Environmental Effects of Applying Composted Organics to New Highway Embankments: Part 2. Water Quality Part 3. Rill Erosion

Control of stormwater runoff and soil erosion on highway construction sites is a concern for state departments of transportation and municipalities. Composted organics are viewed as an alternative approach to improve construction site soils and to reduce runoff and soil erosion. The objective of this study is to evaluate the use of blanket-applied composted organics on rill erosion as compared to soils. Rill erosion was measured on three composted organics applied at 5 and 10 cm depths, a topsoil treatment (15 cm application), and the existing soil (control) on a highway embankment with a three-to-one sideslope (33%). Treatments were tested using rainfall simulation at a target rate of 100 mm/h and simultaneously adding five inflows at the top of the rill on both vegetated and unvegetated plots. Rill erosion on blanket-applied compost treatments was measured, and the usefulness of the shear stress model for predicting rill erosion on compost-treated areas was assessed. Rill erodibilities and critical shear values were calculated for all treatments using the shear stress model that was originally developed for soil. Rill erodibilities were higher on topsoil-treated plots than on control and compost-treated areas. Yard waste had significantly lower rill erodibility than all other compost and soil treatments. There were no significant differences between critical shear values for the composts and soil. Yard waste compost exhibited greater resistance to rill formation than the biosolids and bio-industrial composts or the two soils. Low R2 values for compost erodibility and critical shear suggest that the shear stress model used in this analysis is not well suited for use with composted organics. Detachment caused by flotation of low-density particles, and bridging caused by coarse particles lodging farther down the slope, are believed to be two rill erosion mechanisms in compost that the shear stress model does not adequately address

Examining the Link between Crime and Unemployment: A Time Series Analysis for Canada

We use national and regional Canadian data to analyse the relationship between economic activity (as reflected by the unemployment rate) and crime rates. Given potential aggregation bias, we disaggregate the crime data and look at the relationship between six different types of crimes rates and unemployment rate; we also disaggregate the data by region. We employ an error correction model in our analysis to test for short-run and long-run dynamics. We find no evidence of long-run relationship between crime and unemployment, when we look at both disaggregation by type of crime and disaggregation by region. Lack of evidence of a long-run relationship indicates we have no evidence of the motivation hypothesis. For selected types of property crimes, we find some evidence of a significant negative short-run relationship between crime and unemployment, lending support to the opportunity hypothesis. Inclusion of control variables in the panel analysis does not alter the findings, qualitatively or quantitatively

The JANUS X-Ray Flash Monitor

JANUS is a NASA small explorer class mission which just completed phase A and was intended for a 2013 launch date. The primary science goals of JANUS are to use high redshift (6<z<12) gamma ray bursts and quasars to explore the formation history of the first stars in the early universe and to study contributions to reionization. The X-Ray Flash Monitor (XRFM) and the Near-IR Telescope (NIRT) are the two primary instruments on JANUS. XRFM has been designed to detect bright X-ray flashes (XRFs) and gamma ray bursts (GRBs) in the 1-20 keV energy band over a wide field of view (4 steradians), thus facilitating the detection of z>6 XRFs/GRBs, which can be further studied by other instruments. XRFM would use a coded mask aperture design with hybrid CMOS Si detectors. It would be sensitive to XRFs/GRBs with flux in excess of approximately 240 mCrab. The spacecraft is designed to rapidly slew to source positions following a GRB trigger from XRFM. XRFM instrument design parameters and science goals are presented in this paper.Comment: submitted to Proc. SPIE, Vol. 7435 (2009), 7 pages, 8 figure