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1.
The cybernetic definition of a living individual proposed previously (Korzeniewski, 2001) is very abstract and therefore describes the essence of life in a very formal and general way. In the present article this definition is reformulated in order to determine clearly the relation between life in general and a living individual in particular, and it is further explained and defended. Next, the cybernetic definition of a living individual is confronted with the real world. It is demonstrated that numerous restrictions imposed on the cybernetic definition of life by physical reality imply a number of particular properties of life that characterize present life on Earth, namely: (1) a living individual must be a dissipative structure (and therefore a low-entropy thermodynamic system out of the state of equilibrium); (2) spontaneously-originated life must be based on organic compounds; (3) evolutionarily stable self-dependent, free-living individuals must have some minimal level of complexity of structure and function; (4) a living individual must have a record of identity separated from an executive machinery; (5) the identity of living individuals must mutate and may evolve; (6) living individuals may collect and accumulate information in subsequent generations over very long periods of time; (7) the degree of complexity of a living individual reflects the degree of complexity of its environment (ecological niche) and (8) living individuals are capable of supple adaptation to varying environmental conditions. Thus, the cybernetic definition of a living individual, when confronted with the real physical world, generates most of the general properties of the present life on Earth.  相似文献   

2.
The light intensity vs. time curve of the light flash of the living firefly has been measured. Unlike the purified firefly enzyme system in aqueous solution, the living system does not show light decay conforming to a double exponential time curve, to simple first or second order decay, or to solid-state Elovich kinetics. Light decay of the living flash does show linearity in a probit vs. square root of time plot, which may indicate a reaction rate-limited by cooperative interactions of a biological phase transition. The observation that the kinetics of the firefly light system differ in the living cell from those in the purified system suggests that in the living system supramolecular factors control the rate of the reaction.  相似文献   

3.
The intensity of immune response to live measles vaccine varies in children living in different climatic and geographical regions. The least intensive immunogenesis is registered in children living in the Arctic regions. The level of seroconversion in children living in these regions rises in response to measles vaccine containing a 10-fold amount of the virus per immunization dose.  相似文献   

4.
A biosemiotic view of living things is presented that supersedes the mechanistic view of life prevalent in biology today. Living things are active agents with autonomous subjectivity, whose structure is triadic, consisting of the individual organism, its Umwelt and the society. Sociality inheres in every living thing since the very origin of life on the earth. The temporality of living things is guided by the purpose to live, which works as the semantic boundary condition for the processes of embodiment of the subjectivity. Freedom at the molecular and cellular levels allows autonomy and spontaneity to emerge even in single cell organisms, and the presence of the dimension of mind in every living thing is deduced. Living things transcend their individualness, as they live in historically formed higher order structure consisting of the lineage-species and the society. They also transcend materiality, having the dimension of mind.  相似文献   

5.
A study was recently done to investigate the outcomes of written living wills in Japan, which, unlike the United States, does not legally recognize advance directives. This study collected demographic information and predictors of living will use among families and guardians who used the living will form provided by the Japan Society for Dying with Dignity. According to the results of the study, affliction with cancer and death in a hospital was the best predictor of written living will use. Research on physicians' treatment limitation and withdrawal behaviors in the clinical setting is needed to better understand the actual impact of living wills. Such research can provide better understanding of where boundaries of self-determination are drawn and how to respect autonomy in Japan.  相似文献   

6.
This work deals with the current stage of study of energy exchange between living organ-isms and the environment. In the epoch of molecular biology, study of energy exchange might have seemed a study of old, well known concepts. However, the retrospective insight into the energy exchange of quite a few organisms allows obtaining new data about development of energetics of the living world, approaches to interesting comparisons, opens the earlier unknown quantitative relations in energetics of living organisms, provides a possibility of analyzing causes of very high values of energy consumption by living organisms, causes of different sensitivity of living organisms to deficit of energy, etc. Based on all these data, there have been noted 12 principal moments or postulates in development of energetics of the living world from the most ancient to the present time.  相似文献   

7.
Based on fieldwork among the Sa'dan Toraja of Indonesia, this article examines a specific relationship between the living and the dead. It is a relationship which is usually described in terms of intimacy. Within this intimacy, the living and the dead are described as sharing the same desires. Furthermore, as far as the living are concerned, these desires have to be expressed in words and acted out in the form of mortuary sacrifices. In this way, the living are said to remember the dead. My discussion focuses on the implications of this memory.  相似文献   

