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1.
  1. Growth of the floating aquatic weed, Salvinia, in sterile culture was exponential for at least 2 weeks under standardized conditions.
  2. Increase in light intensity or in CO2 resulted in increases in growth rate, but did not extend the exponential period of growth.
  3. This aquatic plant, like many others, discriminates against calcium relative to strontium.
  4. In culture Salvinia exhibited luxury consumption of N and P.
  5. Because of high C/N ratios, Salvinia may not be a favorable source of animal food, but might be useful in nutrient removal schemes.
  6. In sterile culture, S. molesta produced fewer leaves than S. minima, but maintained a significant increase in leaf area and dry weight. This may be correlated with the ability of the first species to rapidly spread over tropical waterways.
  相似文献   

2.
  1. With fumarate as the terminal electron acceptor and either H2 or formate as donor, Vibrio succinogenes could grow anaerobically in a mineral medium using fumarate as the sole carbon source. Both the growth rate and the cell yield were increased when glutamate was also present in the medium.
  2. Glutamate was incorporated only into the amino acids of the glutamate family (glutamate, glutamine, proline and arginine) of the protein. The residual cell constituents were synthesized from fumarate.
  3. Pyruvate and phosphoenolpyruvate, as the central intermediates of most of the cell constituents, were formed through the action of malic enzyme and phosphoenolpyruvate synthetase. Fructose-1,6-bisphosphate aldolase was present in the bacterium suggesting that this enzyme is involved in carbohydrate synthesis.
  4. In the absence of added glutamate the amino acids of the glutamate family were synthesized from fumarate via citrate. The enzymes involved in glutamate synthesis were present.
  5. During growth in the presence of glutamate, net reducing equivalents were needed for cell synthesis. Glutamate and not H2 or formate was used as the source of these reducing equivalents. For this purpose part of the glutamate was oxidized to yield succinate and CO2.
  6. The α-ketoglutarate dehydrogenase involved in this reaction was found to use ferredoxin as the electron acceptor. The ferredoxin of the bacterium was reoxidized by means of a NADP-ferredoxin oxidoreductase. Enzymes catalyzing the reduction of NAD, NADP or ferredoxin by H2 or formate were not detected in the bacterium.
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3.
  1. Washed cell suspensions of Bdellovibrio bacteriovorus harvested shortly after lysis of their substrate organisms and shaken in buffer have a constant and high endogenous respiration rate for a bout 6 h which then declines sharply to a rate approximately 10% of the original. Viability of cell suspensions shows little change over the first 4–6 h and then decreases by some 50% in 10 h.
  2. Over the first 5–6 h of starvation there is a loss of about 50% of total cell carbon. This loss is distributed about equally between CO2 and small molecules released into the suspending buffer. The protein and nucleic acid contents of the cells decrease concomitantly from time zero during starvation while DNA content remains constant. Ribosomal profiles show a rapid degradation of ribosomes.
  3. In the presence of glutamate or glutamate plus a balanced amino acid mixture, loss of cell material and loss of viability is partially or completely prevented. There is extensive protein turnover when glutamate and an amino acid mixture are available to the bdellovibrio.
  4. The pattern of changes observed in B. bacteriovorus during starvation is compared to reported changes in other species of bacteria, and the significances of its high endogenous respiration and sensitivity to starvation are discussed.
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4.
  1. The present paper deals with the chemolithotrophic growth of a Gram-positive hydrogen bacterium strain 11/x which shows the characteristic features of some coryneform bacteria.
  2. Like other hydrogen bacteria, the strain 11/x is a facultative chemolithotroph and grows on many organic substrates faster than in a mineral medium under an atmosphere of knallgas+CO2. Fully induced, autotrophically grown cells, subcultured mixotrophically on fructose show additive growth.
  3. Cell-free extracts of autotrophically grown cells are able to reduce methylene blue, dichlorophenolindophenol, phenazine methosulphate, menadione, and FMN with hydrogen. Conditions for direct NAD(P) reduction could not be found.
  4. Hydrogenase is formed under autotrophic as well as mixotrophic conditions. In the latter case the rate of hydrogenase formation is diminished depending on the organic substrate. Heterotrophically grown cells do not have any detectable hydrogenase activity. For the induction of hydrogenase in those cells a nitrogen source is a prerequisite.
  5. The formation of ribulose-1,5-diphosphate carboxylase and phosphoribulokinase seems to be regulated in a way similar to that of hydrogenase: the enzymes could only be detected in autotrophically and mixotrophically grown cells but not in those grown heterotrophically.
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5.
  1. The seasonal variation in the water, protein, fat and glycogen contents of the mussel, Mytilus viridis has been studied for the year March, 1974 to March, 1975.
  2. The water level increased during the monsoon season and decreased in summer.
  3. The level of protein, fat and glycogen showed correlation with the reproductive cycle of the mussel.
  4. The protein level was high when the mussels were mature and dropped during the breeding period.
  5. During sex change from male to female in May the protein level remained high whereas during sex change from female to male in October and November it was low.
  6. The fat level was high in mature mussels and declined on spawning.
  7. The glycogen level was at its peak in immature mussels and low in mature.
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6.
  1. The lipid composition of a mutant ofSaccharomyces cerevisiae which cannot synthesize unsaturated fatty acid (UFA) can be extensively manipulated by growing the organism in the presence of added fatty acids.
  2. Growth of the mutant is supported by a wide range of unsaturated fatty acids including oleic, palmitoleic, petroselenic, 11-eicosaenoic, ricinoleic, arachidonic, clupanodonic, linoleic and linolenic acids; 9- and 10-hydroxystearic acids support growth less effectively, but erucic, nervonic, elaidic and saturated fatty acids (C8∶0?C20∶0)* are ineffective. All the fatty acids which support growth are incorporated into cell lipids, apparently without further metabolism.
  3. The effects of altered lipid composition on the energy metabolism of yeast cells were investigated. Cells containing less than approximately 20% of their fatty acids as UFA cannot grow on non-fermentable substrates, and their growth on glucose is restricted to that which can be supported by fermentation alone.
