o r due to a characteristic of the mechanism independent of this s e t of values.After extrapolating ( d~/ d i 2 )~" at l a r g e r angles, a s indicated by the dashed line in Fig. 3, the integrated c r o s s section for the production of quasi-Kr i s about 500 mb. It is a large part of the reaction c r o s s section (calculated value 870 mb), and this s e e m s to confirm the idea that the quasifission reactions occur instead of the complete-fusion reactions. One should remember, however, that the method used for the angular distribution is based on a hypothesis which i s reasonable but not entirely proved for angles f a r away from 553.More work-with more intense beams if possible-has to be done in o r d e r to get more detailed information on the features of the quasifission reactions induced by K r ions. Nevertheless we hope the indications we have obtained will stimulate theoretical work which i s now underway for understanding the reaction mechanism. In particular, the angular distribution should help in deciding among the various pict u r e s for the potential energy between the two nuclei which can be considered in order to explain the quasifission reactions."We thank N. Rowley for discussions and for reading the manuscript.Note added.*e have recently made angulardistribution measurements a t large angles. The maximum a t 65" has been confirmed but the descent above 80" is not as steep as the dashed curve on Fig. 3 Nuclear Shock Waves in Heavy-Ion CollisionsWerner Scheid, Hans Müller, and Walter Greiner k s t i t u t für Theoretische Physik der Universität Frankfurt, Frankfurt arn Main, Germany (Received 19 November 1973) It is shown that nuclear matter is compressed during the encounter of heavy ions. If the relative velocity of the nuclei is larger than the velocity of first sound in nuclear matter (compression sound for isospin T =O), nuclear shock waves occur. They lead to densities which are 3-5 times higher than the nuclear equilibrium density P,,, depending on the energy of the nuclei. The implications of this phenomenon are discussed.The possibility of compression of nuclear matt e r in nucleus-nucleus collisions in one of the most interesting aspects of heavy-ion physics. It has been discussed e a r l i e r in connection with the sudden nucleus-nucleus potentialsl and their energy d e p e n d e n~e ,~ which s e e m s to confirm the experimentally deduced heavy-ion potentials of the Yale g r o~p .~ These e a r l i e r considerations a r e valid a s long a s the relative heavy-ion velocity U , does not exceed the velocity of f i r s t sound in nuclear matter C,; i.e., for V , < C,. Here the f i r s t sound is an isospin T = 0 compression wave while the second sound describes an isospin T = 1 wave where a proton-neutron separation travels in constant nuclear matter density p, = p, + P , .~ In o r d e r to study local compression effects for

No abstract

Most of the interindividual variations in plasma levels of lipoprotein(a) [Lp(a)] can be attributed to sequence differences linked to the apolipoprotein(a) [apo(a)] locus. Plasma levels of Lp(a) tend to be inversely related to the number of kringle 4 (K4)-encoding sequences in the apo(a) gene, but there are several exceptions to this general trend. Other aspects of the apo(a) gene, in addition to the number of K4 repeats, affect plasma levels of Lp(a). To identify sequences in the apo(a) gene that contribute to plasma Lp(a) levels, we characterized the relationship between a length polymorphism [(TTTTA)n] located 1.3 kb 5' of the first exon of the apo(a) gene, the number of K4 repeats in the gene, and the plasma levels of Lp(a). There was significant linkage disequilibrium between the number of TTTTA repeats and the number of K4 repeats. All of the apo(a) alleles with 11 TTTTA repeats contained fewer than 24 K4 repeats and were paradoxically associated with low plasma Lp(a) levels (< or = mg/dl). To determine whether this association was due to the effect of the 11 TTTTA copies on apo(a) gene transcription, we measured the ability of fragments containing 11 or eight TTTTA repeats to promote transcription when introduced into cultured human hepatocarcinoma cells. No difference was found in the transcriptional activity of the two fragments. The TTTTA repeat constitutes the first sequence polymorphism at the apo(a) locus, other than the number of K4 repeats, which is associated with plasma concentrations of Lp(a).

No abstract

A general expression is given for the change in free energy when a charge tunnels through a junction in a one-dimensional array of N metallic islands with arbitrary capacitances and arbitrary background charges. This is used to obtain expressions for the ͑average͒ threshold voltage of the Coulomb blockade for a few characteristic geometries. We find that including random background charges has a large effect on the N dependence of the threshold voltage: In an array with identical junction capacitances C and gate capacitances C g , the threshold voltage, averaged over the background charge, is proportional to N a , where a crosses over from 1 2 to 1 when N becomes larger than 2.5ͱC/C g .

latent trait, Rasch model, thresholds, rating scales, continuous responses, ceiling and floor effects, normal distribution,

Two hours after cessation of exercise the neutrophils increased stronger after AN-TS than after SMT (P < 0.01). The peak in the number of premacrophages occurred earlier after SMT (15 min post; P < 0.01 to Co-Day) than after AN-TS (2 h post; P < 0.05 to Co-Day). IL-6 was elevated at 15 min and 2 h after AN-TS (P < 0.01 to SMT and Co-Day) but only slightly 2 h after SMT (P < 0.01 to Co-Day). There were no significant changes in IL-8. CRP was the only elevated parameter 24 h postexercise exclusively after AN-TS (P < 0.05 to Co-Day). CONCLUSIONS Repeated short anaerobic bouts of cycling lead to an acute phase response, which is more pronounced than after a single bout. Athletes should take care in performing such training sessions several times a week because signs of inflammation are detectable even 24 h after cessation of exercise.

The influence of both geometric and offset charge disorder of two-dimensional quantum dot arrays ͑also known as network tunnel junctions͒ on their Coulomb blockade voltage V b is studied using extensive Monte-Carlo simulations. A general increase of V b with increasing disorder is confirmed, but an exception to the rule is found for intermediate degrees of offset charge disorder. Detailed studies of the V b distribution reveal a stability of its minimal value against geometric disorder, whereas this figure is considerably increased for high offset charge disorder. Implications of our results for single electron device design are discussed.