Search

We present the first provably-secure three-party password-only authenticated key exchange (PAKE) protocol that can run in only two communication rounds. Our protocol is generic in the sense that it can be constructed from any two-party PAKE protocol. The protocol is proven secure in a variant of the widely-accepted model of Bellare, Pointcheval and Rogaway (2000) without any idealized assumptions on the cryptographic primitives used. We also investigate the security of the two-round, three-party PAKE protocol of Wang, Hu and Li (2010) and demonstrate that this protocol cannot achieve implicit key authentication in the presence of an active adversary. [ABSTRACT FROM AUTHOR]

Objective: This study investigated the prevalence of infections with human papillomavirus, Chlamydia trachomatis, Ureaplasma urealyticum, Mycoplasma hominis, and Mycoplasma genitalium in the semen of Korean infertile couples and their associations with sperm quality. Methods: Semen specimens were collected from 400 men who underwent a fertility evaluation. Infection with above five pathogens was assessed in each specimen. Sperm quality was compared in the pathogen-infected group and the non-infected group. Results: The infection rates of human papillomavirus, C. trachomatis, U. urealyticum, M. hominis, and M. genitalium in the study subjects were 1.57%, 0.79%, 16.80%, 4.46%, and 1.31%, respectively. The rate of morphological normality in the U. urealyticum-infected group was significantly lower than in those not infected with U. urealyticum. In a subgroup analysis of normozoospermic samples, the semen volume and the total sperm count in the pathogen-infected group were significantly lower than in the non-infected group. Conclusion: Our results suggest that infection with U. urealyticum alone and any of the five sexually transmitted infections are likely to affect sperm morphology and semen volume, respectively. [ABSTRACT FROM AUTHOR]