Chemosensory systems are complex regulatory pathways capable of perceiving external signals and translating them into different cellular behaviors such as motility and development. In the δ-proteobacterium Myxococcus xanthus, chemosensing allows groups of cells to orient themselves and aggregate into specialized multicellular biofilms termed fruiting bodies. M. xanthus contains eight predicted CSS and 21 chemoreceptors. In this work, we systematically deleted genes encoding components of each CSS and chemoreceptors and determined their effects on M. xanthus social behaviors. Then, to understand how (...) the 21 chemoreceptors are distributed among the eight CSS, we examined their phylogenetic distribution, genomic organization and subcellular localization. We found that, in vivo, receptors belonging to the same phylogenetic group colocalize and interact with CSS components of the respective phylogenetic group. Finally, we identified a large chemosensory module formed by three interconnected CSS and multiple chemoreceptors and showed that complex behaviors such as cell group motility and biofilm formation require regulatory apparatus composed of multiple interconnected Che-like systems. © 2014 Moine et al. (shrink)

Larry Hardin has been the most steadfast and influential critic of physicalist theories of color over the last 20 years. In their modern form these theories originated with the work of Smart and Armstrong in the 1960s and 1970s1 and Hardin appropriately concentrated on their views in his initial critique of physicalism.2 In his most recent contribution to this project3 he attacks Michael Tye’s recent attempts to defend and extend color physicalism.4 Like Byrne and Hilbert5, Tye identifies color with the (...) reflecting properties of objects (“reflectance physicalism”). Specifically, the determinate and determinable colors are identified with types of reflectances. (Setting some complications aside, the reflectance of an object is the proportion of light that it reflects at each wavelength in the visible spectrum.) These reflectance types are, in the terminology of Hilbert, anthropocentric—in the terminology of Lewis6, they are not very “natural”. (shrink)

Written by some of the world's leading academics and professionals in the field, this collection of essays brings together two complementary views on child development - the role of society and the role of cognitive growth.

Previous research suggests that early performance of amnesic individuals in a probabilistic category learning task is relatively unimpaired. When combined with impaired declarative knowledge, this is taken as evidence for the existence of separate implicit and explicit memory systems. The present study contains a more fine-grained analysis of learning than earlier studies. Using a dynamic lens model approach with plausible learning models, we found that the learning process is indeed indistinguishable between an amnesic and control group. However, in contrast to (...) earlier findings, we found that explicit knowledge of the task structure is also good in both the amnesic and the control group. This is inconsistent with a crucial prediction from the multiple-systems account. The results can be explained from a single system account and previously found differences in later categorization performance can be accounted for by a difference in learning rate. (shrink)

Colour has often been supposed to be a subjective property, a property to be analysed orretly in terms of the phenomenological aspects of human expereince. In contrast with subjectivism, an objectivist analysis of color takes color to be a property objects possess in themselves, independently of the character of human perceptual expereince. David Hilbert defends a form of objectivism that identifies color with a physical property of surfaces - their spectral reflectance. This analysis of color is shown to provide (...) a more adequate account of the features of human color vision than its subjectivist rivals. The author's account of colro also recognises that the human perceptual system provides a limited and idiosyncratic picture of the world. These limitations are shown to be consistent with a realist account of colour and to provide the necessary tools for giving an analysis of common sense knowledge of color phenomena. (shrink)

INTRODUCTION Linguists who work within the tradition of transformational generative grammar tend to regard semantics as an intractable, perhaps ultimately ...

Throughout his life J. J. Thomson was committed to a mechanical interpretation of nature. This work proceeded in several stages. Early in his career he attempted a Lagrangian formulation of mechanics. But due to certain epistemological difficulties with this approach, he began exploring various analogies and models, particularly those involving vortex motion. After his discovery of the electron in 1897, he commenced a synthesis of the electron with his previous physical conceptions. The result was a hypothesis of the ether as (...) being composed of particles even smaller than electrons. (shrink)

Although the importance of literacy is widely acknowledged in society and remains at the top of the political agenda, writing has been slow to establish a place in the cognitive sciences. Olson argues that to understand the cognitive implications of literacy, it is necessary to see reading and writing as providing access to and consciousness of aspects of language, such as phonemes, words and sentences, that are implicit and unconscious in speech. Reading and writing create a system of metarepresentational concepts (...) that bring those features of language into consciousness as a subject of discourse. This consciousness of language is essential not only to acquiring literacy but also to the formation of systematic thought and rationality. The Mind on Paper is a compelling exploration of what literacy does for our speech and hence for our thought, and will be of interest to readers in developmental psychology, cognitive science, linguistics, and education. (shrink)

