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1.
In the present, post-genomic times, systemic or holistic approaches to living phenomena are compulsory to overcome the limits of traditional strategies, such as the methodological reductionism of molecular biology. In this paper, we propose that theoretical and philosophical efforts to define life also contribute to those integrative approaches, providing a global theoretical framework that may help to deal with or interpret the huge amount of data being collected by current high-throughput technologies, in this so-called ‘omics’ revolution. We claim that two fundamental notions can capture the core of the living, (basic) autonomy and open-ended evolution, and that only the complementary combination of these two theoretical constructs offers an adequate solution to the problem of defining the nature of life in specific enough—but also encompassing enough—terms. This tentative solution should also illuminate, in its most elementary version, the leading steps towards living beings on Earth.  相似文献   

2.
There is a long history of controversy in ecology over the role of competition in determining patterns of distribution and abundance, and over the significance of the mathematical modeling of competitive interactions. This paper examines the controversy. Three kinds of considerations have been involved at one time or another during the history of this debate. There has been dispute about the kinds of regularities ecologists can expect to find, about the significance of evolutionary considerations for ecological inquiry, and about the empirical credentials of theoretical studies of competition. Each of these elements is examined with an eye toward gaining philosophical clarification of the issues involved. In the process, certain shortcomings of contemporary philosophical theories are revealed. In particular, I argue that plausibility arguments based on background considerations are an important part of the model building tradition, but that current accounts of the structure and evaluation of scientific theories do little to illuminate this side of theoretical ecology.  相似文献   

3.
This review considers the Russian scientific literature on the influence of weak static and of low-frequency alternating magnetic fields on biological systems. The review covers the most interesting works and the main lines of investigation during the period 1900 to the present. Shown here are the historical roots, beginning with the ideas of V. Vernadsky and A. Chizhevsky, which led in the field of Russian biology to an increasing interest in magnetic fields, based on an intimate connection between solar activity and life on the Earth, and which determined the peculiar development of Russian magnetobiology. The variety of studies on the effects of magnetic storms and extremely low-frequency, periodic variations of the geomagnetic field on human beings and animals as well as on social phenomena are described. The diverse experiments involving artificial laboratory magnetic fields acting on different biological entities under different conditions are also considered. A series of theoretical advances are reviewed that have paved the way for a step-by-step understanding of the mechanisms of magnetic field effects on biological systems. The predominantly unfavorable influence of magnetic fields on living beings is shown, but the cases of favorable influence of magnetic fields on human beings and lower animals are demonstrated as well. The majority of Russian investigations in this area of science has been unknown among the non-Russian speaking audience for many reasons, primarily because of a language barrier. Therefore, it is hoped that this review may be of interest to the international scientific community.  相似文献   

4.
The Senoi Semai of Malaysia have frequently been cited as examples in the debates over the wellsprings of human violence. Numerous writers have employed selected Semai ethnographic material to support assertions that, their apparent peacefulness notwithstanding, Semai are in reality bloodthirsty killers. This assertion has in turn been used as evidence in support of a variety of approaches whose common thread is a view of aggressiveness and violence as somehow innate in human beings. The authors of this article, whose publications form the basis of most anthropological knowledge of Semai life and culture, draw on their own published and unpublished work as well as on documentation from other sources to refute these interpretations. We hold that Semai life is, as first-hand observers have described it, notably free of interpersonal violence, and we argue that misrepresentations rooted in particular theoretical or philosophical a priori assumptions are scientifically untenable and culturally slanderous.  相似文献   

5.
Shibata T  Ueda M 《Bio Systems》2008,93(1-2):126-132
Theoretical considerations of stochastic signal transduction in living cells have revealed the gain-fluctuation relation, which provides a theoretical framework to describe quantitatively how noise is generated, amplified and propagated along a signaling cascade in living cells. We chose the chemotactic signaling of bacteria and eukaryotic cells as a typical example of noisy signal transduction and applied the gain-fluctuation relation to these signaling systems in order to analyze the effects of noise on signal transduction. Comparing our theoretical analysis with the experimental results of chemotaxis in bacteria Escherichia coli and eukaryote Dictyostelium discoideum revealed that noise in signal transduction systems limits the cells' chemotactic ability and contributes to their behavioral variability. Based on the kinetic properties of signaling molecules in living cells, the gain-fluctuation relation can quantitatively explain stochastic cellular behaviors.  相似文献   

