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1.
Many studies have demonstrated that the sensory and motor systems are activated during conceptual processing. Such results have been interpreted as indicating that concepts, and important aspects of cognition more broadly, are embodied. That conclusion does not follow from the empirical evidence. The reason why is that the empirical evidence can equally be accommodated by a 'disembodied' view of conceptual representation that makes explicit assumptions about spreading activation between the conceptual and sensory and motor systems. At the same time, the strong form of the embodied cognition hypothesis is at variance with currently available neuropsychological evidence. We suggest a middle ground between the embodied and disembodied cognition hypotheses--grounding by interaction. This hypothesis combines the view that concepts are, at some level, 'abstract' and 'symbolic', with the idea that sensory and motor information may 'instantiate' online conceptual processing.  相似文献   

2.
It is widely accepted that numerous cell types respond to mechanical stimuli, yet there is no general agreement as to whether particular cells respond directly to stress, strain, strain-rate, strain-energy, or other mechanical quantities. By recalling the definitions of the mathematical (not physical) concepts of stress and strain, it is suggested herein that cells cannot respond directly to these continuum metrics or to quantities derived from them--mechanistic models will need to be based on more fundamental quantities, as, for example, inter-atomic forces or conformational changes of the appropriate molecules. Nonetheless, the concepts of stress and strain should continue to play an important role in mechanobiology, both in the identification of empirical correlations and in the development of phenomenological constitutive models, each of which can contribute to our basic understanding as well as help in the design of future experiments and some clinical interventions. It is important to remember, therefore, that empirical correlations and most constitutive relations in continuum mechanics do not seek to model the actual physics--rather, their utility is in their predictive capability, which is often achieved via different relations in terms of different metrics for the same material under different conditions. Hence, with regard to quantifying cellular responses to mechanical stimuli, we must delineate between the identification of fundamental mechanisms and the formulation of phenomenological correlations, the latter of which only requires convenient metrics that need not be unique or physical.  相似文献   

3.
Seminal works of the 1960s on open systems by Arthur Koestler, Ramon Margalef and Richard Vollenweider are interrelated here, with many other works on the science of aquatic ecosystems, in a heuristic model of selected manifestations and transformations of the aquatic ecosystems of the rivers and lakes of the Great Lakes — St. Lawrence River Basin, here perceived as a single loosely-integrated ecosystem. Our empirical model is in the form of a tentative generalization of a set of features and events — large-scale with respect to time and space — in these aquatic ecosystems, with some suggestions of recent relevant theoretical concepts from post-normal studies of complex phenomena. Our work may be a step toward a more comprehensive, bioregional, heuristic model of the Basin to include the aquatic and terrestrial, as well as the natural and cultural ecosystemic features.  相似文献   

4.
Species‐level taxonomy derives from empirical sources (data and techniques) that assess the existence of spatiotemporal evolutionary lineages via various species “concepts.” These concepts determine if observed lineages are independent given a particular methodology and ontology, which relates the metaphysical species concept to what “kind” of thing a species is in reality. Often, species concepts fail to link epistemology back to ontology. This lack of coherence is in part responsible for the persistence of the subspecies rank, which in modern usage often functions as a placeholder between the evolutionary events of divergence or collapse of incipient species. Thus, prospective events like lineages merging or diverging require information from unknowable future information. This is also conditioned on evidence that the lineage already has a detectably distinct evolutionary history. Ranking these lineages as subspecies can seem attractive given that many lineages do not exhibit intrinsic reproductive isolation. We argue that using subspecies is indefensible on philosophical and empirical grounds. Ontologically, the rank of subspecies is either identical to that of species or undefined in the context of evolutionary lineages representing spatiotemporally defined individuals. Some species concepts more inclined to consider subspecies, like the Biological Species Concept, are disconnected from evolutionary ontology and do not consider genealogy. Even if ontology is ignored, methods addressing reproductive isolation are often indirect and fail to capture the range of scenarios linking gene flow to species identity over space and time. The use of subspecies and reliance on reproductive isolation as a basis for an operational species concept can also conflict with ethical issues governing the protection of species. We provide a way forward for recognizing and naming species that links theoretical and operational species concepts regardless of the magnitude of reproductive isolation.  相似文献   

