共查询到20条相似文献,搜索用时 9 毫秒
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Between 1952 and 1963, the Abbé Glory conducted excavation in the Lascaux Cave. He discovered many artefacts useful for the Prehistoric painter. Today this material is kept in the “Institut de Paléontologie Humaine” in Paris. Some of this material, as well as the painting matter of the “Blazons” of the Black Cow Panel of the Nef, were examined and analysed by electron microscopy: SEM and TEM. Yellow, ocher and red pigments are iron oxides and black pigments are manganese oxides. The results indicate that the pigments were by no means heated, nor associated with any extender. Nevertheless the variety of the raw matter indicates a real strategy to exploit nature in order to match the desired hue and the texture of the painted panel. 相似文献
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Anne Dambricourt Malassé 《Acta biotheoretica》1995,43(1-2):113-125
The recent discovery of a phenomenon of craniofacial growth, called craniofacial contraction, throws a new light on the process of hominization. The main interest of this discovery lies in a growth principle combining the different craniofacial units, that is to say, the neurocranium (neural skull), the chondrocranium (basal skull) and the splanchnocranium (visceral archs including the mandible). Until recent years, these different parts were considered as neighbouring element without any morphogenic or morphodynamic connection. But now, we know that the morphogenesis of the base of the skull governs that of the face. This basicranial morphogenesis is the occipital flexion. It generates morphogenic correlations with the face since embryogenesis. The ontogenic pathway of this phenomenon is the craniofacial contraction. It concerns embryonic dynamics connected with the spatial development of the embryonic neural system, the neural tube. These morphodynamics are common to each primate species, but they are differenciated by the amplitude of the embryonic contraction. We ask ourself the question: is hominization of the neurocephalic embryogenesis, that is the craniofacial contraction, plausible over a very long period, with gradual and chaotic evolutionary pathways, or, on the contrary, is the complexity of such an embryonic phenomenon, a limiting factor generating determined and predictible ontogenic thresholds? The study of extant and fossil primate skulls demonstrates that species are organized around 6 levels of embryonic contraction, which, starting from 60 millions years, evolve from the less to the most contracted skull. Among each ontogenic level, living and fossil species develop from the same embryonic system but between both levels, the embryos suddenly are reorganized. Therefore, I have defined an evolutive ontogenic unity, that is the fundamental ontogenesia. The cephalic pole has a fundamental ontogenesis, meaning that, beyond the diversities, we can see the same contraction in many living and extinct species. The ontogenic diversities are the result of the microevolution and are not predictible. In such a perspective, the ontogenic morphodynamics evolve with chaotic trajectories. But, between two embryonic levels, or two fundamental ontogeneses, evolutionary modalities are different. Eventually, from 60 millions years to XXth century, we observe the same phenomenon than during human ontogenesis; hominization of the cephalic pole is a craniofacial contraction. The evolutive pathway is stable, whatever the number of thresholds, the cranial shape changes but the ontogenic trajectory is preserved. This is a macroevolution because the embryonic system is reorganized. The logics of the phenomenon are an increasing dynamization, the human ontogenesis is the more unstable and the longer morphodynamics to stabilize the craniofacial contraction. To conclude, hominization is an iteration of an ontogenic process when embryos reach successive dynamic thresholds. The attractors are neither static, periodic, nor chaotic because the successive ontogenic trajectories are themselves in a stable evolutive trajectory, and the results with increasing contraction, complexified neocortical tissues and cephalocaudal reorganization are predictible. During hominization, irreversibility and innovations do not emerge with chaotic determinism, but with harmonic determinism in association with the correlations established between the embryonic tissues. When the system is destabilized, the embryonic systems do not forget the previous ontogenic pattern, on the contrary, they develop the pattern with new dynamical conditions. This sort of phenomenon is not described in the sciences of complexity. In the present case, we are in front of many millions years and the necessity to propose new concepts such as a new familly of attractors, namely the harmonic attractors. 相似文献
