Calculability of Quark Mixing Parameters from General Nearest Neighbor Interaction Texture Quark Mass Matrices

We perform an analysis of general quark mass matrices in the general nearest neighbor interaction form. Excellent agreement with experiment is realized with this general texture, which is neither hermitian nor real-symmetric. We then propose a new class of quark mass matrices that contain no additional parameters other than the quark masses themselves, and thus possess calculability, i.e., ensure a relationship between the six quark masses and four flavor-mixing parameters of the Standard Model.Comment: 11 pages. To be published in Physics Letters

Woodford goes to Africa

This paper analyses the effects of inflation shocks, demands shocks, and aid shocks on low-income, quasi-emerging-market economies, and discusses how monetary policy can be used to manage these effects. We make use of a model developed for such economies by Adam et al. (2007). We examine the e¤ects of four things which this model features, which we take to be typical of such economies. These are: the existence of a tradeables/non-tradeables production structure, the fact that international capital movements are - at least initially - confined to the effects of currency substitution by domestic residents, the use of targets for financial assets in the implementation of monetary policy, and the pursuit, in some countries, of a fixed exchange rate. We then modify the model to examine the effect on such economies of three major changes, changes which we take to be part of the transition by such economies towards more fully- fledged emerging-market status: an opening of the capital account so that uncovered- interest-parity comes to hold, a move to floating exchange rates, and the replacement of fixed stocks of financial aggregates by the pursuit of a Taylor rule in the conduct of monetary policy.currency substitution, emerging market macroeconomics, interactions between fiscal and monetary policy, Taylor rule

Defective development of gamma/delta T cells in interleukin 7 receptor-deficient mice is due to impaired expression of T cell receptor gamma genes.

Mice lacking the interleukin 7 receptor (IL-7R) generate alpha/beta T cells at a detectable but greatly reduced rate, but gamma/delta T cells are completely absent. The special role of IL-7R signaling in gamma/delta T cell development has remained unclear. IL-7Ralpha(-/-) mice exhibit a paucity of gamma gene rearrangements. This striking observation can be explained by a defect in T cell receptor (TCR)-gamma gene rearrangement, a defect in TCR-gamma gene transcription leading to death of gamma/delta lineage cells, and/or a requirement for IL-7R in commitment of cells to the gamma/delta lineage. To determine the role of IL-7R signaling in gamma/delta T cell development, we examined transcription of a prerearranged TCR-gamma transgene in IL-7Ralpha(-/-) mice, as well as the effects of IL-7 on transcription of endogenous, rearranged TCR-gamma genes in alpha/beta lineage cells. The results demonstrate that IL-7R-mediated signals are necessary for the normal expression of rearranged TCR-gamma genes. Equally significant, the results show that the poor expression of TCR-gamma genes in IL-7Ralpha(-/-) mice is responsible for the selective deficit in gamma/delta cells in these mice, since a high copy TCR-gamma transgene exhibited sufficient residual expression in IL-7Ralpha(-/-) mice to drive gamma/delta cell development. The results indicate that the absence of gamma/delta T cells in IL-7Ralpha(-/-) mice is due to insufficient TCR-gamma gene expression

On the validity and breakdown of the Onsager symmetry in mesoscopic conductors interacting with environments

We investigate magnetic-field asymmetries in the linear transport of a mesoscopic conductor interacting with its environment. Interestingly, we find that the interaction between the two systems causes an asymmetry only when the environment is out of equilibrium. We elucidate our general result with the help of a quantum dot capacitively coupled to a quantum Hall conductor and discuss the asymmetry dependence on the environment bias and induced dephasing.Comment: 4 pages, 4 figures; discussions clarified; published versio