5.
The purposes of this article are embodied in three questions central to the development of symbolic anthropology. How does one identify the alleged symbolic message in public rituals, and does this meaning have some sort of empirically demonstrable analogue in the minds of the actors, or consequences for their behavior? Second, can these questions be answered by a method of interpreting symbols that is empirical and that utilizes clearly specified and replicable procedures? Finally, is it legitimate to attribute symbolic meanings to behavior if the participants themselves are not aware of such meanings? If nonconscious meaning exists, does it have any effect on attitudes and motivation for behavior? Analysis of data, derived from responses to Osgood's Semantic Differential relating to concepts of gender and manners between the sexes, provides affirmative answers to the questions raised above.  相似文献   

6.
The question of how much the outcomes of cultural evolution are shaped by the cognitive capacities of human learners has been explored in several disciplines, including psychology, anthropology and linguistics. We address this question through a detailed investigation of transmission chains, in which each person passes information to another along a chain. We review mathematical and empirical evidence that shows that under general conditions, and across experimental paradigms, the information passed along transmission chains will be affected by the inductive biases of the people involved-the constraints on learning and memory, which influence conclusions from limited data. The mathematical analysis considers the case where each person is a rational Bayesian agent. The empirical work consists of behavioural experiments in which human participants are shown to operate in the manner predicted by the Bayesian framework. Specifically, in situations in which each person's response is used to determine the data seen by the next person, people converge on concepts consistent with their inductive biases irrespective of the information seen by the first member of the chain. We then relate the Bayesian analysis of transmission chains to models of biological evolution, clarifying how chains of individuals correspond to population-level models and how selective forces can be incorporated into our models. Taken together, these results indicate how laboratory studies of transmission chains can provide information about the dynamics of cultural evolution and illustrate that inductive biases can have a significant impact on these dynamics.  相似文献   

7.
Scientific discovery requires both abstract, theoretically defined concepts and discovery operations formed by sets of rules that permit the empirical detection of instances of those concepts. In this paper, I examine the ontological status of discovery operations and the tests employed to evaluate them in evolutionary biology. Attention is drawn to the distinction between nomothetic (universal, predictive) and ideographic (historical, retrodictive) discovery operations, and between complementary and exclusive discovery operations. Three types of tests of discovery operations are commonly employed in evolutionary biology. Theoretical tests aim to show that a discovery operation is inconsistent with accepted, well-corroborated, empirical theories. Empirical tests evaluate the performance of competing discovery operations in terms of their results when applied to the same empirical data sets. Philosophical tests aim to show that an operation is inconsistent with logical and epistemological principles. Appropriately designed theoretical and philosophical tests of ideographic discovery operations may be scientifically valid. Empirical tests, however, are incapable of evaluating the scientific merits of competing discovery operations. Nonetheless, empirical comparisons (not tests ) of competing discovery operations may provide insight into the ways discovery operations may be misleading and therefore may play an important role in stimulating critical debate and eventually establishing a scientifically optimal operation. In practice, theoretical and philosophical tests are often combined to test competing discovery operations as rigorously as possible.  相似文献   

8.
Gaze B  Dawson K 《Bioethics》1989,3(4):301-319
The debate over the acceptability of human embryo research takes place within the context of a broader regulatory framework for experimentation with human subjects. Using the Australian situation for illustration, Gaze and Dawson examine the concepts of therapeutic, nontherapeutic, and destructive experimentation in medical practice. They explore the problems of applying these concepts to human embryo research by asking whether the embryo or the woman undergoing in vitro fertilization (IVF) treatment is the experimental subject. They argue that when the embryo is treated as the sole subject, the woman is lost sight of, and that research that is therapeutic for the embryo may be nontherapeutic for her. Regulation of embryo research should take into account the relationship between research and the woman's treatment, the dependence of embryos upon women for gestation, and the empirical, uncertain nature of biomedical knowledge.  相似文献   

9.
We introduce a Bayesian theoretical formulation of the statistical learning problem concerning the genetic structure of populations. The two key concepts in our derivation are exchangeability in its various forms and random allocation models. Implications of our results to empirical investigation of the population structure are discussed.  相似文献   

