The chemical composition of normal stellar atmospheres

Spectroscopic analysis of stellar atmosphere chemical compositio

Planetary nebulae and the interstellar medium

In addition to available published data on planetary nebulae (PN), some 40 objects largely concentrated towards the galactic center and anticenter regions were included. All were observed with the Lick 3(sup m) telescope and image tube scanner. Abundances of C, N, O, Ne, Cl, and Ar were determined by a procedure in which theoretical models were used to obtain ionization correction factors (ICF). Of the 106 PN, 66 are N-rich and 40 are N-poor. There appear to be no significant differences between the average compositions in the solar neighborhood and the average taken over the entire observable portion of the galaxy

Analysis of high excitation planetary nebulae

Combination of extensive ground-based spectroscopic observation of high excitation planetary with IUE data permit determination not only of improved diagnostics but also better abundances for elements such as C and N that are well represented in the ultraviolet spectra and also C, Ar and metals Na, Ca and K whose lines appear in the wavelength 3200-8100 A region

The world trade network and the environment

This papers analyses the role of the world trade network on the environment. We rely on methods developed for social network analysis to identify the most important countries in connecting trade between all the other countries in the world trade network. We then estimate how the network or indirect effects from trade affect the environmental quality of a country. As the trade networks are endogenously determined by trade and environmental conditions, we use as instrumental variables the growth in the population of trade partners and the growth in the population of trade partners' partners to exploit exogenous variation in the world trade network. Once we simultaneously estimate the environmental, trade, income and network equations using a three-stage least square procedure, we find that network effects harm the environmental quality of developed countries but improve the environment of developing countries

The Legislative Recycling Bin: A Reevaluation of the Policy Process

Congressional scholarship has long sought to understand the conditions under which a member of Congress is successful in converting a policy idea into a law. Two areas of this research, the bill sponsorship literature and the legislative effectiveness literature, have developed scholarly understanding on both the motivations and outcomes of bill sponsorship, as well as illuminating the conditions under which a bill is more likely to become law. The empirical approaches of these areas of study however, do not adequately capture the complexities of Congress. Most studies of the legislative process treat bill sponsorship and the policy process as a linear progression wherein an individual bill is introduced and either passes or fails in a given Congress. Using a mixed-methods research design, this study demonstrates that a substantial amount of legislation in a given Congress has either been introduced in previous Congresses, or will be reintroduced in subsequent Congresses. As a result, many bills are not independent pieces of legislation, but rather, are “recycled” throughout time. Utilizing pooled data from the 96th to 113th Congresses (1979-2015) and new variables identifying recycled bills, this study determines that legislative recycling affects the scheduling of bills from committee and the likelihood of legislative success for members of the United States House of Representatives. Across multiple levels of analysis, recycled bills are found to be negatively associated with the likelihood of success, and patterns of legislative recycling indicate that some policy areas are more likely to have repeated bill introductions than others. In a legislative case study of the Congressional Tri-Caucus’s Health Equity and Accountability Act (HEAA), this study reviews the historical, institutional, and internal dimensions of a recycled policy proposal, finding that motivations for the reintroduction of HEAA include, but also extend beyond, the narrow purpose of lawmaking. Taken in sum, the study of legislative recycling adds both analytical and conceptual clarity to the study of Congress, and provides a number of departure points for future research

Studies of the Solar System and Probable Lunar Abundances of Elements of Geochemical and Metallurgical Significance Status Report

Lunar abundances of elements of geochemical and metallurgical significanc

Dual-Frequency VSOP Observations of AO 0235+164

AO 0235+164 is a very compact, flat spectrum radio source identified as a BL Lac object at a redshift of z=0.94. It is one of the most violently variable extragalactic objects at both optical and radio wavelengths. The radio structure of the source revealed by various ground-based VLBI observations is dominated by a nearly unresolved compact component at almost all available frequencies. Dual-frequency space VLBI observations of AO 0235+164 were made with the VSOP mission in January-February 1999. The array of the Japanese HALCA satellite and co-observing ground radio telescopes in Australia, Japan, China and South Africa allowed us to study AO 0235+164 with an unprecedented angular resolution at frequencies of 1.6 and 5 GHz. We report on the sub-milliarcsecond structural properties of the source. The 5-GHz observations led to an estimate of T_B > 5.8 x 10^{13} K for the rest-frame brightness temperature of the core, which is the highest value measured with VSOP to date.Comment: 8 pages, 8 figures, to appear in Publ. Astron. Soc. Japa