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A simple and general thermodynamic theory is applied to describe the irreversible aspects of the continuous process of functional efficiency loss, which occurs in dissipative biological structures after they reach maturity [1]. This theory, among other things, follows Prigogine [2] by considering that these dissipative structures perform their functions and carry out cyclical processes per se since they are self-organizing away from equilibrium. By using the irreversible thermodynamic theory of aging by Montemayor-Aldrete et al [1], we have obtained results such as the following: The accumulated damage that occurs in dissipative biological structures after they reach maturity, which is the product of linear loss of functional efficiency with time, leads to the law of exponential mortality rate by Gompertz. The average solar power volumetric density of frequency ν dissipated by circular molecules of radius , which reside on the inner surface of some lipid vesicles that float in the Archean oceans and that contain water and other chemical components are obtained. Such expression resembles the Stefan–Boltzmann law which describes the power radiated from a black body in terms of its temperature. Also, an expression for the volumetric density of the average entropy production rate by molecules of radius is obtained. Finally, the coupling processes that occur between the matter and heat fluxes between the interior and the exterior of lentil-shaped lipid vesicles pumped by the solar radiation action are analyzed qualitatively as well as their possible consequences in relation to the prebiotic chemical evolution of dissipative systems that can give rise to life.

A simple and general thermodynamic theory is applied to describe the irreversible aspects of the continuous process of functional efficiency loss, which occurs in dissipative biological structures after they reach maturity. Following Prigogine [G. Nicolis and I. Prigogine, Self-organization in Nonequilibrium Systems (Wiley, New York, 1997), pp. 2–3], this theory considers that these dissipative structures perform their functions carrying out cyclic processes per se since they are self-organized far from equilibrium. Starting from the theoretical fact that after biological dissipative systems reach adulthood, the functionality of their organs decreases linearly over time. We show that cumulative damage leads to the exponential law of increasing mortality rate with age for population groups, known as Gompertz’s law. The theory was applied to the determination of functional efficiency loss parameter, [Formula: see text], for 71 living beings as a function of mass covering 18 orders of magnitude. The mathematical adjustment allowed us to conclude that there is a minimum in the value of the [Formula: see text] parameter for a 23.3 kg mass which is close enough to the Homo sapiens one. We obtained useful expressions to describe the [Formula: see text] parameter for smaller masses than those of saccharomyces cerevisiae, so perhaps this theory may contribute to the study of the evolution of some dissipative pre-biological structures.

In 2013 state officials operating through the three federal government branches of Mexico mutilated the country’s constitution, privatizing upwards of seventy-five percent of the country’s hydrocarbon reserves. This article suggests that this neoliberal strategy, carried out by transnationally oriented elites operating through state apparatuses in Mexico (and promoted by officials in Washington and within the International Financial Institutions), is meant to benefit transnational capital. Such drastic change to Mexico’s legal order, we argue, in fact violated the country’s constitution and symbolized a break with the country’s earlier model of development. The federal government’s anti-constitutional behavior, specifically its violation of Article 136 of the constitution, provides a legal basis for dismissing top officials from their posts and moving toward a constitutional assembly.

Forbes Magazine published its list of leading or strongest publicly-traded two thousand companies in the world (G-2000) based on four independent metrics: sales or revenues, profits, assets and market value. Every one of these wealth metrics yields particular information on the corporate size or wealth size of each firm. The G-2000 cumulative probability wealth distribution per employee (per capita) for all four metrics exhibits a two-class structure: quasi-exponential in the lower part, and a Pareto power-law in the higher part. These two-class structure per capita distributions are qualitatively similar to income and wealth distributions in many countries of the world, but the fraction of firms per employee within the high-class Pareto is about 49% in sales per employee, and 33% after averaging on the four metrics, whereas in countries the fraction of rich agents in the Pareto zone is less than 10%. The quasi-exponential zone can be adjusted by Gamma or Log-normal distributions. On the other hand, Forbes classifies the G-2000 firms in 82 different industries or economic activities. Within each industry, the wealth distribution per employee also follows a two-class structure, but when the aggregate wealth of firms in each industry for the four metrics is divided by the total number of employees in that industry, then the 82 points of the aggregate wealth distribution by industry per employee can be well adjusted by quasi-exponential curves for the four metrics.

Human development has been based on the use of the energy resources, especially those of fossil origin (oil, gas, coal, etc.), which are not infinite and damage ecosystems; it is of paramount importance to make a transition to other alternative sources of energy. We compare and discuss many global sources of energy and their impact, based on the useful parameter called energy returned on energy invested or energy return on investment (eroi). In the long run we could expect renewed emphasis on enhanced (stimulated or hot dry rock) geothermal energy sources due to technological advances in deep drilling and the availability of this kind of energy 365 days per year and 24 hours of a day.

A simple and general theory to describe basic irreversible thermodynamic aspects of aging in all dissipative living is presented. Any dissipative system during its operation continuously loses efficiency by the production of structural or functional defects because of the second law of thermodynamics. This continuous loss of efficiency occurs on all the dissipative systems through the realization of specific functional cycles, leading to a maximum action principle of any system involving the Planck’s constant during their total dissipative operation. We applied our theory to the calculation of men and women lifespans from basal metabolic rate per unit weight and to the calculation of a new aging parameter per cycle of some human organs or physiological functions. All microscopic theory of the aging of living beings should be consistent with the second law of the thermodynamics. In other words, the operation of the biological self-organized structures only implies a delay in which the dissipative biological systems outside of equilibrium approach inexorably to the thermodynamic equilibrium obeying the second law of the thermodynamics.

