In this paper, I would like to show that considering technological models as they arise in engineering disciplines can greatly enrich the philosophical perspective on models. In fluid mechanics, (at least) three types of models are distinguished: mathematical, computer and physical models. Very often, the choice of a particular mathematical, computer or physical model highly affects the type of solutions and the computational time needed for it. Technological models not only aim at a correct description of the physical (...) phenomena, but also for an efficient and accurate simulation. The problem arises how heterogeneous models of an engineering problem can be brought together and be compared to each other as regards their function and technological efficiency. There are two developments in the history of fluid mechanics that have greatly influenced the use of models in the field: The introduction of the concept of the boundary layer by Ludwig Prandtl in 1904 made it possible to apply ideal analytical solutions, which at the time were almost entirely based on Euler’s equations for inviscid fluids, to interesting real cases and to approximate the theoretical Navier-Stokes equations to practical engineering problems, i.e. to cases at high Reynolds numbers. This made it possible to link the empirical tradition of hydraulics with the theoretical tradition of analytical mechanics and therefore lead to a kind of equilibrium in the use of mathematical and physical models. In the 1970s the introduction of the computer has greatly pushed back the importance of both physical and mathematical (analytic) models alike without making them superfluous. There remain, however, three different ways to conceive of physical models in fluid mechanics, and thus of the experimental ingredient, depending on whether they are devised from an analytical, computational or measurement theoretical point of view. Yet even inside the tradition of computer simulation, different practices have formed according to the programming methods used. The choice of method either depends on considerations of efficiency in terms of costs and time, or on historically contingent factors, like availability of instruments and programming packages or the arbitrary choice of a forerunner. Seen from a technological point of view the factors that make models “autonomous agents” and thus (relatively) independent from theory depend on efficiency constraints. Models are means to solve problems in a certain practical perspective by the most efficient means available. To develop a model is a “fast and frugal way” to get to grips with a certain region of reality, whereas the theoretical approach stresses the importance of universal features. (shrink)

Rationality - as opposed to 'ad-hoc' - and asymptotics - to emphasize the fact that perturbative methods are at the core of the theory - are the two main concepts associated with the Rational Asymptotic Modeling (RAM) approach in fluid dynamics when the goal is to specifically provide useful models accessible to numerical simulation via high-speed computing. This approach has contributed to a fresh understanding of Newtonian fluid flow problems and has opened up new avenues for tackling real (...) fluid flow phenomena, which are known to lead to very difficult mathematical and numerical problems irrespective of turbulence. With the present scientific autobiography the author guides the reader through his somewhat non-traditional career; first discovering fluid mechanics, and then devoting more than fifty years to intense work in the field. Using both personal and general historical contexts, this account will be of benefit to anyone interested in the early and contemporary developments of an important branch of theoretical and computational fluid mechanics. (shrink)

Several paradoxes of infinity have recently featured in this journal involving gases distributed in a denumerable infinite series of compartments. I shall demonstrate in this paper that:a) None of these new paradoxes applies where the gases comply with both Boyle’s law and Avogadro’s law. As several of these new paradoxes expressly require compliance with Boyle’s law, it is unclear, in principle, as to whether there is a plausible model of gas that is able to uphold them all.b) Notwithstanding a), (...) any of the above paradoxes can be reinstated by acknowledging that there are two distinct, non-equivalent concepts of ideal gas. Indeed, the various infinity puzzles actually enable a distinction to be made between the two concepts. (shrink)