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Atwood D. Gaines 《Culture, medicine and psychiatry》2012,36(4):578-581
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Tommaso Castelli 《Archives of microbiology》1954,20(4):323-342
Zusammenfassung Es wird eine Übersicht über die von Verf. und anderen seit 1933 isolierten Hefestämme (über 4000 Stämme mit 11 Arten) aus italienischen Weinmosten gegeben. Am häufigsten sind vertretenSaccharomyces ellipsoideus undKloeckera apiculata, jene von Norden nach Süden, diese von Süden nach Norden häufiger werdend. Ähnliche Unterschiede finden sich unter den übrigen, Arten:Sacch. mangini unditalicus z. B. sowiehansenula Guilliermondi fehlen im Norden fast völlig,Kloeckera magna undTorulopsis pulcherrima verhalten sich umgekehrt.Die sporogenen Hefen nehmen, im Gegensatz zu den asporogenen, nach Süden zu. In wärmeren Landschaften finden sich in den höheren Lagen mehr asporogene als, in den tieferen Lagen.Weiter wird die Gärkraft der isolierten Stämme (Vol% Alkohol) in Beziehung zu der Häufigkeit der Stämme in den einzelnen Landschaften gesetzt, woraus sich klimatisch bedingte Abhängigkeiten ergeben, die wiederum in Beziehung zu den jeweils vorherrschenden Arten stehen.Zum Schluß werden Ausblicke auf künftige, Möglichkeiten gegeben (Mischgärungen usw.), wobei die Verwendung vonTorulaspora rosei mit ihrem hohen Alkoholbildungsvermögen und geringer flüchtiger Säure besonders erörtert wird.
Rapport présenté au VI° Congrès International de Microbiologie. Rome 6.–12. Septembre 1953. 相似文献
Rapport présenté au VI° Congrès International de Microbiologie. Rome 6.–12. Septembre 1953. 相似文献
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Alexandre Laforgue 《Acta biotheoretica》1994,42(1):63-75
Introduction
Atoms theory and symmetry theory dominated physics. Symmetry propagation and interactions verify the Curie principle. But its violation by symmetry breaking is spontaneous.Fragility is creative. An information breaks a generalized symmetry. Results on symmetry breakings are not valid for fuzzy symmetries. The breaking of a fuzzy symmetry leads only to a pour symmetry (Fig.1). Homogeneity breaking, and atom of time are not usual concepts. We examine in this work symmetry breakings which generate the living time.Relativistic Time-Space Breaking
- Medium and environment of living define ordinary referential of space and referential of time. Astronomical phenomena following classical mechanics and microphysical phenomena following quantum mechanics can be written with the same t coordinate.
- Relativity corrections. Schrödinger's Quantum mechanics (Eq.0) approximately governs molecular systems (Relativity corrections can be expressed as physical effects in the above defined referential).
- Time reversal symmetry. The well-known Wigner's transformation determines the microscopic reversibility.
- The three essential particle-vacancy equilibria. This transformation is verified by all particle-vacancy reciprocity. Vacancy moves like particle but with negative moment and positive kinetic energies. Only three biochemical equilibria admit this time reversal symmetry, namely: oxydo-reduction, acido-basicity, fluidity-viscosity. In these case, reacting electron, solvated proton, water molecule are respectively antagonist of the corresponding vacancy.
- Fuzzy character of time reversal symmetry. Dirac's equation does not admit this symmetry which only appears at the “non relativistic” limit of quantum phenomena. Hence particle-vacancy reciprocity is fuzzy according to the experimental evidence. (Laforgue et al., 1988).
Oriented Time
- From the universal reversible time, an additional breaking generates the oriented time, both in the astronomical and in the living matter.
- Irreversibility for the environment. We refer to Prigogine and Stengers (1988).
