Energy metabolism and body temperature in 13 sunbird species (Nectariniidae)

• 1.1. Diurnal cycles of body temperature, T_b, and energy metabolism, M, at different ambient temperatures (T_a: +5 −+ 32°C) were tested in 13 sunbird species from various habitats and of different body masses (5.2–14.2 g) including one of the smallest passerines, Aethopyga christinae.
• 2.2. Resting M-level (night) reaches T_a-dependent mean values of 54% (+5°C) and 49% (+25°C) of activity M-levels (day). Expected level is ca 75%.
• 3.3. Resting metabolic rate of sunbirds lies within the range of theoretically expected values for birds.
• 4.4. Mean linear metabolism-weight regression of the night values follows: M = 0.102 × W^0.712 (M = energy metabolism in kJ/hr and W = body mass in g).
• 5.5. Thermal conductances, T_c, are lower (−24%) than the predicted values. This is caused by a decrease of T_b at low T_a. Mean nocturnal T_c is 3.2 J/g × hr × °C, mean day-time value is 4.3 J/g × hr × °C.
• 6.6. The zone of thermoneutrality is, in most species, within a T_a-range of 24–28°C.
• 7.7. Normal day and night levels of T_b are in the same range as reported for other birds of the same weight class. T_b decreases slightly with falling T_a (partial heterothermia). Lowest recorded T_b was 34.2°C.
• 8.8. No species tested showed any sign of torpor at night, independent of T_a, body mass or habitat origin.

     

Body temperature in the mouse,hamster, and rat exposed to radiofrequency radiation: An interspecies comparison

• 1.1.|Colonic temperatures of BALB/c and CBA/J mice, golden hamsters, and Sprague-Dawley rats were taken immediately after exposure for 90 min to radiofrequency (RF) radiation.
• 2.2.|Exposures were made in 2450 MHz (mouse and hamster) or 600 MHz (rat) waveguide exposure systems while the dose rate, specific absorption rate (SAR), was continuously recorded. Experiments were performed on naive, unrestrained animals at ambient temperatures (T_a) of 20 and 30°C.
• 3.3.|Body mass and T_a) were found to be significant factors in influencing the threshold SAR for the elevation of colonic temperature. The threshold SARs at T_a's of 20 and 30°C were respectively: 27.5 and 12.1 W/kg for the BALB/c mouse; 40.7 and 8.5 W/kg for the CBA/J mouse; 8.7 and 0.61 W/kg for the golden hamster; and 1.58 and 0.4 W/kg for the Sprague-Dawley rat.
• 4.4.|The relationship between threshold SAR or SAR for a 1.0°C elevation in colonic temperature vs body mass were linearly and inversely related on a double logarithmic plot. The results of this study suggest that the thermoregulatory sensitivity to RF radiation in these rodent species is heavily dependent on body mass and T_a.

     

Specific dynamic action (SDA) in the supralittoral isopod,Ligia pallasii: Relationship of growth to SDA

• 1.1. The relationship of Specific Dynamic Action (SDA) to growth was examined in the supralittoral isopod Ligia pallasii using a seaweed diet fed at different rations.
• 2.2. Animals increased in live weight by 33% on an ad libitum or 100% diet and by 2% on a 20% ration over a 10-week period.
• 3.3. Weight-specific VO₂ was significantly higher in animals eating the 100% diet than in ones eating the 20% diet. Decline in VO₂ with time in animals on the 20% diet was probably due to poor health associated with a maintenance ration.
• 4.4. SDA per unit weight of food eaten was 18% higher in the 20% diet group than in the 100% one, and values remained constant over time in both groups.
• 5.5. k₁ growth efficiencies (production/consumption) were higher in animals on 100% ration than in ones on 20% ration. Efficiencies declined with time in both diet-groups and fell below zero in the 20% ration-group, coincidental with weight-loss in some of the animals.
• 6.6. Overall SDAs for the 10-week period were positively correlated with growth (r₂ = 0.77), but there was no way to separate this from amounts eaten as an effect on SDA.

     

Charakterisierung eines phagenähnlichen Partikels aus Zellen von Nitrobacter

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.

     

In vitro effects of sodium selenite on nuclear 3,5,3’-triiodothyronine (T3) receptor gene expression in rat pituitary GH4C1 cells

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.     