This thesis focuses on models of conceptual change in science and philosophy. In particular, I developed a new bootstrapping methodology for studying conceptual change, centered around the formalization of several popular models of conceptual change and the collective assessment of their improved formal versions via nine evaluative dimensions. Among the models of conceptual change treated in the thesis are Carnap’s explication, Lakatos’ concept-stretching, Toulmin’s conceptual populations, Waismann’s open texture, Mark Wilson’s patches and facades, Sneed’s structuralism, and Paul Thagard’s conceptual revolutions. (...) -/- In order to analyze and compare the conception of conceptual change provided by these different models, I rely on several historical reconstructions of episodes of scientific conceptual change. The historical episodes of scientific change that figure in this work include the emergence of the morphological concept of fish in biological taxonomies, the development of scientific conceptions of temperature, the Church-Turing thesis and related axiomatizations of effective calculability, the history of the concept of polyhedron in 17th and 18th century mathematics, Hamilton’s invention of the quaternions, the history of the pre-abstract group concepts in 18th and 19th century mathematics, the expansion of Newtonian mechanics to viscous fluids forces phenomena, and the chemical revolution. I will also present five different formal and informal improvements of four specific models of conceptual change. I will first present two different improvements of Carnapian explication, a formal and an informal one. My informal improvement of Carnapian explication will consist of a more fine-grained version of the procedure that adds an intermediate, third step to the two steps of Carnapian explication. I will show how this novel three-step version of explication is more suitable than its traditional two-step relative to handle complex cases of explications. My second, formal improvement of Carnapian explication will be a full explication of the concept of explication itself within the theory of conceptual spaces. By virtue of this formal improvement, the whole procedure of explication together with its application procedures and its pragmatic desiderata will be reconceptualized as a precise procedure involving topological and geometrical constraints inside the theory of conceptual spaces. My third improved model of conceptual change will consist of a formal explication of Darwinian models of conceptual change that will make vast use of Godfrey-Smith’s population-based Darwinism for targeting explicitly mathematical conceptual change. My fourth improvement will be dedicated instead to Wilson’s indeterminate model of conceptual change. I will show how Wilson’s very informal framework can be explicated within a modified version of the structuralist model-theoretic reconstructions of scientific theories. Finally, the fifth improved model of conceptual change will be a belief-revision-like logical framework that reconstructs Thagard’s model of conceptual revolution as specific revision and contraction operations that work on conceptual structures. -/- At the end of this work, a general conception of conceptual change in science and philosophy emerges, thanks to the combined action of the three layers of my methodology. This conception takes conceptual change to be a multi-faceted phenomenon centered around the dynamics of groups of concepts. According to this conception, concepts are best reconstructed as plastic and inter-subjective entities equipped with a non-trivial internal structure and subject to a certain degree of localized holism. Furthermore, conceptual dynamics can be judged from a weakly normative perspective, bound to be dependent on shared values and goals. Conceptual change is then best understood, according to this conception, as a ubiquitous phenomenon underlying all of our intellectual activities, from science to ordinary linguistic practices. As such, conceptual change does not pose any particular problem to value-laden notions of scientific progress, objectivity, and realism. At the same time, this conception prompts all our concept-driven intellectual activities, including philosophical and metaphilosophical reflections, to take into serious consideration the phenomenon of conceptual change. An important consequence of this conception, and of the analysis that generated it, is in fact that an adequate understanding of the dynamics of philosophical concepts is a prerequisite for analytic philosophy to develop a realistic and non-idealized depiction of itself and its activities. (shrink)

The ability to reason and problem‐solve in novel situations, as measured by the Raven's Advanced Progressive Matrices (RAPM), is highly predictive of both cognitive task performance and real‐world outcomes. Here we provide evidence that RAPM performance depends on the ability to reallocate attention in response to self‐generated feedback about progress. We propose that such an ability is underpinned by the basal ganglia nuclei, which are critically tied to both reward processing and cognitive control. This hypothesis was implemented in a neurocomputational (...) model of the RAPM task, which was used to derive novel predictions at the behavioral and neural levels. These predictions were then verified in one neuroimaging and two behavioral experiments. Furthermore, an effective connectivity analysis of the neuroimaging data confirmed a role for the basal ganglia in modulating attention. Taken together, these results suggest that individual differences in a neural circuit related to reward processing underpin human fluid reasoning abilities. (shrink)

Fibre suspension has garnered considerable attention in turbulent flows that are used in many industries. Solid particles, such as dust particles, notably affect the turbulent flow field in a rotational frame. In assessing their impacts, the dusty turbulent flow for fibre suspensions needs to be studied in a frame of rotation that can be substantially applied in many industries. This study, therefore, aims to build a theoretical model for the energy motion of dusty turbulent flow of fibre suspensions in (...) a rotational frame. The turbulence momentum equation was considered to formulate the model in presence of dusty fluid rotating flow of fibre suspensions. The newly derived equation was derived in second-order correlation tensors Fi,j, Wi,j, Gi,j, Si,j, Xi,j, Yi,j, Qi,j, and Ri,j at any two points in the flow domain, where the tensors were expressed as space, time, and distance functions. The developed model is a considerable improvement because it takes into account all of the potential influential parameters that could affect the motion of turbulent energy, such as dust particles, suspending particles, and rotating frame. However, the impact of these parameters on turbulence energy motion must be evaluated in order to assess the performance of turbulence systems utilized in a variety of industries, such as paper manufacturing. The present theoretical development will contribute to open up experimental and numerical research opportunities for the advancement of the industry, science, and technology. (shrink)

Reasons for taking1/2h/c 2 in cgs units as an equivalent in grams for the photon “rest mass” are given. Its numerical value of3.68×10 −48 g corresponds to the minimum mass equivalent energy for one half-cycle of an electromagnetic dipole field distribution, which is discontinuous. For the fluid models that are discussed, this field distribution corresponds somewhat to a hydrodynamic toroidal vortex which is stationary—if we use toroidal coordinates and assume that the ring origin has the radial velocity c, that (...) the gauge is defined by the ring origin diameter, and that free space is represented by a two-fluid model (the fluids oppositely charged). There are mappings which can transform such toroidal entities (photons) into spherical ones. The toroidal entities are possible candidates for the role of “hidden variables.”. (shrink)

