All That Sprawl, Y’all: An Analysis of Development on Steinwehr Avenue and York Street in Gettysburg, Pennsylvania, from 1971 to 2014

The advent of the automobile transformed the American landscape in the 20th century. In conjunction with the increasing importance of the automobile, numerous post-WW II government programs such as the Interstate Highway System encouraged suburban sprawl. Towns and cities adjacent to tourist attractions, known as gateway communities, face unique problems caused by sprawl. Gettysburg, Pennsylvania, is an example of a gateway community as it includes the Gettysburg National Military Park. Two study sites, portions of Steinwehr Avenue and York Street, were studied to analyze the effects of sprawl in Gettysburg. The sites were analyzed using ArcGIS, data compiled from historic phonebooks, and discussions with local business owners. Development along York Street exemplifies an auto-centric culture with many regional and national chain establishments set back from the road. Steinwehr Avenue represents a walkable community comprising on-street parking, sidewalks, and local “mom-and-pop” establishments. Trends associated with categories of businesses varied between the two sites and revealed different development patterns. We predict that that York Street will continue to sprawl while Steinwehr Avenue development will be limited due to its close proximity to the battlefield

Direct Determinations of the Redshift Behavior of the Pressure, Energy Density, and Equation of State of the Dark Energy and the Acceleration of the Universe

One of the goals of current cosmological studies is the determination of the expansion and acceleration rates of the universe as functions of redshift, and the determination of the properties of the dark energy that can explain these observations. Here the expansion and acceleration rates are determined directly from the data, without the need for the specification of a theory of gravity, and without adopting an a priori parameterization of the form or redshift evolution of the dark energy. We use the latest set of distances to SN standard candles from Riess et al. (2004), supplemented by data on radio galaxy standard ruler sizes, as described by Daly and Djorgovski (2003, 2004). We find that the universe transitions from acceleration to deceleration at a redshift of about 0.4. The standard "concordance model" provides a reasonably good fit to the dimensionless expansion rate as a function of redshift, though it fits the dimensionless acceleration rate as a function of redshift less well. The expansion and acceleration rates are then combined with a theory of gravity to determine the pressure, energy density, and equation of state of the dark energy as functions of redshift. Adopting General Relativity as the correct theory of gravity, the redshift trends for the pressure, energy density, and equation of state of the dark energy out to redshifts of about one are determined, and are found to be generally consistent with the concordance model.Comment: 8 pages, 5 figures. Invited presentation at Coral Gables 200

Aggregate real wages: macro fluctuations and micro drivers

Using data from the Current Population Survey from 1980 through 2010 we examine what drives variation and cyclicality in the growth rate of real wages over time. We employ a novel decomposition technique that allows us to divide the time series for median weekly earnings growth into the part associated with the wage growth of persons employed at the beginning and end of the period (the wage growth effect) and the part associated with changes in the composition of earners (the composition effect). The relative importance of these two effects varies widely over the business cycle. When the labor market is tight job switchers get high wage increases, making them account for half of the variation in median weekly earnings growth over our sample. Their wage growth, as well as that of job-stayers, is procyclical. During labor market downturns, this procyclicality is largely offset by the change in the composition of the workforce, leading aggregate real wages to be almost noncyclical. Most of this composition effect works through the part-time employment margin. Remarkably, the unemployment margin neither accounts for much of the variation nor for much of the cyclicality of median weekly earnings growth.Wages ; Labor market

Stochastic modeling of soil salinity

A minimalist stochastic model of primary soil salinity is proposed, in which the rate of soil salinization is determined by the balance between dry and wet salt deposition and the intermittent leaching events caused by rainfall events. The long term probability density functions of salt mass and concentration are found by reducing the coupled soil moisture and salt mass balance equation to a single stochastic differential equation driven by multiplicative Poisson noise. The novel analytical solutions provide insight on the interplay of the main soil, plant and climate parameters responsible for long-term soil salinization. In particular, they show the existence of two distinct regimes, one where the mean salt mass remains nearly constant (or decreases) with increasing rainfall frequency, and another where mean salt content increases markedly with increasing rainfall frequency. As a result, relatively small reductions of rainfall in drier climates may entail dramatic shifts in long-term soil salinization trends, with significant consequences e.g. for climate change impacts on rain-fed agricultur

