A system of state-dependent delay differential equation modelling forest growth I: semiflow properties

In this article we investigate the semiflow properties of a class of state-dependent delay differential equations which is motivated by some models describing the dynamics of the number of adult trees in forests. We investigate the existence and uniqueness of a semiflow in the space of Lipschitz and $C^1$ weighted functions. We obtain a blow-up result when the time approaches the maximal time of existence. We conclude the paper with an application of a spatially structured forest model

UNDERSTANDING THE SIMILARITY AND DIVERISTY OF THE ACCESSORY GENE REGULATOR QUORUM SENSING SYSTEMS IN THE GENUS CLOSTRIDIUM

The Accessory Gene Regulator (Agr) quorum sensing system is a cell-cell communication system that is involved in regulating various bacterial processes such as toxin production, antibiotic production, biofilm formation, and other biomolecules. Despite the importance of the Agr system to Clostridia, the similarity and diversity of the system have been overshadowed by phylum-wide investigations of individual Agr components. To determine the variability of the Agr system within and between Clostridium species, we compared the sequences of its components within and between species using bioinformatics and phylogenetic tools. Putative Agr operons were found in over 50 Clostridia species, including undescribed components in some of the species with known operons. The Agr components were mostly similar within species and in some cases, differed between other Clostridial species. Conserved residues of unknown function were also found. The prevalence of the Agr system and the identification of common motifs in its components opens up therapeutic targets to be harnessed for the development of non-antibiotic and anti-virulence therapies for pathogenic Clostridial infections

Risk communication as an operation meant to produce and share audiences

In this article, Luhmann's system theory is used as a theoretical framework for analysing the way risk communicators view their social functions. Narrated experiences from risk communicators in practice facilitate an understanding of risk communication as both an external irritation to society and part of the mass communication system. They also aid in clarifying how perceptions of audiences are reflected in the risk-communication strategies. The analysis is based on qualitative data collected from in-depth interviews conducted with 22 risk communicators (scientific professionals, spokespeople and journalists) in Israel. Thematic areas reflected in interviewees' reported strategies embody their perception of audiences. Those themes include: the reduction of complexities; coding and sorting of information; autopoiesis (realisation/non-realisation of the risk); rationality; inherent paradoxes; and schema formation. In sum, the findings suggest that risk communicators play a major role in defining, creating and producing audiences for the mass communication system

Internet Browser Configuration for Presentations

The increased use of the Internet and the World Wide Web in presentations requires that techniques must be developed to ensure service standards of performance, consistency, flexibility, availability, and reliability of the presentation. Since operation of the network and the visited web site is often outside of the control of the presenter, other approaches must be developed. This paper looks at the configuration and use of a web browser to address these issues

Have the Transformational Information Technologies Really Transformed the Academia?

The Internet and the World Wide Web are often referred to as transformational information technologies (Jarvenpaa and Ives, 1996). With the advent and rapid growth of these technologies, the business landscape is being redrawn through the shrinking of space and time, and exploding global competition. While a number of studies have been initiated in recent years to research into different facets of electronic commerce (EC), very few studies have been undertaken to examine the impact of these transformational information technologies on the academia who are among the early users