Probing the Structure and Energetics of Dislocation Cores in SiGe Alloys through Monte Carlo Simulations

We present a methodology for the investigation of dislocation energetics in segregated alloys based on Monte Carlo simulations which equilibrate the topology and composition of the dislocation core and its surroundings. An environment-dependent partitioning of the system total energy into atomic contributions allows us to link the atomistic picture to continuum elasticity theory. The method is applied to extract core energies and radii of 60 degrees glide dislocations in segregated SiGe alloys which are inaccessible by other methods.Comment: 5 pages, to be published in Physical Review Letter

Medium term effects of culture, transactions and institutions on opportunity entrepreneurship

Cultural evolution is a long-term endogenous process which is revealed in society's cultural traits and it is embodied in institutional characteristics (property rights protection, rule of law, etc.) and transaction characteristics (risk levels, time required for start-ups, corruption levels, literacy levels, etc.). In the short- and medium-term, culture, institutions and transactions are exogenous for the economic and societal system. The paper aims to explore the roles of cultural, transaction and institution characteristics in the determination of opportunity entrepreneurship, at the medium-term. A series of variables is used to express these roles, which are analysed with a principal component analysis and a regression analysis. As expected, the conclusions confirm that the cultural traits both positively and negatively affect opportunity entrepreneurship depending on the particular traits combination. Moreover, the effect of enhanced transaction characteristics and economic institutions is conducive to opportunity entrepreneurship. Performing a sensitivity analysis, we construct a hypothetical, more opportunity entrepreneurship-oriented world by postulating pro-entrepreneurship cultural traits. In this "new world", because cultural traits are no longer an issue, they present "entrepreneurial maturity"; the important factors in promoting opportunity entrepreneurship are transaction and economic institution characteristics

Carvedilol in hypertension treatment

Although β-blockers have been previously shown to effectively reduce blood pressure (BP) and have been used for hypertension treatment for over 40 years, their effect on cardiovascular morbidity and mortality in hypertensive patients remains controversial and its use in uncomplicated hypertension is currently under debate. However, data on the above field derive mainly from studies which were conducted with older agents, such as atenolol and metoprolol, while considerable pharamacokinetic and pharmacodynamic heterogeneity is present within the class of β-blockers. Carvedilol, a vasodilating non-cardioselective β-blocker, is a compound that seems to give the opportunity to the clinician to use a cardioprotective agent without the concerning hemodynamic and metabolic actions of traditional β-blocker therapy. In contrast with conventional β-blockers, carvedilol maintains cardiac output, has a less extended effect on heart rate and reduces BP by decreasing vascular resistance. Further, several studies has shown that carvedilol has a beneficial or at least neutral effect on metabolic parameters, such as glycemic control, insulin sensitivity, and lipid metabolism, suggesting that they could be used in subjects with the metabolic syndrome or diabetes without negative consequences. This article summarizes the distinct pharmacologic, hemodynamic, and metabolic properties of carvedilol in relation to conventional β-blockers, attempting to examine the potential use of this agent for hypertension treatment

Cosmology from an AdS Schwarzschild black hole via holography

We derive the equations of cosmological evolution from an AdS Schwarzschild black hole via holographic renormalization with appropriate boundary conditions.Comment: 6 page

Softening of ultra-nanocrystalline diamond at low grain sizes

Ultra-nanocrystalline diamond is a polycrystalline material, having crystalline diamond grains of sizes in the nanometer regime. We study the structure and mechanical properties of this material as a function of the average grain size, employing atomistic simulations. From the calculated elastic constants and the estimated hardness, we observe softening of the material as the size of its grains decreases. We attribute the observed softening to the enhanced fraction of interfacial atoms as the average grain size becomes smaller. We provide a fitting formula for the scaling of the cohesive energy and bulk modulus with respect to the average grain size. We find that they both scale as quadratic polynomials of the inverse grain size. Our formulae yield correct values for bulk diamond in the limit of large grain sizes.Comment: 5 pages, 3 figures, to be published in Acta Materiali

Why Coevolution of Culture and Institutions Matters for Economic Development and Growth?

Theoretical considerations that choose to make reference to the institutional and cultural considerations presuppose that these are in an optimal form. However, this is not the case in the real world. This chapter argues that the coevolution requirements of institutional and culture change are critical for economic outcomes. When institutions and culture coevolve in an optimal pattern, economic development and growth are facilitated. In contrast, when institutions and culture deviate from the optimal pace of coevolution, incompatible alterations of institutions and culture may end up causing an inability of the policy designers to implement the required changes in institutions and/or cultural behaviors. The result can be a series of failing attempts to implement a modernized progrowth framework of institutional settings and cultural behaviors. Using a dataset of 80 countries for the period 1981–2019, the analysis concludes that institutions and culture are complements—and not substitutes—in terms of their role in economic development, as when both sizes are strong it leads to higher levels of GDP per capita. When either or both of them are at a weak level, economic development is much lower