microorganisms suggested for use in coal desulphurization are affected by compounds leached from coal. Three species of the genus Sulfolobus were studied. Sulfolobus acidocaldarius was seen to be affected by compounds leached from coal more negatively than Sulfolobus brierleyi and Sulfolobus solfataricus. It was observed that certain conditions during

Tree-limit ecotonal response to Holocene climate change in the Scandes Mountains of west-central Sweden

Popular Abstract in Swedish Under den geologiska period som kallas kvartärtiden (de senaste 2,6 miljoner åren) har flera istider (glacialer) och mellanistider (interglacialer) avlöst varandra enligt ett mönster där glacialerna varar i ungefär 100000 år och mellanistiderna i ca 10000 år. Under istiderna täcktes stora landområden på norra halvklotet, bl.a. Skandinavien, av väldiga inlandsisar. Då deThe aim of this thesis was to reconstruct the Holocene vegetational and climatic development in the Sylarna-Storulvån area, western Jämtland, in the central Scandes Mountains. Temporal trends and fluctuations in the elevation and vegetational character of the tree-limit ecotone were studied mainly by means of pollen and plant macrofossil analysis of two lake sediment sequences (Lakes Stentjärn and

The Refined Structure of dUTPase from Escherichia coli

Deoxyuridine 5'-triphosphate nucleotidohydrolase (dUTPase, E.C. 3.6.1.23) catalyzes the hydrolysis of dUTP to dUMP and pyrophosphate and is involved in nucleotide metabolism and DNA synthesis. A crystal of the recombinant E. coli enzyme, precipitated from polyethylene glycol mixtures in the presence of succinate at pH 4.2, was used to collect synchrotron diffraction data to 1.9 Å resolution, in sp

Controlling excitonic wavepacket motion in the PS1 core-antenna system

Sub-picosecond laser pulse driven localization of electronic excitation energy is suggested for a biological chromophore complex. Based on an exciton model of the photosynthetic core antenna PSI of Synechococcus elongatus the shape of the respective laser pulse is calculated using optimal control theory combined with a density matrix theory accounting for energy relaxation and dephasing caused by

Streptokinase activates plasminogen bound to human group C and group G streptococci through M-like proteins

An ability to interact with plasminogen or plasmin could provide micro-organisms with a mechanism for invasion. Thus, group A, C and G streptococci secrete streptokinase which binds and activates plasminogen. Some streptococci also express surface structures which bind plasminogen without causing its activation. Plasminogen-binding surface proteins were extracted from one group C and one group G s

Off-axis primary-dose measurements using a mini-phantom

The characterization of the incident photon beam is usually divided into its dependence on collimator setting (head-scatter factor) and off-axis position (primary off-axis ratio). These parameters are normally measured "in air" with a build-up cap thick enough to generate full dose build-up at the depth of dose maximum. In order to prevent any influence from contaminating electrons, it has been re