8.
干旱地区生态-生产-生活承载力变化情势与演变情景分析   总被引:19,自引:0,他引:19  
方创琳  鲍超  张传国 《生态学报》2003,23(9):1915-1923
干旱地区实现可持续发展的重要途径在于协调生态系统、生产系统和生活系统三者之间的关系,提高生态承载力、生产承载力和生活承载力,促进三大系统和谐高效运行。以干旱地区塔里木河下游尉犁地区为例,探讨了生态-生产-生活系统承载力的基本内涵及其相互作用的基本特点,选取生态-生产-生活系统承载力的综合测度指标,采用状态空间的理想点法求解出生态-生产-生活系统承载力的理想状态值和实际指数值,综合评估了生态-生产-生活系统承载力的现状情势,进而采用多模型互补对接支持下的系统动力学模型预测未来30a塔里木河下游尉犁地区生态-生产-生活承载力变化的总体变化情景。结果认为,在不同生活水平下的塔里木河下游生态-生产-生活承载力目前均处于超载状态,干旱脆弱的生态环境严重制约着生态承载力的提高,经济发展水平低下限制着生产系统承载力的提升,人口素质和生活质量低下成为制约生活承载力提高的长期因素,但未来30a生态-生产-生活承载力的整体超载状况将趋于缓解,自2009年起的整体承载力将处于可载状态,居民生活水平有望达到小康标准,到2054年以后在可载状态下居民生活水平有望达到富裕和现代化标准,但尚须做数百年的长期努力。  相似文献   

9.
《Biochemical education》1998,26(4):286-289
The most fundamental of questions in biology, namely that of the origin of living systems, is being lost to teaching and a new technique to rekindle interest in it must be found. This paper presents a novel idea of teaching a scientific concept using a poem, which describes the major perspectives on the origins of living systems, as the medium of instruction. All of the major schools of thought — chemical evolution, DNA vs. RNA, protocell formation, coacervates, panspermia and special creation — are discussed. The aim of the paper is not to be a definitive review on the origin of living systems, but rather to be a focal point on which to hinge further discussion.  相似文献   

10.

Background

The early evolution of living marsupials is poorly understood in part because the early offshoots of this group are known almost exclusively from jaws and teeth. Filling this gap is essential for a better understanding of the phylogenetic relationships among living marsupials, the biogeographic pathways that led to their current distribution as well as the successive evolutionary steps that led to their current diversity, habits and various specializations that distinguish them from placental mammals.

Methodology/Principal Findings

Here we report the first skull of a 55 million year old peradectid marsupial from the early Eocene of North America and exceptionally preserved skeletons of an Oligocene herpetotheriid, both representing critical groups to understand early marsupial evolution. A comprehensive phylogenetic cladistic analysis of Marsupialia including the new findings and close relatives of marsupials show that peradectids are the sister group of living opossums and herpetotheriids are the sister group of all living marsupials.

Conclusions/Significance

The results imply that North America played an important role in early Cenozoic marsupial evolutionary history and may have even been the center of origin of living marsupials and opossums. New data from the herpetotheriid postcranium support the view that the ancestral morphotype of Marsupialia was more terrestrial than opossums are. The resolution of the phylogenetic position of peradectids reveals an older calibration point for molecular estimates of divergence times among living marsupials than those currently used.  相似文献   

11.

Purpose

This paper explores the issue of fairness in global supply chains. Taking the Western European clothing supply chain as a case study, we demonstrate how applying a normative indicator in Social Life Cycle Assessment (SLCA) can contribute academic and practical insights into debates on fairness. To do so, we develop a new indicator that addresses some of the limitations of the living wage for SLCA.

Methods

We extend the standard form of living wage available for developing countries to include income tax and social security contributions. We call this extension ‘living labour compensation’. Using publically available data, we estimate net living wages, gross living wages, and living labour compensation rates for Brazil, Russia, India, and China (BRIC) in 2005. We then integrate living labour compensation rates into an input-output framework, which we use to compare living labour compensation and actual labour compensation in the BRIC countries in the Western European clothing supply chain in 2005.