Theories of decision-making and its neural substrates have long assumed the existence of two distinct and competing valuation systems, variously described as goal-directed vs. habitual, or, more recently and based on statistical arguments, as model-free vs. model-based reinforcement-learning. Though both have been shown to control choices, the cognitive abilities associated with these systems are under ongoing investigation. Here we examine the link to cognitive abilities, and find that individual differences in processing speed covary with a shift from (...) class='Hi'>model-free to model-based choice control in the presence of above-average working memory function. This suggests shared cognitive and neural processes; provides a bridge between literatures on intelligence and valuation; and may guide the development of process models of different valuation components. Furthermore, it provides a rationale for individual differences in the tendency to deploy valuation systems, which may be important for understanding the manifold neuropsychiatric diseases associated with malfunctions of valuation. (shrink)

We use the Tolman–Oppenheimer–Volkoff equations for a Chaplygin type fluid to study, analytically and numerically, the global behavior of static solutions of spherically symmetric objects. Two possible regimes are especially investigated. The first one is the phantom regime in which the pressure module exceeds the energy density. In this case the equator is absent and all the solutions have the geometry of a truncated spheroid with the same kind of singularity. The second case is the normal regime for which (...) we determine all the solutions, excluding the de Sitter one, corresponding to a tri-dimensional spheroidal geometry. Beyond the equator, three possible cases are considered; the first case has a closed spheroid characterized by a Schwarzschild-kind singularity with an infinite blue-shift at the south pole, the second case configuration has a regular spheroid and the third case has configuration of a truncated spheroid having a scalar curvature singularity to a finite value of the radial distance. We also compare all the geometric configurations with ones obtained in the special case of Chaplygin gas. (shrink)

The in vitro spontaneous contractions of human myometrium samples can be described using a phenomenological model involving different cell states and adjustable parameters. In patients not receiving hormone treatment, the dynamic behavior could be described using a three-state model similar to the one we have already used to explain the oscillations of intra-uterine pressure during parturition. However, the shape of the spontaneous contractions of myometrium from patients on progestin treatment was different, due to a two-step relaxation regime including (...) a latched phase which cannot be simulated using the previous model without introducing an ad hoc mechanism to account for the extra energy involved in this sustained contraction. One way to do this is to introduce an anomalous rate of ATP consumption, the biochemical reasons for which have not yet been elucidated and which cannot be mathematically simulated using our experimental data. An alternative explanation is the reduced cycling rate of actin-myosin cross-bridges known to occur during the latch-phase. Our experimental findings suggest a third possibility, namely a sol-gel transition with a specific relaxation time constant, which would maintain a significant part of the cell population in the contracted-state until the intracellular-medium returns to its normal fluid behavior. (shrink)

A model of gestural sequencing in speech is proposed that aspires to producing biologically plausible fluent and efficient movement in generating an utterance. We have previously proposed a modification of the well-known task dynamic implementation of articulatory phonology such that any given articulatory movement can be associated with a quantification of effort (Simko & Cummins, 2010). To this we add a quantitative cost that decreases as speech gestures become more precise, and hence intelligible, and a third cost component that (...) places a premium on the duration of an utterance. Together, these three cost elements allow us to derive algorithmically optimal sequences of gestures and dynamical parameters for generating articulator movement. We show that the optimized movement displays many timing characteristics that are representative of real speech movement, capturing subtle details of relative timing between gestures. Optimal movement sequences also display invariances in timing that suggest syllable-level coordination for CV sequences. We explore the behavior of the model as prosodic context is manipulated in two dimensions: clarity of articulation and speech rate. Smooth, fluid, and efficient movements result. (shrink)

Blair presumes the validity of the fluid-crystallized model throughout his article. Two comparative evaluations recently demonstrated that this presumption can be challenged. The fluid-crystallized model offers little to the understanding of the structural manifestation of general intelligence and other more specific abilities. It obscures important issues involving the distinction of pervasive learning disabilities (low general intelligence) from specific, content-related disabilities that impede the development of particular skills. (Published Online April 5 2006).

A long-standing tradition presents economic activity in terms of the flow of fluids. This metaphor lies behind a small but influential practice of hydraulic modelling in economics. Yet turning the metaphor into a three-dimensional hydraulic model of the economic system entails making numerous and detailed commitments about the analogy between hydraulics and the economy. The most famous 3-D model in economics is probably the Phillips machine, the central object of this paper.

