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The adenine nucleotide translocation in mitochondria has previously been established as an exchange between exogenous and endogenous adenine nucleotides across the inner membrane. The specificity and the control of the exchange are examined with the following major results: The adenine nucleotide translocation is relatively specific for exogenous ADP and ATP, AMP being nearly inactive. Among other nucleotides tested, only dADP and dATP exchange with a noticeable activity. In the controlled state ADP exchanges 2–4 times faster than ATP. If simultaneously added, ADP and ATP compete for the exchange, with ADP being about tenfold more active than ATP. The specificity of the exit of adenine nucleotides in the exchange is similar to the specificity of the entrance with the difference that ADP and ATP are released with equal activity in proportion to their intramitochondrial content. AMP is released only after a slow conversion to ADP. Therefore the short time exchange is limited by the endogenous content of ADP plus ATP. The exchange is influenced by the metabolic state of the mitochondria. The ATP exchange is more variable than the ADP exchange. Two effects are elucidated: (a) the influence of the metabolic state on the relative content of AMP which inhibits both the ADP and ATP exchange (b) the coupling of the energy transfer system which inhibits only the ATP exchange. An example for case (a) is the inhibition of the ADP and ATP exchange by arsenate and an example for case (b) is the strong increase of the ATP exchange on uncoupling. The following effects are relevant to the mechanism of the control of the exchange by ATP. The stimulation of the ATP exchange by uncoupler has the same concentration dependence as the uncoupling of oxidative phosphorylation (Km [CCP] = 0.08 μM, where CCP = carbonyl‐cyanide‐phenylhydrazone). Oligomycin does not abolish the uncoupler effect on the ATP exchange. “Endogenous uncoupling” on aging of mitochondria also stimulates the ATP exchange. Valinomycin plus K+ only slightly stimulate the ATP exchange. Anaerobiosis stimulates the ATP exchange to a smaller extent than uncoupling.In competition with ADP the effects of energy transfer on ATP exchange are more strongly revealed. On uncoupling the more than tenfold preference for ADP is fully abolished. It is concluded that basically the exchange for ADP and ATP has equal specificity in forward and reverse reaction. In the controlled state a superimposed force makes the specificity asymmetric and inhibits the entrance of ATP. This control of the ATP exchange is concluded to be based on the anionic character of the adenine nucleotides. Thus the ATP4‐ex–ADP3‐in exchange is inhibited unless the charge difference is compensated for by an uncoupler stimulated H+ movement across the membrane. Furthermore an electric potential gradient appears to be effective in the controlled state which is abolished on uncoupling.

Currently used analytical tools and indicators of macroeconomic development of the country do not adequately reflect environmental concerns. We need to improve the methodological basis of macroeconomic statistics of the natural environment and its relationships with agriculture to obtain more reliable information about the condition of a particular region. The paper proposes the formulation of macroeconomic accounts from the municipal level to aggregated information at the level of region and country. For example, the assets accounts for land cover and soil resources are developed according to cartographic survey of the Borovsk district of Kaluga region. In general, the developed base map is enough to make most accounts (balance sheet) assets land and soil resources. However, for a more complete and comprehensive reflection of soil resources in physical terms it is recommended to add indicators of soil properties that represent the physical, chemical and biological characteristics of soil, like porosity, structure, pH level and microbial biomass.

Cette thèse est basée sur des simulations numériques régionales et aborde, d’un point de vue énergétique, la variabilité à Méso (O(10-100)km) et Sous-mésoéchelle (O(0.1-10)km) dans la région du Courant des Aiguilles.(i) La variabilité de sous-mésoéchelle à la transition entre les deux branches du Courant des Aiguilles (28◦E-26◦E) est dominée, en l’absence de méandres de mésoéchelle, par des tourbillons cycloniques frontaux formant un ‘vortex street’. La tension ambiante frontogénétique intensifie le cisaillement frontal qui déclenche l’instabilité barotrope menant à la génération de tourbillons de sous-mésoéchelle.(ii) Un budget modal d’Energie Cinétique des Tourbillons est développé pour caractériser les transferts d’énergie entre les différentes structures verticales. Les interactions canalisées par la topographie (3 processus) résultent globalement en une perte d’énergie pour les tourbillons de mésoéchelle plus grande que les processus de dissipation (friction au fond et vent) et une cascade verticale inverse (interactions triadiques) renforce les tourbillons de mésoéchelle dans les zones au large.(iii) Notre budget modal permet de caractériser la région du Courant des Aiguilles comme une source nette d’énergie pour les tourbillons de mésoéchelle en contradiction avec celui estimé à partir de données d’altimétrie. Cette différence vient des données d’altimétrie ne tenant pas compte de la contribution principale de la dynamique aux sources et puits d’énergie des tourbillons de mésoéchelle (partie linéaire de la dynamique agéostrophique du mode barotrope et du 1er mode barocline). This dissertation is based on regional numerical simulations and addresses, from an energetic perspective, the Meso (O(10-100)km) and Submesoscale (O(0.1- 10)km) variability in the Agulhas Current region.(i) Submesoscale variability at the transition between the two Agulhas Current branches (28◦E-26◦E) is dominated, in the absence of mesoscale meanders, by cyclonic frontal eddies forming a ’vortex street’. The frontogenetic background strain intensifies the frontal shear which triggers the barotropic instability leading to submesoscale eddies generation.(ii) A modal Eddy Kinetic Energy budget is derived to characterize the energy transfers between the different vertical structures. Interactions canalized by topography (3 processes) globally result in a larger energy loss for mesoscale eddies than dissipation processes (bottom friction and wind) and an inverse vertical cascade (triadic interactions) reinforces mesoscale eddies in offshore areas.(iii) Our modal budget allows to characterize the Agulhas Current region as a net energy source for mesoscale eddies in contradiction with one inferred from altimetry data. The discrepancies come from altimetry data not accounting for the main contribution of the dynamics to mesoscale eddies energy sources and sinks (ageostrophic linear part of the dynamics of the barotropic and 1st baroclinic modes).

