We offer a formal account of the English past tenses. We see the perfect as having reference time at speech time and the preterite as having reference time at event time. We formalize four constraints on reference time, which we bundle together under the term ‘perspective’. Once these constraints are satisfied at the different reference times of the perfect and preterite, the contrasting functions of these tenses are explained. Thus we can account formally for the ‘definiteness effect’ and the ‘lifetime (...) effect’ of the perfect, for the fact that the perfect seems to ‘explain’ something about the present, and that the perfect cannot presuppose a past time point. We explain why perfect and preterite can sometimes be interchangeable, and we offer a solution to the ’present perfect puzzle’. We explain the unacceptability of notorious examples of the perfect such as * Gutenberg has discovered the art of printing . We give greater definition to the familiar notions of ‘current relevance’ and ‘extended now’. (shrink)

We propose a model mechanism for the initiation and spatial positioning of teeth primordia in the alligator, Alligator mississippiensis. Detailed embryological studies by Westergaard and Ferguson have shown that jaw growth plays a crucial role in the developmental patterning of the tooth initiation process. Based on biological data we develop a dynamic patterning mechanism, which crucially includes domain growth. The mechanism can reproduce the spatial pattern development of the first seven teeth primordia in each half jaw of A. mississippiensis. The (...) results for the precise spatio-temporal sequence compare well with experiment. Simulation of the model also predicts that certain transplantations can alter the spatial sequence of teeth primordia initiation. (shrink)

At some time around August 324b.c., Antipater, the regent of Macedonia received orders from Alexander the Great that he was to be replaced with another eminent officer in the Macedonian court, Craterus. In addition to his removal from office, Antipater was ordered by Alexander to leave Macedonia for the East, bringing with him fresh levies to replenish those that comprised Craterus' own contingent of veterans from Opis. Though Craterus left Alexander's court shortly thereafter, neither man can be said to have (...) made the journey speedily or directly. A range of reasons has been given to explain Craterus' slow advancement, including the construction of infrastructure to allow the transportation of military resources from east to west, the poor state of his health, and the need to recruit more men. By the time of Alexander's death in June of 323, Craterus and his forces had only reached the province of Cilicia in southeastern Anatolia. Antipater's immediate reaction to his new role is not recorded, but what is known is that he remained steadfast in Macedonia, seemingly in defiance of Alexander's orders. It is the purpose of this paper to evaluate Antipater's refusal to depart from Macedonia, to explore whether tensions between Antipater and his replacement could account for Craterus' sluggish advance and to highlight the impact that Greek domestic politics had on Antipater's position in Macedonia. (shrink)

OBJECTIVES: This study was designed to identify and compare the attitudes of patients and health care professionals towards advance directives. Advance directives promote recognition of the patient's autonomy, letting the individual exercise a certain measure of control over life-sustaining care and treatment in the eventuality of becoming incompetent. DESIGN: Attitudes to advance directives were evaluated using a 44-item self-reported questionnaire. It yields an overall score as well as five factor scores: autonomy, beneficence, justice, external norms, and the affective dimension. SETTING: (...) Health care institutions in the province of Québec, Canada. Survey sample: The sampling consisted of 921 subjects: 123 patients, 167 physicians, 340 nurses and 291 administrators of health care institutions. RESULTS: Although the general attitude of each population was favourable to the expression of autonomy, multivariate analysis of variance (MANOVA) indicated that physicians attached less importance to this subscale than did other populations (p < .001). Above all, they favoured legal external norms and beneficence. Physicians and administrators also attached less importance to the affective dimension than did patients and nurses. Specifically, physicians' attitudes towards advance directives were shown to be less positive than patients' attitudes. CONCLUSION: More attention should be given to the importance of adequately informing patients about advance directives because they may not represent an adequate means for patients to assert their autonomy. (shrink)

This article aims to further test the cognitive claims of the so-called subjectivity account of causal events and their linguistic markers, causal connectives. We took Mandarin Chinese, a language that is typologically completely different from the usual western languages, as a case to provide evidence for this subjectivity account. Complementary to the commonly used corpora analyses, we employed crowdsourcing to tap native speakers’ intuitions about causal coherence, focusing on four result connectives kějiàn ‘therefore’, suǒyǐ ‘so’, yīncǐ ‘so/for this reason’ and (...) yúshì ‘thereupon/as a result’. The analysis shows systematic differences regarding the use of connectives in relations that differ in terms of subjectivity, demonstrating that native speakers make use of subjectivity to encode and decode different types of causal relations in discourse. Moreover, our study evidences that a comprehensive model of subjectivity should include the epistemic dimension of certainty about the subjectivity scale that might be indicated by other linguistic elements. In-depth analyses of the test items revealed that the presence/absence of modality words in the result segments are related to different preferential patterns for the connectives. There is a trade-off between the epistemic dimension of certainty and the expression of subjectivity in the four connectives involved. (shrink)

