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Enhanced kinetic stability of vapor-deposited glasses has been established for a variety of glass organic formers. Several recent reports indicate that vapor-deposited glasses can be orientationally anisotropic. In this work, we present results of extensive molecular simulations that mimic a number of features of the experimental vapor deposition process. The simulations are performed on a generic coarse-grained model and an all-atom representation of N,N'-bis(3-methylphenyl)-N,N'- diphenylbenzidine (TPD), a small organic molecule whose vapor-deposited glasses exhibit considerable orientational anisotropy. The coarse-grained model adopted here is found to reproduce several key aspects reported in experiments. In particular, the molecular orientation of vapor-deposited glasses is observed to depend on substrate temperature during deposition. For a fixed deposition rate, the molecular orientation in the glasses changes from isotropic, at the glass transition temperature, Tg, to slightly normal to the substrate at temperatures just below Tg. Well below Tg, molecular orientation becomes predominantly parallel to the substrate. The all-atom model is used to confirm some of the equilibrium structural features of TPD interfaces that arise above the glass transition temperature. We discuss a mechanism based on distinct orientations observed at equilibrium near the surface of the film, which get trapped within the film during the non-equilibrium process of vapor deposition. [ABSTRACT FROM AUTHOR]

We have investigated the properties of vapor-deposited glasses prepared from short polymer chains using molecular dynamics simulations. Vapor-deposited polymer glasses are found to have higher density and higher kinetic stability than ordinary glasses prepared by gradual cooling of the corresponding equilibrium liquid. In contrast to results for binary Lennard-Jones glasses, the deposition rate is found to play an important role in the stability of polymer vapor-deposited glasses. Glasses deposited at the slowest deposition rate and at the optimal substrate temperature are found to correspond to the ordinary glasses that one could hypothetically prepare by cooling the liquid at rates that are 4-5 orders of magnitude slower than those accessible in the current simulations. For intermediate-length polymer chains, the resulting vapor-deposited glasses are found to be highly anisotropic. For short chains, however, the glasses are isotropic, showing that structural anisotropy is not a necessary condition for formation of stable glasses by physical vapor deposition. [ABSTRACT FROM AUTHOR]

A growing body of experimental work indicates that physical vapor deposition provides an effective route for preparation of stable glasses, whose properties correspond in some cases to those expected for glasses that have been aged for thousands of years. In this work, model binary glasses are prepared in a process inspired by physical vapor deposition, in which particles are sequentially added to the free surface of a growing film in molecular dynamics simulations. The resulting glasses are shown to be more stable than those prepared by gradual cooling from the liquid phase. However, it is also shown that the composition of the resulting glass, which is difficult to control in physical vapor deposition simulations of thin films, plays a significant role on the physical characteristics of the material. That composition dependence leads to a re-evaluation of previous results from simulations of thinner films than those considered here, where the equivalent age of the corresponding glasses was overestimated. The simulations presented in this work, which correspond to films that are approximately 38 molecular diameters thick, also enable analysis of the devitrification mechanism by which vapor-deposited glasses transform into the supercooled liquid. Consistent with experiments, it is found that this mechanism consists of a mobility front that propagates from the free interface into the interior of the films. Eliminating surface mobility eliminates this route of transformation into the supercooled liquid. [ABSTRACT FROM AUTHOR]

Following Hausmann et al. (2011), we apply a network approach to measure the level of economic complexity and diversification opportunities of Russian regions. Using Russian and international export data, we find that the complexity of Russian regional economies varies substantially: relatively high in western and central regions, lower in southern and northern Russia and lowest in eastern regions. While Russian regions, on average, have poor diversification opportunities, regions can still diversify their exports by participating in international value-added chains or cooperating in developing group strategies. Our results are highly consistent with two well-established rankings of Russian regional R&D development based on numerous regional indicators, and imply that our network-based measure of complexity captures important features such as the level of regional R&D. [ABSTRACT FROM AUTHOR]

This paper discusses the weakness of average years of schooling as a measure of human capital stock. We consider the example of Russia with its large-scale tertiary education and extensive student employment. Building on Lant Pritchett's observation (Pritchett, L., 2013), we consider insufficient quality of education and relatively low demand for human capital as potential causes of the "earning while learning" expansion. While the latter is likely to reduce the pace of human capital accumulation, it nevertheless may leave average years of schooling untouched. [ABSTRACT FROM AUTHOR]

