The contribution of different membrane constituents to the bloodgroup P1 activity of human erythrocytes was investigated. Pronase digestion of native red cell stroma or partition between butanol and water had no serologically detectable effect, whereas pronase‐treatment of previously butanol‐extracted membranes liberated virtually all blood‐group P1 determinants from the ghosts. On Laemmli gels, all P1 activity was found in the band 4.5 region. Thus it is concluded that, in addition to the well‐documented P1 glycolipid, also membrane glycoproteins are carriers of blood‐group P1 determinants.

The dependence of optical, electronic and thermal penetration zones on the thickness of nanoscale layers grown on silicon wafers is reported. Tetrahedral amorphous carbon (ta-C) and amorphous carbon nitride (a-C x N y ) films were prepared by inverse pulsed laser deposition (IPLD). Single-pulse modification thresholds for femtosecond laser processing proved to be dependent on the actual film thickness below 60 nm for ta-C and 90 nm for a-C x N y . The modification behaviour was governed by multiphoton processes. An effective penetration depth of the laser radiation in a-C x N y was of ca. 110 nm in accordance with two-photon absorption. Both the emergence length of ballistic hot electrons and the heat diffusion length are negligible in these thin film materials. The lower bulk value of the threshold fluence of the a-C x N y films as compared to ta-C is mainly controlled by optical contributions due to nitrogen-related defects.

No abstract

No abstract

No abstract