IN SEARCH OF IDEAL KNOTS

A concise introduction to the mathematical theory of knots is presented. Definitions of basic notionsare explained. Then, knots are considered as material objects and the question concerning their optimalconformations is posed. A numerical algorithm searching for the ideal knots is described. A few resultsobtained with its help are presented.Pozna

On non-measurable sets and invariant tori

The question: "How many different trajectories are there on a single invariant torus within the phase space of an integrable Hamiltonian system?" is posed. A rigorous answer to the question is found both for the rational and the irrational tori. The relevant notion of non-measurable sets is discussed.Comment: 8 pages, 1 figur

Unreasonable science

It is argued that most of the great discoveries in science, in particular in mathematics and physics, are from the point of view of the common sense unreasonable. A few examples of such discoveries are discussed, among them the Banach-Tarski paradoxical duplication of a sphere, the non-Euclidean geometry, the special theory of relativity and the quantum mechanics

Antimicrobial Photodynamic Inactivation: An Alternative for Group B <i>Streptococcus</i> Vaginal Colonization in a Murine Experimental Model

Background: Streptococcus agalactiae, referred to as Group B Streptococcus (GBS), is a prominent bacterium causing life-threatening neonatal infections. Although antibiotics are efficient against GBS, growing antibiotic resistance forces the search for alternative treatments and/or prevention approaches. Antimicrobial photodynamic inactivation (aPDI) appears to be a potent alternative non-antibiotic strategy against GBS. Methods: The effect of rose bengal aPDI on various GBS serotypes, Lactobacillus species, human eukaryotic cell lines and microbial vaginal flora composition was evaluated. Results: RB-mediated aPDI was evidenced to exert high bactericidal efficacy towards S. agalactiae in vitro (>4 log10 units of viability reduction for planktonic and >2 log10 units for multispecies biofilm culture) and in vivo (ca. 2 log10 units of viability reduction in mice vaginal GBS colonization model) in microbiological and metagenomic analyses. At the same time, RB-mediated aPDI was evidenced to be not mutagenic and safe for human vaginal cells, as well as capable of maintaining the balance and viability of vaginal microbial flora. Conclusions: aPDI can efficiently kill GBS and serve as an alternative approach against GBS vaginal colonization and/or infections