- Irreversibility for the living matter. We refer to Lochak (1986). Because equation (0), above discussed, is “microreversible” the second breaking could come from an additional term vanishing in the stationary states but increasing with time in evolutionary processes.
- Negative times. Taking into account the fuzzy character of the time reversal symmetry, the third breaking cannot suppress completely the occurrence of negative times. Reversed time is controlled by direct time. Except in the three above reported cases, time reversal symmetry is not verified by the medium. Free motion of the particle following eg.(0) or of the vacancy following time reversal reciprocal equation takes place only during short jumps from an interaction site to an other. Fig. 2 schematizes the law of motion of the electric charge corresponding to the transport by proton or by proton vacancy in an unitary field (fluctuations are neglected). The reserved jumps are estimated in the range of 10?12s. It is not excluded that such a jump can control a direct phenomenon.
- The living time. Biological phenomenon appears as an oriented set of events. Nevertheless latency or exaltation phases could be perceived. This modulation could be described by positive and negative times additional to the basic time. (Negative can be interpreted as above.)
Living produces Time
- That were not understandable, if time was only a frame, in which change occurs. Taking change as frame and time as effect, we regard biological activity as integrating reversible and irreversible time. Living synchronizes internal and external time by its own effort as it results (Lestienne, 1990) from Chronobiology.
- Time modulation. Let us consider the dy1...dyi...dyp changes in the variables of the system, dy={dyi} has produced dt. We proof (eq.(1) to (4)) that time is modulated by a Φ(y) speed coefficient depending on the medium. tmodulated=tΦ-1 (y)
- The production of reversible time (e.g.acido-basicity) determines time modulation. As above reported it remains some reversibility effects (jumps of negative time) which modulate time. E.g., if an important amount of reagent is necessary to modify an acid-base equilibrium, Φ(y) is small.
- Time modulation and activation-repression reciprocity. As well-known, long tmodulated means repression, short tmodulated means exaltation. Extrema of ? are symmetrical because particle and vacancy are reciprocal. Nevertheless reciprocity is not perfect. E.g., on fig. 3, the wet receptor determines the cell increasing, the dry receptor the cell senescence of a certain alga (Lück, 1962).
- Irreversible time production. Medium accepts entropy. Hence it acts in the second breaking of time. Living extracts the free energy from the medium, like a dissipative structure. That insures an operative point far from the thermodynamical equilibrium.
Consumption of Time
- The three followings correspond to the more trivial time consumption.
- Rhythmical time. Free energy flux is favourable to the arising of order in space or time. This later gives a structure to the living time.
- Mutual dependence of reversible time and rhythms. Time irreversible structure can be controlled by the above considered particle-vacancy equilibrium. Consequently the living time (modulated and structured) is a chemical time connected to molecular properties and to statistical thermodynamics. Practically, the connection between chronobiology and chemistry is important. The use of drugs could be interpreted as a response to an aggression against biorhythms.
- Lifetime. The dead-birth rhythm can be broken in two ways: evolution or indefinite life. This later is non exceptional for the living matter, e.g. in the vegetals where it is connected with the chlorophyllic assimilation; the time reversal significance of which is evident.
- The plan of the alchemist. Indefinitely life has fascinated individuals. Do the human species becomes better adapted by a longer life?
Conclusions
- Atoms of time could exist.
- Biological time is defined by the breaking of five generalized symmetries, namely: Minkovski's space symmetry, reversibility, homogeneity, rhythmicity, generations reproduction.
- Environment and medium determine non relativistic, oriented, structured time.
- At the microphysical scale, a fuzzy time reversal symmetry takes place, the breaking of which is not complete. Reversible time and dominating irreversible time are integrated in living phenomena.
- Three fundamental particle-vacancy reciprocities admit a part of reversibility. Irreversibility governs the all others phenomena.
- Time is produced chemically.
- A new perspective is the connection between chemical equilibria and rhythms including the time of the life.
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