Technology frontier, labor productivity and economic growth: Evidence from OECD countries

We use 29 OECD countries data spanning over 1960-2000 to study the growth strategy when countries are close to the technology frontier. Relying on a semi-parametric generalized additive model, we estimate labor productivity equations. We find that the number of agents enrolled in higher education is a determinant of growth. Moreover, when a country is sufficiently near the technology frontier thanks to an increasing R&D expenditure, it becomes optimal to invest in fundamental research, since after a short period of efficiency, business R&D can no longer ensure the transition toward the technology frontier, while higher education presents the opposite shape. These findings support the main assertion of Aghion and Cohen (2004) that countries which are near the technology frontier have to invest in higher education while those far away from the frontier make their technology level growing up by investing in primary and secondary schooling.Education, R&D, Labor Productivity, Economic Growth

Initiation of Olefin Metathesis: Reaction of Deca-2,8-diene with Catalysts formed from Me_4Sn-WC1_6 and Me_3Al_2Cl_3-(Ph_3P)_2(NO)_2Cl_2Mo

The initial product of the metathesis of deca-2,8-diene with metathesis catalysts formed from either Me_4Sn–WCl_6 or Me_3Al_2Cl_3–(Ph_3P)_2(NO)_2Cl_2Mo is propene; labelling of the terminal groups of the diene and the alkylating agents gives a labelling pattern in the propene that is best explained in terms of generation of a carbene in the initiation step from the alkylating agent

Formation of bridged bicycloalkenes via ring closing metathesis

Ring closing metathesis may be used in the formation of small ring bicycloalkenes from monocyclic diene precursors

The role of consumption and the financing of health investment under epidemic shocks

We study the behavior of consumption and health investment resulting from shocks undermining health capital accumulation. We examine the effects on subsequent life cycle of long-lived shocks undermining health with either an acceleration of health capital deterioration, or a decrease in health investment efficiency. We also address the issue of the financing of health investment. We provide new evidence based on nonparametric estimations which show complex non-linear interplay between life expectancy and health expenditure. We then develop a benchmark model where consumption and health capital enter additively in the utility function, featuring independence between the returns from ordinary consumption and health. Then, we depart from this setup by assuming non-additive preferences meaning that ordinary consumption also is crucial for health. We show that a shock undermining health which increases health expenditures and weakens the income base, not only affects savings but also compromises the consumption capacity, the human and physical capital of the economy, and undercuts the process of economic development. We also show that the magnitude of the effects strongly depends on the assumed preferences.consumption, health investments, savings, non-parametric estimation

[4 + 2] Cycloadditions of diphenylketene with a highly substituted 1,3-diene

Diphenylketene (2) undergoes [4 + 2] cycloadditions with the s-cis fixed diene (1) to give the dihydropyran (3) and the cyclohexenone (4)

3-Oxabicyclo[3,2,0]hepta-1,4-diene

3-Oxabicyclo[3,2,0]hepta-1,4-diene (3) has been synthesized by partial hydrogenation of 3-oxabicyclo-[3,2,0]hepta-1,4,6-triene (2)

A closer look at the relationship between life expectancy and economic growth

We first provide a nonparametric inference of the relationship between life expectancy and economic growth on an historical data for 18 countries over the period 1820-2005. The obtained shape shows up convexity for low enough values of life expectancy and concavity for large enough values. We then study this relationship on a benchmark model combining "per- petual youth" and learning-by-investing. In such a benchmark, the generated relationship between life expectancy and economic growth is shown to be strictly increasing and concave. We finally examine a model departing from "perpetual youth" by assuming age-dependent survival probabilities. We show that life-cycle behavior combined with age-dependent sur- vival laws can reproduce our empirical finding.Life expectancy, economic growth, perpetual youth, age-dependent mortality, nonparametric estimation

Reactivity of (1-methoxycarbonylpentadienyl)iron(1+) cations with hydride, methyl, and nitrogen nucleophiles

The reaction of tricarbonyl and (dicarbonyl)triphenylphosphine (1-methoxycarbonyl-pentadientyl)iron(1+) cations 7 and 8 with methyl lithium, NaBH3CN, or potassium phthalimide affords (pentenediyl)iron complexes 9a-c and 11a-b, while reaction with dimethylcuprate, gave (E,Z-diene)iron complexes 10 and 12. Oxidatively induced-reductive elimination of 9a-c gave vinylcyclopropanecarboxylates 17a-c. The optically active vinylcyclopropane (+)-17a, prepared from (1S)-7, undergoes olefin cross-metathesis with excess (+)-18 to yield (+)-19, a C9C16 synthon for the antifungal agent ambruticin. Alternatively reaction of 7 with methanesulfonamide or trimethylsilylazide gave (E,E-diene)iron complexes 14d and e. Huisgen [3 + 2] cyclization of the (azidodienyl)iron complex 14e with alkynes afforded triazoles 25a-e

Possibility of [1,5] sigmatropic shifts in bicyclo[4.2.0]octa-2,4-dienes

The thermal equilibration of the methyl esters of endiandric acids D and E was subject to a computational study. An electrocyclic pathway via an electrocyclic ring opening followed by a ring flip and a subsequent electrocyclization proposed by Nicolaou [Nicolaou, K. C.; Chen, J. S. Chem. Soc. Rev. 2009, 38, 2993], was computationally explored. The free-energy barrier for this electrocyclic route was shown to be very close to the bicyclo[4.2.0]octa-2,4-diene reported by Huisgen [Huisgen, R.; Boche, G.; Dahmen, A.; Hechtl, W. Tetrahedron Lett. 1968, 5215]. Furthermore, the possibility of a [1,5] sigmatropic alkyl group shift of bicyclo[4.2.0]octa-2,4-diene systems at high temperatures was explored in a combined computational and experimental study. Calculated reaction barriers for an open-shell singlet biradical-mediated stepwise [1,5] sigmatropic alkyl group shift were shown to be comparable with the reaction barriers for the bicyclo[4.1.0]hepta-2,4-diene (norcaradiene) walk rearrangement. However, the stepwise sigmatropic pathway is suggested to only be feasible for appropriately substituted compounds. Experiments conducted on a deuterated analogous diol derivative confirmed the calculated (large) differences in barriers between electrocyclic and sigmatropic pathways