Results and discussion

We find that in 2005, actual labour compensation in the Western European clothing supply chain was around half of the living labour compensation level, with the greatest difference being in the Agricultural sector. Therefore, we argue that BRIC pay in the Western European clothing supply chain was unfair. Furthermore, our living labour compensation estimates for BRIC in 2005 are ~ 35% higher than standard living wage estimates. Indeed, adding income taxes and employee social security contributions alone increases the living wage by ~ 10%. Consequently, we argue there is a risk that investigations based on living wages are not using a representative measure of fairness from the employee’s perspective and are substantially underestimating the cost of living wages from an employer’s perspective. Finally, we discuss implications for retailers and living wage advocacy groups.

Conclusions

Living labour compensation extends the living wage, maintaining its strengths and addressing key weaknesses. It can be estimated for multiple countries from publically available data and can be applied in an input-output framework. Therefore, it is able to provide a normative assessment of fairness in complex global supply chains. Applying it to the Western European clothing supply chain, we were able to show that pay for workers in Brazil, Russia, India, and China is unfair, and draw substantive conclusions for practice.
  相似文献   

12.
A Serani-Merlo 《Biological research》2001,34(3-4):179-89; discussion 191-4
Theories on the nature of living beings have been present in our culture since the beginnings of science and philosophy in ancient Greece. The two major theoretical approaches to living beings, philosophical mechanism and Aristotelian realism, appear today with renewed force in almost every confrontation concerning the theoretical considerations of life. In recent times a strong and prolific school of thought has risen, headed by the Chilean neurobiologist Humberto Maturana. This author and his school have developed a complex and articulated theoretical system beginning with a theory of living beings and a 'biology of cognition,' and extending to ethical, political, and even metaphysical considerations. This work is one of the first efforts to perform a scholarly analysis of Maturana's doctrines on living beings, starting with the analysis of "On machines and living beings". The book's introduction is placed under scrutiny in this paper. A strongly mechanist philosophical manifesto is dogmatically stated at the beginning of a supposedly purely scientific approach. The challenges for a rational foundation of philosophical mechanism are critically highlighted and briefly discussed.  相似文献   

13.
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   

14.
A polarographic method for the measurement of the available oxygen in the muscle of living carp by the use of a platinum microelectrode is proposed. The oxygen and the reference electrodes were assembled in a single insertion piece which was implanted in the muscle of a living carp maintained in a special experimental chamber. Curves for normal oxygen levels corresponding to air-saturated water, as well as to a carbogene-saturated water, were obtained. The method can be considered adequate for the measurement of tissue oxygen in living fishes.  相似文献   

15.
The woodmouse is primarily a woodland species but it also occurs on maritime sand-dunes. The home ranges of mice living on the sand-dunes are much larger than those of animals living in woodlands. Here we test the hypothesis that this difference is due to the fact that woodland provides substantially more food than do sand-dunes. Our experimental approach was to provide supplementary food in the form of wheatgrain to a sand-dune population and to compare range sizes with a control population. Range sizes on the supplemented area were significantly smaller than the controls and essentially similar to those of woodmice living in deciduous woodland.  相似文献   

16.
Biological electrosprays are rapidly becoming a robust means by which to engineer living organisms for applications ranging from tissue repair to developmental biology. We previously reported the ability to electrospray living organisms without compromising their viability, but found it challenging to achieve stability in the jetting of these organisms as a result of the chemical properties of the living cellular suspensions. Jet stability is required for the generation of a near-mono distribution of droplets, which is necessary for the development of electrospray technology as a "drop and place" biotechnique. Recently, we determined the conditions needed to achieve jet stability and were able to generate droplets with a near-mono distribution (<50 microm). In this communication, we elucidate the relationship between jet behaviour and droplet size under stable jetting conditions, with a view to further reducing the droplet size to deposit a single living cell within a droplet. We believe that this level of resolution will make electrospray jetting superior amongst the jet-based biotechnologies presently being developed for the engineering of biological architectures comprised of living cells.  相似文献   

