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1.
  1. This investigation demonstrates the presence of three different species in Hessen (West Germany). By means of three maps the recent distribution is demonstrated.
  2. Astacus astacus is still present in Hessen in small populations.
  3. Austropotamobius torrentium is the rarest species and was recorded only in the Taunus-, Spessart- und Odenwald mountains.
  4. Oronectes limosus, in the rivers Rhein and Main numerous before 1950, has become scarce. In the river Fulda there have been only two recordings in 1958.
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2.
  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.
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3.
Forest regeneration in the vegetation complex of the submontane belt in the Southern Alps involves the active participation ofOstrya carpinifolia woods and their wood edge communities. The corresponding syndynamical processes are described by employing phytosociological, phytogeographical and ecological methods. It is concluded that:
  1. The communities of the grassland-wood transition are of major importance in the successional developments in this man-made vegetation complex.
  2. Many species occurring in the region of the deciduous forests of Eurasia find their refuge in such transitional communities and are supposed to play an important part in the succession.
  3. Ostrya carpinifolia is considered as an early successional tree species.
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4.
M. Hickman 《Hydrobiologia》1974,45(2-3):199-215
  1. The epipelic algal standing crops were increased by the discharge of thermal effluent into Lake Wabamun, particularly in the discharge canal at station (03–04) and 05.
  2. The increase in the standing crop size of the epipelon was due to Oscillatoria amoena and O. borneti in the heated area, while the discharge canal provided the inoculum of the algae for the heated area of the lake.
  3. At station (03–04) the increased standing crop size was also a function of increased light penetration to the sediment due to the heated effluent keeping an area of the lake free of ice during the winter.
  4. The species composition of the diatoms was similar at all stations except in the discharge canal where there was a reduction in the number of diatom species.
  5. Navicula cuspidate developed best in the discharge canal in the summer where water temperatures of 31°C were recorded.
  6. Amphora ovalis var. pediculus was the dominant diatom species during the winter under ice-cover.
  7. The heated effluent had no effect upon the standing crop or species composition of the epipsammon.
  8. Results obtained from the sediment core study showed that the shallow littoral zone of the lake is very disturbed due to wind-induced wave action.
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5.
Dynamics of abundance and reproductive cycles of limnophileous triclads (Turbellaria) from little ponds.
  1. Studying 18 little ponds in Lower Southern-Saxonia (West-Germany), in 14 ponds seven triclad-species were found.
  2. Phagocata vitta occurs from October to July in 1–2 generations. In the area the species reproduces by fissipary. Maximum abundances and rates of reproduction are reached in December and January. In the ponds, where P. vitta and Dugesia polychroa live together, there is no competition between the two species.
  3. After dry periods Dendrocoelum hercynicum emigrates from interstitial habitats as facultative inhabitant of surface-waters.
  4. In low abundances Dendrocoelum lacteum lives in one pond only. The breeding period (production of cocoons) lasts from January to March. Low densities of this species are probable caused by interspecific food-competition with Polycelis nigra.
  5. Likewise, Dugesia tigrina inhabits only one pond. The species is competitive to P. nigra at temperatures of about 20°C. High abundances in the months July to October fall together with high fissipareous-rates.
  6. Dugesia polychroa occurs in low densities over the year or dependent on dry-periods. Cocoons are produced between March and May, in low numbers till autumn.
  7. In the stagnant pond Bursfelde Polycelis nigra is the absolute dominant triclad-species with densities of up to 800 individuals/0,I m3. The maximum-abundances are caused by two intense reproductive periods in spring and autumn, together with optimum temperatures and food conditions.
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6.
  1. The chimpanzee vocal system is an emotionally linked vocal response developed on a standard pre-symbolic primate system.
  2. Differences in number of sounds recorded by different observers may be due to personal choice, or due actual presence or absence of certain sound types in different living situations. Further research is needed in this case before comparisons can be made.
  3. Idiosyncratic use of certain signals may serve as a basis for growth of local dialects in different areas. Spread of such dialects may be related to the amount of respect accorded to dominant animals. More study may shed light on the growth and development of pre-symbolic systems.
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7.
U. H. Mane 《Hydrobiologia》1975,47(3-4):439-451
