Abstract: We discuss the development of an environment for formal knowledge engineering. The Sigma system is an advance over previously developed systems in that it integrates a number of modern ontology development tools, which has motivated a number of research issues. Primary components include an ontology browsing and editing environment, a first order logic inference system and a natural l...

We determined that the putative upstream promoter of the long transcript (P1) of ompA, the gene encoding the major outer membrane protein of Chlamydia trachomatis L2, is recognized in vitro by the major sigma factor of chlamydiae, sigma 66. We found no evidence that the putative downstream promoter of the short ompA transcript (P1) is functional in vitro. RNase protection of guanylyltransferase...

The sigB operon of Bacillus subtilis encodes sigma B and three additional open reading frames (orfV, orfW, and orfX). Having previously mapped several mutations that alter the induction pattern of a sigma B-dependent promoter (ctc) to regions of cloned B. subtilis DNA which contain these three open reading frames, we directly tested the regulatory potential of orfV, orfW, and orfX by creating n...

The operon encoding the general stress transcription factor sigma(B) and two proteins of its regulatory network, RsbV and RsbW, was cloned from the gram-positive bacterium Bacillus anthracis by PCR amplification of chromosomal DNA with degenerate primers, by inverse PCR, and by direct cloning. The gene cluster was very similar to the Bacillus subtilis sigB operon both in the primary sequences o...

Memory consolidation is stabilized and even enhanced by sleep (and particularly by 12-15 Hz sleep spindles in NREM stage 2 sleep) in healthy children but it is unclear what happens to these processes when sleep is disturbed by obstructive sleep disordered breathing. This cross-sectional study investigates differences in declarative memory consolidation among children with primary snoring (PS) a...

there has been considerable number of papers published related to six sigma applications in manufacturing and service organizations. however, very few studies are done on reviewing the literature of six sigma in all the areas including manufacturing, construction, education, financial service, bpos and healthcare etc. considering the contribution of six sigma in recent time, a more comprehensiv...

There has been considerable number of papers published related to Six Sigma applications in manufacturing and service organizations. However, very few studies are done on reviewing the literature of Six Sigma in all the areas including manufacturing, construction, education, financial service, BPOs and healthcare etc. Considering the contribution of Six Sigma in recent time, a more comprehens...

This paper presents a comparative analysis between two current control strategies, constant source power and generalized Fryze current, used in Active Power Filter (APF) applications having three different modulation methods. The Hysteresis Band (HB) and first-order Delta-Sigma Modulation (DSM) as well as the second-order DSM is applied. The power section of the active power filter is viewed as...

Let $G$ be a finite group. The automorphism $sigma$ of a group $G$ is said to be an absolute central automorphism, if for all $xin G$, $x^{-1}x^{sigma}in L(G)$, where $L(G)$ be the absolute centre of $G$. In this paper, we study  some properties of absolute central automorphisms of a given finite $p$-group.