17.
A Ponto-Caspian amphipod Dikerogammarus haemobaphes has recently invaded European waters. In the recipient area, it encountered Dreissena polymorpha , a habitat-forming bivalve, co-occurring with the gammarids in their native range. We assumed that interspecific interactions between these two species, which could develop during their long-term co-evolution, may affect the gammarid behaviour in novel areas. We examined the gammarid ability to select a habitat containing living mussels and searched for cues used in that selection. We hypothesized that they may respond to such traits of a living mussel as byssal threads, activity (e.g. valve movements, filtration) and/or shell surface properties. We conducted the pairwise habitat-choice experiments in which we offered various objects to single gammarids in the following combinations: (1) living mussels versus empty shells (the general effect of living Dreissena ); (2) living mussels versus shells with added byssal threads and shells with byssus versus shells without it (the effect of byssus); (3) living mussels versus shells, both coated with nail varnish to neutralize the shell surface (the effect of mussel activity); (4) varnished versus clean living mussels (the effect of shell surface); (5) varnished versus clean stones (the effect of varnish). We checked the gammarid positions in the experimental tanks after 24 h. The gammarids preferred clean living mussels over clean shells, regardless of the presence of byssal threads under the latter. They responded to the shell surface, exhibiting preferences for clean mussels over varnished individuals. They were neither affected by the presence of byssus nor by mussel activity. The ability to detect and actively select zebra mussel habitats may be beneficial for D. haemobaphes and help it establish stable populations in newly invaded areas.  相似文献   

18.
The state of microcirculation system and its regulation in peace and after growing physical activity is analyzed on people living in different ecological regions. There are three main types of microcirculation. The level of regulation mechanisms activity depends on the type of microcirculation, region of residence and the value of physical activity. People living in a relatively clean regions have stable mechanisms of regulation despite of the level of activity. Mesoemic type living in toxic radiation regions have reduced contribution of VLF and LF-fluctuation (p < 0.05); hypoemic type living in toxic regions have VLF and LF-fluctuation (p < 0.05); hyperemic type living in toxic regions have LF-fluctuation (p < 0.05). We can conclude the tension of regulatory machanisms in microcirculation system increases under ecological pressure and borders on failure of adaptation process.  相似文献   

19.
A field experiment was conducted to investigate the effects of white clover living mulch on the arbuscular mycorrhizal (AM) fungus colonization of corn roots and the yield of silage corn. The following seven treatments were setup in a field that had been kept bare by rotary tillage from August 2003 to July 2004: two white clover living mulch treatments without phosphorus (P) application, with the white clover shoots clipped and removed or allowed to lie in place before sowing corn; one no-tillage treatment without P application; and four rotary tillage treatments with different P application rates. White clover was broadcasted in the living mulch treatments in August 2004. In June 2005, the white clover shoots in the living mulch treatments were clipped. After tilling the four rotary tillage treatments, corn was sown in all the treatments. The fallow period before sowing corn was 0 month (living mulch treatments) and 22 months (no-tillage and rotary tillage treatments). At knee high stage, the AM fungus colonization of the corn roots and the P concentrations of the corn shoots in both the living mulch treatments were increased relative to those in the other treatments. The yield of corn tended to increase in the no-tillage and rotary tillage treatments with an increase in the P application rate. On the other hand, the yields of corn in the living mulch treatments without the P application were not significantly different from the maximum yield among the no-tillage and rotary tillage treatments. These results suggested that the white clover living mulch increased the yield of corn by facilitating the AM fungus colonization and improving the P nutrition of corn.  相似文献   

20.
Pedal phalanges of living anthropoids and several Miocene fossil hominoid taxa were studied to reveal functional adaptations of living anthropoid feet and to infer positional behavior of fossil hominoids. Among the examined living anthropoids, Pan has a very developed (long and robust) hallux. Proconsul and Nacholapithecus, a large hominoid from Nachola, northern Kenya, display a moderately long hallux like Alouatta and Cebus, suggesting the well-developed capability of a hallux-assisted power grip. Allometric analyses revealed that the Miocene hominoids examined (mainly from East Africa) as a whole displayed a different scaling pattern about the width of the proximal articular surface of the hallucial terminal phalanx from that of living anthropoids. Larger-sized hominoids display a wider articular surface than comparable-sized living anthropoids while smaller-sized fossil hominoids do the reverse. Such a difference was less marked for the height of the articular surface. These results may suggest that positional adaptations of Miocene hominoids are not merely resultants of a common body size function that is observed in living anthropods. The wide articular surface of fossil hominoid hallucial terminal phalanges suggests an adaptation for vertical climbing and clinging, in which the hallux is kept perpendicularly to the long axis of the vertical support.  相似文献   

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