The extracellular Opacity Factor elaborated by a strain of group A streptococcus M type 2 was purified by ammonium sulphate precipitation, DEAE-cellulose and hydroxylapatite column chromatography and Sephadex G-200 gel filtration. Gel filtration experiments indicated that the Opacity Factor is consituted of high molecular weight proteins or protein aggregates which appear to dissociate into sub...

Software transactional memory (STM) provides programmers with a high-level programming abstraction for synchronization of parallel processes, allowing blocks of codes that execute in an interleaved manner to be treated as an atomic block. This atomicity property is captured by a correctness criterion called opacity. Opacity relates histories of a sequential atomic specification with that of STM...

BACKGROUND Apo A-I deficiency clinically shows low serum levels of HDL cholesterol and corneal opacity at a young age. Histopathological evaluations of affected corneas are not enough, and the mechanism of corneal opacity is still unclear. CASE PRESENTATION A 61-year-old woman suffered from blurred vision with a corneal opacity. She had significantly reduced serum levels of high-density lipop...

Visual Determination of the Opacity of Emissions from Stationary Sources (Method 9) is a reference method established by U.S. Environmental Protection Agency (EPA) to quantify plume opacity. However, Method 9 relies on observations from humans, which introduces subjectivity. In addition, it is expensive to teach and certify personnel to evaluate plume opacity on a semiannual basis. In this stud...

Purpose This paper aims to identify what are the moderating factors affecting relationship between firms’ adoption of international financial and reporting standards (IFRS) firm’s opacity. Design/methodology/approach study uses meta-analysis methodology from Hunter et al. (1982) find if mere IFRS reduces opacity a meta-regression Stanley Jarrell (1989) that may influence this relationship. Find...

In this paper, we are interested in the validation of opacity where opacity means the impossibility for an attacker to retrieve the value of a secret in a system of interest. Roughly speaking, ensuring opacity provides confidentiality of a secret on the system that must not leak to an attacker. More specifically, we study how we can verify and enforce, at system runtime, several levels of opaci...