  4. UFA-depleted cells contain mitochondria which are apparently normal in morphology, furthermore they have normal levels of cytochromesa+a 3,b,c 1 andc and respire at normal rates. This suggests that the lesion in energy metabolism produced by UFA-depletion may be the loss of the ability of the mitochondria to couple respiration to phosphorylation.
  5. UFA-depleted cells incorporate added UFA into their cell lipids and subsequently regain the ability to grow on non-fermentable substrates, showing that the lesion in energy metabolism is fully reversible.
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7.
  1. Growth requirements of blue-green algae containing only the c-phycocyanin + chlorophyll a pigment system have been studied under blue light (380–540 nm) which approximates light conditions existing in subsurface waters in nature.
  2. While a few species were capable of very slow photosynthetic growth on minimal medium with NO3 - as nitrogen source, most species were dependent on organic compounds for comparable growth under this condition. Some organisms did quite well with only Casamino Acids as a supplement, others did well with only glucose. One species, Agmenellum quadruplicatum strain PR-6, grew only when glucose and Casamino Acids were supplied simultaneously.
  3. Inhibitory effects of blue light on CO2 fixation and nitrogen metabolism are noted as possible explanations of these responses.
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8.
  1. The total protein, fat and glycogen contents were estimated from the edible clam, P. laterisulca. Seasonal variations in these constituents along with the water content were studied.
  2. The gonad index in P. laterisulca was found to increase during the ripe condition and in winter (December–January) and decrease on spawning.
  3. A relatively high water content was obtained during monsoon (June to September). This might be due to the loss of salts and gain of water in low salinities.
  4. Protein content varied with the reproductive cycle of the clam. The level reached its peak in the mature stage and declined on spawning. Immature clams showed less protein content than gravid ones.
  5. Lipid content started to increase as the gametogenesis commenced, reached its peak in fully mature condition (August) and sharply declined due to the shedding of gametes during spawning.
  6. Glycogen content was high during the period of active gameto-genesis (May–June). A sharp decrease took place when the clams were fully ripe (July). The glycogen might have been utilized in the formation of active ripe gametes.
  7. After starvation for twelve days, total protein and fat contents remained constant, while glycogen content decreased by 66.82%. The water content increased by 4.67%.
  8. Seasonal variation in the organic constituents are discussed in relation to the reproductive cycle of the clam.
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9.
The site of anaerobic respiration in the latex is the serum. The main respiratory substrate is fructose. The CO2 formation in serum is increased by additional fructose on the average about 2.5–3 times. Glucose does not influence CO2 evolution by serum but slightly increases O2 consumption. With respect to sugars, latex serum contains essentially only sucrose and a low amount of raffinose. During the incubation of serum sucrose is hydrolysed, the fructose component is immediately utilized in respiration and glucose accumulates. The rate of CO2 formation in latex as influenced by fructose is negatively related to the rubber content of the latex. Latex with a high rubber content reacts only slightly or not at all on additional fructose. The main limiting factors of latex respiration and sugar utilization are the following:
  1. The deficiency of substrate, due to low activity of β-fructofuranosidase.
  2. The rate of glucose phosphorylation (D'Auzac, Jacob 1967).
  3. Presumably the low activity of phosphoglucoisomerase.
  4. The rubber content of the latex.
  5. The concentration of CO2 in latex; this factor may be important in vivo, in the laticiferous system.
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10.
  1. Polyhedral particles were isolated from cells of Nitrobacter winogradskyi and of Nitrobacter strains K1, K4 and α1. Their physical and biological properties are characterized.
  2. The investigated strains contain polyhedral particles, 1000–1200 Å in size. With increasing age of the culture more particles are found in cells of Nitrobacter. Simultaneously the number of colony producing nitritoxidants decreases.
  3. In strain α1 the loss of the capability to form colonies is connected with partial lysis of the cell and release of particles.
  4. A homogeneous fraction of particles was obtained by zone density gradient centrifugation in Tris-Mg-SH-buffer.
  5. The polyhedral particles have a sedimentation coefficient of s w,20 0 =825S and a CsCl-buoyant density of ?25 g/cm3.
  6. Based on the determined properties the particles are classified as phage-like Nitrobacter particles Nb1.
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11.
  1. The ATP pool in Nitrobacter winogradskyi cells was determined by means of the luciferin-luciferase enzyme system and the ADP and AMP pools were measured after enzymatic conversion into ATP.
  2. In the fist 10 min after addition of nitrite to endogenously respiring cells, which had stood for 5–16 days after completion of the nitrite oxidation, the ATP pool dropped about 60%.
  3. During the log phase the ATP pool was approx. 20–40 pmoles/5 μg cell-N. During growth it increased exponentially by 3–4 times the amount until the nitrite had been used up. Subsequently the ATP pool decreased at first rapidly and then more slowly without sinking to 0 in the first 2 months after nitrification.
  4. Nitrite oxidizing cells had an energy charge of 0.37 during the log-phase. After approx. 90% of the substrate had been used up the energy charge had reached 0.57.
  5. If the CO2 assimilation was inhibited in growing cultures by increased oxygen partial pressure, nitrite oxidation continued but the ATP pool increased.
  6. The ATP pool and the activity of the endogenous respiration decreased by more than 50% during the first hours after the substrate had been used up.
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12.
  • 1.1. A novel glycogen phosphorylase inhibitor was partially purified from crayfish hepatopancreas.
  • 2.2. The inhibitor was found only in two species of crayfish examined, and not in lobster, fresh and salt water clams, mussels or cockroaches.
  • 3.3. The inhibitor is a small protein (Mr = 23,000) which did not show proteolytic activity.
  • 4.4. Preliminary kinetic analysis of the inhibitory mechanism indicated that it bound to both glycogen and the glycogen phosphorylase protein.
  • 5.5. Inhibitor binding to glycogen resulted in a competitive inhibition pattern with respect to glycogen phosphorylase (inhibition constant of ca 10 μg/ml).
  • 6.6. The inhibitor also bound glycogen phosphorylase directly with a binding coefficient of 100 μg/ml resulting in a partially non-competitive inhibition pattern with respect to phosphate.
  相似文献   

