In Chapters 6 and 7 of Language, Truth and Poetry I attempted to solve the ancient problem of fictional reference by claiming that a fictional construct ‘points’ or refers to certain features of reality in rather the same way as an abstraction like ‘gravitation’ or ‘cruelty’ does. I now believe that this theory of mine is unsatisfactory; and I should like to propose a new solution to the problem.

Here we elucidate a paradox: how a single chemoattractant‐receptor system in two individuals is used for communication despite the seeming inevitability of self‐excitation. In the filamentous fungus Neurospora crassa, genetically identical cells that produce the same chemoattractant fuse via the homing of individual cell protrusions toward each other. This is achieved via a recently described “ping‐pong” pulsatile communication. Using a generic activator‐inhibitor model of excitable behavior, we demonstrate that the pulse exchange can be fully understood in terms of two excitable (...) systems locked into a stable oscillatory pattern of mutual excitation. The most puzzling properties of this communication are the sudden onset of oscillations with final amplitude, and the absence of seemingly inevitable self‐excitation. We show that these properties result directly from both the excitability threshold and refractory period characteristic of excitable systems. Our model suggests possible molecular mechanisms for the ping‐pong communication. (shrink)

Photography has become a pervasive component of contemporary communication. Recent technological advances in creating and manipulating images have provided renewed impetus to decades-long debates on use of photographs in science. With increase in the potential for inappropriate image manipulation, fears about misrepresentation have heightened concern among journal editors and scholars about the 'accuracy' of published images. We discuss how science has responded to growing concerns surrounding falsification and inaccuracy of photography. We document progress in implementing a variety of complementary approaches (...) to addressing the problem. These include digital forensics, photo member checking and the implementation of codes of ethics to enhance the veracity of published photographs in science research. We conclude by acknowledging the irreducible conflict likely to remain between use of the photograph as a creative work of art and employment of this medium as a source of information in the progress of science. (shrink)

There is increasing attention given to academic integrity across university education and dental schools are not immune to this problem (Andrews et al. J Dent Educ 71; 1027–1039, 2007; Ford & Hughes Eur J Dent Educ 16(1):e180–e186, 2012). While there has been an increasing concern about academic dishonesty in written exams and assignments, there appears to be a false sense of security in the integrity of practical assessments, involving dental procedures on simulated patients.This paper will present a situational analysis of (...) two unusual cases of academic dishonesty in preclinical dental practical assessments. The first case involved a student bringing a previously prepared plastic tooth into the examination room and substituting it for the assessment tooth. The second case involved a student removing key teeth during the exam to enable them to have better access and advantage over others to complete the assessment task. These two cases resulted in a complete review of practical assessment procedures and the application of new processes to maintain academic integrity. (shrink)

Mammalian AMP‐activated protein kinase is the central component of a protein kinase cascade which inactivates three key enzymes involved in the synthesis or release of free fatty acids and cholesterol inside the cell. The kinase cascade is activated by elevation of AMP, and perhaps also by fatty acid and cholesterol metabolites. The system may fulfil a protective function, preventing damage caused by depletion of ATP or excessive intracellular release of free lipids, a type of stress response. Recent evidence suggests that (...) it may have been in existence for at least a billion years, since a very similar protein kinase cascade is present in higher plants. This system therefore represents an early eukaryotic protein kinase cascade, which is unique in that it is regulated by intracellular metabolites rather than extracellular signals or cell cycle events. (shrink)

This special volume of Studies in Christian Ethics constitutes the most significant continuation to date of Christian social ethics in the tradition of Ronald Preston. It brings together leading scholars and new voices in the field from around the world, covering a broad range of contemporary issues, including globalisation, poverty, feminism, civil society, economics and religious pluralism.

