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1.

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   

2.

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   

3.
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.
  相似文献   

4.
  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.
  相似文献   

5.
  1. From 40 waters of the Abisko-district (Sweden, Lapland) 58 samples were collected (essentially samples from sediments).
  2. It is not possible to clear the origin of all discovered tests of sediments. The bottom of most waters was covered with mosses, from which vegetation, tests can come into the sediments. But also tests from other biotopes, can be found at the bottom.
  3. Nevertheless we can recognize typical characters of those species living in sediments. The prevalent type is the “Difflugia-type”. Those species of Centropyxis which immigrated into sediments demonstrate a trend towards the “Difflugia-type”. The immigration is possible from Aufwuchs, mosses and soils. 62,7% of the recorded tests belong to Difflugia, 17,8% to Centropyxis.
  4. The prevalent species in the sediments of the Abisko-district is Difflugia elegans var. teres, the next is D. glubolosa.
  5. A great number of investigated waters contained the oligotrophic species Centropyxis aërophila. Only one lake (Ruontenjaure) shows the association of dystrophic lakes.
  6. Some species are described taxonomically, for instance: Centropyxis nauwercki n.sp. C. nauwercki is very much like Difflugia, but is also connected with C. platystoma. The new species shows a trend from Centropyxis to Difflugia.
  7. C. aërophila can also immigrate into the Aufwuchs. There the species has membraneous tests.
  8. Geographical aspects of the sediment colonization are discussed.
  相似文献   

6.
  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.
  相似文献   

7.
  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.
  相似文献   

8.
J. Rzedowski 《Brittonia》1972,24(4):398-402
  1. -Bigelowia pyramidata Rob. & Greenm. from Oaxaca proves to be a dioecious plant and is therefore transferred to the genusBaccharis.
  2. -Baccharis matudae sp. nov. is described on the basis of material collected in Zacatecas and San Luis Potosí. The species is closely related toB. pyramidata (Rob. & Greenm.) Rzedowski.
  3. -Baccharis zamoranensis sp. nov. is described on the basis of material collected on the border of Querétaro and Guanajuato. The taxon is related toB. multiflora H.B.K., known from central and southern Mexico.
  相似文献   

9.
A novel approach has been introduced to detect the manifestation of symmetry breaking weak interactions at molecular level. In the racemic conglomerate crystallization of D, L-sodium-ammonium tartrate the effect of32P irradiation was studied by measuring the weight and optical purity of the crystalline phase as well as the size distribution of the crystallites. The high number of independent experiments (over 1000) permitted statistical analysis of the results. The following observations have been made:
  1. Beta irradiation influences the crystallization process, irradiated samples yield more crystalline material.
  2. The effect involves presumably crystal seed formation because from the irradiated solutions more and smaller crystallites are formed.
  3. The presence of beta particles induces stereoselective crystallization, the crystalline phase shows optical activity characteristic of the “unnatural” L-isomer.
  4. The above changes are attributed to the beta irradiation as the magnitude of the effects depends on the amount of added radioactivity. Optically active contaminants are highly unlikely sources of the differences between irradiated and control series.
  5. In the absence of32P the tartrate enantiomers have equal probability to form crystals, i.e., the contribution of mixing of weak interaction into the electromagnetic one is not measurable in this system.
  相似文献   

10.
S. Meguro  A. Miyawaki 《Plant Ecology》1994,112(2):101-111
The mechanical properties of broad-leaf tree species in a maritime-wind exposed habitat in central Japan were examined. The broad-leaf trees studied were Celtis sinensis var. japonica, Ilex integra, Eurya japonica, Pittosporum tobira, Euonymus japonicus and Cinnamomum japonicum. The results obtained can be summarized briefly as follows:
  1. At places with weaker wind, the number of species increased and the height of the canopy increased.
  2. The fracture strength σm showed no dependence on tree part or branch thickness, but was constant.
  3. The order of strength was Celtis sinensis var. japonica > Ilex integra > Eurya japonica > Pittosporum tobira > Euonymus japonicus > Cinnamomum japonicum, and these six species could best adapt to the wind pressure in the study area.
  4. Within species, fracture strength varied directly with wind strength.
  5. The strain εm decreased as the trunk became thicker.
  6. Within species, strain energy Um varied directly with wind strength.
  相似文献   

