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The crystal structure of superoxide dismutase (SOD) from the hyper thermophile Sulfolobus solfataricus has been determined at 2.3 Å resolution by molecular replacement and refined to a crystallographic R-factor of 16.8 % (Rfree 19.8 %). The crystals belong to the space group C2 (a = 76.3 Å, b = 124.3 Å,c = 60.3 Å, β = 128.8°) with two identical monomers in the asymmetric unit. The monomer has a mo

In this note we establish that the probability that the simple random walk on Z2 returns to its origin before leaving a strip of width L has asymptotically the same probability as the one for hitting the origin before exiting the centered box of the same size. We also generalize this theorem for fairly arbitrary sequences of increasing sets in Z2.

The subject of the dissertation is a theoretical discussion of the possibilities and limitations of reformist politics. Theories of social justice and democracy are discussed and assessed in relation to the argument that reformist politics, which underlie the welfare state program, is a contradictory politics. It is suggested that it is contradictory because reformism is constituted by a double re

Stomatal conductance (gs), net photosynthesis (An) and twig water potential (Ct) were measured in mature silver birch (Betula pendula) during 3 years in southern Sweden. Measurements from 2 years were used to parameterise three different gs models and measurements from a 3rd year were used to validate these models. Two different multiplicative stomatal models were used. In one of these, the gs res

The subject of constrained controlled mechanical (“mechatronic”) systems in descriptor form is a field of current research in mechanical engineering, control theory and applied mathematics. It is essentially based on the progress in numerical mathematics on the solution of differential-algebraic equations, cf. [1–3] and on the developments in control theory on singular (or descriptor) systems, cf.

heory predicts that electrons emitted from independent electron sources (metallic contacts) can nevertheless interfere. This interference is manifest in an exchange contribution to the shot noise correlation of currents at different contacts of a mesoscopic conductor. A geometry has been proposed in which second order (single particle) interference due to superposition of amplitudes is absent but

OBJECT: By pursuing a policy of very early aneurysm treatment in neurosurgical centers, in-hospital rebleeds can be virtually eliminated. Nonetheless, as many as 15% of patients with aneurysm rupture suffer ultraearly rebleeding with high mortality rates, and these individuals are beyond the reach of even the most ambitious protocol for diagnosis and referral. Only drugs given immediately after th

Comparisons of absorption spectra of photosystem II (PSII) core complexes with those of isolated CP43, CP47 and D1/D2/cyt b559 complexes show broadenings and shifts upon disassembly of the PSII core material. Spectra of PSII cores isolated from plants and cyanobacteria reveal marked changes in energies and intensities of the sharp features associated with P680. Low-temperature, illumination-induce

The affinity of metal chelates for amino acids, such as histidine, is widely used in purifying proteins, most notably through six-histidine `tails'. We have found that metal affinity interactions can also be applied to separation of single-stranded nucleic acids through interactions involving exposed purines. Here we describe a metal affinity precipitation method to resolve RNA from linear and pla

The emission time sequence of neutrons, protons, and deuterons is deduced from velocity-gated two-particle correlation functions in E/A = 61 MeV 36Ar+112,124Sn reactions. A dependence of the emission sequence on the isospin of the emitting source is observed.

We describe the history, construction, and use of a portable walk-in wader trap (i.e., modified Ottenby trap) designed to be used in field expedition conditions. It is rectangular-shaped, 120 x 41 x 32 cm when operational, weighs between 1.5 and 2 kg (depending on materials used) and can be folded flat for easy transportation. It consists of several metal frames filled with fishing net, and has a

Aims: The mechanical properties of arteries play a major role in the regulation of blood pressure and cardiac performance. The effect of sympathetic stimulation on the mechanical properties of the proximal brachial artery was analysed in 18 healthy volunteers, nine young (25 +/- 2 years) and nine elderly (69 +/- 2 years). Methods: A non-invasive ultrasonic echo-tracking system for measurement of s

The European pine sawfly, Neodiprion sertifer (Geoffroy) (Hymenoptera: Diprionidae), is a widespread and economically important forest insect. The sex pheromone communication system of this species has been previously investigated in North America, Japan and Europe, with the acetate or propionate of the alcohol (2S,3S,7S)-3,7-dimethyl-2-pentadecanol (diprionol) shown to be the main pheromone compo