NONLINEAR MODELS FOR MULTI-FACTOR PLANT NUTRITION EXPERIMENTS

Plant scientists are interested in measuring plant response to quantitative treatment factors, e.g. amount of nutrient applied. Response surface methods are often used for experiments with multiple quantitative factors. However, in many plant nutrition studies, second-order response surface models result in unacceptable lack of fit. This paper explores multi-factor nonlinear models as an alternative. We have developed multi-factor extensions of Mitscherlich and Gompertz models, and fit them to data from experiments conducted at the University of Nebraska-Lincoln Horticulture department. These data are typical of experiments for which conventional response surface models perform poorly. We propose design selection strategies to facilitate economical multi-factor experiments when second-order response surface models are unlikely to fit

Prevalence of Noncardiac Findings in Patients Undergoing Cardiac Magnetic Resonance Imaging

Purpose. We sought to determine the prevalence of clinically significant non-cardiac abnormalities found in pediatric and adult patients undergoing cardiac magnetic resonance imaging (CMRI), and understand the impact of age on it's occurrence. Methods. We retrospectively reviewed all patients undergoing CMRI between May 2004 and July 2007. Findings were considered significant if they required radiographic or clinical follow-up. Results. A total of 408 patients underwent CMRI during the study period. Twenty two (16%) pediatric patients (age < 19 years, n = 135) were found to have a total of 22 non- cardiac abnormalities, 3 of which were clinically significant. Sixty four (23%) adult patients (age > 19 years, n = 273) were found to have a total of 77 non-cardiac abnormalities, 33 of which were clinically significant. The prevalence of clinically significant non-cardiac abnormalities was 2% in the pediatric cohort and 11% in the adult cohort (P = 0.05). Within the adult population, the prevalence of significant non-cardiac abnormalities increased with advancing age (P = 0.05). Conclusions. In a population of unselected patients undergoing CMRI, unanticipated noncardiac abnormalities were frequently seen. A small number of these were significant, with the prevalence increasing with age

The Counterpart Principle of Analogical Support by Structural Similarity

We propose and investigate an Analogy Principle in the context of Unary Inductive Logic based on a notion of support by structural similarity which is often employed to motivate scientific conjectures

Is copyright blind to the visual?

This article argues that, with respect to the copyright protection of works of visual art, the general uneasiness that has always pervaded the relationship between copyright law and concepts of creativity produces three anomalous results. One of these is that copyright lacks much in the way of a central concept of 'visual art' and, to the extent that it embraces any concept of the 'visual', it is rooted in the rhetorical discourse of the Renaissance. This means that copyright is poorly equipped to deal with modern developments in the visual arts. Secondly, the pervasive effect of rhetorical discourse appears to have made it particularly difficult for copyright law to strike a meaningful balance between protecting creativity and permitting its use in further creative works. Thirdly, just when rhetorical discourse might have been useful in identifying the significance and materiality of the unique one-off work of visual art, copyright law chooses to ignore its implications

Strength of Protection for Geographical Indications: Promotion Incentives and Welfare Effects

We address the question of how the strength of protection for geographical indications (GIs) affects the GI industry\u27s promotion incentives, equilibrium market outcomes, and the distribution of welfare. Geographical indication producers engage in informative advertising by associating their true quality premium (relative to a substitute product) with a specific label emphasizing the GI\u27s geographic origin. The extent to which the names/words of the GI label can be used and/or imitated by competing products—which depends on the strength of GI protection—determines how informative the GI promotion messages can be. Consumers’ heterogeneous preferences (vis-à-vis the GI quality premium) are modeled in a vertically differentiated framework. Both the GI industry and the substitute product industry are assumed to be competitive (with free entry). The model is calibrated and solved for alternative parameter values. Results show that producers of the GI and of the lower-quality substitute good have divergent interests: GI producers are better off with full protection, whereas the substitute good\u27s producers prefer intermediate levels of protection (but they never prefer zero protection because they benefit indirectly if the GI producers’ incentives to promote are preserved). For consumers and aggregate welfare, the preferred level of protection depends on the model\u27s parameters, with an intermediate level of protection being optimal in many circumstances

A gaming simulation approach to understanding blue ocean strategy development as a transition from traditional competitive strategy

Blue Ocean Strategy (BOS) has attracted a resurgence of interest following various market discontinuities, including digital disruption, the growth of the sharing economy and the development of ecosystems. BOS is a combination of value innovation and new markets, driving sustained higher performance through specific marketing activities, but it is difficult to conceive and implement. We outline five cases that use various transition paths to BOS through white spaces - with product extensions in the existing market. An important part of this transition are ‘blue ocean droplets’ which drive profitable growth through the transition and then onto a successful deployment of a blue ocean strategy. Blue ocean droplets drive profitable growth - simultaneously increasing volume sales, maintaining/increasing prices and maintaining/decreasing costs. We then use an inductive qualitative approach in a multi-team gaming simulation to examine drivers of firm performance. Higher than average performance is driven by repositioning in white spaces and execution of the three blue ocean droplets. Finally, we discuss implications for firms: execute a number of real options to follow one of several transition paths to a full BOS. This approach involves less downside risk than a full BOS approach, but can still be sustainably profitable, while also breaking the traditional value/cost trade-off

De Jure Determinants of New Firm Formation: How the Pillars of Constitutions Influence Entrepreneurship

This paper provides empirical evidence supporting the view that constitutions may influence the organization of economic activities. Dealing with the issue of the institutional determinants of entrepreneurship, it shows that some of the provisions contained in national constitutions are positively and significantly associated to a standard measure of entrepreneurial dynamics, namely the rate of new business density. Using a novel dataset containing the characteristics of the constitutions enacted in the world and a sample of 115 countries, the paper finds that provisions about the right to conduct/establish a business, the right to strike, consumer protection, protection of trademarks, and education promote higher rates of new firm formation

Questioning cultural narratives of economic development—an investigation of Kitchener-Waterloo

The version of record [Spigel, B. & Bathelt, H. (2019). Questioning cultural narratives of economic development - An investigation of Kitchener-Waterloo. Canadian Geographer, 63(2), 267-283.] is available online at: https://onlinelibrary.wiley.com/doi/abs/10.1111/cag.12512This paper investigates the relationship between culture and economy and scrutinizes cultural narratives of economic development in Kitchener-Waterloo, southern Ontario. It argues for the need to carefully conceptualize the link between culture and economic development to avoid boosting deterministic stereotypes. In the case of Kitchener-Waterloo, a notable hub of high-technology firms and technology development, a link is frequently drawn between the German community and culture and the region’s technology economy and entrepreneurial culture. A social capital analysis, however, reveals that the German ethnic community neither has the strong professional internal ties nor the external social ties to other regional communities that could constitute a lead role in economic development. Rather, the legacy of Kitchener-Waterloo’s ethnic German population has been absorbed into the region’s self-image and creates a feeling of belonging and common reference points for joint social and economic initiatives in the region