APPLICATION OF THE ECONOMIC THRESHOLD FOR INTERSEASONAL PEST CONTROL

We show how an interseasonal pest control problem can be simplified to enable an intraseasonal model to be empirically applied, extending the range of application of the intraseasonal model. Three alternative economic thresholds are compared. The optimal solution requires repeated computations by the farmer to compute the profit maximizing dose, with a corresponding threshold, for each pest infestation. Two alternative decision rules require a single computation by the farmer for the threshold and dosage rate. An empirical illustration shows that, relative to the optimal solution which is computationally burdensome to the farmer, little net revenue is lost by using one of the thresholds based upon a simpler decision rule.Farm Management,

Inspections To Avert Terrorism: Robustness Under Severe Uncertainty

Protecting against terrorist attacks requires making decisions in a world in which attack probabilities are largely unknown. The potential for very large losses encourages a conservative perspective, in particular toward decisions that are robust. But robustness, in the sense of assurance against extreme outcomes, ordinarily is not the only desideratum in uncertain environments. We adopt Yakov Ben-Haim’s (2001b) model of information gap decision making to investigate the problem of inspecting a number of similar targets when one of the targets may be attacked, but with unknown probability. We apply this to a problem of inspecting a sample of incoming shipping containers for a terrorist weapon. While it is always possible to lower the risk of a successful attack by inspecting more vessels, we show that robustness against the failure to guarantee a minimum level of expected utility might not be monotonic. Robustness modeling based on expected utility and incorporating inspection costs yields decision protocols that are a useful alternative to traditional risk analysis.Terrorism, Robustness, Severe Uncertainty, Port Security

ECONOMIC THRESHOLDS UNDER UNCERTAINTY WITH APPLICATION TO CORN NEMATODE MANAGEMENT

An economic threshold of agricultural pest management is derived. Results provide a method for researchers to use in making improved pest control recommendations to farmers without farm level decision-making. An empirical illustration for lesion nematode management in irrigated corn is given and directions for further research are indicated.Crop Production/Industries, Risk and Uncertainty,

INFORMATION VALUE IN WEED MANAGEMENT

Use of the economic threshold to improve the efficiency of preemergent-herbicide treatment decisions is limited by a lack of weed information. An economic model for assessing the expected value of weed information needed to implement a threshold decision rule is developed. Empirical results suggest that early season weed information can have value in cabbage weed management in Massachusetts.Crop Production/Industries,

Do Montana\u27s Sixmile Creek Cobbles Have Nevada Origins? Evidence for Headwaters of the Miocene Bell River Basin

The Miocene Sixmile Creek Formation in Montana contains distinctive river cobbles of coarse-grained sandstone and conglomerate that include small grains of black chert, but the source of these cobbles has not been confirmed. The Paleozoic Diamond Peak Formation of Nevada may be one possible source of these cobbles. It is widespread in central Nevada\u27s mountains but is unlike any bedrock formations found in Montana. If cobbles in the Sixmile Creek Formation were derived from central Nevada, the Miocene river that carried them would have had to have crossed the present positions of the Snake River Plain and the Idaho-Montana Continental Divide. The purpose of our study is to test the hypothesis by examining particularly distinctive cobbles along the proposed Miocene river path. We compared cobbles collected from the Sixmile Creek Formation at locations from Nevada to Great Falls, Montana, and compared these to each other and to samples collected from proposed source rocks at Pequot Summit, Nevada. We measured the percentage of black chert grains in each rock sample, as well as the shapes and size ranges of the chert grains. Our results support the hypothesis of a great Miocene river that flowed through Montana from headwaters as far south as central Nevada (Sears, 2014). This would have been possible in the Miocene because tectonics had not yet formed the Snake River Plain and modern Continental Divide. The river implied by this model would have been a tributary to the pre-ice age Bell River basin of Canada, which rivaled the modern Amazon River basin in scale. This research could lead to new understanding of the paleotopography and paleofluvial systems of the western interior of North America

A hazard model of the probability of medical school dropout in the United Kingdom

From individual level longitudinal data for two entire cohorts of medical students in UK universities, we use multilevel models to analyse the probability that an individual student will drop out of medical school. We find that academic preparedness—both in terms of previous subjects studied and levels of attainment therein—is the major influence on withdrawal by medical students. Additionally, males and more mature students are more likely to withdraw than females or younger students respectively. We find evidence that the factors influencing the decision to transfer course differ from those affecting the decision to drop out for other reasons

Treating tobacco use in patients with incurable malignancies: Should we even start the conversation?

Background: Clinical practice guidelines recommend that all medical providers address tobacco use with patients, as the long-term health benefits of becoming tobacco free are well documented. What happens, though, when a patient has an incurable malignancy and, therefore, will not reap the long-term benefits? Clinical Consideration: Our case study encourages providers to consider the relevance of tobacco use treatment for those with incurable diseases. Discussion: Although long-term benefits will not provide realistic motivation, other equally important rewards (e.g., decreased shortness of breath), a sense of accomplishment shared by patients and family, and the ability to exert control over a behavior can be equally motivating for some patients

Case Study: Use of Electronic Nicotine Delivery Systems (ENDS) By a Pregnant Woman

Introduction: The use of electronic nicotine delivery systems (ENDS) such as electronic cigarettes, vapour cigarettes, and vapour/hookah pens is rapidly increasing. The effectiveness of ENDS for smoking cessation and their safety, particularly amongst pregnant women, is largely unknown. Some women who use tobacco products in pregnancy, such as the one described in this case study, switch to ENDS assuming they are a safer alternative to smoking traditional cigarettes. Many obstetric providers do not screen for ENDS use and may miss an opportunity to counsel their patients about ENDS usage, side effects, or alternatives. Case Description: Motivated by concern for her baby's health, a 28-year-old patient reduced consumption of traditional cigarettes and began using ENDS shortly after learning she was pregnant. Her obstetric team did not screen for ENDS use and was unaware that she had started using ENDS. During the postpartum period, her providers ordered a tobacco cessation consult and the tobacco treatment specialist (TTS) discovered the patient's ENDS use as well as her desire to quit. Conclusions: In the absence of consistent screening by providers and a lack of safety data regarding ENDS use during pregnancy, women are often given little guidance in deciphering the potential risks and benefits of ENDS use. In this case, the patient turned to ENDS because she thought it was safer than smoking tobacco cigarettes and was unaware that there is limited research on ENDS safety. This case highlights the importance of updating clinical screening tools to include ENDS and the need for further research investigating the safety of ENDS use during pregnancy