6.
The relation between modern multivariate statistical analysis and common objectives in biological anthropology is discussed. Many formal statistical assumptions should be satisfied to fully justify multi-variate analysis, but rarely are. Their failure does not have as adverse an effect upon scientific research as some procedural errors in research design. These include the treatment of single specimens as if they are samples, and the failure to separate considerations of size and shape. The superiority of elaborate multivariate distances over simpler quantitative techniques, inferred from the former's consideration of trait intercorrelations, is unwarranted from both theoretical and practical aspects. Based on these points and several comparative examples of analyses, it is argued that simpler, non-statistical approaches such as those of the school of numerical taxonomy have much to offer primato-logical studies. Classic multivariate statistics, while useful for studying closely similar living populations, are considerably more limited in usefulness and significance for paleoanthropological studies.  相似文献   

7.
The progress in artificial intelligence enables us to conceive adaptive systems whose characteristics are nearer and nearer to those of living beings. These characteristics though depend on ingenious choices by the designer of these systems: Initial conditions, parameters, optimisation functions, gradient and measure of fitness within the environment. Nevertheless, in living systems which are non-finalist, there are no programmers or designers to conceive of such ingenious choices. Our paper "Self-Programming Machines (I)" presents a non-finalist model since initial states and functions are randomly chosen at the beginning and once and for all. In spite of the fact that they are non-finalist, these machines always stabilise at fixed points when they are connected to an external process. This paper studies the dynamics of a mono-layered network of self-programming machines driving a real device. "the Ashby homeostat", and shows the striking properties of such networks. This system stabilises only at fixed points even if it is subjected to small perturbations or intentional breakdowns such as a reversal of power supply or disconnection of one or several motors. Real and simulated experiences are compared and theoretical results are demonstrated.  相似文献   

8.
Living systems are capable to have appropriate responses to unpredictable environment. This kind of self-organization seems to operate as a self-programming machine, i.e. an organization able to modify itself. Until now the models of self-organization of living beings proposed are functions solutions of differential systems or transition functions of automata. These functions are fixed and these models are therefore unable to modify their organization. On the other hand, computer science propose a lot of models having the properties of adaptive systems of living beings, but all these models depend on the comparison between a goal and the results and ingenious choices of parameters by programmers, whereas there are no programmer's intention nor choice in the living systems. From two best known examples of adaptive systems of living beings, nervous system and immune system that have in common that the external signals modify the rewriting of their organization and therefore work as self-organizing machines, we devised machines with a finite set of inputs, based upon a recurrence, are able to rewrite their organization (Self-programming machines or m(sp)) whenever external conditions vary and have striking properties of adaptation. M(sp) have similar properties whatever the operation defining the recurrence maybe. These results bring us to make the following statement: adaptive properties of living systems can be explained by their ability to rewrite their organization whenever external conditions vary under the only assumption that the rewriting mechanism be a deterministic constant recurrence in a finite state set.  相似文献   

9.
This article presents research concerning the way in which primary school pupils in southern Spain interpret the concepts of population and species. The results show that, for the concept of population, there was an intense anthropocentrism in pupils’ responses, while for the concept of species, only animals were considered as living creatures. These interpretations influence the vision that the students will develop of ecosystems and biodiversity, as well as their respect and care for living beings. We propose some suggestions in order to improve the teaching of these concepts in primary education.  相似文献   

10.
This article questions whether philosophical considerations play any substantial role in the actual process of scientific research. Using examples mostly from the nineteenth century, it suggests that scientists generally choose their basic theoretical orientation, and their research strategies, on the basis of non-rationalized feelings which might be described as instinct or intuition. In one case where methodological principles were the driving force (Charles Lyell's uniformitarian geology), the effect was counterproductive.  相似文献   

11.
Despite a certain interest in the discipline, Alexander von Humboldt did not personally contribute much to the progress of palaeozoology. His most remarkable input derived from a communication about hand-like archosaur footprints from the Buntsandstein at the very acme of the important controversy that the discovery of these fossils generated (1835). Humboldt thought that the tracks were probably from a possum-like marsupial, but he did not discount that they could be from a primate. This study is characterized by its superficiality: both the anatomical comparisons and the considerations of the functional morphology of locomotion are very poor. Its effect on the scientific community proved about nil, in both the short and the long run, and Humboldt may himself have doubted his initial conclusions in later years. Nevertheless, in contrast with some contemporaneous renowned geognosts, he had no hesitation from the beginning that the footprints were genuine. He also did not hesitate to weaken the belief of the time on the timing of the succession of organised beings in geological ages, naturally without lapsing into “antiprogressionism”.  相似文献   