While rules and exemplars are usually viewed as opposites, this paper argues that they form end points of the same distribution. By representing both rules and exemplars as (partial) trees, we can take into account the fluid middle ground between the two extremes. This insight is the starting point for a new theory of language learning that is based on the following idea: If a language learner does not know which phrase‐structure trees should be assigned to initial sentences, s/he (...) allows (implicitly) for all possible trees and lets linguistic experience decide which is the “best” tree for each sentence. The best tree is obtained by maximizing “structural analogy” between a sentence and previous sentences, which is formalized by the most probable shortest combination of subtrees from all trees of previous sentences. Corpus‐based experiments with this model on the Penn Treebank and the Childes database indicate that it can learn both exemplar‐based and rule‐based aspects of language, ranging from phrasal verbs to auxiliary fronting. By having learned the syntactic structures of sentences, we have also learned the grammar implicit in these structures, which can in turn be used to produce new sentences. We show that our model mimicks children’s language development from item‐based constructions to abstract constructions, and that the model can simulate some of the errors made by children in producing complex questions. (shrink)

Doctors have always thought, it seems, that the female body is more susceptible to illness than the male. Ancient medicine founded this dogma on the doctrine of elementary qualities, in attributing to woman a cold and humid constitution. As heat is the principal instrument which nature uses to produce the forces of the body and to maintain them, it must be lacking in woman, as is proved by her weakness, the softness of her limbs, her lack of external sexual organs (...) and the crudeness of her menstrual blood. If the Aristotelians and the Galenists diverge, in the Renaissance and in the XVIIth century, about the nature—fertile or not—of the “female seed,” they agree to pledge the female body to illnesses. Such a predisposition is explained by the female constitution: its coldness and its humidity, as well as retaining women's strength badly, contribute to giving them a “soft, slack body, of rare texture,” little suited to letting the body fluids, of which it is full, circulate correctly; their blood, corrupted by humidity, instead of being properly heated like it is in men, accumulates, blocks up the too small blood-vessels and causes all the illnesses of which they are the habitual victims. To this it is necessary to add the pathogenic importance of the womb, “a part of the body so sensitive and so easily upset, that its least indisposition causes an infinity of strange and almost unbearable evils.” The indispositions which affect this part of the body are always in relation to humidity or dryness, that is with “the two excrements” which it receives: sperm and menstrual blood. Whether, insufficiently impregnated by the virile liquor, “it mounts to the liver and other higher parts of the body to suck humidity from them until it becomes moist,” or it retains for an abnormally long time the seed, which decays inside it; or the periods are suppressed, or on the other hand they are produced too often; all womens illnesses are a question of impeded or excessive discharge. (shrink)

Modern microscopic theory is employed to construct a powerful analytical algorithm that permits a clear description of characteristic features of strongly correlated quantum fluids in thermodynamic equilibrium. Using recently developed formal results we uncover an intricate relationship between strongly correlated systems and free quantum gases of appropriately defined constituents. The latter entities are precisely defined renormalized bosons or fermions. They carry all the information contained in the statistical correlations of the strongly interacting many-particle system by virtue of their effective masses. (...) The mass of such a renormalized boson or fermion depends in a specific form on temperature, bulk particle number density of the many-body system, and eventually on momentum. Due to these properties the renormalized bosons and fermions determine in particular the location and nature of the transition to non-normal phases. (shrink)

Suicide is a public health problem which will require an integrated cross-sector approach to help reduce prevalence rates. One strategy is to include the legal system in a more integrated way with suicide prevention efforts. Caine explored a public health approach to suicide prevention, depicting risk factors across the socio-ecological model. The purpose of this paper is to examine laws that impact suicide prevention at the individual, relational, community, and societal levels. These levels are fluid, and some interventions (...) will fall between two, such as a community-level approach to training that enhances provider-patient relationships. At the individual level, we will review laws to improve screening requirements across systems. At the relational level, we note interventions with couples having conflict, such as protection orders and access to attorney consultations, which have been known to be injury prevention mechanisms. At the community level, we discuss legislation that recommends suicide prevention efforts for key individuals working as frontline providers in the medical and educational systems. At the societal level, we explore public awareness campaigns that target stigma reduction for those suffering from mental health burden and enhance linkage to care. The article closes with the discussion that laws are good, but their implementation is essential. (shrink)