10.
Competitive coexistence in spatially structured environments: a synthesis   总被引:8,自引:0,他引:8  
Theoretical developments in spatial competitive coexistence are far in advance of empirical investigations. A framework that makes comparative predictions for alternative hypotheses is a crucial element in narrowing this gap. This review attempts to synthesize spatial competition theory into such a framework, with the goal of motivating empirical investigations that adopt the comparative approach. The synthesis presented is based on a major axis, coexistence in spatially homogeneous vs. heterogeneous competitive environments, along which the theory can be organized. The resulting framework integrates such key concepts as niche theory, spatial heterogeneity and spatial scale(s) of coexistence. It yields comparative predictions that can guide empirical investigations.  相似文献   

11.
In the present conceptual review several theoretical and empirical sources of information were integrated, and a hybrid model of the neural representation of complex mental processing in the human brain was proposed. Based on empirical evidence for strategy-related and inter-individually different task-related brain activation networks, and further based on empirical evidence for a remarkable overlap of fronto-parietal activation networks across different complex mental processes, it was concluded by the author that there might be innate and modular organized neuro-developmental starting regions, for example, in intra-parietal, and both medial and middle frontal brain regions, from which the neural organization of different kinds of complex mental processes emerge differently during individually shaped learning histories. Thus, the here proposed model provides a hybrid of both massive modular and holistic concepts of idiosyncratic brain physiological elaboration of complex mental processing. It is further concluded that 3-D information, obtained by respective methodological approaches, are not appropriate to identify the non-linear spatio-temporal dynamics of complex mental process-related brain activity in a sufficient way. How different participating network parts communicate with each other seems to be an indispensable aspect, which has to be considered in particular to improve our understanding of the neural organization of complex cognition.  相似文献   

12.
This paper describes one complete and one ongoing empirical study in which philosophical analyses of the concept of the gene were operationalized and tested against questionnaire data obtained from working biologists to determine whether and when biologists conceive genes in the ways suggested. These studies throw light on how different gene concepts contribute to biological research. Their aim is not to arrive at one or more correct 'definitions' of the gene, but rather to map out the variation in the gene concept and to explore its causes and its effects.  相似文献   

13.
The structural features of carbonic anhydrase (carbonate hydro-lyase; EC 4.2.1.1) in aqueous solution were probed by the positron annihilation technique. The data obtained under varying conditions of temperature, pH, and enzyme concentration were interpreted in terms of the free volume model. The change of enzymic activity with temperature is accompanied by a change in free volume of the protein. Upon thermal denaturation an irreversible change in free volume of the molecule occurred. At low temperatures the protein-water interactions were investigated. These results are discussed in terms of current concepts of structure-function relationships in proteins. This study shows the sensitivity of the positron annihilation method toward the structure of proteins related to their overall conformation and to the nature of bound water.  相似文献   

14.
Researchers across the health sciences are engaged in a vigorous debate over the role that the concepts of "race" and "ethnicity" play in health research and clinical practice. Here we contribute to that debate by examining how the concepts of race, ethnicity, and racism are used in medical–anthropological research. We present a content analysis of Medical Anthropology and Medical Anthropology Quarterly , based on a systematic random sample of empirical research articles ( n = 283) published in these journals from 1977 to 2002. We identify both differences and similarities in the use of race, ethnicity, and racism concepts in medical anthropology and neighboring disciplines, and we offer recommendations for ways that medical anthropologists can contribute to the broader debate over racial and ethnic inequalities in health.  相似文献   

15.
Researchers across the health sciences are engaged in a vigorous debate over the role that the concepts of "race" and "ethnicity" play in health research and clinical practice. Here we contribute to that debate by examining how the concepts of race, ethnicity, and racism are used in medical-anthropological research. We present a content analysis of Medical Anthropology and Medical Anthropology Quarterly, based on a systematic random sample of empirical research articles (n = 283) published in these journals from 1977 to 2002. We identify both differences and similarities in the use of race, ethnicity, and racism concepts in medical anthropology and neighboring disciplines, and we offer recommendations for ways that medical anthropologists can contribute to the broader debate over racial and ethnic inequalities in health.  相似文献   

