Towards energetically viable asymmetric deprotonations : selectivity at more elevated temperatures with C2-symmetric magnesium bisamides

A novel chiral magnesium bisamide has enabled the development of effective asymmetric deprotonation protocols at substantially more elevated temperatures. This new, structurally simple, C2-symmetric magnesium complex displays excellent levels of asymmetric efficiency and energy reduction in the synthesis of enantioenriched enol silane

Ruthenium-catalyzed asymmetric reduction of isoxazolium salts : access to optically active Δ4-isoxazolines

A tethered MsDPEN–ruthenium catalyst reduces a series of isoxazolium salts, affording optically active Δ4-isoxazolines in moderate to good yields and enantioenrichment. The redundancy of heating or high pressures allowed for chemoselective reduction with no subsequent heterocyclic ring opening. Our results reinforce our understanding of the workings of these Noyori-class catalysts

International Negotiations on Climate Change: A Non-cooperative Game Analysis of the Kyoto Protocol

We investigate international negotiations on CO2 emissions reduction in the Kyoto Protocol by non-cooperative multilateral bargaining theory. The negotiation model has two phases, (i) allocating emission reductions to countries and (ii) international emissions trading. Anticipating the competitive equilibrium of emissions trading, each country evaluates an agreement of reduction commitments. We formulate the negotiation process as an n-person sequential bargaining game with random proposers. We show that there exists a unique stationary subgame perfect equilibrium of the bargaining game and that the equilibrium emissions reduction proposed by every country converges to the asymmetric Nash bargaining solution as the probability of negotiation failure by rejection goes to zero. The weights of countries in the asymmetric Nash solution are determined by their probabilities to be selected as proposers. Finally, we present numerical results based on actual emission data on the European Union (EU), the former Soviet Union (FSU), Japan and the United States (USA).asymmetric Nash bargaining solution, CO2 emissions trading, international negotiations, Kyoto Protocol, non-cooperative bargaining games

Compensating for Beamsplitter Asymmetries in Quantum Interference Experiments

The visibility of the quantum interference "dip" seen in the Hong-Ou-Mandel experiment is optimized when a symmetric 50/50 beamsplitter is used in the interferometer. Here we show that the reduction in visibility caused by an asymmetric beamsplitter can be compensated by manipulating the polarization states of the two input photons. We experimentally demonstrate this by using a highly asymmetric 10/90 beamsplitter, and converting an initial dip visibility of 22% to a compensated value of 99%.Comment: 3 pages, 4 figure

Combined effects of a converging beam of light and mirror misalignment in Michelson interferometry

Expressions have been derived and calculations have been made which show that combined effects lead to asymmetric interferograms and reduction in power at zero path difference. Criteria are given for estimating maximum allowable mirror misalignment

A Model of Firm Behaviour with Equity Constraints and Bankruptcy Costs

Based on Greenwald and Stiglitz (1988,1990), this work explores a simple model of microeconomic behaviour which incorporates the impact of capital markets imperfections generated by asymmetric information on firms’ optimal investment decision rules. In particular, this paper analyses how a specific form of asymmetric information problem (adverse selection) may imply lower investment than otherwise through the reduction of the firms’ ability to raise external financing – either in the form of credit rationing or the ‘voluntary’ reduction of firms’ borrowing activity. The natural follow-up to this work would be to formally show how a loan market where both contractual interest rates and loan sizes are (a priori) variable may be characterised by a credit rationing equilibrium.Asymmetric Information, Firm Behaviour, Investment Financing

Oil Price Shocks and Cyclical Dynamics in an Asymmetric Monetary Union

This paper analyzes the dynamic effects of anticipated and unanticipated oil price increases in a small two-country monetary union, which is simultaneously characterized by asymmetric wage adjustments and asymmetric interest rate sensitivities of private absorption. Common external oil price disturbances lead in this asymmetric macroeconomic setup to temporary divergences in output developments across the monetary union. In the case of anticipated oil price increases the relative cyclical position is reversed in the course of the adjustment process. Complete stabilization of the output variables throughout the overall adjustment process requires a restrictive monetary policy being time inconsistent from a quantitative but time consistent from a qualitative point of view. That means that the central bank credibly announces a future reduction in the growth rate of the nominal money stock but actually implements a reduction, which is less restrictive than the original announcement.EMU; international policy transmission; oil price shock; time inconsistency; monetary policy

Setup Cost Reduction and Supply Chain Coordination in Case of Asymmetric Information

Screening contracts are a common approach to solve supply chain coordination problems under asymmetric information. Previous research in this area shows that asymmetric information leads to supply chain coordination deficits. We extend the standard framework of lotsizing decisions under asymmetric information by allowing investments in setup cost reduction. We find that asymmetric information leads to an overinvestment in setup cost reduction. Yet, the overall effect on supply chain performance is ambiguous. We show that these results holds for a wide variety of investment functions.

Minimal Standard Heterotic String Models

Three generation heterotic-string vacua in the free fermionic formulation gave rise to models with solely the MSSM states in the observable Standard Model charged sector. The relation of these models to Z_2 x Z_2 orbifold compactifications dictates that they produce three pairs of untwisted Higgs multiplets. The reduction to one pair relies on the analysis of supersymmetric flat directions, that give superheavy mass to the dispensable Higgs states. We explore the removal of the extra Higgs representations by using the free fermion boundary conditions and hence directly at the string level, rather than in the effective low energy field theory. We present a general mechanism that achieves this reduction by using asymmetric boundary conditions between the left- and right-moving internal fermions. We incorporate this mechanism in explicit string models containing three twisted generations and a single untwisted Higgs doublet pair. We further demonstrate that an additional effect of the asymmetric boundary conditions is to substantially reduce the supersymmetric moduli space.Comment: 20 pages, LaTeX; added reference