The aim of this article is to examine some of the consequences of the recent advances in neurobiology in terms of the ability of drugs to manipulate the mind. Most laymen are totally ignorant of the general mechanism underlying the brain-mind relationship and therefore of the action of mind-altering drugs. Professor Grahame-Smith considers that one of the intrinsic evils of man's neurobiological make up is that a prime motive of the brain seems to be to bring comfort, security and pleasure (...) for itself. Therefore it is not surprising that drugs - notably the barbiturates and more recently the benzodiazepines (tranquilizers) - have been prescribed to give to the brain that peace of mind that it seeks. However, it can be argued that such drugs cannot replace anxiety with peace of mind or unhappiness or depression with happiness. The action of such drugs upon the molecules of the brain is negative - a placebo effect. (shrink)

This paper provides a survey of philosophical discussion of the "the Turing Test". In particular, it provides a very careful and thorough discussion of the famous 1950 paper that was published in Mind.

The foundations of systematics lie in ontology, not in subjective epistemology. Systems and their elements should be distinguished from classes; only the latter are constructed from similarities. The term classification should be restricted to ordering into classes; ordering according to systematic relations may be called systematization.The theory of organization levels portrays the real world as a hierarchy of open systems, from energy quanta to ecosystems; followingHartmann these systems as extended in time are considered the primary units of reality. Organization levels (...) should be distinguished from levels of differentiation within each organization level.Certain biological systems, such as species, continue to be misinterpreted as classes, particularly by logicians unfamiliar with modern biological theory. Replacement of Aristotelian definitions of species by “polytypic” definitions achieves nothing, because species are individual systems which can be defined from an ontological viewpoint only as wholes. The dispute whether classes are real per se or only in individuals is of no scientific importance; irrespective of which view is taken, any ordering of physical objects into classes constitutes an hypothesis about the structure of the real world.The distinction between essential and contingent characters is relevant only to classification. There are no universal rules for evaluating characters for purposes of systematization. Character statements do not form separate linear sequences. The search for “unit characters” in an absolute sense is futile. All real characters are reducible to relations and are in principle measurable, although there are limitations on the extent to which this can be presently achieved.The concept of the sexual species is fundamental to theories of biosystematics. Sexual species may be defined as lineages consisting at any given time of series of populations between which genetic exchange can occur and delimited in time by two successive processes of speciation. Linnaean nomenclature needs modification; in its traditional form it is appropriate only to non-truncated hierarchies, whereas real phylogenies form truncated hierarchies. In consequence of the distinction between systematization and classification it is concluded that, while taxa may be classified into age classes or evolutionary grades, their limits as taxa can be no different in either case. Classification into evolutionary grades remains an imprecise endeavour, since no general measure of evolutionary differentiation has been devised.The spatial and temporal extent of ecosystems, the postulated basic units of ecosystematics, remains unclarified. Nevertheless there are grounds for expecting progress in this field as the energetic relations between organisms become better understood. Biotic communities are not “abstract” classes, but systematic units. Physiognomic classification should not be confused with systematization of plant communities; both approaches contribute to an understanding of vegetational structure. (shrink)

From Galileo to the Bhopal tort litigation, Scopes to OncoMouse®, Lysenko to the lie detector, the agonistic and alethic forum of the courtroom has offered unique opportunities to witness science and scientists being made and unmade. Evolving legal systems have consistently been forced to draw on (or defensibly away from) scientific knowledge, scientific methods, and scientific experts in the pursuit of truth and justice. At the same time, courts—in many ways the original site for the production of social facts—have to (...) a significant extent shaped both the theories and the practices of knowledge production central to the emergence of modern science. This Focus section draws together a set of scholars at work on these borrowings and aims to stimulate more research in an important and fast‐expanding area of scholarship. (shrink)

The real history of the covey of attention-artists who call themselves "The Birds." A great deal of uncertainty--and even some genuine confusion--surrounds the origin, evolution, and activities of the so-called Avis Tertia or "Order of the Third Bird." Sensational accounts of this "attentional cult" emphasize histrionic rituals, tragic trance-addictions, and the covert dissemination of obscurantist ontologies of the art object. Hieratic, ecstatic, and endlessly evasive, the Order attracts sensual misfits and cabalistic aesthetes--both to its ranks, and to its scholarship. In (...) recent years, however, the revisionist work of the research collective ESTAR(SER) has done much to clear the air, bringing archival precision to the history of this covey of attention-artists who call themselves "The Birds." Gathering the best articles of the last twenty years of The Proceedings of ESTAR(SER), this volume represents a landmark in the history of aesthetic practices, and will be a point of departure for future work wading the muddy marshes at the limits of historicism."--Publisher description. (shrink)