12.
A comparative study of the tuberculin potency and reactivity to TAP and PPD-S was made in humans and guinea pigs. A comparison of reactions elicited by TAP and PPD-S was made in two groups of guinea pigs previously inoculated with killed bacilli or with living bacilli. The tuberculin reactions produced by TAP and PPD-S in human beings was studied in school children from rural districts. These children were divided randomly into three groups and each group was given a different amount of TAP and PPD-S. The results obtained are as follows: (1) While relative potency of TAP was relatively much weaker than PPD-S in guinea pigs sensitized with tubercle bacilli, in human beings the tuberculin potency of TAP was approximately 1/2 or 1/3 that of PPD-S. (2) There was a marked difference in the tuberculin reactivity to TAP and PPD-S between guinea pigs immunized with killed bacilli and guinea pigs immunized with living bacilli.  相似文献   

13.
The evolution of the human mind is discussed based on: (i) the fact that living beings interchange matter, energy and information with their environment, (ii) an ontological interpretation of the "reality" of the quantum world, of which logic-mathematics structures are considered constitutive parts, (iii) recent theories according to which living beings are considered as dynamic complex systems organized by information, and (iv) the fact that the evolution of living beings is guided by information about the environment and by intrinsic information on living systems (auto-organization). Assuming the evolution of vision as a model we observe that the driving forces that directed the evolution of the eyes, as dynamic complex systems, are the information about the environment supplied by sunlight and the intrinsic information-gaining mechanism of living organisms. Thus, there exists a convergence toward a visual system with the greatest ability to obtain light information, like the human eye, and also a divergence that leads to the development of specific qualities in some species. As in the case of vision the evolution of the human mind-brain cannot be a consequence of factors unrelated to the object of its own functioning. The human mind was structured for the acquisition from reality of the logic-mathematics structures that underlie the whole universe and consequently of an internal representation of the external world and of its own self. Thus, these structures are, together with the intrinsic capacity for auto-organization of the human brain, the predominant driving force of the human mind evolution. Both factors are complementary.  相似文献   

14.
It was found that pseudocyclical similarities are common in modular organisms due to the peculiarities of their morphogenesis and ontogenesis and the system specifics of the modular organization. An analysis of the structural evolution in the different groups of modular living beings according to the concept of pseudocycles is topical, as it will contribute to the further development of evolutionary morphology and theoretical biology.  相似文献   

15.
The essay review summarizes the intention as well as some of the major topics from the book of A. Moreno and M. Mossio and discusses them against the background of recent considerations on the general understanding of organisms. The authors see themselves in the organicist tradition in biology and propose that a new understanding of living beings can be developed around the notion of organismic autonomy, which enables biological systems to maintain themselves in an environment through directed behavior.  相似文献   

16.
Ia M Varshavski? 《Biofizika》1988,33(2):351-355
Causes conditioning fractionation of carbon isotopes in biological systems are considered. Concepts of E. M. Galimov are discussed. According to these concepts distribution of carbon isotopes between biomolecules and their fragments is quaziequilibrium, i. e. it differs from the equilibrium one by a constant multiplier, which is the same for all the biomolecules of an organism but different for various organisms. These concepts have no theoretical grounds and do not agree with the experimental evidence available. An analysis of experimental data, as well as theoretical considerations, indicate that the observed differences in isotope composition of metabolytes and their fragments in the living organisms are conditioned by the kinetic isotope effects of carbon at the stages of their enzymic transformations and by the portion of substances participating in the reaction. It means that these differences do not depend directly on the constants characterizing the equilibrium distribution of carbon isotopes between corresponding compounds and between different groups inside their molecules.  相似文献   

