The monetary instrument matters

This paper revisits the debate over the money supply versus the interest rate as the instrument of monetary policy. Using a dynamic stochastic general equilibrium framework, the authors examine the effects of alternative monetary policy rules on inflation persistence, the information content of monetary data, and real variables. They show that inflation persistence and the variability of inflation relative to money growth depend on whether the central bank follows a money growth rule or an interest rate rule. With a money growth rule, inflation is not persistent and the price level is much more volatile than the money supply. Those counterfactual implications are eliminated by the use of interest rate rules whether prices are sticky or not. A central bank's use of interest rate rules, however, obscures the information content of monetary aggregates and also leads to subtle problems for econometricians trying to estimate money demand functions or to identify shocks to the trend and cycle components of the money stock.Monetary policy ; Money supply ; Interest rates

Taylor-type rules and total factor productivity

This paper examines the impact of a persistent shock to the growth rate of total factor productivity in a New Keynesian model in which the central bank does not observe the shock. The authors then investigate the performance of alternative policy rules in such an incomplete information environment. While some rules perform better than others, the authors demonstrate that inflation is more stable after a persistent productivity shock when monetary policy targets the output growth rate (not the output gap) or the price-level path (not the inflation rate). Both the output growth and price-level path rules generate less volatility in output and inflation following a persistent productivity shock compared with the Taylor rule.Taylor's rule ; Productivity ; Industrial productivity

Inflation risk and optimal monetary policy

This paper shows that the optimal monetary policies recommended by New Keynesian models still imply a large amount of inflation risk. We calculate the term structure of inflation uncertainty in New Keynesian models when the monetary authority adopts the optimal policy. When the monetary policy rules are modified to include some weight on a price path, the economy achieves equilibria with substantially lower long-run inflation risk. With either sticky prices or sticky wages, a price path target reduces the variance of inflation by an order of magnitude more than it increases the variability of the output gap.Monetary policy ; Inflation (Finance)

Exosome-mediated Transfer of αvβ3 Integrin from Tumorigenic to Nontumorigenic Cells Promotes a Migratory Phenotype.

The αvβ3 integrin is known to be highly upregulated during cancer progression and promotes a migratory and metastatic phenotype in many types of tumors. We hypothesized that the αvβ3 integrin is transferred through exosomes and, upon transfer, has the ability to support functional aberrations in recipient cells. Here, for the first time, it is demonstrated that αvβ3 is present in exosomes released from metastatic PC3 and CWR22Pc prostate cancer cells. Exosomal β3 is transferred as a protein from donor to nontumorigenic and tumorigenic cells as β3 protein or mRNA levels remain unaffected upon transcription or translation inhibition in recipient cells. Furthermore, it is shown that upon exosome uptake, de novo expression of an αvβ3 increases adhesion and migration of recipient cells on an αvβ3 ligand, vitronectin. To evaluate the relevance of these findings, exosomes were purified from the blood of TRAMP mice carrying tumors where the expression of αvβ3 is found higher than in exosomes from wild-type mice. In addition, it is demonstrated that αvβ3 is coexpressed with synaptophysin, a biomarker for aggressive neuroendocrine prostate cancer. IMPLICATIONS: Overall this study reveals that the αvβ3 integrin is transferred from tumorigenic to nontumorigenic cells via exosomes, and its de novo expression in recipient cells promotes cell migration on its ligand. The increased expression of αvβ3 in exosomes from mice bearing tumors points to its clinical relevance and potential use as a biomarker. Mol Cancer Res; 14(11); 1136-46. ©2016 AACR

Microrheology with optical tweezers: data analysis

We present a data analysis procedure that provides the solution to a long-standing issue in microrheology studies, i.e. the evaluation of the fluids' linear viscoelastic properties from the analysis of a finite set of experimental data, describing (for instance) the time-dependent mean-square displacement of suspended probe particles experiencing Brownian fluctuations. We report, for the first time in the literature, the linear viscoelastic response of an optically trapped bead suspended in a Newtonian fluid, over the entire range of experimentally accessible frequencies. The general validity of the proposed method makes it transferable to the majority of microrheology and rheology techniques

KIC 10080943: a binary star with two γ Doradus/δ Scuti hybrid pulsators. Analysis of the g modes

We use 4 yr of Kepler photometry to study the non-eclipsing spectroscopic binary KIC 10080943. We find both components to be γ Doradus/δ Scuti hybrids, which pulsate in both p and g modes. We present an analysis of the g modes, which is complicated by the fact that the two sets of l = 1 modes partially overlap in the frequency spectrum. Nevertheless, it is possible to disentangle them by identifying rotationally split doublets from one component and triplets from the other. The identification is helped by the presence of additive combina- tion frequencies in the spectrum that involve the doublets but not the triplets. The rotational splittings of the multiplets imply core rotation periods of about 11 and 7 d in the two stars. One of the stars also shows evidence of l = 2 modes

Geometric Aspects of the Moduli Space of Riemann Surfaces

This is a survey of our recent results on the geometry of moduli spaces and Teichmuller spaces of Riemann surfaces appeared in math.DG/0403068 and math.DG/0409220. We introduce new metrics on the moduli and the Teichmuller spaces of Riemann surfaces with very good properties, study their curvatures and boundary behaviors in great detail. Based on the careful analysis of these new metrics, we have a good understanding of the Kahler-Einstein metric from which we prove that the logarithmic cotangent bundle of the moduli space is stable. Another corolary is a proof of the equivalences of all of the known classical complete metrics to the new metrics, in particular Yau's conjectures in the early 80s on the equivalences of the Kahler-Einstein metric to the Teichmuller and the Bergman metric.Comment: Survey article of our recent results on the subject. Typoes corrrecte

Topology of amorphous tetrahedral semiconductors on intermediate lengthscales

Using the recently-proposed ``activation-relaxation technique'' for optimizing complex structures, we develop a structural model appropriate to a-GaAs which is almost free of odd-membered rings, i.e., wrong bonds, and possesses an almost perfect coordination of four. The model is found to be superior to structures obtained from much more computer-intensive tight-binding or quantum molecular-dynamics simulations. For the elemental system a-Si, where wrong bonds do not exist, the cost in elastic energy for removing odd-membered rings is such that the traditional continuous-random network is appropriate. Our study thus provides, for the first time, direct information on the nature of intermediate-range topology in amorphous tetrahedral semiconductors.Comment: 4 pages, Latex and 2 postscript figure