Infrared activity of hydrogen molecules trapped in Si

The rovibrational-translational states of a hydrogen molecule moving in a cage site in Si, when subjected to an electrical field arising from its surroundings, are investigated. The wave functions are expressed in terms of basis functions consisting of the eigenfunctions of the molecule confined to move in the cavity and rovibrational states of the free molecule. The energy levels, intensities of infrared and Raman transitions, effects of uniaxial stress, and a neighboring oxygen defect are found and compared with existing experimental data

Global, regional, and national age-sex-specific mortality and life expectancy, 1950–2017: a systematic analysis for the Global Burden of Disease Study 2017

BACKGROUND: Assessments of age-specific mortality and life expectancy have been done by the UN Population Division, Department of Economics and Social Affairs (UNPOP), the United States Census Bureau, WHO, and as part of previous iterations of the Global Burden of Diseases, Injuries, and Risk Factors Study (GBD). Previous iterations of the GBD used population estimates from UNPOP, which were not derived in a way that was internally consistent with the estimates of the numbers of deaths in the GBD. The present iteration of the GBD, GBD 2017, improves on previous assessments and provides timely estimates of the mortality experience of populations globally. METHODS: The GBD uses all available data to produce estimates of mortality rates between 1950 and 2017 for 23 age groups, both sexes, and 918 locations, including 195 countries and territories and subnational locations for 16 countries. Data used include vital registration systems, sample registration systems, household surveys (complete birth histories, summary birth histories, sibling histories), censuses (summary birth histories, household deaths), and Demographic Surveillance Sites. In total, this analysis used 8259 data sources. Estimates of the probability of death between birth and the age of 5 years and between ages 15 and 60 years are generated and then input into a model life table system to produce complete life tables for all locations and years. Fatal discontinuities and mortality due to HIV/AIDS are analysed separately and then incorporated into the estimation. We analyse the relationship between age-specific mortality and development status using the Socio-demographic Index, a composite measure based on fertility under the age of 25 years, education, and income. There are four main methodological improvements in GBD 2017 compared with GBD 2016: 622 additional data sources have been incorporated; new estimates of population, generated by the GBD study, are used; statistical methods used in different components of the analysis have been further standardised and improved; and the analysis has been extended backwards in time by two decades to start in 1950. FINDINGS: Globally, 18·7% (95% uncertainty interval 18·4–19·0) of deaths were registered in 1950 and that proportion has been steadily increasing since, with 58·8% (58·2–59·3) of all deaths being registered in 2015. At the global level, between 1950 and 2017, life expectancy increased from 48·1 years (46·5–49·6) to 70·5 years (70·1–70·8) for men and from 52·9 years (51·7–54·0) to 75·6 years (75·3–75·9) for women. Despite this overall progress, there remains substantial variation in life expectancy at birth in 2017, which ranges from 49·1 years (46·5–51·7) for men in the Central African Republic to 87·6 years (86·9–88·1) among women in Singapore. The greatest progress across age groups was for children younger than 5 years; under-5 mortality dropped from 216·0 deaths (196·3–238·1) per 1000 livebirths in 1950 to 38·9 deaths (35·6–42·83) per 1000 livebirths in 2017, with huge reductions across countries. Nevertheless, there were still 5·4 million (5·2–5·6) deaths among children younger than 5 years in the world in 2017. Progress has been less pronounced and more variable for adults, especially for adult males, who had stagnant or increasing mortality rates in several countries. The gap between male and female life expectancy between 1950 and 2017, while relatively stable at the global level, shows distinctive patterns across super-regions and has consistently been the largest in central Europe, eastern Europe, and central Asia, and smallest in south Asia. Performance was also variable across countries and time in observed mortality rates compared with those expected on the basis of development. INTERPRETATION: This analysis of age-sex-specific mortality shows that there are remarkably complex patterns in population mortality across countries. The findings of this study highlight global successes, such as the large decline in under-5 mortality, which reflects significant local, national, and global commitment and investment over several decades. However, they also bring attention to mortality patterns that are a cause for concern, particularly among adult men and, to a lesser extent, women, whose mortality rates have stagnated in many countries over the time period of this study, and in some cases are increasing

Unemployment and Growth in the Long Run: An Efficiency-Wage Model with Optimal Savings