13.
  1. Culture filtrates of heterotrophic bacteria were tested for their stimulatory effect on nitrification of three strains of Nitrobacter.
  2. Yeast extract-peptone solution, in which Pseudomonas fluorescens had grown, after removal of the cells was added to autotrophically growing cultures of Nitrobacter agilis; it caused a stimulated nitrite oxidation and growth of Nitrobacter agilis.
  3. The degree of stimulation depended on: a) the proportion of the culture filtrate to the autotrophic medium; b) the composition of the complex medium in which Pseudomonas fluorescens had been grown; c) the time the heterotrophic bacterium had been grown in the complex medium.
  4. The stimulatory effect was highest with Nitrobacter agilis, less with Nitrobacter winogradskyi and negligible with Nitrobacter K 4.
  5. It was possible to adapt nitrifying cells of Nitrobacter agilis to higher concentrations of yeast extract and peptone. After the nitrite had been completely oxidized the cell-N still increased up to 30% before growth stopped.
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14.
  1. The fine-structure analysis of the hydrocarbon oxidizing microorganism, Acinetobacter sp., demonstrated a cytoplasmic modification resulting from growth on paraffinic and olefinic hydrocarbons.
  2. Intracytoplasmic hydrocarbon inclusions were documented by electron microscopy with chemical identifications obtained by gas chromatography and X-ray diffraction.
  3. These results demonstrate the ability of a micro-organism to accumulate hydrocarbon substrates intracellularly which, in turn, indicates transport across the cell membrane.
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15.
The present study was undertaken in order to investigate the effects of sodium selenite on:
  1. The growth of rat pituitary GH4C1 cells;
  2. The nuclear T3 receptor gene expression;
  3. The cytoplasmic protein phosphorylation; and
  4. The prolactin secretion in rat pituitary GH4C1 cell line.
Sodium selenite (up to 2.5 μM) has no inhibitory effect on GH4C1 cell proliferation as well as the prolactin secretion. On the other hand, 0.5 μM sodium selenite significantly decreases the rate of mRNA synthesis and/or degradation of both, the α1 form of the T3 receptor (TRα1) and the α2 isoform of the T3 receptor. At 1 μM of sodium selenine, significant changes in the electrophoretic profile of low molecular mass cytoplasmic proteins were found, moreover, sodium selenite (1 μM) also considerably affects phosphorylation of a higher molecular mass proteins. The results based on the in vitro experiments suggest that sodium selenite may affect specific processes at the pretranslational level as well as it may also take part in processes of posttranslational modification of protein(s), the cell vitality and the cell growth remaining unchanged.  相似文献   

