Finding rule groups to classify high dimensional gene expression datasets

Microarray data provides quantitative information about the transcription profile of cells. To analyse microarray datasets, methodology of machine learning has increasingly attracted bioinformatics researchers. Some approaches of machine learning are widely used to classify and mine biological datasets. However, many gene expression datasets are extremely high dimensionality, traditional machine learning methods cannot be applied effectively and efficiently. This paper proposes a robust algorithm to find out rule groups to classify gene expression datasets. Unlike the most classification algorithms, which select dimensions (genes) heuristically to form rules groups to identify classes such as cancerous and normal tissues, our algorithm guarantees finding out best-k dimensions (genes) to form rule groups for the classification of expression datasets. Our experiments show that the rule groups obtained by our algorithm have higher accuracy than that of other classification approaches.

Where is the rate in the rule?

A well-developed understanding of rate is foundational to conceptual understanding of introductory calculus. Many students achieve procedural competence with the application of rules for differentiation without developing an awareness of the connection between derivative and rate. In addition, rate-related reasoning is needed to make informed decisions in many everyday applications of rate. This paper reports on additional data collected during interviews for a project investigating the different ways rate may be experienced by pre-calculus students. Many researchers (for example Kaput, 1999) have suggested that the conceptual understanding of function may be enhanced through the presentation and exploration of multiple representations of a variety of functions. In this paper, one section of each interview is considered in detail to evaluate the participants’ understanding in a specific rate context. Participants were asked to discuss a dynamic geometry simulation of a blind on two different windows one rectangular and the other not. Detailed analysis of the video-record of each participant’s interview provides insights into their perceptions of rate in several different representations. In the sections below, the conceptual framework is described; details of the interviews and the computer-based simulation are provided; and the analysis of the data is discussed.

Influenza A virus-specific CD8.sup.+ T-cell responses : from induction to function

Seasonal influenza virus infection is a leading cause of illness and mortality in young children and the elderly each year. Current influenza vaccines generate protective antibody responses; however, these must be given annually to provide protection against serologically distinct viruses. By contrast, CD8.sup.+ T cells are capable of recognizing conserved antigenic determinants within the influenza virion and, as such, may provide protection against a number of variant strains of the virus. CD8.sup.+ T cells play a critical key role in controlling and resolving influenza virus infections via the production of cytokines and cytolytic mediators. This article focuses on the induction of the influenza-specific CD8.sup.+ T-cell response and how these cells acquire and maintain effector function after induction. Moreover, we discuss how cytotoxic T-lymphocyte function correlates with protection following vaccination.

Policing, rule of law, state capacity and sustainable peace in Timor-Leste

This paper sets out to demonstrate the link between development, state capacity and peace, employing Timor-Leste as the case study. It employs the association between state capacity and development to illustrate where if state capacity is lacking or functions improperly there is likely to be a low level of state legitimacy. This in turn manifests as lack of respect for or failure of rule of law, developing as generalised lawlessness and anti-state activity and eventually manifesting as intra-state or civil conflict. In particular, policing is seen as a critical component in state legitimacy, being the 'front line' of the judicial system from which legitimacy ultimately derives. This issue is particularly critical in states emerging from traditional legal and judicial structures, but which have not yet articulated into 'rational-legal' structures. Ipso facto, key state institutions, such as the judicial system and police are required to function well, while these are alone not enough to guarantee peace, they are significant contributors to and guarantors of peace.

Potential applications of discrete-event simulation and fuzzy rule-based systems to structural reliability and availability

This chapter discusses and illustrates some potential applications of discrete-event simulation (DES) techniques in structural reliability and availability analysis, emphasizing the convenience of using probabilistic approaches in modern building and civil engineering practices. After reviewing existing literature on the topic, some advantages of probabilistic techniques over analytical ones are highlighted. Then, we introduce a general framework for performing structural reliability and availability analysis through DES. Our methodology proposes the use of statistical distributions and techniques – such as survival analysis – to model component-level reliability. Then, using failure- and repair-time distributions and information about the structural logical topology (which allows determination of the structural state from their components’ state), structural reliability, and availability information can be inferred. Two numerical examples illustrate some potential applications of the proposed methodology to achieving more reliable and structural designs. Finally, an alternative approach to model uncertainty at component level is also introduced as ongoing work. This new approach is based on the use of fuzzy rule-based systems and it allows the introduction of experts’ opinions and evaluations in our methodology.

A partnership in induction and mentoring : noticing how we improve our practice

This article focuses on the induction and mentoring of early career teachers. The context is a suburban primary school in Victoria, Australia, as the school develops mentoring networks for graduate and beginning teachers. Instigated from a school–university partnership, the research draws from the traditions of practitioner research. In the research design and likewise in successful mentoring the importance of a genuine commitment to the discipline of reflective practice or what we have come to describe as “ noticing ” (Mason, 2002; Moss et al., 2004) is illustrated. The approach offers a new method for small scale–close up research in teacher education.

Geographical variation in bill size across bird species provides evidence for Allen's rule

Allen’s rule proposes that the appendages of endotherms are smaller, relative to body size, in colder climates, in order to reduce heat loss. Empirical support for Allen’s rule is mainly derived from occasional reports of geographical clines in extremity size of individual species. Interspecific evidence is restricted to two studies of leg proportions in seabirds and shorebirds. We used phylogenetic comparative analyses of 214 bird species to examine whether bird bills, significant sites of heat exchange, conform to Allen’s rule. The species comprised eight diverse taxonomic groups—toucans, African barbets, Australian parrots, estrildid finches, Canadian galliforms, penguins, gulls, and terns. Across all species, there were strongly significant relationships between bill length and both latitude and environmental temperature, with species in colder climates having significantly shorter bills. Patterns supporting Allen’s rule in relation to latitudinal or altitudinal distribution held within all groups except the finches. Evidence for a direct association with temperature was found within four groups (parrots, galliforms, penguins, and gulls). Support for Allen’s rule in leg elements was weaker, suggesting that bird bills may be more susceptible to thermoregulatory constraints generally. Our results provide the strongest comparative support yet published for Allen’s rule and demonstrate that thermoregulation has been an important factor in shaping the evolution of bird bills.