Growth of a floating aquatic weed,Salvinia under standard conditions

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.

     

Charkterisierung eines phagenähnlichen Partikels aus Zellen von Nitrobacter

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.

     

Composition chimique elementaire des populations naturelles de Sphaeroma hookeri (Crustace: Isopode Flabellifere). Aspect spatio-temporel

1. Elemental chemical composition of Sphaeroma hookeri Leach of different natural populations from Camargue (Rhône delta) and from the Bassin de Berre (near Marseilles), was studied on samples taken the same day in different populations and on samples collected at different seasons in the same population.
2. Individual analyses of carbon, hydrogen and nitrogen were performed with a Perkin Elmer elemental analyzer. Total inorganic content was obtained for each specimen by weighing the residue after the output of the analyzer.
3. Relative growth in ash, carbon, hydrogen and nitrogen content of the different populations samples was compared by means of Reeve's statistical method.
4. Chemical allometry lines of each population are given. Variability of growth coefficients or mean values in a given population appears from several samples taken in the course of the year.
5. The differences in slope and position have been tested and their significance stated.
6. Growth coefficients of ash, carbon, hydrogen and nitrogen contents show a certain variability among the different populations. But these differences are not always significant owing to the dispersion of the data, a result of the wide individual variation within a population.
7. Much greater significant differences appear from relative positions of the growth lines, and these seem to be due to some ecological factors, among which, for instance, nutriment can lead to a large difference in carbon content.
8. Within a given population no significant difference appears in the growth coefficients of ash, carbon, hydrogen or nitrogen content and therefore the obtained values characterize each population.

     

Distribution of carbon,nitrogen and phosphorus in a moss community-soil system developed on a cold desert in Antarctica

The distributions of carbon, nitrogen and phosphorus in a moss community-soil system developed on a naked region in Rundvågskollane (69⁰50'S, 39⁰09'E), East Antarctica, were investigated in order to analyze the flow of matter in an Antarctic terrestrial ecosystem.

1. The moss community was formed from many moss blocks of different sizes and was composed ofBryum pseudotriquetrum (Hedw.) Gaertn., Meyer et Scherb.,Ceratodon purpureus (Hedw.) Brid. andGrimmia lawiana J. H. Willis. The surface of the community was covered with cyanobacteria.
2. It was estimated that nitrogen fixed by cyanobacteria flowed from these organisms to the moss and that little nitrogen was transported within the moss body.
3. A large amount of phosphorus existed in the soil. The moss community had a high phosphorus content although the amount itself was relatively little due to the small phytomass.
4. It seems that absorption of phosphorus from soil is difficult for moss, because of the paucity of water necessary for the movement of phosphorus and the suppressed growth of moss due to the arid conditions.

     

Muscle GSH-Px activity after prolonged exercise,training, and selenium supplementation

A double-blind study of the effects of supplementing with selenium vs. placebo on the physiological responses to acute and chronic exercise was conducted in 24 healthy, nonsmoking males, mean age 22.9±2.1 yr, randomly divided into two groups of 12 (Pla/Sel). After a controlled period in the absence of training, all subjects were put on an individualized endurance training program with the same rules of progression and overload (3 sessions/wk×10 wk). Supplementation, either real (240 μg of organic selenium/d in Sel group) or imaginary (Pla group) was administered during the same period. In each of the conditions Pre- and Post- (training ± sel supplementation), muscle, plasma, and systemic parameters were determined before (BF) and after (AF) acute exercise, involving the repetition of muscle work cycles separated by 5-min recovery periods, combining 20 min at 65% and a maximal duration of 100% VO₂ max of running on a treadmill, leading the subjects to exhaustion between 2 h 40 min and 3 h 30 min. Changes in parameters as a function of three independent variables:

1. Acute exercise (E);
2. Chronic exercise (T); and
3. Selenium supplementing (S)

were tested with ANOVA and the Student\rsst-test on paired series. Among the variables examined, muscle glutathione peroxidase (GPx) presented a remarkable behavior. Enzymatic activity:

1. Decreased significantly (p<0.05,n=24) between the beginning and the end of acute exercise: 29.6±12 vs. 20.8±8.1 IU·g protein^?1 in Pre conditions;
2. Remained at the same level in resting conditions between the beginning and end of training (from Pre to Post) regardless of the group: 33.5±10.8 vs. 32.3±19.8 and 25.7±12.4 vs. 23.5±10.2 IU·g protein^?1 in Pla and Sel subjects, respectively; and
3. Increased from 23.5±10.2 to 37.3±28.5 (P=0.057) during acute exercise in Post-conditions (after training) in supplemented subjects (Sel group).

