What is the Natural Size of Supersymmetric CPCP Violation?

It is well known that if phases and masses in the Minimal Supersymmetric Standard Model (MSSM) are allowed to have general values, the resulting neutron EDM ($d_n$) exceeds the experimental upper limit by about $10^3$. We assume that the needed suppression is not due to a fine-tuning of phases or masses, and ask what natural size of $CP$ violation (CPV) results. We show that (1) the phase of one of the superpotential parameters, $\mu$, does not contribute to any CPV in the MSSM and so is not constrained by \dn; (2) the MSSM contribution to $d_n$ is tiny, just coming from the CKM phase; (3) the phases in the MSSM cannot be used to generate a baryon asymmetry at the weak scale, given our assumptions; and (4) in non-minimal SUSY models, an effective phase can enter at one loop giving $d_n \sim 10^{-26}$\ecm, $d_e \sim 10^{-27}$\ecm, and allowing a baryon asymmetry to be generated at the weak scale, without fine-tunings. Our results could be evaded by a SUSY breaking mechanism which produced phases for the SUSY breaking parameters that somehow were naturally of order $10^{-3}$.Comment: 13pp (no figs), REVTEX (LATEX), TRI-PP-93-

Knowledge Economy Immigration: A Priority for U.S. Growth Policy

Offers economic and political arguments for facilitating immigration of highly educated, skilled workers as a way to support long-term knowledge-based economic growth. Proposes granting green cards to math and science graduates of qualified U.S. colleges

Hydrology of the Central Arctic River Basins of Alaska

The work upon which this report is based was supported in part by funds (Project A-031-ALAS) provided by the United States Department of Interior, Office of Water Resources Research, as authorized under the Water Resources Act of 1964, as amended

Effects of seasonability and variability of streamflow on nearshore coastal areas: final report

General nature and scope of the study: This study examines the variability of streamflow in all gaged Alaskan rivers and streams which terminate in the ocean. Forty-one such streams have been gaged for varying periods of time by the U. S. Geological Survey, Water Resources Division. Attempts have been made to characterize streamflow statistically using standard hydrological methods. The analysis scheme which was employed is shown in the flow chart which follows. In addition to the statistical characterization, the following will be described for each stream when possible: 1. average period of break-up initiation (10-day period) 2. average period of freeze-up (10-day period) 3. miscellaneous break-up and freeze-up data. 4. relative hypsometric curve for each basin 5. observations on past ice-jam flooding 6. verbal description of annual flow variation 7. original indices developed in this study to relate streamflow variability to basin characteristics and regional climate.This study was supported under contract 03-5-022-56, Task Order #4, Research Unit #111, between the University of Alaska and NOAA, Department of Commerce to which funds were provided by the Bureau of Land Management through an interagency agreement

Measuring Risk Aversion From Excess Returns on a Stock Index

We distinguish the measure of risk aversion from the slope coefficient in the linear relationship between the mean excess return on a stock index and its variance. Even when risk aversion is constant, the latter can vary significantly with the relative share of stocks in the risky wealth portfolio, and with the beta of unobserved wealth on stocks. We introduce a statistical model with ARCH disturbances and a time-varying parameter in the mean (TVP ARCH-N). The model decomposes the predictable component in stock returns into two parts: the time-varying price of volatility and the time-varying volatility of returns. The relative share of stocks and the beta of the excluded components of wealth on stocks are instrumented by macroeconomic variables. The ratio of corporate profit over national income and the inflation rate ore found to be important forces in the dynamics of stock price volatility.

How Big is the Tax Advantage to Debt?

This paper uses an option valuation model of the firm to answer the question, "What magnitude tax advantage to debt is consistent with the range of observed corporate debt ratios?" We incorporate into the model differential personal tax rates on capital gains and ordinary income. We conclude that variations in the magnitude of bankruptcy costs across firms can not by itself account for the simultaneous existence of levered and unlevered firms. When it is possible for the value of the underlying assets to junip discretely to zero, differences across firms in the probability of this jump can account for the simultaneous existence of levered and unlevered firms. Moreover, if the tax advantage to debt is small, the annual rate of return advantage offered by optimal leverage may be so small as to make the firm indifferent about debt policy over a wide range of debt-to-firm value ratios.

Information Is the Key to Patient Empowerment

Mr. Kane\u27s paper examines the role of patients to ensure that they have both the knowledge and power to direct their health care choices. The evolving health care market place is discussed to emphasize the increased importance of individual involvement in health decision making. A checklist sets forth questions which a patient should ask of herself and of her provider before entering into health care decisions

Relationship of Main Pulmonary Artery Diameter to Pulmonary Arterial Pressure in Scleroderma Patients with and without Mild to Moderate Interstitial Fibrosis

Purpose: To determine the validity of main pulmonary artery diameter (MPAD) as a marker of pulmonary hypertension in scleroderma patients with and without interstitial lung disease (lLD). Materials and Methods: We cross-referenced the radiologic database with medical records to identify patients with both computed tomography (CT) scans of the chest and right-heart catheterization separated by no more than six months. Computed tomography scans were reviewed to determine MPAD and extent of ILD for each patient. Ground glass opacity and fibrosis were individually scored by a single thoracic radiologist on a five-point scale. The same radiologist also determined the quality of delineation for the great vessels. MPAD was calculated based on the average of measurements taken from two separate observers. Mean pulmonary arterial pressures (mPAP) were determined by RHC. Patients were divided into either group A (n = 20) or group B (n = 27) based on the absence or presence of interstitial fibrosis respectively. Patients with available data from pulmonary function tests (PFTs) were divided into those with FVC \u3e 70% predicted (Group C) and those with FVC \u3c 70% predicted (Group D). Groups were compared using either the Student t test or Mann-Whitney U test depending on the distribution of each variable under consideration. Either the Pearson correlation coefficient or the Spearman rank-correlation coefficient was calculated for each group to evaluate the relationship between MPAD and mPAP. Results: Groups A and B were similar with regard to MPAD (p = 0.28) and mPAP (p = 0.34) upon Mann-Whitney U testing. MPAD was strongly correlated with mPAP in both Group A (r = 0.68, P = 0.001) and Group B (r = 0.70, P \u3c 0.0001). The correlation between MPAD and mPAP in Group C (r = 0.69, P = 0.002) was substantially higher than that in Group 0 (r = 0.42, P = 0.11). Conclusion: In our patient sample with scleroderma, MPAD is strongly correlated with mPAP and may indicate the development of pulmonary hypertension regardless of the presence of mild to moderate interstitial fibrosis. An increase in the severity of restrictive lung disease as measured by FVC appears to attenuate the correlation between MPAO and mPAP