Maximin and maximal solutions for linear programming problems with possibilistic uncertainty

We consider linear programming problems with uncertain constraint coefficients described by intervals or, more generally, possi-bility distributions. The uncertainty is given a behavioral interpretation using coherent lower previsions from the theory of imprecise probabilities. We give a meaning to the linear programming problems by reformulating them as decision problems under such imprecise-probabilistic uncer-tainty. We provide expressions for and illustrations of the maximin and maximal solutions of these decision problems and present computational approaches for dealing with them

The effects of cultivar on nodulation, seed yield, and dinitrogen fixation of dry bean (Phaseolus vulgaris L.)

Non-Peer Reviewe

The impact of inoculation on the tripartite association between pulse crops, rhizobia, and arbuscular mycorrhizal fungi

Non-Peer Reviewe

Assessing soil N availability indices - is inorganic N enough?

Non-Peer ReviewedAssessing soil N availability is complicated enormously by the complexity of the N-cycle. Over the years, several methods of estimating potentially available N have been suggested. In an ongoing study, we have been assessing the suitability of a number of these methods for predicting potential crop response to fertilizer N. In particular, we correlated amino-sugar N levels to wheat yield across a variable landscape. This relatively new soil N test appears to be sensitive to changes in organic matter quality as related to landscape position and holds some promise for assessing potentially available N. The results presented here are preliminary

Diet analysis of wintering waterfowl in the Southeastern United States in relation to ecoregion, habitat, and guild

Wintering waterfowl diet has been studied across North America to gain a better understanding of their foraging habits and feeding ecology. There is a need for a better understanding of waterfowl foraging based on ecoregion, guild, and habitats of wintering waterfowl, especially within the Mississippi Flyway. This study investigated the stomach content of wintering waterfowl in the Southeast United States, within the Mississippi Flyway region. The esophagus, proventriculus, and gizzard of each specimen were removed, dried, and sorted for statistical analysis. Multiple two-way ANOVAs were run to test the effects of ecoregion, habitat, and guild on total mass and diet mass in waterfowl. A difference between years was determined so separate analyses were conducted for each year. My results suggest that there was a significant difference in 2014 data for ecoregion by habitat within the Ridge and Valley ecoregion. Total diet composition results suggest that waterfowl consume different food components in each ecoregion. When analyzing guild diet composition, the results suggest that each guild consumes different types of food products, with the dabblers consuming the most agricultural products, divers consuming the most varied diet, and geese consuming the most grasses

The Contribution of Heredity to Clinical Obesity

In order to discuss the contribution of heredity to clinical obesity, we first need to define our terms of reference to give us the common ground that is needed to explore the relationship between heredity, the environment, and clinical obesity. This will also serve to introduce these subjects for later chapters of this volume covering other aspects of the relative contributions of heredity and environment to the final clinical outcome of obesity. The importance of understanding the mechanisms underlying obesity cannot be overstated. Global rates of obesity are rising fast in most countries and the economic implications for maintaining the health care systems of those countries under the increasing burden of comorbidities and ill health are enormous [1]. Defining Heredity Heredity can simply be defined as the transmission of characteristic traits from parent to offspring. In the mid-nineteenth century, Mendel took this idea and by painstaking experimentation was able to formalize it as his two laws of heredity: the law of segregation and the law of independent assortment. The study of the science of heredity is genetics. In the twenty-first century, we now know the molecular basis of the principles of heredity and though our understanding of human genetics is by no means complete, the information that we have on DNA, the human genome sequence, epigenetics, and the environment all inform our understanding of heredity. We should be clear from the outset that using the term heredity does not imply that there is a purely genetic mechanism underlying the transmission of a trait. For many common traits, and for common obesity in particular, the influence of the environment is clearly strong

Impact of in-crop and soil residual herbicides on effective nitrogen fixation in field pea (Pisum sativum L.) and chickpea (Cicer arietinum L.)

Non-Peer ReviewedA three-year project was initiated in 2004 to examine the effects of residual herbicides and registered “in-crop” herbicides, both soil and foliar applied, on N fixation and consequent yield of field peas and chickpeas. Inoculation strategies were examined to determine if inoculant formulation (i.e., peat powder versus granular inoculant) influences the degree to which herbicides can affect N fixation. This research is ongoing and thus all results are considered preliminary. Preliminary results in field pea, suggest that where herbicides had a negative effect on N fixation, the effects occurred at relatively early growth stages (i.e., soon after herbicide application) and were typically overcome at later growth stages. In addition, granular inoculants were associated with increased N fixation as compared to peat powder inoculants, and may have mitigated any negative herbicide effects. Chickpea incurred damage from the herbicides and all treatments had significantly less N fixation than the control. In general, results suggest that N fixation may be compromised if herbicides cause significant plant damage; however, improved weed control associated with herbicide application may counter the negative impact on early N fixation

Management of fertility in the pulse-based cropping systems of western Canada

Non-Peer Reviewe