16.
The importance of evolutionary parallelisms and their differences from evolutionary convergences have been historically underappreciated, as recently noticed in Gould's last book `The structure of evolutionary history'. In that book, Gould make an effort to distinguish and to reinterpret these concepts in the light of the new discoveries of the last decades on developmental biology and genetics, presenting the elegant metaphor of `Pharaonic bricks versus Corinthian columns'. In this paper I will briefly discuss these concepts, and will argue that, despite the advances that have been made to define them in theory, it is rather hard to differentiate them in a practical phylogenetic context. In order to do so, I will provide some few examples from my own empirical studies on the last years of one of the most morphologically and taxonomically diverse groups of Vertebrates, the catfishes.  相似文献   

17.
1. New scientific concepts such as models of chaos, complex dynamics and non-linear interactions have the potential to contribute to an improved understanding of ecological patterns and processes. This paper discusses some of the known dynamics of phytoplankton, pelagic food chains and nutrient cycles in the light of some of these new concepts. The paper brings these new conceptual models together with data from a wide range of sources in an attempt to produce a synthesis of system behaviour which allows us to understand why some things are inherently more predictable than others. In particular it looks at the limnological management tools of empirical biomass models and biomanipulation and at the need for prediction of species composition. 2. The structures observed in ecosystems (nutrient pools, sizes, species, temporal/spatial patterns) show properties at a spectrum of scales, as do the processes (fluxes, grazing, competition). Both respond to a spectrum of external perturbations that may be climatologically or anthropogenically induced. Empirical biomass models work because of the annual averaging of pattern and process and because of some inherent properties of the functioning of pelagic ecosystems. Many aspects of ecosystem pattern and process vary in a regular way with trophic state. Examination of empirical data sets can lead to an improved understanding of system behaviour if questions are asked about why things happen the way they do. 3. Feedbacks between pattern, process and periodicity are seen to be an inherent property of the system. Understanding the fundamental dynamics of non-linear interactions in ecosystems may make it possible to exploit the external spectrum of environmental perturbations and to control system function. For example, by imposing external physical perturbations on pelagic systems it may be possible to manipulate the species composition of the phytoplankton community. Because of the complexity of possible interactions both ‘horizontally’ between species and ‘vertically’ within the food chain, any prediction of species composition will necessarily be probabilistic.  相似文献   

18.
Analytical monitoring surveys routinely confirm that organisms in the environment are exposed to complex multi-component pharmaceutical mixtures. We are hence tasked with the challenge to take this into consideration when investigating the ecotoxicology of pharmaceuticals. This review first provides a brief overview of the fundamental approaches for mixture toxicity assessment, which is then followed by a critical review on the empirical evidence that is currently at hand on the ecotoxicology of pharmaceutical mixtures. It is concluded that, while the classical concepts of concentration addition and independent action (response addition) provide a robust scientific footing, several knowledge gaps remain. This includes, in particular, the need for more and better empirical data on the effects of pharmaceutical mixtures on soil organisms as well as marine flora and fauna, and exploring the quantitative consequences of toxicokinetic, toxicodynamic and ecological interactions. Increased focus should be put on investigating the ecotoxicology of pharmaceutical mixtures in environmentally realistic settings.  相似文献   

19.
The present work is intended to demonstrate that most of the paradoxes, controversies, and contradictions accumulated in molecular and cell biology over many years of research can be readily resolved if the cell and living systems in general are re-interpreted within an alternative paradigm of biological organization that is based on the concepts and empirical laws of nonequilibrium thermodynamics. In addition to resolving paradoxes and controversies, the proposed re-conceptualization of the cell and biological organization reveals hitherto unappreciated connections among many seemingly disparate phenomena and observations, and provides new and powerful insights into the universal principles governing the emergence and organizational dynamics of living systems on each and every scale of biological organizational hierarchy, from proteins and cells to economies and ecologies.  相似文献   

20.
The author tried in a somewhat limited work to quantitatively correlate the electronic and steric intramolecular interactions of substituents on the amino group (influencing the enzymatic reactions of aromatic amines) and the mutagenic event. It was assumed that there is a correlation between these biotransformations and the electronic state of aromatic amines at the ionic dissociation equilibrium. The approach is rather empirical and arbitrary but the overall agreement between experimental mutagenic potencies and the values calculated was encouraging and led the author to further developments. It is hoped that the concepts used in this work may be applied to other aromatic molecules bearing an amino group.  相似文献   

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