Comment on 'Note on the dog-and-rabbit chase problem in introductory kinematics'

We comment on the recent paper by Yuan Qing-Xin and Du Yin-Xiao (Eur. J. Phys. 29 (2008) N43-N45).Comment: 2 pages, no figure

The Impact of Yuan/Ringgit on Bilateral Trade Balance of China and Malaysia

The exposure to exchange rates remains an unresolved issue in international trade literature. The issue is particularly relevant to China and Malaysia, whom relaxed their USD pegging the same day in the mid of 2005. Our paper investigates the exchange rate exposure of China-Malaysian bilateral trade balance over the last 20 years using a standard trade balance equation which is a function of local income, foreign income, and the bilateral real exchange rates of yuan/ringgit. Our modeling is somewhat different with the literature where we take into account the structural breaks of the 1997 Asian currency crisis as well as the fixed-exchange rate regime adopted by the Malaysia. With high frequency monthly sample (Jan1990-Jan2008), we documented GARCH effect in the trade model. Taking that into consideration, our result shows that real exchange rates do play a role in the bilateral trade of China-Malaysia. The long run exchange rate elasticity is consistent with the Marshall-Lerner condition. However, the short run J-curve phenomenon is somewhat inconclusive.Exports, Imports, exchange rates exposure, J-curve, structural breaks, GARCH

Infinite Tension Limit of the Pure Spinor Superstring

Mason and Skinner recently constructed a chiral infinite tension limit of the Ramond-Neveu-Schwarz superstring which was shown to compute the Cachazo-He-Yuan formulae for tree-level d=10 Yang-Mills amplitudes and the NS-NS sector of tree-level d=10 supergravity amplitudes. In this letter, their chiral infinite tension limit is generalized to the pure spinor superstring which computes a d=10 superspace version of the Cachazo-He-Yuan formulae for tree-level d=10 super-Yang-Mills and supergravity amplitudes.Comment: 8 pages, added footnote and reference

2D-Delocalized vs Confined Diradicals

Resumen de la comunicación oral seleccionadaDiradicals are beautiful chemical objects where the more basic and intricate aspects of the chemical bonding are revealed.1 Not this being important enough, nowadays, diradical-based substrates are becoming very appealing for new organic electronic applications. We focus here in conjugated organic diradicals formed by competition between non-aromatic quinoidal structures and their canonical aromatic forms. How this quinoidal(closed-shell)-vs-aromatic(open-shell) energetic balance producing the diradical is affected by several situations has been our objective in the last few years.2 Now, we focusses on how the properties of diradicals are influenced when several diradical canonical forms are available in such a way that create a 2D (i.e., bidimensional) electron delocalization surface in which the diradical substructures are in cross-conjugation mode producing the curious effect of diradical confinement.3 Herein, the diradical molecular properties of compound 1 in Figure 1 will be discussed in connection with 2D delocalization, cross-conjugation and surface confinement. 1. Rajca, A., Chem. Rev., 1994, 94, 871; Abe, M., Chem. Rev. 2013, 113, 7011. 2. Zeng, Z.; X. Shi, L.; Chi, C.; Casado, J.; Wu, J. Chem. Soc. Rev. 2015, 44, 6578. 3. Yuan, D.; Huang, D.; Medina Rivero, S.; Carreras, A.; Zhang, C.; Zou, Y.; Jiao, X.; McNeill, C.R.; Zhu, X.; Di, C.; Zhu, D.; Casanova, D.; Casado, J. CHEM, 2019, accepted.Universidad de Málaga. Campus de Excelencia Internacional Andalucía Tech

Does China Still Have a Labor Cost Advantage?

In recent years wages in China have been rising and the yuan has appreciated, potentially eroding China’s cost advantage in manufactures. This paper explores the evolution of China’s relative unit labor costs in manufacturing over 1998-2009. Between 1998 and 2003 China’s unit labor costs fell, but since 2003 they have increased both absolutely and relative to US unit labor costs. Much of the rise in China’s relative unit labor costs can be traced to a real appreciation of the yuan against the dollar. Despite the recent rise, China’s unit labor costs remain low relative to those in most other countries.China, labor costs, productivity, international competitiveness, real exchange rate

DJpsiFDC: an event generator for the process gg→J/ψJ/ψgg\to J/\psi J/\psi at LHC

DJpsiFDC is an event generator package for the process $gg\to J/\psi J/\psi$. It generates events for primary leading-order $2\to 2$ processes. The package could generate a LHE document and this document could easily be embedded into detector simulation software frameworks. The package is produced in Fortran codes.Comment: 10 pages, 3 figure

China and its Dollar Exchange Rate: A Worldwide Stabilizing Influence?

We argue that criticism concerning the Chinese dollar peg is misplaced as no predictable link exists between the exchange rate and the trade balance of an international creditor economy. The stable nominal yuan/dollar rate is argued to have stabilized Chinese, East Asian and global growth. However, linked to US low interest rates, Chinese sterilization policies and potentially subsidized capital allocation in China the real yuan/dollar rate is undervalued. This has caused—both in China and the United States— structural distortions and threatens to undermine global growth and stability. We propose Sino-American policy coordination to escape from the policy dilemma, which continues to drive global imbalances.China, exchange rate, financial stability, economic stability, international policy coordination, currency war