Is money useful in the conduct of monetary policy?

Monetary policy ; Money supply

Three-dimensional foam flow resolved by fast X-ray tomographic microscopy

Thanks to ultra fast and high resolution X-ray tomography, we managed to capture the evolution of the local structure of the bubble network of a 3D foam flowing around a sphere. As for the 2D foam flow around a circular obstacle, we observed an axisymmetric velocity field with a recirculation zone, and indications of a negative wake downstream the obstacle. The bubble deformations, quantified by a shape tensor, are smaller than in 2D, due to a purely 3D feature: the azimuthal bubble shape variation. Moreover, we were able to detect plastic rearrangements, characterized by the neighbor-swapping of four bubbles. Their spatial structure suggest that rearrangements are triggered when films faces get smaller than a characteristic area.Comment: 5 pages, 5 figure

Fetal Transplant-Induced Restoration of Spatial Memory in Rats with Lesions of the Nucleus Basalis of Meynert

Bilateral lesions of the nucleus basalis of Meynert (nbM) in rats produced mnemonic deficits when subjects were tested on tests of spatial memory over a period of 3 to 7.5 months postoperatively. The transplantation of cholinergic- rich, fetal ventral forebrain tissue to either two or four frontoparietal cortical sites normalized performance on the spatial memory tasks. However, which transplant condition yielded recovery depended upon the nature of the task and/or posttransplantation interval. When assessed 8 months following transplant surgery, cortical choline acetyltransferase and acetylcholinesterase activity levels in both transplant groups were comparable to those values found in sham-operated animals. These data indicate that fetal transplants can reverse the mnemonic deficits and restore cortical cholinergic neurochemical activity to near-normal levels in rats with nbM lesions

A Step Into the Definition of the Seismic Risk for the City of Benevento (Italy)

This paper gives a contribution in the definition of the seismic hazard for the city of Benevento in Southern Italy, from a geotechnical engineering viewpoint. To pursue this goal, an extensive geotechnical characterization of the city subsoil was achieved collecting data available at the Department of Geotechnical Engineering, University of Napoli and Benevento municipal technical office. Attention was paid in defining strain dependent shear stiffness and damping ratio for the geomaterials present in the urban area. A new method to correct the Masing criteria was adopted. Numerical analyses were performed considering the subsoil as a continuous one-phase equivalent linear medium. The 1-D analyses were carried out using Shake-like codes. The seismic hazard in the city was evaluated on the basis of two seismic scenarios, respectively characterized by low and high acceleration levels. The final result of the work is a seismic zonation of the city of Benevento. It was found that zonation maps are largely dependent from the chosen seismic scenario

A Step Into the Definition of the Seismic Risk for the City of Benevento (Italy)

This paper gives a contribution in the definition of the seismic hazard for the city of Benevento in Southern Italy, from a geotechnical engineering viewpoint. To pursue this goal, an extensive geotechnical characterization of the city subsoil was achieved collecting data available at the Department of Geotechnical Engineering, University of Napoli and Benevento municipal technical office. Attention was paid in defining strain dependent shear stiffness and damping ratio for the geomaterials present in the urban area. A new method to correct the Masing criteria was adopted. Numerical analyses were performed considering the subsoil as a continuous one-phase equivalent linear medium. The 1-D analyses were carried out using Shake-like codes. The seismic hazard in the city was evaluated on the basis of two seismic scenarios, respectively characterized by low and high acceleration levels. The final result of the work is a seismic zonation of the city of Benevento. It was found that zonation maps are largely dependent from the chosen seismic scenario

Chronography of the Milky Way's Halo System with Field Blue Horizontal-Branch Stars

In a pioneering effort, Preston et al. reported that the colors of blue horizontal-branch (BHB) stars in the halo of the Galaxy shift with distance, from regions near the Galactic center to about 12 kpc away, and interpreted this as a correlated variation in the ages of halo stars, from older to younger, spanning a range of a few Gyrs. We have applied this approach to a sample of some 4700 spectroscopically confirmed BHB stars selected from the Sloan Digital Sky Survey to produce the first "chronographic map" of the halo of the Galaxy. We demonstrate that the mean de-reddened g$-$r color, , increases outward in the Galaxy from $-$0.22 to $-$0.08 (over a color window spanning [$-$0.3:0.0]) from regions close to the Galactic center to ~40 kpc, independent of the metallicity of the stars. Models of the expected shift in the color of the field BHB stars based on modern stellar evolutionary codes confirm that this color gradient can be associated with an age difference of roughly 2-2.5 Gyrs, with the oldest stars concentrated in the central ~15 kpc of the Galaxy. Within this central region, the age difference spans a mean color range of about 0.05 mag (~0.8 Gyrs). Furthermore, we show that chronographic maps can be used to identify individual substructures, such as the Sagittarius Stream, and overdensities in the direction of Virgo and Monoceros, based on the observed contrast in their mean BHB colors with respect to the foreground/background field population.Comment: 6 pages, 4 figures, ApJ letter

A Modern Ethernet Data Acquisition Architecture for Fermilab Beam Instrumentation

The Fermilab Accelerator Division, Instrumentation Department is adopting an open-source framework to replace our embedded VME-based data acquisition systems. Utilizing an iterative methodology, we first moved to embedded Linux, removing the need for VxWorks. Next, we adopted Ethernet on each data acquisition module eliminating the need for the VME backplane in addition to communicating with a rack mount server. Development of DDCP (Distributed Data Communications Protocol), allowed for an abstraction between the firmware and software layers. Each data acquisition module was adapted to read out using 1 GbE and aggregated at a switch which up linked to a 10 GbE network. Current development includes scaling the system to aggregate more modules, to increase bandwidth to support multiple systems and to adopt MicroTCA as a crate technology. The architecture was utilized on various beamlines around the Fermilab complex including PIP2IT, FAST/IOTA and the Muon Delivery Ring. In summary, we were able to develop a data acquisition framework which incrementally replaces VxWorks & VME hardware as well as increases our total bandwidth to 10 Gbit/s using off the shelf Ethernet technology