The situation was as if acute exercise played the role of allosteric stimulator of the GPx reaction in muscle.     

Steering by echolocation: a paradigm of ecological acoustics

1. Flights of three big brown bats (Eptesicus fuscus) landing on a hand and catching a suspended mealworm were video analysed.
2. Results were consistent with the bats using the same basic control procedure in the quite different approach tasks — namely keeping τ(r) = k _rand τ(a)τ(r) = k _αr. Here r is the current distance to the destination; α is the angle between the current direction of the destination and the goal direction of final approach (β _min); τ(r) = r/r, $\tau (\alpha ) = \alpha /\dot \alpha $ ; and k _r, k _αr are constants.
3. The bats were each quite consistent on a particular task (hand or mealworm) in the values they used for the control parameters k _r, k _αrand β _min. However, different values were used in the two tasks, which reflected the different behaviour required at the destination. Flights to hand required twisting and landing upside down and approach angle β _min was closer to vertical and k _rwas smaller and corresponded to decelerating nearly to a stop. In contrast, the mealworms were caught in mid flight and approach angle β _min was shallower and speed of approach was about constant.
4. τ(r) might be registered acoustically by τ(echo-delay) or by τ(echo-intensity). τ(α) might be registered by the bat's directional hearing and gravity sense.
5. The bats learned the tasks easily, suggesting that the control procedure they used in the experiments was part and parcel of the natural skills they had developed in the wild.

     

Energy conservation in Bacillus megaterium

1. The respiratory chain energy conservation systems of Bacillus megaterium strains D440 and M have been investigated following growth in batch and continuous culture. Respiratory membranes from these strains contained cytochromes b, aa ₃ , o and b, c, a, o, respectively; both readily oxidised NADH but neither showed any pyridine nucleotide transhydrogenase activity.
2. Whole cells of both strains exhibited endogenous →H^-/O ratios of approximately 4; when loaded with specific substrates the resultant →H⁺/O ratios indicated that proton translocating loops 1 and 2 were present in strain D440 and that loops 2 and 3 were present in strain M.
3. In situ respiratory activities were measured as a function of dilution rate during growth in continuous culture. True molar growth yields with respect to oxygen (Y _{O 2}) of approximately 50 g cells·mole oxygen^-1 were obtained for most of the nutrient limitations employed. Average values for Y _ATP of 12.7 and 10.8 g cells·mole ATP equivalents^-1 were subsequently calculated for strains D440 and M respectively.
4. Energy requirements for maintenance purposes were low in energy-limited cultures but were substantially increased when growth was limited by nitrogen source (NH ₄ ⁺ ). Under the latter conditions there is probably a partial uncoupling of energy-conserving and energy-utilising processes leading to energy wastage.

     

Purification and properties of aldehyde dehydrogenase from Aspergillus nidulans

• 1.1. Aspergillus nidulans produces aldehyde dehydrogenase (ALD-DH) only when grown in the presence of ethanol, threonine or acetoacetic acid as inducer. Enzyme formation is inhibited by glucose in the growth medium.
• 2.2. ALD-DH is purified by a rapid procedure using Cibacron Blue Affinity Chromatography with specific inhibitoe elution by NAD plus 2:2′ dithiodipyridine or 2:4 disulfiram.
• 3.3. The pure native enzyme has a M_r=265,000 and a subunit M_r of 540,000. Its optimum pH is 8.5; its preferred substrate is acetaldehyde and it can use either NAD or NADP.

     

EPR characterization of oxide supported transition metal ions: Relevance to catalysis

EPR spectroscopy is a powerful tool to identify at a molecular level, the different steps of catalyst preparation, and of catalytic reactions:

1. Deposition of paramagnetic transition metal ions onto a support is monitored, and the coordination sphere of the metallic center is characterized by EPR.
2. The catalyst is also characterized after activation (thermal oxidation or reduction):

- the distribution among the different sites in zeolites can be determined;

- the dispersion of the active phase may be appreciated;

- the unsaturation degree of the active site may be evaluated using probe molecules such as water or¹³C enriched carbon monoxide.

