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Motivated from reasoning in rough set theory, we have introduced and studied proof-theoretic properties of a class of logics L(T,I) in the first part of this article. These are logics with models based on 'dynamic I spaces', which are finite sequences of Kripke I frames with a common domain, I being any of the normal modal systems K, K4, T, B, S4, KTB, KB4, S5. This article presents the second part of the study on L(T,I), where we focus on decidability issues. [ABSTRACT FROM AUTHOR]

While virulence properties of C andida albicans, the most commonly isolated human fungal pathogen, are controlled by transcriptional and post-translational mechanisms, considerably little is known about the role of post-transcriptional, and particularly translational, mechanisms. We demonstrate that UME6, a key filament-specific transcriptional regulator whose expression level is sufficient to determine C . albicans morphology and promote virulence, has one of the longest 5′ untranslated regions ( UTRs) identified in fungi to date, which is predicted to form a complex and extremely stable secondary structure. The 5′ UTR inhibits the ability of UME6, when expressed at constitutive high levels, to drive complete hyphal growth, but does not cause a reduction in UME6 transcript. Deletion of the 5′ UTR increases C . albicans filamentation under a variety of conditions but does not affect UME6 transcript level or induction kinetics. We show that the 5′ UTR functions to inhibit Ume6 protein expression under several filament-inducing conditions and specifically reduces association of the UME6 transcript with polysomes. Overall, our findings suggest that translational efficiency mechanisms, known to regulate diverse biological processes in bacterial and viral pathogens as well as higher eukaryotes, have evolved to inhibit and fine-tune morphogenesis, a key virulence trait of many human fungal pathogens. [ABSTRACT FROM AUTHOR]

A new scheme of knowledge encoding in a fuzzy multilayer perceptron (MLP) using rough set-theoretic concepts is described. Crude domain knowledge is extracted from the data set in the form of rules. The syntax of these rules automatically determines the appropriate number of hidden nodes while the dependency factors are used in the initial weight encoding. The network is then refined during training. Results on classification of speech and synthetic data demonstrate the superiority of the system over the fuzzy and conventional versions of the MLP (involving no initial knowledge). Index Terms - Fuzzy MLP, knowledge-based networks, network design, pattern recognition, rough sets, rule generation, soft computing, speech recognition.

The objective of this paper is to examine the activities consumers engage in malls, whether the mall culture is gradually gaining acceptance among consumers and the reasons for such acceptance. Modern organized retail has forayed into Kolkata, as is evident in supermarkets and multi-storeyed malls that offer shopping, entertainment and provision for eating under one roof. Retailers and mall managers should be aware of the benefits perceived by consumers at malls, whether consumers are shifting their preference from traditional zone-based buying to shopping in malls and the factors responsible for such change, in order to optimally position themselves. The study finds that primarily in the malls for shopping, consumers prefer eating at food-courts, window shopping and entertainment in the form of movies at multiplexes or video game parlors. They also attend events, promotions, competitions and product launches that are organized in the malls and spend their leisure time with family and friends. Over the period July 2004 to March 2007, the mall culture has gained acceptance and consumers are repeating their visits for successive purchases marked by the increase of regular users at malls. In malls, consumers prefer the air-conditioned environment, availability of several product categories under one roof, quality of service, car parking facilities, ambience, convenience of shopping and the confidence that the store-owner is not cheating. Such lifestyle factors along with the status symbol of being in malls, supplemented with a greater disposable income are the chief reasons that prompt them to the malls. [ABSTRACT FROM AUTHOR]

Candida albicans, the major human fungal pathogen, undergoes a reversible morphological transition from single yeast cells to pseudohyphal and hyphal filaments (elongated cells attached end-to-end). Because typical Calbicans infections contain a mixture of these morphologies it has, for many years, been difficult to assess the relative contribution of each form to virulence. In addition, the regulatory mechanisms that determine growth in pseudohyphal and hyphal morphologies are largely unknown. To address these questions we have generated a C. albicans strain that can be genetically manipulated to grow completely in the hyphal form under non-filament-inducing conditions in vitro. This was achieved by inducing high-level constitutive expression of UME6, a recently identified filament-specific transcriptional regulator of C. albicans hyphal extension. We show that high-level UME6 expression significantly increases hyphal formation and promotes virulence in a mouse model of systemic candidiasis. Our results strongly suggest that shifting the morphology of a Calbicans population toward the hyphal form, and/or increasing hyphalspecific gene expression, during the course of infection is sufficient to improve virulence potential. We also demonstrate that lower levels of UME6 expression specify growth largely in the pseudohyphal form and that increasing UME6 levels is sufficient to cause cells to gradually shift from pseudohyphal to hyphal morphology. In addition, we show that UME6 levels differentially induce the expression of several known filament-specific transcripts. These findings suggest that a common transcriptional regulatory mechanism functions to specify both pseudohyphal and hyphal morphologies in a dosage-dependent manner. [ABSTRACT FROM AUTHOR]

A dialogue is an 'activity' by a pair of agents to arrive at some kind of understanding over a concept/belief/piece of information etc. represented by a subset (the extension) in some universe of discourse. The universe is partitioned into two different sets of granules (equivalence classes) representing the perceptions of the agents. So, there are two approximation spaces at the beginning. A third approximation space arises out of superimposition of the two partitions. A dialogue is a finite process of gradual enhancement of the two base subsets of the agents, in their 'common' approximation space. Through this process, various kinds of overlap may emerge between the two final subsets. A first introduction of the idea of a dialogue in rough context was made in [6]. This paper further develops the notion and focusses upon the study of the above-mentioned overlaps in a systematic manner. Given two sets A and B in an approximation space, there are nine possible inclusion relations among the sets lo(A),A, up(A), lo(B),B and up(B) where lo and up denote the lower and upper approximation operators respectively. There are five resulting equivalence classes and the quotient set forms a lattice by implication ordering. That is, of the nine relations, only five are independent and they form an implication or entailment lattice. Starting with this basic lattice other implication lattices are formed. Relationship of these lattices with the various overlap conditions between the final pair of sets arrived at after a dialogue is studied. Finally, examples are given, one of which relates dialogues in rough context with rough belief revision [3] – in a line similar to the approach of [5]. [ABSTRACT FROM AUTHOR]

Pawlak had proposed the notion of rough truth in 1987 [16]. The article takes a fresh look at this "soft" truth, and presents a formal system L_R, that is shown to be sound and complete with respect to a semantics determined by this notion. L_R is based on the modal logic S5. Notable is the rough consequence relation defining L_R (a first version introduced in [9]), and rough consistency (also introduced in [9]), used to prove the completeness result. The former is defined in order to be able to derive roughly true propositions from roughly true premisses in an information system. The motivation for the latter stems from the observation that a proposition and its negation may well be roughly true together. A characterization of L_R-consequence shows that the paraconsistent discussive logic J of Jaśkowski is equivalent to L_R. So, L_R, developed from a totally independent angle, viz. that of rough set theory, gives an alternative formulation to this well-studied logic. It is further observed that pre-rough logic [3] and 3-valued Łukasiewicz logic are embeddable into L_R. [ABSTRACT FROM AUTHOR]