Decision Representation Language (DRL) and Its Support Environment

In this report, I describe a language, called Decision Representation Language (DRL), for representing the qualitative aspects of decision making processes such as the alternatives being evaluated, goals to satisfy, and the arguments evaluating the alternatives. Once a decision process is represented in this language, the system can provide a set of services that support people making the decision. These services, together with the interface such as the object and the different presentation formats, form the support environment for using the language. I describe the services that have been so far identified to be useful — the managements of dependency, plausibility, viewpoints, and precedents. I also discuss how this work on DRL is related to other studies on decision making.MIT Artificial Intelligence Laborator

IDEME: A DBMS of Methods

In this paper, an intelligent database management system (DBMS) called IDEME is presented. IDEME is a program that takes as input a task specification and finds a set of methods potentially relevant to solving that task. It does so by matching the task specification to the methods in its database at multiple levels of abstraction. After isolating potentially useful methods, IDEME ranks them by how relevant they might be to the task. From the most relevant method, it checks if its operational demands, i.e. those conditions that have to be satisfied for the method to be applicable, are satisfied by the present task. If so, it presents the algorithm of the method relativized to the present task; otherwise, it goes on to the next method. In this paper, the focus will be on the representation scheme that is used by IDEME to represent methods as well as tasks.MIT Artificial Intelligence Laborator

The Effect of Self Identity and Social Identity on Technology Acceptance

While the effect of social factors on information technology (IT) acceptance behavior has been recognized as an important issue, only a few studies examined this topic in the context of the technology acceptance model. In this study, we incorporate two social factors, self identity and social identity, in the model and address their impacts on IT acceptance decision. An empirical study investigating the impact these social factors have on the acceptance of a web-based class support system is in progress. Upon completion of this study, we expect to provide further understanding on the role of social influence on individual technology acceptance decisions

What\u27s in Design Rationale?

A few representations have been used for capturing design rationale. To understand their scope and adequacy, we need to know how to evaluate them. In this article, we develop a framework for evaluating the expressive adequacy of design rationale representations. This framework is built by progressively differentiating the elements of design rationale that, when made explicit, support an increasing number of the design tasks. Using this framework, we present and assess DRL (Decision Representation Language), a language for representing rationales that we believe is the most expressive of the existing representations. We also use the framework to assess the expressiveness of other design rationale representations and compare them to DRL. We conclude by pointing out the need for articulating other dimensions along which to evaluate design rationale representations

Indole is an inter-species biofilm signal mediated by SdiA

<p>Abstract</p> <p>Background</p> <p>As a stationary phase signal, indole is secreted in large quantities into rich medium by <it>Escherichia coli </it>and has been shown to control several genes (e.g., <it>astD</it>, <it>tnaB</it>, <it>gabT</it>), multi-drug exporters, and the pathogenicity island of <it>E. coli</it>; however, its impact on biofilm formation has not been well-studied.</p> <p>Results</p> <p>Through a series of global transcriptome analyses, confocal microscopy, isogenic mutants, and dual-species biofilms, we show here that indole is a non-toxic signal that controls <it>E. coli </it>biofilms by repressing motility, inducing the sensor of the quorum sensing signal autoinducer-1 (SdiA), and influencing acid resistance (e.g., <it>hdeABD, gadABCEX</it>). Isogenic mutants showed these associated proteins are directly related to biofilm formation (e.g., the <it>sdiA </it>mutation increased biofilm formation 50-fold), and SdiA-mediated transcription was shown to be influenced by indole. The reduction in motility due to indole addition results in the biofilm architecture changing from scattered towers to flat colonies. Additionally, there are 12-fold more <it>E. coli </it>cells in dual-species biofilms grown in the presence of <it>Pseudomonas </it>cells engineered to express toluene <it>o-</it>monooxygenase (TOM, which converts indole to an insoluble indigoid) than in biofilms with pseudomonads that do not express TOM due to a 22-fold reduction in extracellular indole. Also, indole stimulates biofilm formation in pseudomonads. Further evidence that the indole effects are mediated by SdiA and homoserine lactone quorum sensing is that the addition of <it>N</it>-butyryl-, <it>N</it>-hexanoyl-, and <it>N</it>-octanoyl-<it>L</it>-homoserine lactones repress <it>E. coli </it>biofilm formation in the wild-type strain but not with the <it>sdiA </it>mutant.</p> <p>Conclusion</p> <p>Indole is an interspecies signal that decreases <it>E. coli </it>biofilms through SdiA and increases those of pseudomonads. Indole may be manipulated to control biofilm formation by oxygenases of bacteria that do not synthesize it in a dual-species biofilm. Furthermore, <it>E. coli </it>changes its biofilm in response to signals it cannot synthesize (homoserine lactones), and pseudomonads respond to signals they do not synthesize (indole).</p