A local measurement technique for the study of the kinetic processes of emerging of grains or blocks of grains from the inner volume to the free surface of superplastic materials during deformation is presented and used for the case of the Cd-Zn eutectic alloy deformed at room temperature. This technique could be used to evaluate the approximate time of fracture due to fissure or cavitation growth in samples under superplastic deformation. In principle, this technique will be useful for the development of physical procedures, which allows retarding the process of formation of low mismatch angle, , between neighboring grains, process which gives place to blocks of grains which dynamically behave as units under the shear stress action. For materials with nanocrystalline structures, such processes are expected to be higher than those of the case of microcrystalline materials.

A non-equilibrium statistical theory for aging dissipative systems formed by atoms is developed and applied to electromigration damage in conductors. A modification of Black’s mean failure time is presented. We describe the experimental relationship between the initial rate of increase in the functional damage and the electric conductor lifetime. Also, for situations where electromigration damage is mainly due to heat dissipation caused by conduction inside the conductor, it was possible to obtain a mean-field theory which yields expressions (that agree with the experimental data) for the increase of resistance with the current stressing time, in test probes of different materials, and for the total volume of hillocks as a function of the current stressing time.

The Zn–22 wt pct Al eutectoid alloy is a superplastic material which has been used in a number of experimental investigations of superplasticity. Considerable attention has been devoted to this alloy, because this material has numerous potential applications [1]. Zinc-rich aluminum alloys with: Fe [2, 3] or with Copper additions [2–5], has been of engineering interest over recent years, because the addition of some alloying elements enhances the wear resistance, elastic modulus, yield strength and corrosion resistance under the service conditions of stress and temperature without having a major effect on the superplastic behavior during production of components. The main goal of this investigation is to study the effect of grain size on the activation energy for plastic deformation, near room temperature, in a Zn–Al–Cu Alloy. The chemical analysis of the alloy used in this work was Zn– 28.7 wt pct Al–1.9 wt pct Cu. The superplastic material was obtained by extrusion resulting in a grain size 2.7 lm. A number of flat tensile specimens were prepared from this material. A set of specimens were heat treated at 548 K for 3 h, followed by rapid quenching in water at room tempeature. This treatment produce a grain size of 0.6 lm, measured by the line intercept method [6]. The experiments were conducted using two grain size specimens. Flat tensile specimens, having 1.6 cm gage length and 0.2 · 0.32 cm cross-section, were used to study creep behavior. Creep tests were carried out using a constant load machine (SATEC), which was modified to provide constant applied stress, with a variation of no more than 0.7% in the chosen stress. Stresses between 1.6 MPa and 20.5 MPa were applied to the samples producing steady state strain rates between 6.4*10 s to 1.6*10 s. The strain during the creep tests was measured with a Schaevitz linear variable differential transformer (LVDT) accurate to ±1.3*10 cm, and this information was monitored using a data acquisition system. The test temperatures ranging from 294 K to 398 K were achieved by using tungsten lamps around the specimen holder. This heating device was capable to rise to the selected temperature of the specimen within 20 s. The test temperatures were constant at the level of ±0.5 K. The plots of true strain, e, against time, t, which were obtained for specimens with grain sizes of 2.7 lm and 0.6 lm are, respectively illustrated in Figs. 1 and 2. Examination of Fig. 1 corresponding to samples with 2.7 lm has shown that the creep curves exhibit a very short decelerating primary stage followed by a steady state stage; and also exhibit that primary transient strain increases with increasing the applied stress. Unlike our experimental J. D. Munoz-Andrade has written this article for partial fulfillment of the Individualized Doctorate Program at the Facultad de Ingenieria, Universidad Central de Venezuela, Caracas, Venezuela.

We investigate the effect of an electric field applied transverse to the axis of cylindrical symmetry of a hollow cylindrical quantum wire on the energy ground state of the electrons in this wire. We investigate how the shift in the energy with field depends upon the ratio of the outer and inner radii of the hollow wire.

We obtain an approximated expression for steady state distance headway that takes into account all the physical processes involved in real braking. This simple approximated formula gives a good description of the empirical data. The peculiarity of this approximation is that at small vehicle speed the gap increases with an increase in speed sharper than a linear function, whereas in most models this function gap vs. speed is a linear function or weaker than the linear function. A new concept of the production rate of entropy due to traffic flow has been presented. With the use of such a concept the percentage of increase in the fuel consumption rate due to velocity fluctuations on the traffic flow is easily determined. The same percentage of increase in the fuel consumption rate could be obtained as a function of the fluctuations on the CO2 production rate due to the traffic flow. The practical applications of such analysis are obvious. It is possible that the use of the simple model developed here could be very useful in the conceptual scheme of the three-phase traffic theory.

By applying the theoretical model of Mohamed and Langdon [1] the activation energy for high temperature plastic deformation of TiCx single crystals as a function of C : Ti atom ratios is obtained. It is found that the values for the activation energy at the critical resolved shear stress are lower than the lattice self-diffusion data for carbon, except for x=0.75. At this concentration a peak in the activation energy, 560 KJ, mol-1, which is about 75% of that for lattice self-diffusion of Ti in TiC, appears. This situation is due to an ordering hardening caused by a contraction of the “window”, formed by titanium atoms, through which the carbon atom diffuses. It is concluded that the x-dependence of the activation energy can be understood by considering that during deformation the diffusion processes of carbon and titanium atoms are coupled.