6,714 research outputs found

    PRODUCTION DECISIONS WITH UNCERTAIN MARKETS: THE CASE OF BT CORN

    Get PDF
    The effect of marketing uncertainty due to consumer opposition over genetically modified (GM) grain is modeled in the context of a producer's decision to plant GM. The model shows that a tendency to plant less GM acreage and obtain premium prices for Non-GM grain is tempered by increased price risk.Crop Production/Industries,

    The Interplanetary Network Supplement to the BeppoSAX Gamma-Ray Burst Catalogs

    Get PDF
    Between 1996 July and 2002 April, one or more spacecraft of the interplanetary network detected 787 cosmic gamma-ray bursts that were also detected by the Gamma-Ray Burst Monitor and/or Wide-Field X-Ray Camera experiments aboard the BeppoSAX spacecraft. During this period, the network consisted of up to six spacecraft, and using triangulation, the localizations of 475 bursts were obtained. We present the localization data for these events.Comment: 89 pages, 3 figures. Submitted to the Astrophysical Journal Supplement Serie

    No Evidence for Gamma-Ray Burst/Abell Cluster or Gamma- Ray Burst/Radio-Quiet Quasar Correlations

    Get PDF
    We examine the recent claims that cosmic gamma-ray bursts are associated with either radio-quiet quasars or Abell clusters. These associations were based on positional coincidences between cataloged quasars or Abell clusters, and selected events from the BATSE 3B catalog of gamma-ray bursts. We use a larger sample of gamma-ray bursts with more accurate positions, obtained by the 3rd Interplanetary Network, to re-evaluate these possible associations. We find no evidence for either.Comment: Accepted for publication in the Astrophysical Journa

    The mass of the black hole in GRS 1915+105: new constraints from IR spectroscopy

    Get PDF
    GRS 1915+105 has the largest mass function of any Galactic black hole system, although the error is relatively large. Here we present spectroscopic analysis of medium-resolution IR VLT archival data of GRS 1915+105 in the K-band. We find an updated ephemeris, and report on attempts to improve the mass function by a refinement of the radial velocity estimate. We show that the spectra are significantly affected by the presence of phase-dependent CO bandhead emission, possibly originating from the accretion disc: we discuss the impact this has on efforts to better constrain the black hole mass. We report on a possible way to measure the radial velocity utilising apparent H-band atomic absorption features and also discuss the general uncertainty of the system parameters of this well-studied objectComment: 7 pages, 7 figures. Accepted for publication in Monthly Notices of the Royal Astronomical Society Main Journa

    WHAT IS THE VALUE OF BT CORN?

    Get PDF
    A common perception is that the value of Bt corn arises from two components-Bt corn increases expected profit and reduces profit variability. This perception encourages farmers and the policy makers to add a risk benefit to estimates of the value of Bt corn to account for the variability reduction. However, a conceptual model generates a useful decomposition of the value of Bt corn and a condition determining the impact of Bt corn on profit variability. An empirical model finds that Bt corn increases profit variability and thus decreases the value of Bt corn by 10-25% depending on risk preferences.Crop Production/Industries,

    Adoption of Best Management Practices to Control Weed Resistance By Cotton, Corn, and Soybean Growers

    Get PDF
    This study examined adoption of ten best management practices (BMPs) to control weed resistance to herbicides. Using data from a survey of 1,205 U.S. cotton, corn, and soybean growers, count data models were estimated to explain the total number of practices frequently adopted. Ordered probit regressions were used to explain the frequency of individual BMP adoption. Growers practicing a greater number of BMPs frequently (a) had more education, but less farming experience; (b) grew cotton, (c) expected higher yields relative to the county average; and (d) farmed in counties with a lower coefficient of variation (CV) for yield of their primary crop. Yield expectations and variability were significant predictors of the frequency of adoption of individual BMPs. Most growers frequently adopted the same seven BMPs. Extension efforts may be more effective if they target a minority of growers and the three practices with low adoption rates. Counties with a high yield CV would be areas to look for low BMP adoption.weeds, herbicide, resistance management, corn, cotton, soybeans, adoption, Crop Production/Industries, Farm Management, Production Economics, Research and Development/Tech Change/Emerging Technologies, Q12, Q16,

    Valuing the Roundup ReadyÂź Soybean Weed Management Program

    Get PDF
    This study examines soybean grower adoption of the Roundup ReadyÂź (RR) weed management program with and without a residual herbicide application, and grower concerns regarding weed resistance to herbicides using telephone survey data from of 357 growers in 2007. It also estimates the pecuniary and non-pecuniary benefits enjoyed by growers from their RR program. The results indicate that soybean growers planned to treat 29 percent of their RR acres with a residual herbicide in 2008. More than half (53%) of the growers survey were concerned about weed resistance. The estimated expected benefit of the RR program in 2008 was 10.17peracre,whichtranslatesintoabout10.17 per acre, which translates into about 727 million with 75.7 million acres of soybean in the U.S. in 2008. The estimated value per acre of the RR program with and without a residual was 8.78and8.78 and 12.83. The estimates also suggest that if growers were not using residual herbicides with the RR program, their benefits would be 28.4% lower. Alternatively, if all growers were required to use residual herbicides on their RR acres, the value of the RR program would be 46% lower. Simply increasing grower weed resistance concerns could increase residual herbicide use on RR acres by up to 7%. The same increase in residual herbicide use could be accomplished by decreasing the cost of residual herbicide applications on RR acres by $0.81 per acre.Roundup Ready, Soybean, Glyphosate, Weed Resistance, Benefits, Crop Production/Industries, Demand and Price Analysis, Farm Management, Research and Development/Tech Change/Emerging Technologies,
    • 

    corecore