Large-deviation inequalities for parameter estimators in stochastic systems

Translated from Kibernetika i Sistemnyi Analiz, No. 2, pp. 95–112, March–April, 1994.     

Platelet aggregation inhibiting and anticoagulant effects of oligoamines, XX: 4,4',4'-(1,3,5)-benzene-tris-sydnone imines

The synthesis of ten tris-sydnone imine derivatives, unknown up to now, is described. All compounds are alkyl or arylalkyl substituted in 3-position of the sydnone imine. The most powerful agent was the 3-propyl derivative 6c. It inhibits the aggregation of human platelets induced by collagen in a concentration of 1 mumol/L half maximally. Its N-ethoxycarbonyl derivative 7c, which was designed as a prodrug, showed only small antithrombotic effects in rats. The reason for this low degree of activity is discussed.     

Modified surface-active monomers for adhesive bonding to dentin

PMGDM, a PMDM-type adhesive monomer, was synthesized from pyromellitic dianhydride and glycerol dimethacrylate. Only the para isomer of PMDM, a solid, is used in dental adhesives. The adhesive monomer PMGDM is a liquid and consists of a mixture of para- and meta isomers. This study shows that PMGDM has several advantages over PMDM. For example, the adhesive can be applied at a greater thickness, and additives and/or additional initiators for improved curing can be incorporated. Use of the liquid monomer PMGDM also provided a convenient means of varying the thickness of the adhesive layer between dentin and composite. The adhesive bonds were tested in both shear and tensile modes. PMDM was used as the control. The reliability of the bonds, as judged from the Weibull modulus and Weibull characteristic strength, was improved by (1) use of more concentrated solutions of PMGDM adhesive, (2) use of an adhesive thickness of about 25 microns, and (3) modification of PMGDM with a diluent monomer which is expected to enhance the degree of cure and/or the dentin-wetting properties of the adhesive resin.