12,057 research outputs found

    Probing Proton Strangeness with Time-Like Virtual Compton Scattering

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    We document that p(gamma,e+e-)p measurements will yield new, important information about the off-shell time-like nucleon form factors, especially in the phi meson region (q^2 = M^2_{phi}) governing the phi N couplings g^{V,T}_{\phi N N}. Calculations for p(gamma,e+e-)p, utilizing vector meson dominance, predict measurable phi enhancements at high |t| compared to the expected phi background production from pi, eta and Pomeron exchange. The phi form factor contribution generates a novel experimental signature for OZI violation and the proton strangeness content. The phi N couplings are determined independently from a combined analysis of the neutron electric form factor and recent high |t| phi photoproduction. The pi, eta and Pomeron transition form factors are also predicted and the observed pi and eta transition moments are reproduced.Comment: 9 pages, 6 figure

    The Labor Market Effects of the 1960s Riots

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    Between 1964 and 1971, hundreds of riots erupted in American cities, resulting in large numbers of injuries, deaths, and arrests, as well as in considerable property damage that was concentrated in predominantly black neighborhoods. There have been few studies of a systematic, econometric nature that examine the impact of the riots on the relative economic status of African Americans, or on the cities and neighborhoods in which the riots took. We present two complementary empirical analyses. The first uses aggregate, city-level data on income, employment, unemployment, and the area’s racial composition from the published volumes of the federal censuses. We estimate the “riot effect” by both ordinary least squares and two-stage least squares. The second empirical approach uses individual-level census data from the Integrated Public Use Microdata Series for 1950, 1970, and 1980. The findings suggest that the riots had negative effects on blacks’ income and employment that were economically significant and that may have been larger in the long run (1960-1980) than in the short run (1960- 1970). We view these findings as suggestive rather than definitive for two reasons. First, the data are not detailed enough to identify the precise mechanisms at work. Second, the wave of riots may have had negative spillover effects to cities that did not experience severe riots; if so, we would tend to underestimate the riots’ overall effect.

    HEALTH AND SAFETY REGULATION OF SMALL, HIGH-RISK SUBPOPULATIONS

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    The choice of decision framework used to set regulatory tolerance levels for hazardous substances can be divided into rigid and flexible tolerance levels. Rigid decision frameworks include zero or deminimis that fix risk levels for some subpopulation. and/or highly tolerances The accelerating identification of highly sensitive exposed individuals and the division of the population into ever smaller subpopulations at higher risk could prove to be tremendously burdensome on regulatory systems, particularly for rigid decision frameworks. Rigid tolerance levels, philosophically based on "rights" to zero or arbitrarily low excess risks for individuals, do not contain sufficient flexibility to account for small high-risk subpopulations. Furthermore, the equal protection for all such groups is an illusion, mainly because of the potentially large number of such subgroups and the relatively fixed regulatory resources. Thus, deminimis regulation is seen as a minimal but inadequate improvement over zero risk regulation. with improved measures of the heterogeneous demand for risk reduction by various high-risk subpopulations, augmented cost-benefit analyses leading to flexible tolEr2.nces could provide a richer analytic framework for more efficient regulatory decisions. Additionally, it may be useful to attempt to c2.tegorize hazards and subpopulations on the basis of the ability to self-protect.De minimis, sensitive, decision framework, cost benefit, Food Consumption/Nutrition/Food Safety, Health Economics and Policy,

    Johnson v. University Hospitals of Cleveland: Public Policy Over Traditional Principles

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    This Note will examine the policies and principles relating to the recovery of child rearing expenses in wrongful pregnancy or wrongful conception actions. This Note contends that the Johnson majority overemphasized certain policy considerations and was mistaken in allowing these policies to override traditional legal principles

    Technology Adoption, Management Practices, and Financial Performance of New and Beginning Farmers: Evidence from a National Survey

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    More than 50 percent of current farmers are over age 55, and the number of new farmers replacing them has fallen. This paper examines factors that contribute to the financial performance of new and beginning farmers in the U.S. A weighted regression analysis was used on data from the 2005 Agricultural Resource Management Survey (ARMS) to measure new and beginning farmers financial performance given farm and operator characteristics, production and marketing, and risk management strategies. Particular attention was given to the impact of technology adoption and management strategy on financial performance. Results indicate the adoption of Genetically Modified (GM) crops, having a written business plan, controlling variable costs, participation in coupled farm program payment, and participation in marketing contracts lead to higher financial performance while education, age, and off-farm work lowered financial performance for new and beginning farmers.financial performance, technology adoption, Genetically Modified (GM) crops, Business plan, new and beginning farmers, contracting, coupled farm program payments, Farm Management, Productivity Analysis,

    Whigs and Hunters: Indian Tribal Rights in the National Forests

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    7 pages. Contains 1 page of references
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