In introducing his argument - which resumes and develops the philosophical analysis of the phenomenon of globalisation advanced in his book Westward Passage (forthcoming from Verso, London-New York) - Giacomo Marramao takes the film Babel, by the Mexican director Alejandro Gonzáles Iñárritu, as the point of departure for his discussion: the film depicts the globalised world as a complex space at once interdependent and differentiated in character, constituted like a mosaic, composed of a multiplicity of "asynchronic" ways and forms of (...) life which are brought together by the manifold flux of events that traverse them. This cinematographic depiction perfectly captures the disconcerting bi-logic of globalisation: the logic through which the mix of the global market and of digital technologies operating in "real time" generates an increasing diaspora of identities. The Babel of our contemporary world thereby reveals itself as a kind of planetary extension of the world of Kakania described by Robert Musil: a cacophonous compendium of proliferating and mutually untranslatable languages. In order to conceptualise, and produce a suitably fluid and dynamic account, of this new "world picture," we must not only dissolve the spurious dilemma between universalism and relativism, but move beyond the current impasse encouraged by a normative political philosophy which tends to reify "cultural identities" and "struggles for recognition" by treating these as givens rather than as problems. The philosophical approach pursued in the following discussion attempts to liberate the concept of "the universal" - despite the etymology of the word - from the logic of the reductio ad unum, and apply it instead to the realm of multiplicity and difference. Developing a double phenomenology of the increasingly homogenising phenomenon of the market on the one hand and of the internally conflicted pandemic of identitarian and communitarian approaches on the other, the author indicates a variety of universalising tendencies whose potential can only fully be evaluated in the context of a new theory and practice of translation. Marramao's proposal for a universalism of difference is predicated on the failure of the two principal models of "democratic" inclusion that have previously been attempted in the West: the republican or assimilationist model (that of a Republique founded upon what could be called a universalism of indifference) and the "strong" multiculturalism model (the so-called Londonistan model that derives from a mosaic of differences that also provides fertile ground for the growth of fundamentalist ideas). But to advance beyond the antagonistic complicity generated by this dilemma calls for a re-enchantment of the political: the only way in which we may be able to read the prognostic signs of our present. (shrink)

. Through examining a case study of a major fluids modelling code, this paper charts two key properties of software as a material for building models. Scientific software development is characterized by piecemeal growth, and as a code expands, it begins to manifest frustrating properties that provide an important axis of motivation in the laboratory. The first such feature is a tendency towards brittleness. The second is an accumulation of supporting technologies that sometimes cause scientists to express a frustration with (...) the bureaucracy of highly regulated working practices. Both these features are important conditions for the pursuit of research through simulation. (shrink)

We examine one of the well-known mathematical works of Abraham bar Ḥiyya: Ḥibbur ha-Meshiḥah ve-ha-Tishboret, written between 1116 and 1145, which is one of the first extant mathematical manuscripts in Hebrew. In the secondary literature about this work, two main theses have been presented: the first is that one Urtext exists; the second is that two recensions were written—a shorter, more practical one, and a longer, more scientific one. Critically comparing the eight known copies of the Ḥibbur, we show that (...) contrary to these two theses, one should adopt a fluid model of textual transmission for the various manuscripts of the Ḥibbur, because neither of these two theses can account fully for the changes among the various manuscripts. We hence offer to concentrate on the typology of the variations among the various manuscripts, dealing with macro-changes (such as omissions or additions of proofs, additional appendices or a reorganization of the text itself), and micro-changes (such as textual and pictorial variants). (shrink)

Within the fields of social medicine and the medical humanities, chronic illness is acknowledged not just as an individually but as a socially transformative experience. The proliferation of published ‘illness narratives’ in recent years attests to the socially compelling nature of this particular story of transformation. Indeed, illness narratives have, in the past decade or so, become a rich source of interest in sociological and medical anthropological work for their capacity to map the material transformation of person to patient, of (...) an assumed to a newly fluid model of subjectivity. Their significance is particularly visible in the cultural context of the west, where more people live both to be diagnosed with chronic illnesses (such as cancer) and to survive them. With a focus on two recently published Australian works, Eating the Underworld: A Memoir in Three Voices (2001), by the psychologist Doris Brett, and Tiger’s Eye: A Memoir (2001), by the historian Inga Clendinnen, this paper will consider how the illness experience marks a transformation of embodied subjectivity that, in turn, triggers transformations of other kinds. These works have quite different intents, but they provide models for exploring how physical and individual transformation through illness becomes the occasion for reconsidering the body of history, and of the resonances of history in social memory. (shrink)

The role of mathematics in scientific practice is too readily relegated to that of formulating equations that model or describe what is being investigated, and then finding solutions to those equations. I survey the role of mathematics in: 1. Exact solutions of differential equations, especially conformal mapping; and 2. Simulations of solutions to differential equations via numerical methods and via agent-based models; and 3. The use of experimental models to solve equations (a) via physical analogies based on similarity of (...) the form of the equations, such as Prandtl’s soap-film method, and (b) the method of physically similar systems. Two major themes emerge: First, the role of mathematics in science is not well described by deduction from axioms, although it generally involves deductive reasoning. Creative leaps, the integration of experimental or observational evidence, synthesis of ideas from different areas of mathematics, and insight regarding analogous forms are required to find solutions to equations. Second, methods that involve mappings or transformations are in use in disparate contexts, from the purely mathematical context of conformal mapping where it is mathematical objects that are mapped, to the use of concrete physical experimental models, where one concrete thing is shown to correspond to another. (shrink)