16.
  1. During an investigation of the physiology of Azotobacter vinelandii with particular reference to polysaccharide formation, a suitable medium which was precipitate-free was developed by adding EDTA at a concentration of 50 mg/l to a basal medium containing one of eight different carbohydrates as sole carbon source.
  2. Acetylated alginate was always produced by the organism when cultured under defined conditions, regardless of the carbohydrate source incorporated in the basal medium.
  3. When EDTA was added to the medium, the bacteria produced acetylated polyuronides with a preponderance of mannuronic acid residues.
  4. A comparison of the infrared spectra of the alginate produced by Azotobacter vinelandii and the affect of EDTA upon the mannuronic acid/guluronic acid ratios of the alginate are reported.
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17.
  1. Succinic acid is formed in amounts of 0.2–1.7 g/l by fermenting yeasts of the genusSaccharomyces during the exponential growth phase. No differences were observed between the various species, respiratory deficient mutants and wild type strains.
  2. At low glucose concentrations the formation of succinic acid depended on the amount of sugar fermented. However, the nitrogen source was found to be of greater importance than the carbon source.
  3. Of all nitrogen sources, glutamate yielded the highest amounts of succinic acid. Glutamate led to an oxidative and aspartate to a reductive formation of succinic acid.
  4. A reductive formation of succinic acid by the citric acid cycle enzymes was observed with malate. This was partially inhibited by malonate. No evidence was obtained that the glyoxylate cycle is involved in succinic acid formation by yeasts.
  5. Anaerobically grown cells ofSaccharomyces cerevisiae contained α-ketoglutarate dehydrogenase. Its activity was found in the 175000 x g sediment after fractionated centrifugation. The specific activity increased 6-fold after growth on glutamate as compared with cells grown on ammonium sulfate.
  6. The specific activities of malate dehydrogenase, fumarase, succinate dehydrogenase, succinylcoenzymeA synthetase, α-ketoglutarate dehydrogenase and glutamate dehydrogenase (nicotinamide adenine dinucleotide dependent) were determined in yeast cells grown on glutamate or ammonium sulfate. Similar results were obtained with a wild type strain and a respiratory deficient mutant. The latter did not contain succinate dehydrogenase.
  7. In fermenting yeasts succinic acid is mainly formed from glutamate by oxidation.
  相似文献   

