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It will be our purpose in this article to develop a few considerations on the way in which the teaching of mathematics and more generally the teaching of science is dealt with in the proposals for reform of the upper secondary school, on the problems arising as a consequence thereof, and on the debate that scientific associations have been carrying out on this matter. Our point of departure will be the prospectus (Appendix 1) which presents the references relevant to mathematics and sciences in the various drafts.

We report that the mitotic inhibitor, vinblastin (VLB), is highly toxic to the malarial parasite, Plasmodium falciparum. In cultures in vitro growth is inhibited by 50% at a VLB level of about 28 nM, and totally abolished at a level of 100 nM. By tests on synchronized cultures we have found that the effect of VLB takes place at the trophozoite stage. Colcemid also inhibits schizogony with somewhat different kinetics. By mutagenesis with nitrosoguanidine followed by VLB selection we have isolated a VLB-resistant mutant which exhibits cross-resistance to vincristine. These data suggest a critical role of microtubules in the asexual schizogonic cycle of P. falciparum.

We report that the mitotic inhibitor, vinblastin (VLB), is highly toxic to the malarial parasite, Plasmodium falciparum. In cultures in vitro growth is inhibited by 50% at a VLB level of about 28 nM, and totally abolished at a level of 100 nM. By tests on synchronized cultures we have found that the effect of VLB takes place at the trophozoite stage. Colcemid also inhibits schizogony with somewhat different kinetics. By mutagenesis with nitrosoguanidine followed by VLB selection we have isolated a VLB‐resistant mutant which exhibits cross‐resistance to vincristine. These data suggest a critical role of microtubules in the asexual schizogonic cycle of P. falciparum.

In this paper, we deal with the problem of active damping of vibrations of a continuous viscoelastic structure, and a general method of computation of the control system is developed. We define a mechanical model for this structure, the sources of perturbing vibrations, the control system, and different absorption criteria. The problem is set in an infinite dimension space, and an approximation problem is derived in n dimension spaces. Two methods of resolution are proposed for this approximation problem, and the solutions are compared. An example is given for the case of flexural vibrations in beams. Numerical results simulating the behavior of flexural vibrations in a rectangular plate, which is simply supported along the whole boundary, are presented for three different absorption criteria, thus permitting a quick evaluation of the comparative effectiveness of the chosen criteria.