Targeted Advertising and Voter Turnout: An Experimental Study of the 2000 Presidential Election

Scholars disagree whether negative advertising demobilizes or stimulates the electorate. We use an experiment with over 10,200 eligible voters to evaluate the two leading hypotheses of negative political advertising. We extend the analysis to examine whether advertising differentially impacts the turnout of voter subpopulations depending on the advertisement痴 message. In the short term, we find no evidence that exposure to negative advertisements decreases turnout and little that suggests it increases turnout. Any effect appears to depend upon the message of the advertisement and the characteristics of the viewer. In the long term, we find little evidence that the information contained in the treatment groups・advertisements is sufficient to systematically alter turnout.

Political Science and the FDA

This essay collects and analyzes the important political science works on FDA, with an eye both to serving as a springboard for future research on FDA decision-making and to drawing conclusions from extant research

Optical waveguide arrays: quantum effects and PT symmetry breaking

Over the last two decades, advances in fabrication have led to significant progress in creating patterned heterostructures that support either carriers, such as electrons or holes, with specific band structure or electromagnetic waves with a given mode structure and dispersion. In this article, we review the properties of light in coupled optical waveguides that support specific energy spectra, with or without the effects of disorder, that are well-described by a Hermitian tight-binding model. We show that with a judicious choice of the initial wave packet, this system displays the characteristics of a quantum particle, including transverse photonic transport and localization, and that of a classical particle. We extend the analysis to non-Hermitian, parity and time-reversal ($\mathcal{PT}$) symmetric Hamiltonians which physically represent waveguide arrays with spatially separated, balanced absorption or amplification. We show that coupled waveguides are an ideal candidate to simulate $\mathcal{PT}$-symmetric Hamiltonians and the transition from a purely real energy spectrum to a spectrum with complex conjugate eigenvalues that occurs in them.Comment: 16 pages, 12 figures, Invited Review for European Physics Journal - Applied Physic

The Interaction of Nitrogen and Moisture on Crop Yield and Water Use

In recent years, a subject of considerable speculation among South Dakota farmers is whether or not the use of nitrogenous fertilizers is profitable under conditions of dryland farming. There has been a prejudice against the use of nitrogenous fertilizers as giving a leafy, succulent growth, liable to drought damage. Frequent claims are that additions of nitrogen result in “burning” of crops when moisture conditions become unfavorable, and that under these conditions yields are often better without the use of fertilizer. A common explanation is that fertilized crops use more water than unfertilized crops and this results in the fertilized crops having less chance to reach maturity when the moisture is limited. The objectives of this study were to determine the effect if nitrogenous fertilizer applications on the yield and moisture use of crops grown under various conditions of moisture supply. These objectives were pursued in experiments conducted in the field where it was anticipated that considerable natural moisture stress would occur, and in the greenhouse, some with no control over moisture conditions and others with controlled moisture. In some experiments, partial biochemical analysis of plants were made in an endeavor to find a physiochemical basis for observed results. It is hoped that the results of this investigation will serve in the aid in making better recommendations with regard to the application of nitrogenous fertilizers to crops under conditions of limited moisture

Dosage compensation in birds

AbstractThe Z and W sex chromosomes of birds have evolved independently from the mammalian X and Y chromosomes [1]. Unlike mammals, female birds are heterogametic (ZW), while males are homogametic (ZZ). Therefore male birds, like female mammals, carry a double dose of sex-linked genes relative to the other sex. Other animals with nonhomologous sex chromosomes possess “dosage compensation” systems to equalize the expression of sex-linked genes. Dosage compensation occurs in animals as diverse as mammals, insects, and nematodes, although the mechanisms involved differ profoundly [2]. In birds, however, it is widely accepted that dosage compensation does not occur [3–5], and the differential expression of Z-linked genes has been suggested to underlie the avian sex-determination mechanism [6]. Here we show equivalent expression of at least six of nine Z chromosome genes in male and female chick embryos by using real-time quantitative PCR [7]. Only the Z-linked ScII gene, whose ortholog in Caenorhabditis elegans plays a crucial role in dosage compensation [8], escapes compensation by this assay. Our results imply that the majority of Z-linked genes in the chicken are dosage compensated

Performance and power regulation characteristics of two aileron-controlled rotors and a pitchable tip-controlled rotor on the Mod-O turbine

Tests were conducted on the DOE/NASA mod-0 horizontal axis wind turbine to compare and evaluate the performance and the power regulation characteristics of two aileron-controlled rotors and a pitchable tip-controlled rotor. The two aileron-controlled rotor configurations used 20 and 38 percent chord ailerons, while the tip-controlled rotor had a pitchable blade tip. The ability of the control surfaces to regulate power was determined by measuring the change in power caused by an incremental change in the deflection angle of the control surface. The data shows that the change in power per degree of deflection angle for the tip-controlled rotor was four times the corresponding value for the 2- percent chord ailerons. The root mean square power deviation about a power setpoint was highest for the 20 percent chord aileron, and lowest for the 38 percent chord aileron