We present a comparison of Polymer Reference Interaction Site Model (PRISM) theory and molecular dynamics (MD) simulations for studying amphiphilic block copolymers in solution. We use a generic coarse-grained model to represent amphiphilic A-B block copolymers in implicit solvent with the solvophobicity of the B segments captured using effective B-B pairwise attraction modeled using the Lennard-Jones potential. We study the assembly of the amphiphilic A-B block copolymer as a function of solvophobicity for varying copolymer sequences (diblock and triblock) and composition (solvophobic-rich or solvophilic-rich). The PRISM theory equation along with the atomic Percus-Yevick closure is solved to obtain the intermolecular pair correlations in real space, g(r), and structure factors in Fourier space, S(k), for block copolymer solutions at increasing values of solvophobicity. The real-space intermolecular pair correlation functions and structure factors from PRISM theory and from MD simulations are compared directly. We find excellent quantitative agreement in g(r) between PRISM predictions and MD simulations at low solvophobicities where the block copolymer solution is in a disordered state. PRISM theory captures the concentration fluctuations at low solvophobicities well but fails to converge to a numerical solution at higher solvophobicities where we see evolution of ordered structures in MD simulations. Despite this drawback, PRISM theory is a valuable tool as the low solvophobicity results from PRISM predict many of the thermodynamic and structural signatures of the block copolymer solutions at higher solvophobicities. For example, we find that the inverse microphase peak 1/S(k*) at low solvophobicities obtained from PRISM theory, which when extrapolated to zero quantifies the spinodal transition solvophobicity value, is in good quantitative agreement with MD simulations. Additionally, in those systems where MD simulations predict aggregation of the micelles/clusters at high solvophobicity, the structure factors from PRISM theory at low solvophobicity also present an increasing value in the zero-wave vector structure, indicating a tendency toward macrophase separation at higher solvophobicity. These results show the capability of PRISM theory to predict assembly over a wide range of design parameters of copolymers and guide the use of computationally intensive molecular simulations. [ABSTRACT FROM AUTHOR]

This section examines the impact of corruption and bad management on the effectiveness of educational reform and the acquisition of new technologies and human capital in Russia. It describes the quality of the Russian education system and its role in the country's diversification goal. It also explores the negative impact of the over-involvement of the state in the economy and poor property right protections in Russia.

This section examines the negative impact of the presence of weak institutions on the incentives for firms to invest in new technology. It describes the introduction of low-quality institutions into the baseline growth model by assuming that the business owners are required to pay a share of their income to receive a license, permit etc. It also discusses the effect of corruption on the effectiveness of educational reform.

This section describes a baseline growth model which examines how economic agents invest in the acquisition of new technology and accumulate human capital. It explores how a reform of the education system might result in a higher fraction of the human capital endowment actually being invested in education. It also discusses the finding that the presence of weak institutions reduces the incentives for firms to invest in new technology.

The article introduces a paper which examined the impact of corruption and bad management on the effectiveness of educational reform and the acquisition of new technologies and human capital.

In this short paper, we emphasize the importance of reforms sequencing and discuss it in the context of potential educational and institutional reforms in Russia. As weak institutions correspond to a more binding constraint on economic growth than a stagnant education system, we argue that an educational policy is likely to be effective only if it takes place after broader institutional reform is implemented. Otherwise, even a properly implemented education reform might fail to boost economic growth. [ABSTRACT FROM AUTHOR]

An appendix is presented for the paper "Corrupt Bureaucrats, Bad Managers, and the Slow Race Between Education and Technology."

This section discusses the findings of a paper on the impact of corruption and bad management on the effectiveness of educational reform and the acquisition of new technologies and human capital. It describes a developing economy in which a typical firm combines technology and human capital to produce output. It also explores the role of educational reform in the possibility of a brain drain.

We study a developing economy in which the representative firm's production function exhibits complementarities between human capital and the available level of technology. The firm invests in the acquisition of new technology, while employees decide how much human capital to acquire. The rate of human capital accumulation positively affects the economy's growth rate, and therefore in our baseline case a reform that improves the educational system boosts growth. An important caveat, however, is that the absence of robust institutions may lead to lax enforcement of property rights and limit the incentives for firms to invest in new technology. The lack of investment in technology constrains demand for human capital and undermines the success of the education reform. It can even lead to a brain drain as individuals take advantage of the education reform and then move to an economy with higher demand for their acquired skills. We also consider our model findings with respect to the real-world case of Russia. Our main conclusion is that measures to improve the school system need to be accompanied by other institution-building measures that enhance property rights, promote good management practices and reduce incentives to engage in corrupt behaviors. [ABSTRACT FROM AUTHOR]

The impact of ocean deoxygenation on marine ecosystems has recently been recognized as a global problem. The hypoxic layer, a notorious feature of the Black Sea, covers the entire basin at intermediate depths. To understand consequences of the rise of hypoxia in the sea environment, identifying factors that determine the distribution of biological communities at the lower boundary of the oxic zone is important. Continuous measurements of the oxygen profiles throughout the water column and two benthic surveys were conducted in the northeastern Black Sea in 2019–2020. Based on these data and analysis of the oceanographic data archive (1990–2010), two community types that inhabit lower boundaries of the oxic zone were identified: a species-depleted deep-water community (82–117 m) and ephemeral communities in the constant hypoxia zone (128–144 m). Hypoxic event duration was identified as the main environmental factor determining the low diversity of the fauna and benthic community structure in general. The main factor determining the vertical displacement of the multicellular benthos boundary was the duration of the anoxic period. In 2019–2020, this boundary was positioned at a depth of approximately 150 m, which was comparable to the observations from the 1920s and 1930s. • Two community types were found near the oxic zone boundary. • Shift between community types is determined by the proportion of hypoxia. • The multicellular benthos boundary is determined by the proportion of anoxia. • The multicellular benthos boundary position is similar to that in 1920s and 1930s. [ABSTRACT FROM AUTHOR]