Indole and 3-indolylacetonitrile inhibit spore maturation in Paenibacillus alvei

<p>Abstract</p> <p>Background</p> <p>Bacteria use diverse signaling molecules to ensure the survival of the species in environmental niches. A variety of both Gram-positive and Gram-negative bacteria produce large quantities of indole that functions as an intercellular signal controlling diverse aspects of bacterial physiology.</p> <p>Results</p> <p>In this study, we sought a novel role of indole in a Gram-positive bacteria <it>Paenibacillus alvei </it>that can produce extracellular indole at a concentration of up to 300 μM in the stationary phase in Luria-Bertani medium. Unlike previous studies, our data show that the production of indole in <it>P. alvei </it>is strictly controlled by catabolite repression since the addition of glucose and glycerol completely turns off the indole production. The addition of exogenous indole markedly inhibits the heat resistance of <it>P. alvei </it>without affecting cell growth. Observation of cell morphology with electron microscopy shows that indole inhibits the development of spore coats and cortex in <it>P. alvei</it>. As a result of the immature spore formation of <it>P. alvei</it>, indole also decreases <it>P. alvei </it>survival when exposed to antibiotics, low pH, and ethanol. Additionally, indole derivatives also influence the heat resistance; for example, a plant auxin, 3-indolylacetonitrile dramatically (2900-fold) decreased the heat resistance of <it>P. alvei</it>, while another auxin 3-indoleacetic acid had a less significant influence on the heat resistance of <it>P. alvei</it>.</p> <p>Conclusions</p> <p>Together, our results demonstrate that indole and plant auxin 3-indolylacetonitrile inhibit spore maturation of <it>P. alvei </it>and that 3-indolylacetonitrile presents an opportunity for the control of heat and antimicrobial resistant spores of Gram-positive bacteria.</p

Antibiofilm activity of carotenoid crocetin against Staphylococcal strains

Staphylococcus aureus and Staphylococcus epidermidis stand as notorious threats to human beings owing to the myriad of infections they cause. The bacteria readily form biofilms that help in withstanding the effects of antibiotics and the immune system. Intending to combat the biofilm formation and reduce the virulence of the pathogens, we investigated the effects of carotenoids, crocetin, and crocin, on four Staphylococcal strains. Crocetin was found to be the most effective as it diminished the biofilm formation of S. aureus ATCC 6538 significantly at 50 µg/mL without exhibiting bactericidal effect (MIC &gt;800 µg/mL) and also inhibited the formation of biofilm by MSSA 25923 and S. epidermidis at a concentration as low as 2 µg/mL, and that by methicillin-resistant S. aureus MW2 at 100 µg/mL. It displayed minimal to no antibiofilm efficacy on the Gram-negative strains Escherichia coli O157:H7 and Pseudomonas aeruginosa as well as a fungal strain of Candida albicans. It could also curb the formation of fibrils, which partly contributes to the biofilm formation in S. epidermidis. Additionally, the ADME analysis of crocetin proclaims how relatively non-toxic the chemical is. Also, crocetin displayed synergistic antibiofilm characteristics in combination with tobramycin. The presence of a polyene chain with carboxylic acid groups at its ends is hypothesized to contribute to the strong antibiofilm characteristics of crocetin. These findings suggest that using apocarotenoids, particularly crocetin might help curb the biofilm formation by S. aureus and S. epidermidis

A Transdisciplinary Approach to Construct Search and Integration

Human behaviors play a leading role in many critical areas including the adoption of information systems, prevention of many diseases, and educational achievement. There has been explosive growth of research in the behavioral sciences during the past decade. Behavioral science researchers are now recognizing that due to this ever expanding volume of research it is impossible to find and incorporate all appropriate inter-related disciplinary knowledge. Unfortunately, due to inconsistent language and construct proliferation across disciplines, this excellent but disconnected research has not been utilized fully or effectively to address problems of human health or other areas. This paper introduces a newly developed, cutting edge technology, the Inter-Nomological Network (INN) which for the first time provides an integrating tool to behavioral scientists so they may effectively build upon prior research. We expect INN to provide the first step in moving the behavioral sciences into an era of integrated science. INN is based on Latent Semantic Analysis (LSA), a theory of language use with associated automatic computerized text analysis capabilities