1. The catalytic mechanisms can be investigated by studying the elementary steps of the catalytic reaction, as illustrated for methanol oxidation over Mo/SiO₂ catalysts whose EPR results have extended the reaction mechanism proposed on the basis of kinetic data. In addition, reaction intermediates may be isolated inquasi-in situ conditions as in the case of olefin oligomerization catalyzed by Ni/SiO₂ systems.

     

In vitro substrate utilization for lipid synthesis in liver explants from hyperthyroid chickens

• 1.1. Indian River male broiler chickens growing from 7 to 28 days of age were fed diets containing 12, 18, 24 and 30% protein + 0 or 1 mg triiodothyronine (T₃)/kg of diet to study energetic costs of lipogenesis and the use of various substrates for in vitro lipogenesis.
• 2.2. De novo lipid and CO₂ production were determined in the presence of [1-¹⁴C]pyruvate, [2-¹⁴q]pyruvate, [3-¹⁴C]pyruvate, [2-¹⁴C]acetate and [U-¹⁴C]alanine.
• 3.3. Oxygen consumption was determined in mitochondrial preparations to estimate the energetic costs in expiants synthesizing lipid.
• 4.4. Radiolabeled CO₂ derived from [1-¹⁴C]pyruvate was used as an estimate of coenzyme A availability in liver expiants. Lipids derived from [2-¹⁴C]pyruvate, [2-¹⁴C]acetate and [U-¹⁴C]alanine estimate relative substrate efficiency.
• 5.5. Labeled CO₂ production from [1-¹⁴C]pyruvate was greatest in that group fed a 12% protein diet and least in the group fed a 30% protein diet.
• 6.6. In addition, T₃ increased CO₂ production from [1-¹⁴C]pyruvate.
• 7.7. The production of ¹⁴CO₂ from the second carbon of pyruvate or acetate was increased by T₃.
• 8.8. The low-protein diet (12% protein) increased (P <0.05) lipogenesis.
• 9.9. Adding T₃ to the diets decreased carbon flux into lipid from all substrates, but increased CO₂ production from all substrates without changing stage 3 and 4 respiration rates in mitochondrial preparations.
• 10.10. These observations imply that coenzyme A availability may have regulated de novo lipogenesis in the present study.
• 11.11. It was also concluded that previously noted effects of T₃ on intermediary metabolism may involve metabolic pathways that do not involve changes in mitochondrial function.

     

Les brisures de symetrie du temps

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...dy_i...dy_p changes in the variables of the systems, dy={dy_i} has produced dt. We proof (eq.(1) to (4)) that time is modulated by a φ_(y) speed coefficient depending on the medium. t_modulated=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 t_modulated means repression, short t_modulated 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.

     

Survival,osmoregulatory ability,and respiration of idotea chelipes (Crustacea,Isopoda) from lake veere in different salinities and temperatures

1. An ecological and physiological study ofI. chelipes from Lake Veere, The Netherlands, was made.
2. Both osmoregulatory capacity and survival decrease with increasing temperature as well as with decreasing salinity.
3. Respiration experiments suggest that the need of energy by osmoregulatory activity may be supplied at the cost of other physiological processes, at any rate at temperatures of 10°C and higher.
4. It may be expected that, if temperatures higher than 15°C and salinities lower than 8‰ coincide, the population ofI. chelipes will be affected negatively.

     

Les brisures de symetrie du temps

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...dy_i...dy_p changes in the variables of the system, dy={dy_i} has produced dt. We proof (eq.(1) to (4)) that time is modulated by a Φ_(y) speed coefficient depending on the medium. t_modulated=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 t_modulated means repression, short t_modulated 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.

     

Function of laccase in the white-rot fungus Fomes annosus

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.

     

Biogenesis of mitochondria 19 the effects of unsaturated fatty acid depletion on the lipid composition and energy metabolism of a fatty acid desaturase mutant of

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 (C_8∶0?C_20∶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.