17.
There is an immense philosophical literature dealing with the notions of normativity and agency, as well as a sizeable and rapidly growing scientific literature on the topic of autonomous agents. However, there has been very little cross-fertilization between these two literatures. As a result, the philosophical literature tends to assume a somewhat outdated mechanistic image of living things, resulting in a quasi-dualistic picture in which only human beings, or the higher animals, can be normative agents properly speaking. From this perspective, the project of 'naturalizing normativity' becomes almost a contradiction in terms. At the same time, the scientific literature tends to misuse 'normativity,' 'agency,' and related terms, assuming that it is meaningful to ascribe these concepts to 'autonomous agents' conceived of as physical systems whose behavior is to be explained in terms of ordinary physical law. From this perspective, the true depth of the difficulty involved in understanding what makes living systems distinctive qua physical systems becomes occluded. In this essay, I begin the attempt to remedy this situation. After some preliminary discussion of terminology and situating of my project within the contemporary philosophical landscape, I make a distinction between two different aspects of the project of naturalizing normativity: (1) the 'Scope Problem,' which consists in saying how widely in nature our concept of normative agency may properly be applied; and (2) the 'Ground Problem,' which consists in rationalizing the phenomenon of normative agency in terms of the rest of our knowledge of nature. Then, in the remainder of this paper, I argue that the Scope Problem ought to be resolved in favor of attributing normative agency, in the proper sense of those words, to living things as such. The Ground Problem will be discussed in a companion paper at a later time.  相似文献   

18.
杆状病毒杀虫剂安全性评价的历史和现状   总被引:6,自引:0,他引:6  
从70年代以来学者们用各种杆状病毒做了大量的针对各类生物甚至人类的安全性试验,几乎所有试验都证明杆状病毒是安全的,但也有个别试验得到不同结论,在这些试验的论文发表后曾引起学术界两次大的争论,这些不同结果后来均被其他学者甚至作者本人用实验否定。90年代以来杆状病毒大量作为载体表达外源基因,其中有些论文报道了在哺乳动物细胞中的表达,引起对杆状病毒安全性的怀疑,本文对此进行了分析总结。本文还利用自己研制的重组杆状病毒杀虫剂的安全性试验对鲜有报道的重组杆状病毒杀虫剂安全性进行了论述。作者认为杆状病毒杀虫剂包括重组杆状病毒杀虫剂都是安全、值得推广应用的。  相似文献   

19.
Bionics, Biological Systems and the Principle of Optimal Design   总被引:1,自引:0,他引:1  
The living world is an exciting and inexhaustible source of high performance solutions to the multitude of biological problems, which were attained as a result of a natural selection, during the millions and millions years evolution of life on Earth. This work presents and comments some examples of high performances of living beings, in the light of the universal principle governing the realm of living matter: Optimal Design Principle. At the same time, the transfer of these optimal solutions, from living matter to the technologies, is also discussed. This transfer is offering new and fertile perspectives to future technologies, which must be more efficient, cheaper and in perfect harmony with the biosphere.  相似文献   

20.
《IRBM》2008,29(2-3):208-220
Living beings are inventing, testing, improving new concepts, solutions and devices from hundred millions years. These living systems are able of self-feeding, they take their energy for the environment and also, they are able of reproduction, adaptation and self-repairing. Living beings as birds, butterflies, sharks and dolphins have optimized flight and swimming and their surface for moving with the lowest energy cost. The golf ball, the wings of aircraft, ships and submarines… are now inspired by the Nature's aero- and hydrodynamism. Our organs and tissues are under the control of millions of microsensors, which measure physical, chemical, mechanical… parameters and are associated to microactuators. This distributed intelligence is present even in the structure of living beings. The wing of fly or dragon fly and also bones have extraordinary characteristics of mechanical resistance and lightness and their complex structure is designed so that at any place there is exactly and appropriate quantities of matter with the good orientation and the smallest weight. The new materials, micro- and nanotechnologies, signal processing, the progress in chemistry and optics… allow us to understand and also to design and build at the scale and size of Nature, using its concepts and taking advantage of the human technologies. It is not always possible to copy directly living beings and their solutions; nature does not give us blue print “ready to copy”. We have to analyze the content of the “huge data bank” of living beings for the adaptation of our technologies. Miniaturization, intelligence, low energy, recycling, low cost, high reliability are the main qualities of “bioinspired devices”. They fit exactly with the needs of modern users. The multidisciplinary and the bioinspired approach have to link engineers, scientists and industrials for taking real benefits.  相似文献   

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