10 Best Practices for Effective Program Management

James Madison University College of Business Professor, Paula Daly, reflects on her experiences teaching the Center for International Stabilization and Recovery’s Senior Managers’ Course in ERW and Mine Action and provides a list of best practices for senior mine action managers

The Properties and Gaseous Environments of Powerful Classical Double Radio Galaxies

The properties of a sample of 31 very powerful classical double radio galaxies with redshifts between zero and 1.8 are studied. The source velocities, beam powers, ambient gas densities, total lifetimes, and total outflow energies are presented and discussed. The rate of growth of each side of each source were obtained using a spectral aging analysis. The beam power and ambient gas density were obtained by applying the strong shock jump conditions to the ends of each side of the source. The total outflow lifetime was obtained by applying the power-law relationship between the beam power and the total source lifetime derived elsewhere for sources of this type, and the total outflow energy was obtained by combining the beam power and the total source lifetime. Composite profiles were constructed by combining results obtained from each side of each source. The composite profiles indicate that the ambient gas density falls with distance from the central engine. The source velocities, beam powers, total lifetimes, and total energies seem to be independent of radio source size. This is consistent with the standard model in which each source grows at a roughly constant rate during which time the central engine puts out a roughly constant beam power. The fact that the total source lifetimes and energies are independent of radio source size indicates that the sources are being sampled at random times during their lifetimes.Comment: 7 pages, 5 figures, to appear in "Extragalactic Jets: Theory and Observation from Radio to Gamma Ray", eds. T. A. Rector and D. S. De Young, ASP conference series, Replaced version has minor textual correction

Effects of a multi-component exercise program and calcium–vitamin-D3-fortified milk on bone mineral density in older men : a randomised controlled trial

Summary We examined the independent and combined effects of a multi-component exercise program and calcium&ndash;vitamin-D3-fortified milk on bone mineral density (BMD) in older men. Exercise resulted in a 1.8% net gain in femoral neck BMD, but additional calcium&ndash;vitamin D3 did not enhance the response in this group of older well-nourished men.Introduction This 12-month randomised controlled trial assessed whether calcium&ndash;vitamin-D3-fortified milk could enhance the effects of a multi-component exercise program on BMD in older men.Methods Men (n&thinsp; =&thinsp;180) aged 50&ndash;79 years were randomised into: (1) exercise + fortified milk; (2) exercise; (3) fortified milk; or (4) controls. Exercise consisted of high intensity progressive resistance training with weight-bearing impact exercise. Men assigned to fortified milk consumed 400 mL/day of low fat milk providing an additional 1,000 mg/day calcium and 800 IU/day vitamin D3. Femoral neck (FN), total hip, lumbar spine and trochanter BMD and body composition (DXA), muscle strength 25-hydroxyvitamin D and parathyroid hormone (PTH) were assessed.Results There were no exercise-by-fortified milk interactions at any skeletal site. Exercise resulted in a 1.8% net gain in FN BMD relative to no-exercise (p&thinsp;&lt;&thinsp;0.001); lean mass (0.6 kg, p&thinsp;&lt;&thinsp;0.05) and muscle strength (20&ndash;52%, p&thinsp;&lt;&thinsp;0.001) also increased in response to exercise. For lumbar spine BMD, there was a net 1.4&ndash;1.5% increase in all treatment groups relative to controls (all p&thinsp;&lt;&thinsp;0.01). There were no main effects of fortified milk at any skeletal site.Conclusion A multi-component community-based exercise program was effective for increasing FN BMD in older men, but additional calcium&ndash;vitamin D3 did not enhance the osteogenic response.<br /