986 resultados para postulates and axioms
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We model experience-dependent plasticity in the cortical representation of whiskers (the barrel cortex) in normal adult rats, and in adult rats that were prenatally exposed to alcohol. Prenatal exposure to alcohol (PAE) caused marked deficits in experience-dependent plasticity in a cortical barrel-column. Cortical plasticity was induced by trimming all whiskers on one side of the face except two. This manipulation produces high activity from the intact whiskers that contrasts with low activity from the cut whiskers while avoiding any nerve damage. By a computational model, we show that the evolution of neuronal responses in a single barrel-column after this sensory bias is consistent with the synaptic modifications that follow the rules of the Bienenstock, Cooper, and Munro (BCM) theory. The BCM theory postulates that a neuron possesses a moving synaptic modification threshold, θM, that dictates whether the neuron's activity at any given instant will lead to strengthening or weakening of its input synapses. The current value of θM changes proportionally to the square of the neuron's activity averaged over some recent past. In the model of alcohol impaired cortex, the effective θM has been set to a level unattainable by the depressed levels of cortical activity leading to “impaired” synaptic plasticity that is consistent with experimental findings. Based on experimental and computational results, we discuss how elevated θM may be related to (i) reduced levels of neurotransmitters modulating plasticity, (ii) abnormally low expression of N-methyl-d-aspartate receptors (NMDARs), and (iii) the membrane translocation of Ca2+/calmodulin-dependent protein kinase II (CaMKII) in adult rat cortex subjected to prenatal alcohol exposure.
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We propose a unifying picture where the notion of generalized entropy is related to information theory by means of a group-theoretical approach. The group structure comes from the requirement that an entropy be well defined with respect to the composition of independent systems, in the context of a recently proposed generalization of the Shannon-Khinchin axioms. We associate to each member of a large class of entropies a generalized information measure, satisfying the additivity property on a set of independent systems as a consequence of the underlying group law. At the same time, we also show that Einstein's likelihood function naturally emerges as a byproduct of our informational interpretation of (generally nonadditive) entropies. These results confirm the adequacy of composable entropies both in physical and social science contexts.
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Residuated lattices, although originally considered in the realm of algebra providing a general setting for studying ideals in ring theory, were later shown to form algebraic models for substructural logics. The latter are non-classical logics that include intuitionistic, relevance, many-valued, and linear logic, among others. Most of the important examples of substructural logics are obtained by adding structural rules to the basic logical calculus
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The purpose of the current paper is to present an integrative definition of coaching effectiveness and expertise that is both specific and conceptually grounded in the coaching, teaching, positive psychology, and athletes' development literature. The article is organized into six sections. The first section is used to situate the proposed definition in the predominant conceptual models of coaching. The second, third, and fourth sections provide detailed discussion about each of the three components of the proposed definition of coaching effectiveness: (a) coaches' knowledge, (b) athletes' outcomes, and (c) coaching contexts. The proposed definition is presented in the fifth section along with a clarification of common terminology and guiding postulates. The final section includes implications for practice and research.
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INTRODUCTION In the current times of multifaceted crisis, nationalism looks, more than ever, like a positive and necessary feeling. It seems both natural and indispensable if we are to have viable political and social institutions that meet the needs and preferences of all citizens. The following paper contests this vision. Its criticism of nationalism is directed not only at its national forms, but also at any defence of collective identity based on the same model, such as the various forms of European nationalism. Furthermore, the same overriding criticism can be made of different kinds of nationalism, regardless of their more or less open and progressive political content. In order to ground our argument theoretically and practically, we will try to show that nationalism is always potentially harmful to individual rights, and unnecessary for the maintenance of a just social and political system. We will thus oppose any acritical defence of the intrinsic value of a specific community and the belief in its artificial homogeneity. The historical construction of a supposedly homogeneous community, and the insistence on its values, which are perceived as superior and binding, facilitate the absorption of the individual into the collective. As we will explain further in more details, this holistic approach is typical of communitarian approaches. In that respect, it does not really matter whether they appeal to passion or to reason, to some irrational binding features of the community or to more rational political aspects of a common identity. The main problem in nationalism is not the emotion it can trigger, it is not even its reliance on particular values. What makes nationalism problematic is, firstly, that it tends to overlook the intrinsically divisive and contradictory nature of individual and collective interests in unjust societies; secondly, that it attributes an intrinsic superiority to a particular community over others; and thirdly, that it sees politics as a means to promote the interests, values or identity of that community. As an alternative, we will very briefly advocate a cosmopolitan approach that grounds political legitimacy in a demanding approach to individual freedom, rather than in a shared collective identity. However, even if only briefly, we will also carefully distinguish our own vision of cosmopolitanism from those commonly put forward. Frequently, cosmopolitan perspectives entangle their identity frameworks with concrete political projects, without clearly explaining how the latter derive from the former. Our approach to cosmopolitanism, on the other hand, is, first and foremost, a critical vision of all communitarian postulates according to which politics should be based on some form of collective identity. Thus, we insist on the conceptual distinction between a general stance on identity issues and the more practical political ideology one stands for. In a subsequent step, we link this cosmopolitan framework with a progressive approach to individual rights. Because of our demanding approach to individual freedom, our cosmopolitanism goes hand in hand with a revival of identity-free sovereignty. It is therefore distinct from the severe condemnation of sovereignty often found in most mainstream cosmopolitan positions. Finally, instead of the frequent confusion found in public discourses and in the literature between ideals and reality, our position acknowledges the deep gulf separating these two dimensions. It therefore sketches out very general strategic principles to bring normative ideals closer to political reality.
