AIDing Contraception: HIV and Recent Trends in Abortion Rates

Since the onset of HIV/AIDS awareness in the early 1980s, much attention has centered around the substantial negative effects of the disease throughout the world. This paper provides evidence of a secondary effect the disease has had on sexual behavior in the United States. Using a difference-in-differences estimation framework and state level data, we show that the perceived threat of HIV resulted in a drop in unwanted pregnancies, as demonstrated by a lower incidence of abortions. Our results suggest that each additional reported case of HIV per 1,000 individuals resulted in 85.5 fewer abortions per 1,000 live births.HIV, abortion, fertility

Long Term Trends in Fair and Unfair Inequality in the United States

This paper analyzes the microeconomic sources of wage inequality in the United States from 1967-2012. Decomposing inequality into factors categorized by degree of personal responsibility, we find that education is able to explain more than twice as much of inequality today as 45 years ago. However, neither hours worked nor education, industry, marital status, or geographical location is able to explain the observed general rise in inequality. In fact, "unfair" inequality has risen faster than "fair" inequality, regardless of the set of variables chosen as fair sources of inequality (resulting from responsibility factors). We also examine inequalities within gender and racial groups and across U.S. states. Several noteworthy findings emerge. Wage inequality among males used to be lower than among females until 1990, but today the opposite is true. We also find several occasions where the distinction between the raw Gini and the Gini adjusted for certain characteristics produces different conclusions. For instance, raw inequality among black females decreased since 1969, but if we acknowledge differences resulting from hours worked and educational outcomes as "fair" inequalities, the remaining inequality measure has increased. We also find that there is substantial geographic heterogeneity in trends of unfair and overall inequality

Safe Architectural Design Principles

This report discusses architectures for safety-critical systems. The report summarises the existing literature in the area as well as the guidance provided by existing safety-critical system development standards. We discuss the three constituent functions of fault tolerant architectures: error detection, damage assessment and confinement and error recovery. We also consider methods for fault prevention

Hazard Analysis of Interactive Systems

This report discusses approaches to analysis of safety-critical systems for operator error. The report summarises the existing literature in the area as well as the guidance provided by existing safety-critical system development standards

Explaining Inequality Between Countries: The Declining Role of Political Institutions

Within the fundamental determinants of cross-country income inequality, ‘humanly devised’ political institutions represent a hallmark factor that societies can influence, as opposed to, for example, geography. Focusing on the portion of inequality explainable by differences in political institutions, we decompose annual cross-country Gini coefficients for 95 countries (representing 85 percent of the world population) from 1960-2012. Since 1988, inequality has marginally decreased (from a Gini of 0.525 to 0.521) but the portion that cannot be explained by political institutions has increased substantially (from 0.411 to 0.459). Specifically, the explanatory power of institutions fell rapidly from the late 1980s to the early 1990s. This result prevails when using alternative variables, expanding the sample, weighting countries by population size, and controlling for the remaining fundamental determinants of income: culture and education. Over the same timeframe, the explanatory power of geographical conditions has been rising. This phenomenon appears to be global and is unlikely to be driven by contemporary regional events alone, such as the fall of the Soviet Union, Asian success stories (e.g., China), or institutional monocropping in Africa. A corollary of our finding implies that, if we hold societies responsible for their political institutions, inequality has become notably less fair since the late 1980s

Styles, textural evolution, and sulfur isotope systematics of Cu-rich sulfides from the Cambrian Whalesback volcanogenic massive sulfide deposit, central Newfoundland, Canada

