Electroweak nuclear response in quasi-elastic regime

The availability of the double-differential charged-current neutrino cross section, measured by the MiniBooNE collaboration using a carbon target, allows for a systematic comparison of nuclear effects in quasi-elastic electron and neutrino scattering. The results of our study, based on the impulse approximation scheme and a state-of-the-art model of the nuclear spectral functions, suggest that the electron cross section and the flux averaged neutrino cross sections, corresponding to the same target and comparable kinematical conditions, cannot be described within the same theoretical approach using the value of the nucleon axial mass obtained from deuterium measurements. We analyze the assumptions underlying the treatment of electron scattering data, and argue that the description of neutrino data will require a new {\em paradigm}, suitable for application to processes in which the lepton kinematics is not fully determined

Conference Summary: Price Adjustment and Monetary Policy

The 2002 Bank of Canada Conference focused on price adjustment, a critically important issue for monetary policy. Given the acceptance throughout the 1990s and 2000s of the existence of price stickiness in goods or labour markets, or both, and of the important role that monetary policy can play in an economy, the time was right for a conference that would focus on current developments in this area of research, particularly within a Canadian context. Conference papers covering both theoretical and empirical studies explored such themes as sources of the persistence of inflation, forward-looking models of inflation, models of inflation in open economies, the macroeconomic effects of technology shocks, and models of the interaction between wages, prices, and real economic outcomes.

Of faeces and sweat. How much a mouse is willing to run: having a hard time measuring spontaneous physical activity in different mouse sub-strains

Physical activity has multiple beneficial effects in the physiology and pathology of the organism. In particular, we and other groups have shown that running counteracts cancer cachexia in both humans and rodents. The latter are prone to exercise in wheel-equipped cages even at advanced stages of cachexia. However, when we wanted to replicate the experimental model routinely used at the University of Rome in a different laboratory (i.e. at Paris 6 University), we had to struggle with puzzling results due to unpredicted mouse behavior. Here we report the experience and offer the explanation underlying these apparently irreproducible results. The original data are currently used for teaching purposes in undergraduate student classes of biological sciences

Invariance under quasi-isometries of subcritical and supercritical behaviour in the Boolean model of percolation

In this work we study the Poisson Boolean model of percolation in locally compact Polish metric spaces and we prove the invariance of subcritical and supercritical phases under mm-quasi-isometries. In other words, we prove that if the Poisson Boolean model of percolation is subcritical or supercritical (or exhibits phase transition) in a metric space M which is mm-quasi-isometric to a metric space N, then these phases also exist for the Poisson Boolean model of percolation in N. Then we apply these results to understand the phenomenon of phase transition in a large family of metric spaces. Indeed, we study the Poisson Boolean model of percolation in the context of Riemannian manifolds, in a large family of nilpotent Lie groups and in Cayley graphs. Also, we prove the existence of a subcritical phase in Gromov spaces with bounded growth at some scale

A dual Stage ion engine for high impulse missions

In this paper, the applicability of dual stage ion opticsand in particular of the so-called dual stage ion engine to highpower, high specific impulse missions will be evaluated. First, theperformance limits of conventional two gridded ion engines (GIE)will be discussed and the advantages provided by dual stage ionengines reported. The limits of applicability of a dual stage ionengine will be analyzed analytically and the results confirmednumerically. The lifetime and performance of a three griddeddual stage ion engine (DS3G) will be numerically investigated andcompared to those of a conventional GIE assessing for the firsttime in the open literature under what condition dual stage ionoptics provide performance improvements over conventional GIEsand what is its impact on the thruster lifetime. Dual stage ionengines have been found to be capable of providing higher thrustdensity and longer lifetime with respect to conventional griddedion engines

Another Look at the Inflation-Target Horizon

The conduct of monetary policy within an inflation-targeting framework requires the establishment of an inflation-target horizon, which is the average time it takes inflation to return to the target. Policy-makers have an interest in communicating this horizon, since it is likely to help anchor inflation expectations. This article focuses on the determination of the appropriate policy horizon by reporting on two recent Bank of Canada studies. The evidence suggests that the current target horizon of six to eight quarters remains appropriate. It is important to note that the duration of the optimal inflation-target horizon varies widely, depending on the combination of shocks to the economy. In rare cases when the financial accelerator is triggered by a persistent shock, such as an asset-price bubble, it may be appropriate to take a longer view of the inflation-target horizon.

Next Steps for Canadian Monetary Policy

In 2006, the Bank initiated a research program exploring two alternatives to the current inflation-targeting framework: (i) lowering the inflation target and (ii) shifting to a price-level target. This article discusses progress to date, places the Bank's findings in the context of a broader literature, and identifies avenues for future research. Earlier literature and recent studies at the Bank suggest that an inflation target below two per cent is likely preferable to the status quo, though it is unclear how much lower policy-makers should aim and also how much Canadians would benefit from a shift. With regard to the price-level target, evidence is more mixed, with need for study concerning (i) the target's influence on contracting behaviour and inflation expectations; (ii) strategies for ensuring credibility in the commitment to price-level targeting; and (iii) the Canadian economy's vulnerability to shocks that the literature identifies as particularly detrimental to the target's performance.