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I will start by discussing some aspects of Kagitcibasi’s Theory of Family Change: its current empirical status and, more importantly, its focus on universal human needs and the consequences of this focus. Family Change Theory’s focus on the universality of the basic human needs of autonomy and relatedness and its culture-level emphasis on cultural norms and family values as reflecting a culture’s capacity for fulfilling its members’ respective needs shows that the theory advocates balanced cultural norms of independence and interdependence. As a normative theory it therefore postulates the necessity of a synthetic family model of emotional interdependence as an alternative to extreme models of total independence and total interdependence. Generalizing from this I will sketch a theoretical model where a dynamic and dialectical process of the fit between individual and culture and between culture and universal human needs and related social practices is central. I will discuss this model using a recent cross-cultural project on implicit theories of self/world and primary/secondary control orientations as an example. Implications for migrating families and acculturating individuals are also discussed.
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Records of mean sortable silt and planktonic foraminiferal preservation from the Ceará Rise (western equatorial Atlantic) and from the Caribbean are presented to analyze the Pliocene (3.5-2.2 Ma) to Pleistocene (1.6-0.3 Ma) evolution of near-bottom current strength and the carbonate corrosiveness of deep water. During the mid-Pleistocene climate transition (~1 Ma) a drastic decrease in glacial bottom current strength and an increase in carbonate corrosiveness is registered, demonstrating a substantial decrease in the glacial contribution of the Lower North Atlantic Deep Water (LNADW) to the Atlantic Ocean. Also, an increased sensitivity to eccentricity orbital forcing is registered after the MPT. By contrast, carbonate preservation increases considerably in the deep Caribbean in response to a strong and persistent stable contribution of Upper North Atlantic Deep Water (UNADW). We found evidence for the strongest and most stable circulation within the LNADW cell during the Northern Hemisphere cooling period between ~3.2 and 2.75 Ma. This is in agreement with the 'superconveyor model' which postulates that the highest NADW production took place prior to ~2.7 Ma. A considerable decrease in bottom current strength and planktonic foraminiferal preservation is observed synchronous with the first occurrence of large-scale continental ice sheets in the Northern Hemisphere. This documents the final termination of the 'superconveyor' at ca. 2.75 Ma. However, our data do not support a 'superconveyor' in the interval between 3.5 and 3.2 Ma when high-amplitude fluctuations in bottom current flow and preservation in planktonic foraminifera are observed. Because of the great sensitivity of NADW production to changes in surface water salinity, we assume that the high-amplitude fluctuations of LNADW circulation prior to ~3.2 Ma are linked to changes in the Atlantic salinity budget. After 2.75 Ma they are primarily controlled by ice-sheet forcing. In contrast to the stepwise deterioration of planktonic foraminiferal preservation in the western deep Atlantic, a trend toward better preservation from the Pliocene to Pleistocene is observed in the deep Caribbean. This indicates a long-term increase in the contribution of UNADW to the Atlantic Ocean.