Dissociative symptoms are notorious for their enigmatic, disparate nature encompassing excessive daydreaming, memory problems, absentmindedness, and impairments and discontinuities in perceptions of the self, identity, and the environment. Recent studies (e.g., Koffel & Watson, 2009) have linked dissociative symptoms to vivid dreaming, nightmares, and objective sleep parameters (e.g., lengthening of REM sleep) for discussion, see (Van der Kloet et al., 2013). Germane to this link between dissociative symptomology and sleep, is the idea that in dissociative individuals, the waking state as (...) compared to REM sleep may be marked by an increase in “fluid” and hyperassociative thinking. Against this background, we invited contributions in the following areas: 1) a progressive and enduring de-differentation of wake and dream states of consciousness eventually results in schizophrenia (Llewellyn, 2011); a lesser degree of de-differentiation may have implications for dissociative symptoms; 2) sleep disturbances are not only linked to dissociation but to memory fragmentation also, further fuelling both dissociation and other manifestations of psychopathology; 3) sleep, memory and psychopathologies have complex interlinkages. Our summary below, relates the contributions to our topic to these areas. The contributing articles also give a comprehensive overview on current directions and challenges in these research fields.First, Soffer-Dudek elucidates why heightened sleep experiences (vivid dreams, nightmares, hypnagogic hallucinations) might be particularly associated with psychopathology. She explains how various psychopathologies may represent de-differentiation of the waking and dreaming states through intrusions of wake-like consciousness into sleep and dream-like cognition into wake. With regard to de-differentiation, she discusses theories of transliminality (‘thin boundaries between consciousness states’) and dissociation as potential mechanisms. Lucid dreaming is a hybrid state where wake-like cognition suffuses REM sleep/dreaming (Voss et al. 2009). Mota and colleagues compared the spontaneous occurrence of lucid dreaming in patients with psychotic symptoms (25 with schizophrenia and 20 with bipolar disorder) and 28 non-psychotic subjects. They found lucid dreaming was associated with psychosis- giving some support to the hypothesis of a link between state de-differentiation and psychopathology. In a methodological note, Ribeiro et al, having studied the prevalence of lucid dreaming using two questionnaires, show that the type of methodology used in lucid dreaming studies may have an effect upon their findings. Poerio et al state that both research and theory points to dissociation being engendered by the intrusion of dream-like mentation into waking consciousness. To extend this idea they examine the role of sleep and daydreaming as potentiating states for subsequent dissociation in depersonalization/derealization disorder (DDD). They show the occurrence and content of daydreams may act as potentiating states for heightened, in the moment, dissociation. Sleep paralysis is a dissociated state where a heightened level of wake-like alertness coexists with muscle atonia. Rodrigez de Sa and Mota-Rolim take a broad interdisciplinary perspective on sleep paralysis through reviewing its occurrence in Brazilian folklore by exploring the “Pisadeira” with a sleep science approach and link this with the field of history and art.There is now substantial evidence that active memory processing continues during sleep (see, for example, Rasch and Born (2013)) and dreaming may be involved (Llewellyn, 2013). De-differentiation of the wake, sleep and dream states would disrupt this memory processing fuelling dissociation and other psychopathologies. Horton presents an overview of discontinuity of consciousness in both wake and sleep, focusing on the processes of sleep-dependent memory consolidation and fragmentation. Nakagawa et al focus specifically on working memory and the relation with sleep. With their article, they are the first to investigate differences between verbal working memory (VWM) and visuospatial working memory (VSWM) related to daytime nap duration, nap frequency, and dream content recall frequency (DCRF). They discuss sex-related differences in the effects of sleep habits on VMW and VSWM and ascribe this to differences in underlying neural correlates, and effectiveness of sleep habits in males and females. Rosales-Lagarde and colleagues related to emotional memory by designing an extended International Affective Picture System (IAPS) instrument to measure bizarreness and show some interesting age and gender disparities. Finally, several authors took a developmental approach through focusing on sleep, memory and psychopathology in adolescents. Wang and colleagues show the relation between children and adolescents’ mental health and sleep problems in a 10-year longitudinal trial, and find anxiety, depression, attention problems and aggressive behaviour during childhood to be important predictors for later sleep problems. Importantly, sleep problems are also predictive of behavioural difficulties later in life. Nader, Murkar, and Smith investigated changes in sleep in adolescents between 12 and 19 years old following procedural task training and found that contrary to earlier work, there were no changes in sleep spindle density. Interestingly, participants who successfully learned the task showed no changes in their sleep stage proportions, but participants who were not successful showed a decrease in the proportion of Stage 2 and increases in both SWS and REM sleep, which is in line with the two stage model of sleep and memory by Smith et al. (2004).The self and the world during dreaming differ. The perceived world during waking depends on making sense of external sensory input, which engenders a strong sense of external reality in which the ‘self and its inner-world’ exists. Self-organizing during waking and dreaming enables integration of the self and the world in both states. It is noteworthy, that within this research topic so many novel themes have emerged and new questions and speculations have been posed with regards to relations among unusual sleep experiences – specifically lucid dreaming -, dissociation, psychosis, and memory. It brings together a richness of research by combining fields that originally have worked in isolation from each other. (shrink)