The Whalesback Cu-rich volcanogenic massive sulfide deposit in the Newfoundland Appalachians is a highly deformed deposit found on a steep limb of a closed and boudinaged overturned fold. The deposit was intensely deformed at low temperature but medium pressure (>175 MPa) during the accretion of the composite Lushs Bight oceanic tract-Dashwoods terrane onto the Humber margin at ca. 480 Ma. The ore mineralogy consists of chalcopyrite, pyrrhotite, and pyrite with lesser sphalerite and trace Ag, Bi, and Hg tellurides. Four styles of sulfide mineralization are present: (1) disseminated (5%); (2) vein (50%); (3) breccia (25%); and (4) semimassive to massive (20%). Independent of mineralization style, massive pyrite and pyrrhotite (and some chalcopyrite) are commonly parallel to main S2 schistosity in the deposit, whereas late chalcopyrite piercement veins occur at a high angle to S2. The progressive increase in pressure and temperature produced a remobilization sequence wherein sphalerite was the first sulfide phase to cross the brittle-ductile boundary, followed by pyrrhotite and, finally, chalcopyrite. Maximum temperature was not high enough for the pyrite to cross the brittle-ductile boundary. Instead, pyrite grains were incorporated and transported by pyrrhotite and chalcopyrite during the ductile remobilization events, rounding and fracturing them. Remobilization of the sulfides occurred mainly by plastic flow, but some solution transport and reprecipitation is locally observed. In situ secondary ion mass spectrometry sulfur isotope geochemistry of sulfides yielded values of δ34S ranging from 2.7‰ to 4.7‰ for pyrite, 2.1‰ to 4.0‰ for pyrrhotite, and 1.3‰ to 4.7‰ for chalcopyrite. Sulfur isotope modeling suggests that at least 60% of the sulfur was derived from leaching of igneous rocks (i.e., basalts), with the remainder derived from thermochemical sulfate reduction of seawater sulfate during alteration of the basalts by seawater. At the deposit scale, sulfur isotopes retained their original signature and did not reequilibrate during the secondary deformation and remobilization events.PostprintPeer reviewe

Experimental and Theoretical (e,2e) Ionization Cross Sections for a Hydrogen Target at 75.3 eV Incident Energy in a Coplanar Asymmetric Geometry

Very recently it was shown that the molecular three-body distorted wave (M3DW) approach gives good agreement with the shape of the experimental data for electron-impact ionization of H2 in a coplanar symmetric geometry, providing the incident electrons have an energy of 35 eV or greater. One of the weaknesses of these studies was that only the shape of the cross section could be compared to experiment, since there was no absolute or relative normalization of the data. Here we report a joint experimental/theoretical study of electron-impact ionization of H2 in a coplanar asymmetric geometry where the energy of the incident electron was fixed, and different pairs of final state electron energies were used. In this case, the experimental data can be normalized such that only one renormalization factor is required. It is shown that the M3DW is pretty good in agreement with experiment. However, a better treatment of polarization and exchange between the continuum and bound state electrons is required before quantitative agreement between experiment and theory is achieved

The Associations Between Park Environments and Park Use in Southern US Communities

Purpose To document park use and park and neighborhood environment characteristics in rural communities, and to examine the relationship between park characteristics and park use. Methods The System for Observing Play and Recreation in Communities measured use in 42 target areas across 6 community parks in May 2010 and October 2010. Direct observation instruments were used to assess park and neighborhood environment characteristics. Logistic regression was used to determine the relationship between the condition, number of amenities, and number of incivilities in a target area with target area use. Findings Ninety‐seven people were observed across all parks during May 2010 data collection and 116 people during October 2010 data collection. Low park quality index scores and unfavorable neighborhood environment characteristics were observed. There was a significant positive association between number of incivilities in a target area and target area use (OR = 1.91; 95% CI: 1.09‐3.38; P = .03). Conclusions The number of people observed using the parks in this study was low, and it was considerably less than the number observed in other studies. The objective park and neighborhood environment characteristics documented in this study provide a more comprehensive understanding of parks than other studies. Further examining the complex relationship between park and neighborhood environment characteristics and park use is important, as it can inform park administrators and city planners of characteristics that are best able to attract visitors.Peer Reviewedhttp://deepblue.lib.umich.edu/bitstream/2027.42/108592/1/jrh12071.pd

AIDing Contraception: HIV and Recent Trends in Abortion Rates

Since the onset of HIV/AIDS awareness in the early 1980s, much attention has centered around the substantial negative effects of the disease throughout the world. This paper provides evidence of a secondary effect the disease has had on sexual behavior in the United States. Using a difference-in-differences estimation framework and state level data, we show that the perceived threat of HIV resulted in a drop in unwanted pregnancies, as demonstrated by a lower incidence of abortions. Our results suggest that each additional reported case of HIV per 1,000 individuals resulted in 85.5 fewer abortions per 1,000 live births

AIDing Contraception: HIV and Recent Trends in Abortion Rates

Since the onset of HIV/AIDS awareness in the early 1980s, much attention has centered around the substantial negative effects of the disease throughout the world. This paper provides evidence of a secondary effect the disease has had on sexual behavior in the United States. Using a difference-in-differences estimation framework and state level data, we show that the perceived threat of HIV resulted in a drop in unwanted pregnancies, as demonstrated by a lower incidence of abortions. Our results suggest that each additional reported case of HIV per 1,000 individuals resulted in 85.5 fewer abortions per 1,000 live births