• Key message Insurance might be an efficient tool to strengthen adaptation of forest management to climate change. A theoretical model under uncertainty is proposed to highlight the effect, on adaptation decisions, of considering adaptation efforts in forest insurance contracts. Results show that insurance is relevant to increase adaptation efforts under some realistic conditions on forest owner’s uncertainty and risk preferences, and on the observability or not of adaptation efforts. • Context One of the challenges of forest adaptation to climate change is to encourage private forest owners to implement adaptation strategies. • Aims We suggest the analysis of forest insurance contracts against natural hazards as a vector to promote the implementation of adaptation efforts by private forest owners. • Methods We propose a theoretical model of insurance economics under risk and under uncertainty. • Results Our results indicate that when climate change makes the probability of the occurrence of the natural event uncertain, then it may be relevant to include adaptation efforts in the insurance contract, leading to an increase in the adaptation efforts of risk-averse and uncertainty-averse forest owners. In addition, we show that the relevance of insurance as a vector to promote adaptation efforts is greater when the forest owner’s effort is unobservable by the insurer as compared to a situation of perfectly observable effort. • Conclusion Under some realistic assumptions, the forest insurance contract seems to be a relevant tool to encourage forest owners to adapt to climate change.

AbstractThe ethylene glycol oxidation reaction on nickel and ruthenium modified palladium nanocatalysts was investigated with electrochemical, spectroelectrochemical, and chromatographic methods. These carbon‐supported materials, prepared by a revisited polyol approach, exhibited high activity towards the ethylene glycol electrooxidation in alkaline medium. Electrolysis coupled with high performance liquid chromatography/mass spectrometry (HPLC‐MS) and in situ Fourier transform infrared spectroscopy (FTIRS) measurements allowed us to determine the different compounds electrogenerated in the oxidative conversion of this two‐carbon molecule. High value‐added products such as oxalate, glyoxylate, and glycolate were identified in all electrolytic solutions, whereas glyoxylate was selectively formed at the Ru45@Pd55/C electrode surface. In situ FTIRS results also showed a decrease in the pH value in the thin layer near the electrode as a consequence of OH− consumption during the spectroelectrochemical experiments.

Abstract Additional experimental data concerning the kinetics of Ni-Mo codeposition were obtained by investigating cathodic polarization using a rotating disc electrode. The Ni-Mo alloys were deposited from an ammonium citrate bath. The alloy deposition was controlled by activation in the case of low values of the cathode potential and by diffusion in the case of higher values. The hydrogen discharge was found to be diffusion controlled. The inductive influence of nickel results in depolarization of the reduction of molybdenum which cannot be deposited separately. An increase in the disc rotation speed caused an increase in the maximum cathode efficiency and in the molybdenum content of the alloy.

In the present study, we explored the temperature evolution and hydrogen desorption properties of the Mg50Ni50 alloy through both numerical simulation and experimental analyses. Desorption kinetics characterization was carried out using the volumetric method, specifically employing a Sievert's-type apparatus to investigate solid-gas reactions. The experiments covered a temperature range from 313 K to 353 K, with an initial hydrogen pressure of 12 bar. Simultaneously, a mathematical approach was employed to numerically investigate the temperature evolution within the hydride bed. Using COMSOL Multiphysics as a simulator, a numerical simulation was conducted based on experimental data. The study examined the impact of cooling temperature on hydride temperature evolution. Results revealed that hydrogen desorption kinetics of the amorphous Mg50Ni50 alloy are more significant compared to those of Mg2Ni compounds. Moreover, the effect of the warming temperature on the equilibrium pressure can also be observed in the hydrogen desorption isotherm curves. The experimental study of the Mg50Ni50 alloy provided activation energy data, along with determination of hydride formation enthalpy and entropy. On the other hand, we showed that the hydride temperature is maximum at the hydride-hydrogen interface within the hydride center.

Abstract The objective of this work is to evaluate the surge characteristics of an axial compressor operating under surge conditions, by using a hybrid BDF/harmonic balance method. During a surge event, a large amount of backflow occurs in the compressor. Consequently, the airflow oscillates along the axial direction at a low frequency, which can considerably damage the compressor. In this paper, a numerical investigation is performed to examine the effects of the system volume and average mass flow on the surge characteristics of a transonic high speed single stage axial compressor (stage 35) designed and evaluated at the NASA Glenn Center. The results show that the oscillation frequency of the airflow in the compressor generally ranges from 14.32–26.04 Hz during surge conditions, and both the system volume and average mass flow considerably influence the surge characteristics. For a constant average mass flow, as the system volume decreases, the oscillation frequency of the airflow in the compressor increases slightly, while the oscillation amplitude of the exit static pressure decreases significantly, and the maximum static pressure at the outlet remains nearly constant. In the case of a constant system volume, with the decrease in the average mass flow, the oscillation frequency of the airflow in the compressor gradually decreases, and the oscillation amplitude of the exit pressure increases significantly. With a further decrease in the average mass flow, the oscillation frequency stabilizes at a certain point and does not change thenceforth. Furthermore, the surge frequency obtained using the numerical method shows a same tendency with the Helmholtz frequency, but there is a considerable difference between them.