Emerging research shows a strong connection between brain areas governing cognition and motor behavior. Yet, research investigating the negative aftereffects of cognitive control exertion on task performance has not considered the potential role of areas governing motor behavior. The present study investigated the effects of high cognitive control exertion on task self-efficacy and exercise performance in children. A secondary purpose was to investigate whether motor coordination influences the change in exercise performance differently following low versus high cognitive control exertion. Participants (...) (N = 70) performed two isometric handgrip endurance trials separated by a Stroop task, which was either congruent (low cognitive control) or incongruent (high cognitive control). Motor coordination was assessed prior to the first endurance trial. Task self-efficacy for performing the second endurance trial was assessed following the Stroop task. Participants in the high cognitive control condition reported lower task self-efficacy and showed a reduction in endurance exercise performance. Task self-efficacy mediated the cognitive control – performance relationship. Participants scoring lower on motor coordination showed the greatest declines in exercise performance following high cognitive control, whereas motor coordination did not affect performance following low cognitive control. The results of this study provide evidence that task self-efficacy and exercise performance are also negatively affected in children following high cognitive control, and interestingly, these effects are exacerbated among those scoring lower in motor coordination. We recommend future research investigate motor coordination as a potential mechanism for the reductions in both cognitive and physical task performance following the prolonged exertion of high cognitive control. (shrink)

School-aged children with Developmental Coordination Disorder (DCD) are at greater risk for physical inactivity, lower global self-worth, and internalizing problems, such as depression and anxiety. Based on the Environmental Stress Hypothesis (ESH), recent research has shown that physical inactivity and lower global self-worth sequentially mediate the relationship between DCD and internalizing problems, suggesting that DCD leads to lower levels of physical activity, which in turn, leads to lower levels of global self-worth, and ultimately, a greater amount of internalizing problems. However, (...) physical activity and global self-worth may also buffer (i.e., moderate) the adverse effect of DCD on internalizing problems. To date, this has yet to be tested. Participants were 1206 children aged 12-14 years (611 boys, 79 with probable DCD (pDCD)). All children received assessments of motor coordination, physical activity, global self-worth, and internalizing problems. Children with pDCD were less physically active, had lower self-worth, and experienced more internalizing problems compared to typically developing (TD) children (p’s <.05). Furthermore, the moderated moderating effect (three-way interaction) of physical activity and global self-worth was also evident (p <.05), indicating that internalizing problems in both TD and pDCD groups decreased with concurrent increases in physical activity and global self-worth. Importantly, when compared to TD children, increases in physical activity and global self-worth were associated with a greater reduction in internalizing problems among children with pDCD. The findings support several pathways in the ESH and highlight that, in addition to improving motor skills, interventions should also target both physical activity and global self-worth to mitigate potential mental health issues for children with motor difficulties. (shrink)

The present study investigated the influence of emotional stimuli in the flanker task. In six experiments, separate influences of anticipating and reacting to valence-laden stimuli (affective pictures or facial expressions) on the flanker effect and its sequential modulation (also known as conflict adaptation) were examined. The results showed that there was little evidence that emotional stimuli influenced cognitive control when positive and negative stimuli appeared randomly during the flanker task. When positive and negative stimuli were separated between different participant groups (...) in order to exclude a possible contamination from the effect of one valence to that of another, the sequential modulation was reduced when valence-laden stimuli were anticipated or had been presented on a preceding trial, regardless of the valence of the stimuli. A similar pattern was also obtained with facial expressions but only for response accuracy and only after valence-laden stimuli were presented on a preceding trial. The influences of anticipating and reacting to emotional stimuli were only partially replicated in the final two experiments where the arousal and valence of affective pictures were manipulated orthogonally. The lack of consistent influences of emotional stimuli on the flanker effect challenges the existing theories that implicate affective contributions to cognitive control. (shrink)