The human blood coagulation system comprises a series of linked glycoproteins that upon activation induce the generation of downstream enzymes ultimately forming fibrin. This process is primarily important to arrest bleeding (hemostasis). Hemostasis is a typical example of a molecular machine, where the assembly of substrates, enzymes, protein cofactors and calcium ions on a phospholipid surface markedly accelerates the rate of coagulation. Excess, pathological, coagulation activity occurs in “thrombosis”, the formation of an intravascular clot, which in the most dramatic form (...) precipitates in the microvasculature as disseminated intravascular coagulation. Thrombosis occurs according to a biochemical machine model in the case of atherothrombosis on a ruptured atherosclerotic plaque, but may develop at a slower rate in venous thrombosis, illustrating that the coagulation machinery can act at different velocities. The separate coagulation enzymes are also important in other biological processes, including inflammation for which the rapid conversion of one coagulation factor by the other is not a prerequisite. The latter role of coagulation enzymes may be related to the old and probably maintained function of the coagulation machine in innate immunity. BioEssays 25:1220–1228, 2003. © 2003 Wiley Perioicals, Inc. (shrink)

We report specific heat and μSR measurements on Th and/or B substituted UBe13. The specific heat data show that either Th or B substitution reduces the Kondo temperature TK and increases the entropy at the superconducting transition by almost 20%, indicating an enhanced density of states. However, whereas μSR shows clear evidence for magnetic correlations for Th substitutions, no magnetism is observed for B substitutions. The enhanced specific heat jump in the B-substituted material is associated with a change in the (...) superconducting properties as TK is reduced. (shrink)

We apply an online optimization process based on machine learning to the production of Bose-Einstein condensates. BEC is typically created with an exponential evaporation ramp that is optimal for ergodic dynamics with two-body s-wave interactions and no other loss rates, but likely sub-optimal for real experiments. Through repeated machine-controlled scientific experimentation and observations our ’learner’ discovers an optimal evaporation ramp for BEC production. In contrast to previous work, our learner uses a Gaussian process to develop a statistical model of the (...) relationship between the parameters it controls and the quality of the BEC produced. We demonstrate that the Gaussian process machine learner is able to discover a ramp that produces high quality BECs in 10 times fewer iterations than a previously used online optimization technique. Furthermore, we show the internal model developed can be used to determine which parameters are essential in BEC creation and which are unimportant, providing insight into the optimization process of the system. (shrink)

This article presents an overview ofregulations, guidelines and societal debates ineight member states of the EC about a)embryonic and fetal tissue transplantation(EFTT), and b) the use of human embryonic stemcells (hES cells) for research into celltherapy, including `therapeutic' cloning. Thereappears to be a broad acceptance of EFTT inthese countries. In most countries guidance hasbeen developed. There is a `strong' consensusabout some of the central conditions for `goodclinical practice' regarding EFTT.International differences concern, amongstothers, some of the informed consent issuesinvolved, and the (...) questions whether anintermediary organisation is necessary, whetherthe methods of abortion may be influenced bythe possible use of EFT, and whether EFTTshould only be used for the experimentaltreatment of rare disorders. The potential useof hES cells for research into cell therapy hasgiven a new impetus to the debate about (human)embryo research. The therapeutic prospects withregard to the retrieval and research use of hEScells appear to function as a catalyst for theintroduction of less restrictive regulationsconcerning research with spare embryos, atleast in some European countries. It remains tobe seen whether the prospect of treatingpatients suffering from serious disorders withtransplants produced by therapeutic cloningwill decrease the societal and moral resistanceto allowing the generation of embryos for`instrumental' use. (shrink)

Language’s intentional nature has been highlighted as a crucial feature distinguishing it from other communication systems. Specifically, language is often thought to depend on highly structured intentional action and mutual mindreading by a communicator and recipient. Whilst similar abilities in animals can shed light on the evolution of intentionality, they remain challenging to detect unambiguously. We revisit animal intentional communication and suggest that progress in identifying analogous capacities has been complicated by (i) the assumption that intentional (that is, voluntary) production (...) of communicative acts requires mental-state attribution, and (ii) variation in approaches investigating communication across sensory modalities. To move forward, we argue that a framework fusing research across modalities and species is required. We structure intentional communication into a series of requirements, each of which can be operationalised, investigated empirically, and must be met for purposive, intentionally communicative acts to be demonstrated. Our unified approach helps elucidate the distribution of animal intentional communication and subsequently serves to clarify what is meant by attributions of intentional communication in animals and humans. (shrink)