Cracking the Conundrum

From 2004 to 2006, the FOMC raised the target federal funds rate by 4.25%, yet long-maturity yields and forward rates fell. We consider several possible explanations for this "conundrum." The most likely, in our view, is a fall in the term premium, probably associated with some combination of diminished macroeconomic and financial market volatility, more predictable monetary policy, and the state of the business cycle.

In vivo contact stresses at the radiocarpal joint using a finite element method of the complete wrist joint

A small number of cadaveric studies have been carried out looking at the force transmission through the radiocarpal joint. In this study subject specific finite element models were created of the whole wrist joint using measured biomechanical data to capture the forces acting on the wrist with the hand generating a maximum gripping force

Investigation of wheat coleoptile response to phototropic stimulations

This report provides a summary of the preparations for, and the conduct and post-flight data analysis of, the Spacelab flight investigation FOTRAN, which flew on the IML-1 mission (STS-42) in January, 1992. The investigation was designed to provide data on the responses of wheat seedlings to various blue-light stimuli given while the plants were exposed to orbital microgravity conditions. Before the flight, a number of hypotheses were established which were to be tested by the data from the flight and parallel ground studies. A description of the experiment protocol developed for the mission is provided, and an account of the activities supported during preparations for and support of the flight experiment is given. Details of the methods used to reduce and analyze the data from the flight are outlined

Have Welfare-To-Work Programs Improved Over Time In Putting Welfare Recipients To Work?

Data from 76 experimental welfare-to-work programs conducted in the United States between 1983 and 1998 are used to investigate whether the impacts of such programs on employment had been improving over time and whether specific program features influencing such changes can be identified. Over the period, an increasing percentage of control group members received services similar to those offered to program group members. As a result, differential participation in program service activities between program and control group members decreased steadily over time. This reduction in the net receipt of program services tended to reduce the impact of these programs on employment. However, the negative influence of the reduced incremental services was offset by other factors that resulted in program impacts remaining essentially constant from 1983 to 1998. Suggestions are made for possibly improving program impacts in future experiments.Welfare Programs; Program Evaluation; Employment Behavior of Low-Income Families; Meta Analysis

The mesoscopic magnetron as an open quantum system

Motivated by the emergence of materials with mean free paths on the order of microns, we propose a novel class of solid state radiation sources based on reimplementing classical vacuum tube designs in semiconductors. Using materials with small effective masses, these devices should be able to access the terahertz range. We analyze the DC and AC operation of the simplest such device, the cylindrical diode magnetron, using effective quantum models. By treating the magnetron as an open quantum system, we show that it continues to operate as a radiation source even if its diameter is only a few tens of magnetic lengths.Comment: 11 pages, 7 figures; submitted to Physical Review Applie

A Check List of the Lepidoptera of Fulton County, Ohio With Special Reference to the Moths of Goll Woods State Nature Preserve

The results of a comprehensive 1988-1989 survey of the Lepidoptera in the 130 hectare Goll Woods State Nature Preserve in Fulton County, Ohio are presented. In addition many records of butterflies and skippers outside the confines of the Pre­ serve are presented for the first time. This is the fifth in a series of papers featuring the current status of lepidopterous fauna in Ohio\u27s recreational areas. A total of 27 species of skippers, 51 species of butterflies and 394 species of moths was identified and tabulated for the county. Three species on this list are classified as endangered, Epidemia helloides, Lithophane semiusta and Ufeus plicatus, and two are threatened, Speyeria idalia and Clossiana selene. Although locally abundant, Lithophane semiusta Grote is known to occur only at this site in Ohio. A single specimen of Ufeus plicatus was taken and is the only known specimen for the state

Two-channel Kondo physics in odd impurity chains

We study odd-membered chains of spin-(1/2) impurities, with each end connected to its own metallic lead. For antiferromagnetic exchange coupling, universal two-channel Kondo (2CK) physics is shown to arise at low energies. Two overscreening mechanisms are found to occur depending on coupling strength, with distinct signatures in physical properties. For strong inter-impurity coupling, a residual chain spin-(1/2) moment experiences a renormalized effective coupling to the leads; while in the weak-coupling regime, Kondo coupling is mediated via incipient single-channel Kondo singlet formation. We also investigate models where the leads are tunnel-coupled to the impurity chain, permitting variable dot filling under applied gate voltages. Effective low-energy models for each regime of filling are derived, and for even-fillings where the chain ground state is a spin singlet, an orbital 2CK effect is found to be operative. Provided mirror symmetry is preserved, 2CK physics is shown to be wholly robust to variable dot filling; in particular the single-particle spectrum at the Fermi level, and hence the low-temperature zero-bias conductance, is always pinned to half-unitarity. We derive a Friedel-Luttinger sum rule and from it show that, in contrast to a Fermi liquid, the Luttinger integral is non-zero and determined solely by the `excess' dot charge as controlled by gate voltage. The relevance of the work to real quantum dot devices, where inter-lead charge-transfer processes fatal to 2CK physics are present, is also discussed. Physical arguments and numerical renormalization group techniques are used to obtain a detailed understanding of these problems.Comment: 21 pages, 19 figure