This paper develops an efficiency-wage model of steady-state equilibrium with labor-augmenting technical progress, and uses the model to explore the long-run relationship between unemployment and growth. The rate of productivity growth is either specified exogenously or determined endogenously (from learning by doing). In both cases, we preserve key results of the Shapiro-Stiglitz efficiency-wage analysis without growth. Our model, however, also yields some striking new results. For inStance, an exogenous increase in the growth rate may raise the rate of efficiency-wage unemployment, and a once-for-a1l rise in the labor force may reduce the unemployment rate in the endogenous-growth case.economic growth, unemployment, efficiency wage.economic growth, unemployment, efficiency wage

A dynamic model of shirking and unemployment: Private saving, public debt, and optimal taxation

This paper introduces private saving and public debt into the shirking-unemployment model of Shapiro and Stiglitz (1984), while relaxing their exclusive focus on steady states. After generalizing their no-shirking constraint to accommodate asset accumulation, and demonstrating that the resulting economy's equilibrium is saddle-path stable, we use our dynamic model to obtain significant departures from the Shapiro-Stiglitz prescriptions for optimal policy. Most notably, wage income should be taxed (not subsidized) in the long run if the labor market is sufficiently distorted. Furthermore, interest income should be (exhaustively) taxed only during an initial interval of time, as in Chamley's (1986) full-employment model

Unemployment and growth in the long run: An efficiency-wage model with optimal savings

An efficiency-wage model of steady-state equilibrium with labor-augmenting technical progress is developed to explore the long-run relationship between unemployment and growth. The rate of productivity growth is either specified exogenously or determined endogenously. In both cases, we preserve key results of the Shapiro-Stiglitz efficiency-wage analysis without growth. Our model, however, also yields some striking new results. For instance, an exogenous increase in the growth rate may raise the rate of efficiency-wage unemployment, and a once-for-all rise in the labor force may reduce the unemployment rate in the endogenous-growth case

Absolute and comparative advantage, reconsidered: The pattern of international trade with optimal saving

The paper obtains new results about absolute and comparative advantage, by introducing international technological differences into the three-sector Findlay-Komiya and two-sector Oniki-Uzawa-Stiglitz models of open-economy growth with optimal saving. For example, if a country has the same Hicks-neutral advantage in all industries, it exports the capital-intensive tradable, even though the technological advantage is only absolute rather than comparative. Alternatively, even a small comparative advantage in some good is sufficient for the advanced country to export this product, regardless of relative factor supplies. In either case, the fundamental reason for trade is technological superiority rather than factor abundance

Dynamic stability in a two-country model of optimal growth and international trade

Despite an extensive literature on dynamic stability in optimal-growth models of closed economies, analogous work on internationally trading economies is scarce, focusing only on the special case of a 'small' open economy. To address this scarcity, the present paper establishes saddle-path stability of equilibrium in an infinite-horizon continuous-time model of two (large) countries that grow optimally and trade freely. The model has three products (including a non-traded capital good) and an exogenously fixed rate of growth. We also discuss briefly the dynamic-stability implications of modifying the model to have only two goods or an endogenous growth rate

The Diterpene Glycoside, Rebaudioside A, Does not Improve Glycemic Control or Affect Blood Pressure After Eight Weeks Treatment in the Goto-Kakizaki Rat

The plant, Stevia rebaudiana Bertoni (SrB), has been used for the treatment of diabetes in traditional medicine. Previously, we have demonstrated that long-term administration of the glycoside stevioside has insulinotropic, glucagonostatic, anti-hyperglycemic and blood pressure-lowering effects in type 2 diabetic animal models. The aim of this study was to elucidate if long-term administration of rebaudioside A, another glycoside isolated from the plant SrB, could improve glycemic control and lower blood pressure in an animal model of type 2 diabetes. We divided male Goto-Kakizaki (GK) rats into two groups which were fed a standard laboratory chow diet for eight weeks. The diet was supplemented with oral rebaudioside A (0.025 g/kg BW/day) in the experimental group. Blood glucose, weight, blood pressure and food intake were measured weekly. Animals were equipped with an intra-arterial catheter, and at week eight the conscious rats underwent an intra-arterial glucose tolerance test (IAGTT) (2.0 g/kg BW). During the IAGTT, the level of glucose, glucagon, and insulin responses did not differ significantly between the two groups. Fasting levels of glucose, glucagon, insulin or levels of blood lipids did not differ between the groups throughout the study period. We observed no effect on blood pressure or weight development. In conclusion, oral supplementation with rebaudioside A (0.025 g/kg BW/day) for eight weeks did not influence blood pressure or glycemic control in GK rats. Rebaudioside A failed to show the beneficial effects in diabetic animals previously demonstrated for stevioside