Multiple cue probability learning studies have typically focused on stationary environments. We present three experiments investigating learning in changing environments. A fine-grained analysis of the learning dynamics shows that participants were responsive to both abrupt and gradual changes in cue-outcome relations. We found no evidence that participants adapted to these types of change in qualitatively different ways. Also, in contrast to earlier claims that these tasks are learned implicitly, participants showed good insight into what they learned. By fitting formal learning (...) models, we investigated whether participants learned global functional relationships or made localized predictions from similar experienced exemplars. Both a local (the Associative Learning Model) and a global learning model (the novel Bayesian Linear Filter) fitted the data of the first two experiments. However, the results of Experiment 3, which was specifically designed to discriminate between local and global learning models, provided more support for global learning models. Finally, we present a novel model to account for the cue competition effects found in previous research and displayed by some of our participants. (shrink)

Time pressure has been shown to have a negative impact on ethical decision-making. This paper uses an experimental approach to examine the impact of an antecedent of time pressure, whether it is anticipated or not, on participants’ perceptions of unethical behaviour. Utilising 60 business school students at an Australian university, we examine the differential impact of anticipated and unanticipated time deadline pressure on participants’ perceptions of the likelihood of unethical behaviour occurring. We find the perception of the likelihood of unethical (...) behaviour occurring to be significantly reduced when time pressure is anticipated rather than unanticipated. The implications of this finding for both professional service organisations and tertiary institutions are considered. (shrink)

This article reprints the text of a review of adam smith's "theory of moral sentiments", And presents arguments for ascribing it to david hume. Hume's subsequent criticism of what he called "the hinge" of adam smith's moral system ("viz." that "all kinds of sympathy are necessarily agreeable") is also examined, And it is argued that smith failed to appreciate the nature and extent of this criticism. It is concluded that "the hinge" of smith's novel theory is a false assumption; (...) yet without it smith cannot present a viable alternative to hume's explanation of the origin of our moral sentiments. (shrink)

Dimorphism in the yeast Candida albicans provides an unusually simple model system for investigating the mechanisms which regulate cellular differentiation, or cell divergence. Under the regime of pH‐regulated dimorphism, it has been demonstrated that the programs of protein synthesis accompanying bud and hypha formation are strikingly similar. Instead of dramatic differences in the repertoire of gene products possessed by bud‐ and hypha‐forming cells, subtle temporal, spatial and quantitative differences in the same architectural events appear to be basic to the genesis (...) of alternative phenotypes. This emerging story of phenotypic regulation does not exclude differential gene expression, but rather de‐emphasizes its role and underscores other mechanisms which are not generally considered. (shrink)

An in-depth study of Kierkegaard's thinking on Christology, emphasising the radical nature of his approach to the incarnation, with an emphasis on the call of the Christian believer to a life of 'kenotic' (self-emptying) discipleship in imitation of Christ.

The final lines of Deleuze and Guattari’s What is Philosophy? call for a non-philosophy to balance and act as a counterweight to the task of philosophy that had been described by them in terms of concept creation. In a footnote, Deleuze and Guattari mention François Laruelle’s project of non-philosophy, but dispute its efficacy in terms of the designated relationship between non-philosophy and science, as had been realised by Laruelle at the time. However, the mature non-philosophy of Laruelle could indicate a (...) resolution to the problematic relationship between science and educational philosophy that we have inherited due to the poststructural theories of Foucault, Derrida and Deleuze. Non-philosophy suggests a framework for thought that includes science in a non-positivist style and provides the means to view education as a performative practice. This article explores the non-philosophy of Laruelle in education as a means to view education under the conditions of strict immanence and in line with an anti-phenomenological metaphysics of non-representation. Laruelle is perhaps one of the most important critics of Deleuze in France, and as such, his insights into the Deleuzian oeuvre reveal a way forward for education as a practice that analyses science, philosophy and politics through non-philosophy. (shrink)

There are serious reasons for accepting each of these propositions individually but there are apparently insurmountable difficulties with accepting all three of them simultaneously if we assume that color is a single property. 1) and 2) together seem to imply that there is some property which all organisms with color vision can see and 3) seems to imply that there can be no such property. If these implications really are valid then one or more of these propositions will have to (...) be rejected in spite of whatever reasons can be given for their apparent acceptability. Before going on to discuss possible resolutions of this apparent contradiction it is worth pointing out there our three propositions are not all of a kind. Proposition 1) is a metaphysical thesis about the ontological status of color and proposition 3) is an empirical thesis about what properties organisms with color vision are capable of detecting. If you accept 1) then 2) will appear to verge on the trivial, but if 1) is denied then the status of 2) will appear more problematic. In what follows I will have more to say about why we either should or should not accept all three of these propositions. (shrink)