We address two main issues: the distinction between time-constrained and spatially constrained tasks, and the separable A and W effects on movement time (MT) in spatially-constrained tasks. We consider MT and 3-D kinematic data from human adults pointing to targets in human-computer interaction. These are better fit by Welford's (1968) two-part model, than Fitts' (1954; Fitts & Peterson 1964) ID model. We identify theoretical and practical implications.

This book presents some of the most recent trends and developments in Presocratic scholarship. A wide range of topics are covered - from the metaphysical to the moral to the methodological - as well as a broad a range of authors: from recognized figures such as Heraclitus and Parmenides to Sophistic thinkers whose place has traditionally been marginalized, such as Gorgias and the author of the Dissoi Logoi. Several of the pieces are concerned with the later reception and influence of (...) the Presocratics on ancient philosophy, an area of study important both for the light it sheds on our evidence for Presocratic thought and for understanding the philosophical power of their ideas. Drawing together contributions from distinguished authorities and internationally acclaimed scholars of ancient philosophy, this book offers new challenges to traditional interpretations in some areas of Presocratic philosophy and finds new support for traditional interpretations in other areas. (shrink)

The feasibility of reversing human aging within a matter of decades has traditionally been dismissed by all professional biogerontologists, on the grounds that not only is aging still poorly understood, but also many of those aspects that we do understand are not reversible by any current or foreseeable therapeutic regimen. This broad consensus has recently been challenged by the publication, by five respected experimentalists in diverse subfields of biogerontology together with three of the present authors, of an article (Ann NY (...) Acad Sci 959, 452–462) whose conclusion was that all the key components of mammalian aging are indeed amenable to substantial reversal (not merely retardation) in mice, with technology that has a reasonable prospect of being developed within about a decade. Translation of that panel of interventions to humans who are already alive, within a few decades thereafter, was deemed potentially feasible (though it was not claimed to be likely). If the prospect of controlling human aging within the foreseeable future cannot be categorically rejected, then it becomes a matter of personal significance to most people presently alive. Consequently, we suggest that serious public debate on this subject is now warranted, and we survey here several of the biological, social and political issues relating to it. BioEssays 24:667–676, 2002. © 2002 Wiley Periodicals, Inc. (shrink)

In a recent essay, George Annas, the legal columnist for The New England Journal of Medicine, observed that the resuscitation of extremely premature infants, even over parental objection, is not problematic because “once the child's medical status has been determined, the parents have the legal authority to make all subsequent decisions.” Annas himself is quick to concede that treatment in a high-technology neonatal intensive care unit frequently takes on a life of its own. He also acknowledges that although bioethicists and (...) courts agree that there is no ethical or legal difference between withholding or withdrawing a respirator from a patient, parents and physicians find the withdrawal much more emotionally troubling. (shrink)

The thymus is a unique primary lymphoid organ that supports the production of self‐tolerant T‐cells essential for adaptive immunity. Intrathymic microenvironments are microanatomically compartmentalised, forming defined cortical, and medullary regions each differentially supporting critical aspects of thymus‐dependent T‐cell maturation. Importantly, the specific functional properties of thymic cortical and medullary compartments are defined by highly specialised thymic epithelial cells (TEC). For example, in the medulla heterogenous medullary TEC (mTEC) contribute to the enforcement of central tolerance by supporting deletion of autoreactive T‐cell (...) clones, thereby counterbalancing the potential for random T‐cell receptor generation to contribute to autoimmune disease. Recent advances have further shed light on the pathways and mechanisms that control heterogeneous mTEC development and how differential mTEC functionality contributes to control self‐tolerant T‐cell development. Here we discuss recent findings in relation to mTEC development and highlight examples of how mTEC diversity contribute to thymus medulla function. (shrink)