11.
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   

12.
T. Kamaya 《Mycopathologia》1969,37(4):320-330
Young colonies of Sabouraud's glucose agar room temperature culture ofCandida species from human isolation were suspended in distilled water. The suspension was mixed with a solution of lysozyme and incubated in a 37° C water bath. Within 3–5 hours, various species ofCandida cells showed flocculation to varying degrees which occurred at varying periods of onset. Among sevenCandida species,Candida albicans andCandida stellatoidea showed the strongest flocculation, earliest onset and most solution clarity than did any other species.Candida stellatoidea was indistinguishable fromCandida albicans in its degree of flocculation, and in the clarity of solution.Candida species may be arranged in the following order according to their decreasing positivity in flocculation:
  1. Candida albicans
  2. Candida stellatoidea
  3. Candida tropicalis
  4. Candida krusei
  5. Candida pseudotropicalis
  6. Candida parapsilosis
  7. Candida guilliermondii
  8. Saccharomyces species may be placed afterCandida guilliermondii.
It seems possible to separate theCandida species into 3 groups by the rate of flocculation, and clarity of solution. Group I.Candida albicans andCandida stellatoidea. Group II.Candida tropicalis, C. krusei andCandida pseudotropicalis. Group III.Candida parapsilosis andCandida guilliermondii. Saccharomyces specimens (S. cerevisiae and others) were placed after group III.  相似文献   

13.
Combining the results of field observations from the Eider, Elbe, Weser and Ems estuaries and laboratory experiments it was found that:
  1. in German North Sea estuaries the tidal freshwater reaches are the main habitat of the diatomActinocyclus normanii.
  2. the residence time within the tidal freshwater reaches is a key factor controlling not only seasonal and spatial densities within one estuary, but also density differences between estuaries;
  3. A. normanii is well adapted to strongly changing light situations and thus adapted to estuaries with high vertical turbulent mixing and low values of Zeu/Zmix;
  4. the downstream limit of the habitat ofA. normanii is mainly determined by light limitation rather than by hyperosmotic stress.
  相似文献   

14.
An oxaloacetate (OAA) decarboxylase (EC 4.1.1.3) has been purified 72-fold from Acetobacter aceti cells grown on ethanol, and its molecular weight was estimated to be about 80,000 by gel filtration. Several properties distinguished this enzyme from the OAA decarboxylase from A. xylinum:
  1. It was not a constitutive enzyme; the activity was 6- to 20-fold higher in cells grown on a C2 substrate (acetate or ethanol) than in cells grown on a C3 compound (pyruvate or propionate).
  2. The optimum pH was 7.5; a value of 5.6 was reported for the enzyme from A. xylinum.
  3. The enzyme did not need a divalent cation and was not inhibited by EDTA.
  4. The K mvalue for OAA was found to be 0.22 mM. It was not affected by the addition of nicotinamide adenine dinucleotide.
  5. The enzyme activity was neither inhibited by acetate nor by L-malate.
In addition, the OAA decarboxylase from A. aceti was insensitive to monovalent cations, avidin or acetyl coenzyme A.  相似文献   

15.
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.
  相似文献   

16.
  1. Thioglycolic acid, a Cu-chelating agent, totally inhibited extracellular laccase activity without affecting growth and morphology of Fomes annosus.
  2. In the presence of thioglycolic acid Fomes annosus cleaved high molecular weight lignosulfonate with a molecular weight range of 2×106 to 1000. In the absence of thioglycolic acid the polymerizing activity of laccase prevented the detection of lignosulfonate breakdown products.
  3. Oxidative polymerization of a lignin monomer, coniferyl alcohol, occurred in the presence but not in the absence of laccase activity.
  4. Catechol and guaiacol added to the medium at a concentration of 2 mmol, are normally oxidized by fungal laccase and strongly inhibit growth. Presence of thioglycolic acid prevented the oxidation of these phenols and simultaneously permitted normal growth.
  相似文献   

17.
  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.
  相似文献   

18.
The object of this work was to measure the effective proton conductance of the plasma membrane ofMicrococcus denitrificans under various conditions and to investigate possible connections between respiration and proton translocation.
  1. Pulsed acid-base titrations of suspensions ofM. denitrificans in a medium containing the permeant thiocyanate ion, or when K+ ion permeability was induced by valinomycin in a KCl medium, showed that the normal effective proton conductance of the membrane system was less than 1 μmho/cm2.
  2. A pH-overshoot artefact was suppressed by adding carbonic anhydrase.
  3. The effective proton conductance was increased by the uncoupler FCCP in the same concentration range as was required to stimulate respiration. Concentrations of FCCP above 1·5 μM inhibited respiration after an initial stimulation.
  4. The effective proton conductance in presence of 2 μM FCCP was at least 17 μmho/cm2.
  5. The quantitative relationships between the respiratory rate, the stoichiometry of respiration-driven proton translocation, and the effective proton conductance of the membrane of the cells are compatible with the suggestion that stimulation of respiration by FCCP is due to a release of back-pressure exerted by a protonmotive potential on the respiratory chain system in the membrane. Only one amongst other possible explanations of the stimulation of respiration by FCCP is, however, excluded.
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19.
  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.
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20.
  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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