  1. The neutral red technique was employed to study the rate of filtration in Katelysia opima.
  2. The weight specific water filtration was found to be greater for younger clams compared to the older ones.
  3. The rate of water filtration increased with decreasing salinity.
  4. Water filtration was found to increase as temperature increased, reaching a maximum at 35°C. but then sharply decreasing at 39°C.
  5. Light had no significant effect on the rate of filtration.
  6. Suspended matter was found to affect the rate of water filtration.
  7. The rate of filtration was low at high pH and high in low pH.
  8. The rate of water filtration was found to be faster during high tide than during low tide.
  9. The presence of the parasitic crab, Pennotheris sp., in the mantle cavity of clams had a marked effect on the particle filtration.
  10. Accidental cut of the siphon tips had no effect on the rate of filtration.
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8.
  1. At 20°C, fish starved for various durations took less food than unstarved fish. At 28°C, 20-day starved fish alone consumed more food.
  2. The maximum feeding was during the second ten days at 28°C but in the first ten days at 20°C.
  3. Absorption efficiency was unaffected by temperature and starvation.
  4. Absorption rate reflected feeding rate.
  5. At 28°C the conversion efficiency was high for the ten-day starved fish but at 20°C the 30-day starved fish showe high conversion efficiency.
  6. Conversion rate is governed not only by feeding rate but also by conversion efficiency.
  7. At 28°C the 20-day starved fish alone compensated for loss of energy, total and protein nitrogen. At 20°C the loss was compensated for by all fish.
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9.
  1. We are studying the neural basis of consummatory feeding behavior in Aplysia using intact, freely moving animals.
  2. Video records show that the timing of radula closure during the radula protraction-retraction cycle constitutes a major difference between ingestion (biting or swallowing) and rejection. During ingestion, the radula is closed as it retracts. During rejection, the radula is closed as it protracts.
  3. We observed two patterns of activity in nerves which are likely to mediate these radula movements. Patterns I and II are associated with ingestion and rejection, respectively, and are distinguished by the timing of radula nerve activity with respect to the onset of buccal nerve 2 activity.
  4. The association of ingestion with pattern I is maintained when the animal feeds on a polyethylene tube, the same food substrate used to elicit rejection responses. Under these conditions, pattern I is associated with either swallowing or no net tube movement.
  5. Most transitions from swallowing to rejection were preceded by one or more occurrences of pattern I in which there was no net tube movement, suggesting that these transitions can be predicted.
  6. Our data suggest that these two patterns can be used to distinguish ingestion from rejection.
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10.
  1. The main pathway of the anaerobic metabolism of l-malate in Saccharomyces bailii is catalyzed by a l-malic enzyme.
  2. The enzyme was purified more than 300-fold. During the purification procedure fumarase and pyruvate decarboxylase were removed completely, and malate dehydrogenase and oxalacetate decarboxylase were removed to a very large extent.
  3. Manganese ions are not required for the reaction of malic enzyme of Saccharomyces bailii, but the activity of the enzyme is increased by manganese.
  4. The reaction of l-malic enzyme proceeds with the coenzymes NAD and (to a lesser extent) NADP.
  5. The K m-values of the malic enzyme of Saccharomyces bailii were 10 mM for l-malate and 0.1 mM for NAD.
  6. A model based on the activity and substrate affinity of malic enzyme, the intracellular concentration of malate and phosphate, and its action on fumarase, is proposed to explain the complete anaerobic degradation of malate in Saccharomyces bailii as compared with the partial decomposition of malate in Saccharomyces cerevisiae.
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11.
  1. The daily ration required to maintain a population growth rate, r m, of zero (threshold ration) increased with increasing Asplanchna body mass. This relationship is described by the equation T=0.342 W0.797 where T=threshold ration (μg day-1 dry mass) and W=Asplanchna body mass (μg adult-1 dry mass).
  2. The threshold ration of large campanulate morphs of A. silvestrii was 3.7 times greater than that of conspecific saccate morphs suggesting that campanulates may be restricted to food-rich habitats.
  3. The daily ration required to maintain r m that is half the maximal population growth rate increased with increasing Asplanchna body mass and is described by the equation H=1.107 W1.103 where H=ration level and W=Asplanchna body mass. This population growth characteristic may reflect adaptations of rotifers to resource level.
  4. The relationships between ration level, food concentration, and Asplanchna body mass do not support the predictions of the size-efficiency hypothesis but are consistent with observed patterns of species distribution in nature.
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12.

