Complex eigenvalues and trend-reverting fluctuations

Autoregressions of quarterly or annual aggregate time series provide evidence of trend-reverting output growth and of short-term dynamic adjustment that appears to be governed by complex eigenvalues. This finding is at odds with the predictions of reasonably parameterized, convex one-sector growth models, most of which have positive real characteristic roots. We study a class of one-sector economies, overlapping generations with finite life spans of L greater than or equal to 3, in which aggregate saving depends nontrivially on the distribution of wealth among cohorts. If consumption goods are weak gross substitutes near the steady state price vector, we prove that the unique equilibrium of a life cycle exchange economy converges to the unique steady state via damped oscillations. We also conjecture that this form of trend reversion extends to production economies with a relatively flat factor-price frontier, and we test this conjecture in several plausible parameterizations of 55-period life cycle economies.Time-series analysis ; Econometric models ; Regression analysis

Manufacturing Mechatronics Using Thermal Spray Shape Deposition

A new technology for manufacturing mechatronics is described. The technique is based on recursive masking and deposition of thermally sprayed materials. Using these methods, mechanical structures can be created that embed and interconnect electronic components. This results in highly integrated mechatronic devices. A simple, electromechanical artifact was designed and produced to assess the feasibility of these techniques. The details and limitations of this project will be discussed. Areas of future research are identified which are aimed at realizing the full potential of this emerging manufacturing process.Mechanical Engineerin

Mojave Applied Ecology Notes Fall 2009

USDA working to manage invasive annual grasses, effects of heat and smoke on red brome soil seed bank, how burial depth and substrate affect germination of Sahara mustard and red brome, environmental effects of the southern Nevada groundwater projec

Sputtering yield measurements at glancing incidence using a quartz crystal microbalance

Low energy sputtering yields at grazing incidence have been investigated experimentally using a quartz crystal microbalance (QCM) technique. This method involved precoating the QCM with a thin film of the desired target material and relating the resonance frequency shift directly to mass loss during ion bombardment. A highly focused, low divergence ion beam provided a well defined incidence angle. Focusing most of the ion current on the center of the target allowed for higher sensitivity by taking into account the radial mass sensitivity of the QCM. Measurements of Mo, Cu, and W sputtering yields were taken for low energy (80–1000 eV) Xe+ and Ar+ to validate this experimental method. The target films ranged from 3.5 to 8.0 µm in thickness and were deposited so that their crystal structure and density would match those of the bulk material as closely as possible. These properties were characterized using a combination of scanning electron microscope imagery, profilometry, and x-ray diffraction. At normal incidence, the sputtering yields demonstrated satisfactory agreement with previously published work. At angles of incidence up to 40° off normal, the data agreed well with predictions from existing theoretical models. Sputtering yields were found to increase by a factor of 1.6 over this range. The optimum angle for sputtering occurred at 55°, after which the yields rapidly decreased. Measurements were taken up to 80° from the surface normal

Excited ionic and neutral fragments produced by dissociation of the N2(+)* H band

N I and N II fluorescent radiation was observed when N2 was irradiated by undispersed synchrotron radiation with an upper energy limit of approximately 200 eV. The excited fragments originate from dissociation of a band of excited ionic states of N2 lying between 34.7 and 44 eV

Graduate Training and Productivity: A Look at Who Publishes

In two recent studies, Morgan and Fitzgerald and Robey ranked American political science departments on the basis of their faculty\u27s research productivity in the major political science journals. The rankings which they produced were at some variance with the reputational rankings reported by Somit and Tanenhaus, Cartter, and, more recently, Ladd and Lipset. In particular, Robey reports that “… some southern universities seem to have made great strides in the last ten years while some Ivy League schools do not seem to be producing at a rate equivalent with their reputations.” Morgan and Fitzgerald reach a similar conclusion about the relationship between reputation and productivity for the Ivy League and southern schools. These studies and their implications have generated a great deal of discussion among political scientists and, as might be expected, have been subjected to a variety of criticism. Criticisms, for example, have focused on the journals selected to measure productivity, the use of frequency of articles produced rather than their importance for the profession, and the failure to incorporate books and monographs in such evaluations

Galactic Scale Feedback Observed in the 3C 298 Quasar Host Galaxy

We present high angular resolution multi-wavelength data of the 3C 298 radio-loud quasar host galaxy (z=1.439) taken using the W.M. Keck Observatory OSIRIS integral field spectrograph with adaptive optics, Atacama Large Millimeter/submillimeter Array (ALMA), Hubble Space Telescope (HST) WFC3, and the Very Large Array (VLA). Extended emission is detected in the rest-frame optical nebular emission lines H$\beta$, [OIII], H$\alpha$, [NII], and [SII], as well as molecular lines CO (J=3-2) and (J=5-4). Along the path of 3C 298's relativistic jets we detect conical outflows of ionized gas with velocities up to 1700 km s$^{-1}$ and outflow rate of 450-1500 M$_\odot$yr$^{-1}$. Near the spatial center of the conical outflow, CO (J=3-2) emission shows a molecular gas disc with a total molecular mass ($\rm M_{H_{2}}$) of 6.6$\pm0.36\times10^{9}$M$_{\odot}$. On the molecular disc's blueshifted side we observe a molecular outflow with a rate of 2300 M$_\odot$yr$^{-1}$ and depletion time scale of 3 Myr. We detect no narrow H$\alpha$ emission in the outflow regions, suggesting a limit on star formation of 0.3 M$_\odot$yr$^{-1}$kpc$^{-2}$. Quasar driven winds are evacuating the molecular gas reservoir thereby directly impacting star formation in the host galaxy. The observed mass of the supermassive black hole is $10^{9.37-9.56}$M$_{\odot}$ and we determine a dynamical bulge mass of 1-1.7$\rm\times10^{10}\frac{R}{1.6 kpc}$ M$_{\odot}$. The bulge mass of 3C 298 resides 2-2.5 orders of magnitude below the expected value from the local M$\rm_{bulge}-M_{BH}$ relationship. A second galactic disc observed in nebular emission is offset from the quasar by 9 kpc suggesting the system is an intermediate stage merger. These results show that galactic scale negative feedback is occurring early in the merger phase of 3C 298, well before the coalescence of the galactic nuclei and assembly on the local relationship.Comment: 23 pages, 11 figures, 4 tables, Accepted for publication in the Astrophysical Journa

A Framework for XML-based Integration of Data, Visualization and Analysis in a Biomedical Domain

Biomedical data are becoming increasingly complex and heterogeneous in nature. The data are stored in distributed information systems, using a variety of data models, and are processed by increasingly more complex tools that analyze and visualize them. We present in this paper our framework for integrating biomedical research data and tools into a unique Web front end. Our framework is applied to the University of Washington’s Human Brain Project. Specifically, we present solutions to four integration tasks: definition of complex mappings from relational sources to XML, distributed XQuery processing, generation of heterogeneous output formats, and the integration of heterogeneous data visualization and analysis tools