Fair Hearing in Administrative Rule-Making: A Recent Experience Under the Federal Food, Drug, and Cosmetic and Fair Packaging and Labeling Acts

In promulgating regulations to govern the labeling of foods under the Fair Packaging and Labeling Act, the Commissioner of Food and Drugs, despite the objections of adversely affected parties, denied all requests for a public hearing. In this article the author reviews the hearing provisions of the Act, analyzes the position taken by the Food and Drug Administration, and concludes that the failure to grant a trial-type hearing on the labeling regulations was legally indefensible

Detailed Spectral Analysis of the Type Ib Supernova 1999dn. Paper I: Hydrogen-free Models

We present spectral fits to five epochs of the typical Type Ib supernova 1999dn using the generalized, non-LTE, stellar atmospheres code PHOENIX. Our goal is threefold: to determine basic physical properties of the supernova ejecta, such as velocity, temperature, and density gradients; to reproduce He I absorption lines by invoking non-thermal excitation; and, to investigate possible spectral signatures of hydrogen, especially a feature around 6200 Angstrom, which has been attributed to high velocity $H_\alpha$. Our models assume an atmosphere with uniform composition devoid of any hydrogen. Our model spectra fit the observed spectra well, successfully reproducing most of the features, including the prominent He I absorptions. The most plausible alternative to $H_\alpha$ as the source of the 6200 Angstrom feature is a blend of Fe II and Si II lines, which can be made stronger to fit the observed feature better by increasing the metallicity of the ejecta. High-metallicity models fit well at early epochs, but not as well as solar-metallicity models after maximum light. While this blend of metal lines is a reasonable explanation of the source of the 6200 Angstrom feature, it is still important to investigate hydrogen as the source; therefore, a second paper will present models that include a thin shell of hydrogen around the main composition structure.Comment: 24 pages, 11 figures, 2 tables, submitted to Ap

Investing in Hope: AIDS, Life Expectancy, and Human Capital Accumulation

A three period overlapping generations model is developed to investigate the impact of shorter life expectancy due to disease, on human capital investment decisions and income growth. This research is particularly relevant to Sub-Saharan Africa given the dramatic reduction in life expectancy due to HIV/AIDS and the potential lasting effects on growth. Our results indicate that as life expectancy shortens so does schooling inducing a lower growth rate of income. These relationships are even more pronounced for the African continent than for the rest of the world.HIV/AIDS, Africa, life expectancy, growth, overlapping generations.

Accounting for Agricultural Decline with Economic Growth in Taiwan

In this paper we propose an empirical model to decompose the evolution of the agricultural GDP share of Taiwan into three components: price changes, factor endowment changes and technological change. The full sample period is 1967 to 1997. The data were first tested to assess whether the time series are nonstationary and cointegrated. After confirming their nonstationarity and cointegrated relation- ship, we then employ an error correction model (ECM) in the empirical estimation to capture the dynamic as well as long-run equilibrium relationship among those economic variables. The results suggest that relative prices have a positive influence on the share of agriculture in GDP in both the long-run and the short-run. An increase in capital per unit of labor, on the other hand, is associated with a smaller agricultural share. This result is consistent with the Rybczynski Theorem. Technical change has been biased in favor of this sector. The strong negative impact of the change in factor endowments seems to dominate any possible positive effect of relative prices and technical change. This result makes a strong case for a Heckscher-Ohlin type model as a basis of understanding the development of the Taiwanese economy.Taiwan, productivity growth, GDP function, error correction,

Retention of a Primordial Cold Classical Kuiper Belt in an Instability-Driven Model of Solar System Formation

The cold classical population of the Kuiper belt exhibits a wide variety of unique physical characteristics, which collectively suggest that its dynamical coherence has been maintained through out the solar system's lifetime. Simultaneously, the retention of the cold population's relatively unexcited orbital state has remained a mystery, especially in the context of a solar system formation model, that is driven by a transient period of instability, where Neptune is temporarily eccentric. Here, we show that the cold belt can survive the instability, and its dynamical structure can be reproduced. We develop a simple analytical model for secular excitation of cold KBOs and show that comparatively fast apsidal precession and nodal recession of Neptune, during the eccentric phase, are essential for preservation of an unexcited state in the cold classical region. Subsequently, we confirm our results with self-consistent N-body simulations. We further show that contamination of the hot classical and scattered populations by objects of similar nature to that of cold classicals has been instrumental in shaping the vast physical diversity inherent to the Kuiper belt.Comment: 9 pages, 11 figures, accepted for publication in Ap

THE IMPACT OF LIFE EXPECTANCY IN HUMAN CAPITAL ACCUMULATION: AIDS

A three period overlapping generations model is developed to investigate the impact of shorter life expectancy due to disease, on human capital investment decisions and income growth. This research is particularly relevant to Sub-Saharan Africa given the dramatic reduction in life expectancy due to HIV/AIDS and the potential lasting effects on growth. Our results indicate that as life expectancy shortens so does schooling inducing a lower growth rate of income. These relationships are even more pronounced for the African continent than for the rest of the world.Health Economics and Policy, Labor and Human Capital,

Investing in Hope: AIDS, Life Expectancy, and Human Capital Accumulation

A three period overlapping generations model is developed to investigate the impact of shorter life expectancy due to disease, on human capital investment decisions and income growth. This research is particularly relevant to Sub-Saharan Africa given the dramatic reduction in life expectancy due to HIV/AIDS and the potential lasting effects on growth. Our results indicate that as life expectancy shortens so does schooling inducing a lower growth rate of income. These relationships are even more pronounced for the African continent than for the rest of the world.Labor and Human Capital,

Spectral Evolution of an Earth-Like Planet

We have developed a characterization of the geological evolution of the Earths atmosphere and surface in order to model the observable spectra of an Earth-like planet through its geological history. These calculations are designed to guide the interpretation of an observed spectrum of such a planet by future instruments that will characterize exoplanets. Our models focus on spectral features that either imply habitability or are required for habitability. These features are generated by H2O, CO2, CH4, O2, O3, N2O, and vegetation-like surface albedos. We chose six geological epochs to characterize. These epochs exhibit a wide range in abundance for these molecules, ranging from a CO2 rich early atmosphere, to a CO2/CH4-rich atmosphere around 2 billion years ago to a present-day atmosphere. We analyzed the spectra to quantify the strength of each important spectral feature in both the visible and thermal infrared spectral regions, and the resolutions required to unambiguously observe the features for each epoch. We find a wide range of spectral resolutions required for observing the different features. For example, H2O and O3 can be observed with relatively low resolution, while O2 and N2O require higher resolution. We also find that the inclusion of clouds in our models significantly affects both the strengths and resolutions required to observe all spectral features.Comment: 34 pages, 24 fig, pdf, ApJ, TB