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   

13.
  1. A diurnal study of inland fresh water lake has been made with respect to physical and chemical properties and the plankton.
  2. Chlorides have followed the total carbonates while dissolved oxygen and pH have shown no relation.
  3. Microcystis has followed no definite pattern of diurnal movement.
  4. All crustaceans, some of the rotifers andTrachelomonas perform considerable diurnal movement in the course of a twenty four hour period.
  相似文献   

14.
  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.
  相似文献   

15.
Chua Thia-Eng 《Hydrobiologia》1973,43(3-4):505-533
  1. An ecological study of the Ponggol Estuary was conducted from July 1965 to June 1966 and the seasonal data on physical, chemical and biological characteristics were presented.
  2. The Ponggol River represents a short, narrow and shallow estuary in Singapore. The river mouth is open throughout the year and water from eastern Johore Straits drains in twice a day at high tide. The upper reach, however, is left exposed at low tide.
  3. The Ponggol River was classified as a vertically and laterally homogeneous estuary and was found to exhibit a mesohaline to polyhaline environment.
  4. Significant hydrological gradients from the river mouth 10 the upper reach were noted in the river system. Salinity, dissolved oxygen and pH increased towards the mouth of the river and other parameters such as nutrients, dissolved organic matter and turbidity increased towards the source.
  5. Although the river received organic pollutants at the upper reach the estuary was able to discharge them fairly rapidly through regular flushing by the tides. The transient rise of organic matter did not appear to impart any serious affect on the biota in the estuary.
  6. Over 98% of the phytoplankton consisted of diatoms, most of which were brought into the estuary from eastern Johore Straits. Freshwater forms were relatively few.
  7. Phytoplankton biomass was considerably higher than the adjoining waters. and was reduced at the upper reach due to high turbidity of the water.
  8. 80% of the zooplankton was composed of dinoflagellates,Difflugia, copepods and bivalve larvae dominating at all sections of the estuary.
  9. Percentage composition of the zooplankton showed that dinoflagellates and copepod nauplii predominated at high tide whileDifflugia and bivalve larvae were abundant at low tide.
  10. Zooplankton standing crop, in general, was higher towards the source at high tide but the reverse was found at low tide, i.e. standing crop increased towards the river mouth. This was attributed to the process of concentration.
  11. Species composition of zooplankton was found to be more or less similar to that of the eastern Johore Straits.
  12. The nekton consisted predominantly of small and juvenile fish. Close correlation of fish and copepods was found to be statistically valid and it was concluded that the fish entered the estuary to feed rather than to spawn.
  13. The squids formed an important catch of the beach seine unit and were caught throughout the year.
  14. The fish population could be grouped into four categories: estuarine components, euryhaline components, marine components and migratory components.
  15. Benthic invertebrates were abundant. Commercially important species consisted of prawns,Metapenaeus andPenaeus, and crabs,Neptunus pelagicus andScylla serrata.
  16. The river bed was inhabited predominantly by molluscs and the distribution resembled that of the sheltered shore of muddy-sand type.
  相似文献   

16.
  1. Previous work on the methods employed for the determination of the breeding season of shipworms is briefly reviewed.
  2. The method adopted for studying the reproductive cycle by using the “gonad index” is described.
  3. The reproductive cycle of Nausitora hedleyi is described in detail based on a study of the gonad index of different sexes collected at monthly intervals from the estuarine environment of Cochin harbour.
  4. The fact that breeding is restricted as marked by seasonal activity is shown from the size and activity of the gonad during the different months of the year.
  5. The environment, and the hydrographic conditions prevailing in the habitat of N. hedleyi in the Cochin harbour are described.
  相似文献   

17.

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   

18.
  1. The phytoplankton cycle off Lawson's Bay, Waltair follows a bimodal pattern with a major peak during March–May; a minor peak during October–November months and with a low production during the summer months i.e., June–August.
  2. During the summer months of 1957, 1958, 1960 and 1962 dumping of dredged spoil from the entrance channel of the harbour into the sea resulted in a natural enrichment of waters.
  3. Following this enrichment, there was a qualitative and quantitative increase in the phytoplankters thus leading to the development of a bloom.
  4. Only Thalassiosira subtilis and Chaetoceros curvisetus commonly bloomed during the four years.
  5. The increase in gross production which varied from 3–13 fold and the high photosynthesis-respiration ratios 5.1 to 10.5 indicated that the bloom populations were in a healthy state.
  6. The decrease of the populations to the initial levels suggests that some unknown factor, other than those investigated must have been operating.
  7. Consequences of eutrophication of different origins on stimulation of phytoplankton production are briefly discussed.
  相似文献   

19.
The leaf life span, leaf habit (evergreenness and deciduousness), and species diversity of trees were simulated by a cost-benefit model of leaf longevity (Kikuzawa 1991), using monthly mean temperature values and their decreasing rate with altitude of 6°C with 1000 m of sites of different latitude and altitude in eastern Asia. Numbers of tree species in tropical regions with different lengths of favorable period for photosynthesis were also simulated. The following results were obtained by the model simulation.
  1. In tropical areas, evergreen forests predominate from lowlands to the altitudinal limit of forests.
  2. However, leaf longevity is shorter in the lowland than that at a higher altitude.
  3. Percentages of deciduousness are high in mid latitude, and the percentages of evergreenness again increase in even higher latitude, resulting in a bimodal distribution in percentages of evergreenness with increasing latitudes.
  4. Altitudinal distribution of percentages of evergreenness and deciduousness in mid latitude duplicates the latitudinal distribution. In low altitudes, percentages of evergreenness are high. But in mid altitudes, percentages of deciduousness become high, in even higher altitudes, however, evergreenness again predominates.
  5. Number of species is highest in the non-seasonal tropical region and decreases towards seasonal tropics and higher altitudes and latitudes.
  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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