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J Papavassiliou

Publications and source records attributed to J Papavassiliou.

At least 19 recordsLinked to original sources

Novel type of CPT violation for correlated Einstein-Podolsky-Rosen states of neutral mesons.

We discuss modifications to the concept of an "antiparticle," induced by a breakdown of the CPT symmetry at a fundamental level, realized within an extended class of quantum gravity models. The resulting loss of particle-antiparticle identity in the neutral-meson system induces a breaking of the Einstein-Podolsky-Rosen correlation imposed by Bose statistics. This is parametrized by a complex parameter associated with the contamination by the "wrong symmetry" state. The physical consequences are studied, and novel observables of CPT violation in phi factories are proposed.

Journal Article↗

Observability of the neutrino charge radius.

It is shown that the probe-independent charge radius of the neutrino is a physical observable; as such, it may be extracted from experiment, at least in principle. This is accomplished by expressing a set of experimental nu(mu)-e cross sections in terms of the finite charge radius and two additional gauge- and renormalization-group-invariant quantities, corresponding to the electroweak effective charge and mixing angle.

Journal Article↗

The pinch technique at two loops

It is shown that the fundamental properties of gauge independence, gauge invariance, unitarity, and analyticity of the S matrix lead to the unambiguous generalization of the pinch technique algorithm to two loops.

Journal Article↗

Differences in adherence to buccal epithelial cells, in phagocytosis and in killing by neutrophils between human and non-human strains of Candida albicans.

The adherence of strains of Candida albicans to buccal epithelial cells as well as the phagocytosis of these organisms by human polymorphonuclear leucocytes (PMNL) was studied. The strains of C. albicans were obtained from patients' urine. from bird faeces and from soil. The strains of C. albicans obtained from patients and the environment displayed greater adhering ability (23.8 +/- 6.4 and 27.5 +/- 5.2 respectively) than the avian strains (14.4 +/- 2.2) (P < 0.01). Strains obtained from the environment were resistant to phagocytosis (81.6 +/- 0.2 organisms ingested per 200 PMNL) and killing (8.4 +/- 2.6%) by PMNL as compared to human and avian strains (P < 0.01). These observations indicate that environmental strains of C. albicans may be more virulent for human beings.

Animals↗

[Evaluation of the efficacy of antimicrobial drugs in ophthalmic solutions].

The antimicrobial efficacy of preservatives in ophthalmic solutions was tested. Five strains were used as challenge organisms. They represented bacteria, yeasts and molds. Sixty per cent of the ophthalmic solutions showed a good preservation against S. aureus ATCC 6538, according to the standards and in 40% of cases, the bacteria disappeared on the second week. Against E. coli ATCC 8739, 90% of the samples were well preserved and in 10% the bacteria disappeared by the second week. Against Ps. aeruginosa ATCC 9027, C. Albicans ATCC 10231 and Asp. niger ATCC 16404, the ophthalmic solutions showed a 100% preservation. The majority of the products showed a satisfactory preservation. They contained declared preservatives and sometimes combinations of two antimicrobial agents.

Animals↗