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Byline: J. Jankowski (1), H. Schluter (1), M. Tepel (1), C. Spieker (1), W. Zidek (1) Keywords: Key wordsaDiadenosine polyphosphates; Ca2+ ATPase Abstract: aDiadenosine tri-, tetra-, penta-, and hexaphosphate ([Ap.sub.3]A, [Ap.sub.4]A, [Ap.sub.5]A and [Ap.sub.6]A) have been described as having various effects on vascular tone depending on the number of phosphate groups. This study examined the effect of diadenosine polyphosphates on [Ca.sup.2+ ]ATPase activity. The activity of the enzyme was measured spectrophotometrically as the difference in hydrolysis of ATP in the presence and absence of [Ca.sup.2+ ]with various concentrations of ATP and diadenosine polyphosphates. The diadenosine polyphosphates increased the activity of the [Ca.sup.2+ ]ATPase. The effect tended to be stronger with [Ap.sub.5]A and [Ap.sub.6]A than with [Ap.sub.3]A and [Ap.sub.4]A in the order of potency: [Ap.sub.3]A[approximately equal to]A[P.sub.4]A&lt [Ap.sub.5]A[approximately equal to]A[P.sub.6]A. The stimulatory effect of diadenosine polyphosphates was not competitive with that of ATP, suggesting an allosteric activation of [Ca.sup.2+ ]ATPase by diadenosine polyphosphates. This effect may be physiologically relevant for limiting the increase in cytosolic free [Ca.sup.2+ ]concentration elicited by diadenosine polyphosphates by receptor activation and modulating [Ca.sup.2+ ]ATPase function under resting conditions. Author Affiliation: (1) Universitats-Klinik Marienhospital, Ruhr-Universitat Bochum, Holkeskampring 40, D-44625 Herne, Germany, DE Article note: Received: 24 January 1997 / Accepted: 9 May 1997

A collisional-radiative model of the discharge is presented with reference to spectroscopy diagnostics through line-intensity ratio of high-density diffusion-controlled discharge in helium-argon gas mixtures. The comparison with the corona model suggests the necessity of developing a collisional-radiative model.

A numerical fluid-plasma model of diffusion-controlled surface-wave sustained discharges in helium-argon gas mixtures is presented. The model provides results for the interrelated axial variations of the discharge characteristics such as wave number and wave space damping rate, power absorbed on average by electron, electro density and electro temperature, as well as ion densities, which are additional characteristics compared to discharges in pure gases.

Correlation of new multichannel seismic profiles across the upper Indus Fan and Murray Ridge with a dated industrial well on the Pakistan shelf demonstrates that ~40% of the Indus Fan predates the middle Miocene, and ~35% predates uplift of the Murray Ridge (early Miocene, ~22 Ma). The Arabian Sea, in addition to the Makran accretionary complex, was therefore an important repository of sediment from the Indus River system during the Paleogene. Channel and levee complexes are most pronounced after the early Miocene, coincident with an increase in sedimentation rates. Middle Eocene sandstones from Deep Sea Drilling Project Site 224 on the Owen Ridge yield K-feldspars whose Pb isotopic composition, measured by in situ ion microprobe methods, indicates an origin in, or north of, the Indus suture zone. This observation requires that India-Asia collision had occurred by this time and that an Indus River system, feeding material from the suture zone into the basin, was active soon after collision. Pleistocene provenance was similar to that during the Eocene, albeit with greater contribution from the Karakoram. A mass balance of the erosional record on land with deposition in the fan and associated basins suggests that only ~40% of the Neogene sediment in the fan is derived from the Indian plate. Keywords: Arabian Sea, Himalaya, Indian Ocean, Indus Fan, isotopes, provenance.

Investigates a guided wave propagation in inhomogeneous collisional magnetized plasmas. Reference to studies on the influence of transverse plasma-density nonuniformity and collisions; Focus on situations of moderate axial magnetic field strengths; Resonances in the radial field distribution.

Focuses on a program that monitored the prevalence of Salmonella infections in German egg production farms with different types of flock management. Recommendation of the development of a less costly routine monitoring program to detect Salmonella in samples taken from barns with layer flocks; Increase in the number of Salmonella isolations in samples taken from the floor pens.

Presents a fluid model of surface wave that produced discharges for diffusion controlled regimes, taking into account simultaneously nonlinear contributions from stepwise ionization and volume recombination. Effect of saturation of metastable densities with growing electron density; Charged particle continuity and energy balance equations.

Focuses on the error in the March 1st issue of 'Journal of Chemical Physics' which referred to the wrong page of the primary reference.

Presents several corrections to the article 'Predissociation of O[sub2] in the Β State,' from the 1988 issue of the 'Journal of Chemical Physics.'