NEGOTIATING CONTRACTS IN THE SPECIALTY CROP INDUSTRY

Crop Production/Industries, Labor and Human Capital,

Small-scale morphologic properties of martian gullies: insights from analysis of HiRISE images

Abstract not available

Clover - A B-mode polarization experiment

Clover is a new instrument being built to detect the B-mode polarization of the CMB. It consists of three telescopes operating at 97, 150, and 220 GHz and will be sited in Chile at the Llano de Chajnantor. Each telescope assembly is scaled to give a constant beam size of 8 arcmin and feeds an array of between 320 and 512 finline-coupled TES bolometers. Here we describe the design, current status and scientific prospects of the instrument.Comment: 11 pages, 6 figures. Proceedings of the Fundamental Physics With CMB workshop, UC Irvine, March 23-25, 2006, to be published in New Astronomy Review

Assessing Variability and Uncertainty in Green Infrastructure Planning Using a High-Resolution Surface-Subsurface Hydrological Model and Site-Monitored Flow Data

Green infrastructure (GI) is increasingly being used in urban areas to supplement the function of conventional drainage infrastructure. GI relies on the “natural” hydrological processes of infiltration and evapotranspiration to treat surface runoff close to where it is generated, alleviating loading on the conventional infrastructure systems. This research addresses growing interest in identification and quantification of uncertainties with distributed, infiltration-based stormwater control measures, retrofitted on private and public properties and in right-of-ways in existing urban areas. We identify four major sources of variability and uncertainty in cumulative performance of systems that rely on extensive implementation of distributed GI: non-additive effects of individual best management practices (BMPs) at the catchment scale; the spatial configuration of fine-scale land use and land cover changes; performance changes due to climate change; and noise levels present in urban flow monitoring programs. Using a three-dimensional coupled surface-subsurface hydrological model of a residential sewershed in Washington DC, we find that prolonged, large-magnitude rain events affect various spatial configurations of GI networks differently. Runoff peaks and volumes can both be influenced by the spatial permutations of infiltration opportunities in addition to the absolute magnitude of treated area. However, the magnitude of the last source of uncertainty—noise levels in urban flow monitoring programs—may be larger than sources of variability associated with spatial changes in fine-scale land use and land cover. Changes associated with climate change– more frequent and larger rainfall events– will likely intensify performance differences between spatial configurations of GI but also increase noise levels in urban flow monitoring programs

Field evaluation of application variables and plant density for bell pepper pest management

Bell peppers are a valuable vegetable crop in the U.S. Management of pepper insects and diseases relies on chemical control options. Because there are relatively few chemical options available for pepper pest management, it is critical to make efficacious application of pesticides. Foliar spray coverage and spray retention in the middle and bottom of bell pepper canopies were compared using fluorescent dyes and food coloring, respectively. Several delivery systems were evaluated, including air-induction and twin-fan nozzles, air-assisted delivery with conventional hydraulic nozzles, and pneumatic atomization nozzles producing electrically charged sprays. Plant spacing between and within rows was evaluated in the second year of the application trial. Travel speeds of 6.4 and 12.9 km h^-1 were also evaluated. Faster travel speeds did not significantly affect spray retention in twin-row canopies. The electrostatic sprayer produced the greatest differences in deposits between the middle and bottom of the canopy. Although there was no more than a 25 cm difference between leaves sampled from the middle and bottom canopy locations, spray retention on foliage in the bottom canopy locations had significantly lower retention than the middle canopy for almost all sprayer types. Despite differences in atomization characteristics, the performance of the twin-fan nozzle and the air-induction nozzle treatments were similar. Air-assisted delivery provided no advantage in the amount of spray retained on the foliage, but it produced more desirable spray quality on foliage and resulted in more spray retained on whole fruit

A \u3cem\u3eMycobacterium ulcerans\u3c/em\u3e Toxin, Mycolactone, Causes Apoptosis in Guinea Pig Ulcers and Tissue Culture Cells

Mycobacterium ulcerans is the causative agent of Buruli ulcer, a tropical ulcerative skin disease. One of the most intriguing aspects of this disease is the presence of extensive tissue damage in the absence of an acute inflammatory response. We recently purified and characterized a macrolide toxin, mycolactone, from M. ulcerans. Injection of this molecule into guinea pig skin reproduced cell death and lack of acute inflammatory response similar to that seen following the injection of viable bacteria. We also showed that mycolactone causes a cytopathic effect on mouse fibroblast L929 cells that is characterized by cytoskeletal rearrangements and growth arrest within 48 h. However, these results could not account for the extensive cell death which occurs in Buruli ulcer. The results presented here demonstrate that L929 and J774 mouse macrophage cells die via apoptosis after 3 to 5 days of exposure to mycolactone. Treatment of cells with a pan-caspase inhibitor can inhibit mycolactone-induced apoptosis. We demonstrate that injection of mycolactone into guinea pig skin results in cell death via apoptosis and that the extent of apoptosis increases as the lesion progresses. These results may help to explain why tissue damage in Buruli ulcer is not accompanied by an acute inflammatory response

Is the EGRET source 3EG J1621+8203 the radio galaxy NGC 6251?

We discuss the nature of the unidentified EGRET source 3EG J1621+8203. In an effort to identify the gamma-ray source, we have examined X-ray images of the field from ROSAT PSPC, ROSAT HRI, and ASCA GIS. Of the several faint X-ray point sources in the error circle of 3EG J1621+8203, most are stars or faint radio sources, unlikely to be counterparts to the EGRET source. The most notable object in the gamma-ray error box is the bright FR I radio galaxy NGC 6251. If 3EG J1621+8203 corresponds to NGC 6251, then it would be the second radio galaxy to be detected in high energy gamma rays, after Cen A, which provided the first clear evidence of the detection above 100 MeV of an AGN with a large-inclination jet. If the detection of more radio galaxies by EGRET has been limited by its threshold sensitivity, there exists the exciting possibility that new high energy gamma-ray instruments, with much higher sensitivity, will detect a larger number of radio galaxies in the future.Comment: 7 pages, 6 figures. Accepted for publication in The Astrophysical Journal, August 2002 issu