We succeed to say something on the identities of when μ > θ > cf with μ strong limit θ-compact or even μ is limit of compact cardinals.

My aim is to relate Søren A. Kierkegaard’s early theory of stages as described basically in “Either-Or” to the theory of interest underlying the two process model of cognition of the Canadian psychologist Keith E. Stanovich with regard to the question of the highest formal goal we can pursue in our life. On the basis of Stanovich’s distinction between type 1 and type 2 processing and Kierkegaard’s distinction between an esthetical and an ethical stage of life, I argue for (...) an extension of Stanovich’s understanding of the goal structure of type 2 processing, for Kierkegaard’s ethical stage of life being a natural expression of our cognitive faculties and for a critical approach to Kierkegaard's idea of a religious stage as hinted at in “Fear and Trembling”. (shrink)

Studies have shown that as MRI T2 relaxation time lengthens there is a shift toward more unbound or “free-water” and less partitioning of the protein/lipid molecules per unit volume. A shift toward less water partitioning or lengthened MRI T2 relaxation time is linearly related to reduced high frequency EEG amplitude, reduced short distance EEG coherence, increased long distance EEG coherence, and reduced cognitive functioning (Thatcher et al. 1998a; 1998b).

Two theme–setting quotations introduce this essay—that of Yeats's falcon, deaf to the falconer's call, adrift in space above the blood–dimmed tide, counterpoised to Pierre Teilhard de Chardin's call to abandon old nationalistic prejudices and build the earth. With primary references to the thought of Teilhard, along with, among others, to Ewert Cousins, Andrew M. Greeley, Karl Jaspers, Marshall McLuhan, Ilya Prigogine, Karl Rahner, Leonard Swidler, David Tracy, and Alfred North Whitehead, I argue that the most crucial intellectual paradigm shift of (...) the twenty–first century will challenge humanity to take the turn from uncritical attachment to rigid absolutism or atomistic fragmentation toward a sense of open–ended, off–centered centeredness and fluid connections—from a static to a dynamic model of reality. Central to my argument is the Teilhardian reinterpretation of the Christian metaphors of creation, fall, incarnation, salvation, and the eschaton in the evolutionary terms of the emergence of cosmic consciousness from the chrysalis of the world of the past—from chaos to order, from biosphere via noosphere to theosphere. Facilitated by the exponential growth of populations, collaborative research, science, technology, and global communication (most dramatically manifested by the Internet), this emergent understanding of what it means to be human can, first, foster the awareness that in humanity evolution has become conscious of itself, and then, gradually, precipitate the formation of “the global village” (the mystical body of Christ), as respectful dialogue replaces diatribe and the dualistic pugilism of Samuel Huntington's “Clash of Civilizations” is gradually transformed into a nonadversarial mentality that values shared humanity and a common purpose. Thus, eons hence, empowered by love–energy, the transmutation of the human into the ultra–human can take the ultimate quantum leap into a yet higher dimension where spirit/energy is no longer in need of flesh/mass, and Earth can be safely left behind. (shrink)

Pixelism is the combination of three metaphysical thesis, namely a radical form of exdurantism, mereological nihilism and counterpart theory. Pixelism is a theory that evaluates all the metaphysical phenomena of persistence, composition and modality in a homogeneous and consistent manner. In a pixel world, there is no identity over time and over possible worlds and nothing persists over more than an instant or a world. Entities can be univocally identified by a five-coordinates system (the three spatial dimensions, the temporal one (...) and the possible worlds), and their relation is a counterpart relation both in different worlds and at different times or different regions of space. In this paper I will provide two models for pixelism: the first one takes pixels to be hypercubes, i. e. four-dimensional cubes, the acceptance of which is conditional on the acceptance of extended simples. The second one considers pixels as points in a four-dimensional space. (shrink)

We deal here with colorings of the pair , when μ is a strong limit and singular cardinal. We show that there exists a coloring c with no refinement. It follows that the properties of colorings of when μ is singular differ in an essential way from the case of regular μ.