Our shared moral framework is negotiated as part of the social contract. Some elements of that framework are established (tell the truth under oath), but other elements lack an overlapping consensus (just when can an individual lie to protect his or her privacy?). The tidy bits of our accepted moral framework have been codified, becoming the subject of legal rather than ethical consideration. Those elements remaining in the realm of ethics seem fragmented and inconsistent. Yet, our engineering students will need (...) to navigate the broken ground of this complex moral landscape. A minimalist approach would leave our students with formulated dogma—principles of right and wrong such as the National Society for Professional Engineers (NSPE) Code of Ethics for Engineers—but without any insight into the genesis of these principles. A slightly deeper, micro-ethics approach would teach our students to solve ethical problems by applying heuristics—giving our students a rational process to manipulate ethical dilemmas using the same principles simply referenced a priori by dogma. A macro-ethics approach—helping students to inductively construct a posteriori principles from case studies—goes beyond the simple statement or manipulation of principles, but falls short of linking personal moral principles to the larger, social context. Ultimately, it is this social context that requires both the application of ethical principles, and the negotiation of moral values—from an understanding of meta-ethics. (shrink)

The actions of affect are prominent in the philosophy of Gilles Deleuze and can be broken down for the purposes of education into two roles. The first alludes to the history of philosophy and the ways in which affect has been used by Spinoza (Deleuze, 1992) Nietzsche (Deleuze, 1983) or Bergson (Deleuze, 1991). In this role, Deleuze reinvigorates and challenges definitions of affect that would place them into systems of understanding that could take paths to metaphysics or to becoming paradigms (...) for capture in any further theorisation of affect. For example, scholars might attest to the use of affect as defined by Spinoza in the Ethics. Deleuze (1983, 1991, 1992) attends to the ways in which scholarly understanding of affect has been broached in order to free the idea up for empirical studies and also to show that the power of didactic language may be subsumed and subverted. The second role of affect in the work of Deleuze comes about in his first two co-authored books that he produced with Félix Guattari (Deleuze & Guattari, 1984, 1988). These publications have a distinct purpose from the scholarly work, which this article shall examine in terms of educational activism, group identities and the sociology of education. This level imbues the use of language in pedagogic acts with an intense affective resonance and the multiple traces of becoming that might be present in any teaching and learning context. (shrink)

This article reviews recent work aimed at developing a new framework, based on signal detection theory, for understanding the relationship between explicit (e.g., recognition) and implicit (e.g., priming) memory. Within this framework, different assumptions about sources of memorial evidence can be framed. Application to experimental results provides robust evidence for a single-system model in preference to multiple-systems models. This evidence comes from several sources including studies of the effects of amnesia and ageing on explicit and implicit memory. The framework allows (...) a range of concepts in current memory research, such as familiarity, recollection, fluency, and source memory, to be linked to implicit memory. More generally, this work emphasizes the value of modern computational modelling techniques in the study of learning and memory. (shrink)

The introduction of digital games and simulations into science museums has prompted excitement about a new "post-museum" pedagogy emphasizing egalitarianism, interactivity, and personalized approaches to learning. However, many post-museums of science, this article aims to show, enact rhetorical performances that lead visitors to narrowly targeted answers and hide the authority of the expert in a play of tactile and affective activities, thus operating in opposition to many of the basic ideals of the post-museum. The Brain and Cognition Exhibit at the (...) Hong Kong Science Museum serves as a case study for how a post-museum exhibit, through embracing interactivity and visitor-centered tasks, becomes a site where science is tested on and performed through visitors' bodies such that institutional prescriptions are applied. Visitors are not merely encouraged at this exhibit to learn about the brain through doing but are trained to see functional and dysfunctional brains and to then diagnose themselves and their children by playing games and taking brain-measurement tests. As a result, the interactive engagement of the exhibit creates a new space of public medicalization. Reflections and suggestions are offered at the end of the article. (shrink)

In the 1960s claims were made about the role of literacy in restructuring the mind. While those claims were frequently criticized, this paper revives the claim by showing that reading and writing require a new consciousness of properties of language, properties relevant to a distinctive modes of literate thought.