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In this paper, the concept of toric difference varieties is defined and four equivalent descriptions for toric difference varieties are presented in terms of difference rational parametrization, difference coordinate rings, toric difference ideals, and group actions by difference tori. Connections between toric difference varieties and affine N[x]-semimodules are established by proving the corr...

*Extension Crop Specialist, Professor of Forage Genetics and Research Associate in Forages, respectively, Department of Plant & Soil Sciences, Montana State University, Bozeman, MT 59717 Alfalfa—the most productive and most widely adapted forage species—is indeed “Queen of the Forages.” A grower’s initial decision to produce alfalfa and subsequent choice of varieties have long-term consequences...

Let fa,b(z, z̄) = z a1+b1 1 z̄ b1 1 + · · ·+z an+bn n z̄ bn n be a polar weighted homogeneous polynomial with aj > 0, bj ≥ 0, j = 1, . . . , n and let fa(z) = z1 1 + · · ·+z an n be the associated weighted homogeneous polynomial. Consider the corresponding link variety Ka,b = f −1 a,b (0) ∩ S2n−1 and Ka = f−1 a (0) ∩ S2n−1. Ruas-Seade-Verjovsky [4] proved that the Milnor fibrations of fa,b and fa ...

This paper considers the implications for Supply Chain Management (SCM) from the development of the Internet of Things (IoT) or Internet Connected Objects (ICO). We focus on opportunities and challenges stemming from consumption data that comes from ICO, and on how this data can be mapped onto strategic choices of product variety. We develop a simple analytical framework that illustrates the un...

This paper considers vertical relations between an upstream manufacturer and a downstream retailer that can independently obtain a low-quality, discount substitute. The analysis reveals that under full information the retailer offers both varieties only if it is optimal to do so under vertical integration. However, when the retailer is privately informed about demand, then the retailer will off...

BACKGROUND In Canada, graduating medical students consider many factors, including geographic, social, and academic, when ranking residency programs through the Canadian Residency Matching Service (CaRMS). The relative significance of these factors is poorly studied in Canada. It is also unknown how students differentiate between their top program choices. This survey study addresses the influe...

objective: the aim of this study was to investigate the current factors affecting the choice of ‎psychiatry as a specialty and to detect the main factors in their choice.‎ method: this descriptive study included 75 first year psychiatry residents in the academic year of ‎‎2014/2015. a likert-type anonymous questionnaire consisting of academic and ‎demographic data with 43 questions, which evalu...

Aspects of the environment, including the social environment, can contribute to intrapopulation variation in mating preferences. One example of the effect of social environment on mate preferences is mate choice copying; however, other types of socially influenced (nonindependent) choice might exist. We develop a list of such alternatives based on possible physiological or psychological mechani...

Multi-view Geometry is reviewed from an Algebraic Geometry perspective and multi-focal tensors are constructed as equivariant projections of the Grassmannian. A connection to the principal minor assignment problem is made by considering several flatlander cameras. The ideal of the quadrifocal variety is computed up to degree 6 using the representations of GL(3) in the polynomial ring on the spa...