Experimental activity is traditionally identified with testing the empirical implications or numerical simulations of models against data. In critical reaction to the ‘tribunal view’ on experiments, this essay will show the constructive contribution of experimental activity to the processes of modeling and simulating. Based on the analysis of a case in fluid mechanics, it will focus specifically on two aspects. The first is the controversial specification of the conditions in which the data are to be obtained. The second is (...) conceptual clarification, with a redefinition of concepts central to the understanding of the phenomenon and the conditions of its occurrence. (shrink)

In this work, we reconstruct the cosmological unified dark fluid model proposed previously by Elkhateeb (Astrophys Space Sci 363(1):7, 2018) in the framework of _f_(_R_) gravity. Utilizing the equivalence between the scalar-tensor theory and the _f_(_R_) gravity theory, the scalar field for the dark fluid is obtained, whence the _f_(_R_) function is extracted and its viability is discussed. The _f_(_R_) functions and the scalar field potentials have then been extracted in the early and late times of asymptotically (...) de Sitter spacetime. The ability of our function to describe early time inflation is also tested. The early time scalar field potential is used to derive the slow roll inflation parameters. Our results of the tensor-to-scalar ratio _r_ and the scalar spectral index \(n_s\) are in good agreement with results from Planck-2018 TT+TE+EE+lowE data for the model parameter \(n > 2\). (shrink)

It is well known that working memory performance changes with age. Two recent computational models of working memory, TBRS* and SOB-CS, developed from young adults WM performances are opposed regarding the postulated causes of forgetting, namely time-based decay and interference for TBRS* and SOB-CS, respectively. In the present study, these models are applied on a set of complex span data produced by young and older adults. As expected, these models are unable to account for the older adult data. An investigation (...) on the effect of the main parameters of these models showed that the poorer performance of older adults does not come from a weaker encoding of item but rather from difficulties during the free time that immediately follows each distractor, as well as from a higher level of confusion between items. These results are discussed with respect to the current theories of working memory and aging. (shrink)

I argue that a two-dimensional model of social objects is uniquely positioned to deliver explanations for some of the puzzling metaphysical features of words. I consider how a type-token model offers explanations for the metaphysical features of words, but I give reasons to find the model wanting. In its place, I employ an alternative model from social ontology to explain the puzzling data and questions that are generated from the metaphysical features of words. In the end (...) I chart a new path that foregrounds the agent-dependence and social conditions for word kinds. (shrink)

This article treatsMachiavelli's exploration of the two versions (Herodotean and Xenophontic) of Cyrus in his Prince and Discourses. This article is novel insofar as most commentators on Machiavelli do not treat the fact that there are two Cyruses and thatMachiavelli uses them to make different points about princely and republican leadership. The Xenophontic Cyrus serves as an example of humanity--albeit a complicated example -- while the Herodotean Cyrus serves as an example of harshness. This article aims to show how a (...) combination of the Cyruses' humanity and harshness makes for a better model for republican leaders to imitate, and urges a reeducation of a republican leader like Scipio, who was inclined only to follow the humane path of the Xenophontic Cyrus. (shrink)

This paper shows that a simple two-stage approach to handle non-local dependencies in Named Entity Recognition (NER) can outperform existing approaches that handle non-local dependencies, while being much more computationally efficient. NER systems typically use sequence models for tractable inference, but this makes them unable to capture the long distance structure present in text. We use a Conbel.

This article analyzes approaches to nondeterminacy that suggest that one can make justified choices when primary criteria fail to fully determine a best alternative by introducing a secondary criterion. It is shown that these approaches risk violating Basic Contraction Consistency. Some ways of adjusting two-step models in order to protect against this are addressed, and it is suggested that proponents of two-step models should adopt formal conditions which qualify what counts as a permissible secondary criterion that resemble supervaluationist conditions that (...) qualify what counts as admissible precisifications of vague terms. (shrink)

The current consensus is that most natural categories are not organized around strict definitions (a list of singly necessary and jointly sufficient features) but rather according to a family resemblance (FR) principle: Objects belong to the same category because they are similar to each other and dissimilar to objects in contrast categories. A number of computational models of category construction have been developed to provide an account of how and why people create FR categories (Anderson, 1990; Fisher, 1987). Surprisingly, however, (...) only a few experiments on category construction or free sorting have been run and they suggest that people do not sort examples by the FR principle. We report several new experiments and a two‐stage model for category construction. This model is contrasted with a variety of other models with respect to their ability to account for when FR sorting will and will not occur. The experiments serve to identify one basis for FR sorting and to support the two‐stage model. The distinctive property of the two‐stage model is that it assumes that people impose more structure than the examples support in the first stage and that the second stage adjusts for this difference between preferred and perceived structure. We speculate that people do not simply assimilate probabilistic structures but rather organize them in terms of discrete structures plus noise. (shrink)