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Benthic foraminifera from 24 DSDP/ODP sites were investigated to assess their global horizontal and vertical distribution in the deep-sea environment at the end of the Cretaceous period. The samples analyzed are from the late Maastrichtian and within the planktic foraminiferal Abathomphus mayaroensis Zone from a wide range of oceans and paleolatitudes, including the low-latitude Sites 10 and 384 (Atlantic Ocean), 47, 171, 305, and 465 (Pacific Ocean), the mid-latitude Sites 20, 111, 356, 363, 516, 525, 527, 548, and 605 (Atlantic Ocean), 216, 217, and 758 (Indian Ocean), and the high-latitude Sites 208 (Pacific Ocean), 689,698,700,738 and 750 (Southern Ocean). Correspondence analysis, based on the 75 most common taxa, shows a clear biogeographic trend along the first correspondence axis by arranging the sites in paleolatitudinal order. The assemblages from the Tethyan Realm (i.e., low latitudes) are marked by abundant heavily calcified buliminids (such as Bulimina incisa, B. trinitatensis, B. velascoensis, and Reussella szajnochae) and Aragonia spp., whereas high-latitude faunas are characterized by abundant Alabamina creta, Gyroidinoides quadratus, and Pullenia coryelli. The results indicate that the faunas at low and high latitudes, respectively, were influenced by quite different environmental conditions. This is based on the much higher abundance of infaunal morphotypes at low and mid latitudes compared to high latitudes, suggesting that the biogeographic trend found in the data set coincides with the trophic regime at the various sites. The results also provide support for the hypothesis that postulates two simultaneous sources and mechanisms for deep-water formation during the Late Cretaceous, including warm, saline deep water produced by evaporation at low (equatorial) latitudes in contrast to the formation of cold deep waters at high (southern) latitudes.
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Mode of access: Internet.
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Philosophy: its relation to life and education.--The idealism of Spinoza.--Recent discussion in materialism.--Professor Watson on reality and time.--The cosmic and the moral.--Psychology past and present.--The postulates of physiological psychology.--The origin of volition in childhood.--Imitation: a chapter in the natural history of consciousness.--The origin of emotional expression.--The perception of external reality.--Feeling, belief, and judgment.--Memory for square size.--The effect of size-contrast upon judgments of position in the retinal field.--An optical illusion.--New questions in mental chronometry.--Types of reaction.--The "type-theory" of reaction.--The psychology of religion.--Shorter philosophical papers.--Shorter literary papers.
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Thesis (Ph.D.)--University of Washington, 2016-06
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Construction of an international index of standards of living, incorporating social indicators and economic output, typically involves scaling and weighting procedures that lack welfare-economic foundations. Revealed preference axioms can be used to make quality-of-life comparisons if we can estimate the representative household's production technology for the social indicators. This method is applied to comparisons of gross domestic product (GDP) and life expectancy for 58 countries. Neither GDP rankings, nor the rankings of the Human Development Index (HDI), are consistent with the partial ordering of revealed preference. A method of constructing a utility-consistent index incorporating both consumption and life expectancy is suggested. (C) 2003 Elsevier Science B.V. All rights reserved.
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Alzheimer's disease (AD) is the most common form of dementia, accounting for 60-70% of cases in subjects over 65 years of age. Several postulates have been put forward that relate AD neuropathology to intellectual and functional impairment. These range from free-radical-induced damage, through cholinergic dysfunction, to beta-amyloid-induced toxicity. However, therapeutic strategies aimed at improving the cognitive symptoms of patients via choline supplementation, cholinergic stimulation or beta-amyloid vaccination, have largely failed. A growing body of evidence suggests that perturbations in systems using the excitatory amino acid L-glutamate (L-Glu) may underlie the pathogenic mechanisms of (e.g.) hypoxia-ischemia, epilepsy, and chronic neurodegenerative disorders such as Huntington's disease and AD. Almost all neurons in the CNS carry the N-methyl-D-aspartate (NMDA) subtype of ionotropic L-glutamate receptors, which can mediate post-synaptic Ca2+ influx. Excitotoxicity resulting from excessive activation of NMDA receptors may enhance the localized vulnerability of neurons in a manner consistent with AD neuropathology, as a consequence of an altered regional distribution of NMDA receptor subtypes. This review discusses mechanisms for the involvement of the NMDA receptor complex and its interaction with polyamines in the pathogenesis of AD. NMDA receptor antagonists have potential for the therapeutic amelioration of AD. (C) 2004 Elsevier Ltd. All rights reserved.
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Rhizoctonia solani AG-2-2 was isolated from wilting and dying plants of sulla ( Hedysarum coronarium), which is currently being assessed in eastern and southern Australia for its potential as a pasture and forage legume. Infected plants in the field had extensive rotting of the taproot, lateral roots and crown. Koch's postulates were fulfilled using three inoculation methods. The disease may pose a considerable threat to the potential use of H. coronarium in the dryland, grazing farming systems of Australia, with resistance offering the most viable option for minimising its impact.
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This paper begins by exploring four different possible forms of relationship between economics and psychology, which have different connotations in terms of the relative status of the two disciplines. It then focuses on the future for one of these, psychological economics. After setting out the hardcore axioms and positive and negative heuristics of a research programme in psychological economics, it explores institutional and psychological barriers to the success of such a research programme in the context of both research and teaching.