18.

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

  1. 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.
  2. 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).
  3. Time reversal symmetry. The well-known Wigner's transformation determines the microscopic reversibility.
  4. 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.
  5. 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

  1. From the universal reversible time, an additional breaking generates the oriented time, both in the astronomical and in the living matter.
  2. Irreversibility for the environment. We refer to Prigogine and Stengers (1988).
  3. 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.
  4. Negative times. Taking into account the fuzzy character of the time reversed 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.
  5. 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

  1. That were not understandable, if time was only a frame, in which change occurs. Taking chance 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.
  2. Time modulation. Let us consider the dy1...dyi...dyp changes in the variables of the systems, 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 (y) ?1
  3. 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.
  4. 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).
  5. 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

  1. The three followings correspond to the more trivial time consumption.
  2. 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.
  3. 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.
  4. Lifetime. The dead-birth rythm 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.
  5. The plan of the alchemist. Indefinitely life has fascinated individuals. Do the human species becomes better adapted by a longer life?

Conclusions

  1. Atoms of time could exist.
  2. Biological time is defined by the breaking of five generalized symmetries, namely: Minkovski's space symmetry, reversibility, homogeneity, rhythmicity, generations reproduction.
  3. Environment and medium determine non relativistic, oriented, structured time.
  4. 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.
  5. Three fundamental particle-vacancy reciprocities admit a part of reversibity. Irreversibility governs the all others phenomena.
  6. Time is produced chemically.
  7. A new perspective is the connection between chemical equilibria and rhythms including the time of the life.
  相似文献   

19.

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

  1. 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.
  2. 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).
  3. Time reversal symmetry. The well-known Wigner's transformation determines the microscopic reversibility.
  4. 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.
  5. 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

  1. From the universal reversible time, an additional breaking generates the oriented time, both in the astronomical and in the living matter.
  2. Irreversibility for the environment. We refer to Prigogine and Stengers (1988).
  3. 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.
  4. 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.
  5. 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

  1. 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.
  2. 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)
  3. 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.
  4. 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).
  5. 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

  1. The three followings correspond to the more trivial time consumption.
  2. 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.
  3. 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.
  4. 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.
  5. The plan of the alchemist. Indefinitely life has fascinated individuals. Do the human species becomes better adapted by a longer life?

Conclusions

  1. Atoms of time could exist.
  2. Biological time is defined by the breaking of five generalized symmetries, namely: Minkovski's space symmetry, reversibility, homogeneity, rhythmicity, generations reproduction.
  3. Environment and medium determine non relativistic, oriented, structured time.
  4. 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.
  5. Three fundamental particle-vacancy reciprocities admit a part of reversibility. Irreversibility governs the all others phenomena.
  6. Time is produced chemically.
  7. A new perspective is the connection between chemical equilibria and rhythms including the time of the life.
  相似文献   

20.
  1. Phage-like particles Nb1 isolated from cells of Nitrobacter agilis were characterized after freeze etching and after treatment by fixation agents.
  2. Ethanol-acetic acid fixed particles can be digested by the proteolytic enzyme papain.
  3. Ethanol-acetic acid fixed particles show a loss in mass and volume after treatment with DNase. Under the same conditions RNase has no influence.
  4. The chemical composition of the phage-like particle Nb1 is discussed.
  相似文献   

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