University of Missouri

About: University of Missouri is a education organization based out in Columbia, Missouri, United States. It is known for research contribution in the topics: Population & Poison control. The organization has 41427 authors who have published 83598 publications receiving 2911437 citations. The organization is also known as: Mizzou & Missouri-Columbia.

Glutamate triggers long-distance, calcium-based plant defense signaling.

Abstract: Animals require rapid, long-range molecular signaling networks to integrate sensing and response throughout their bodies The amino acid glutamate acts as an excitatory neurotransmitter in the vertebrate central nervous system, facilitating long-range information exchange via activation of glutamate receptor channels Similarly, plants sense local signals, such as herbivore attack, and transmit this information throughout the plant body to rapidly activate defense responses in undamaged parts Here we show that glutamate is a wound signal in plants Ion channels of the GLUTAMATE RECEPTOR-LIKE family act as sensors that convert this signal into an increase in intracellular calcium ion concentration that propagates to distant organs, where defense responses are then induced

Accounting for uncertainty in ecological analysis: the strengths and limitations of hierarchical statistical modeling

Abstract: Analyses of ecological data should account for the uncertainty in the process(es) that generated the data. However, accounting for these uncertainties is a difficult task, since ecology is known for its complexity. Measurement and/or process errors are often the only sources of uncertainty modeled when addressing complex ecological problems, yet analyses should also account for uncertainty in sampling design, in model specification, in parameters governing the specified model, and in initial and boundary conditions. Only then can we be confident in the scientific inferences and forecasts made from an analysis. Probability and statistics provide a framework that accounts for multiple sources of uncertainty. Given the complexities of ecological studies, the hierarchical statistical model is an invaluable tool. This approach is not new in ecology, and there are many examples (both Bayesian and non-Bayesian) in the literature illustrating the benefits of this approach. In this article, we provide a baseline for concepts, notation, and methods, from which discussion on hierarchical statistical modeling in ecology can proceed. We have also planted some seeds for discussion and tried to show where the practical difficulties lie. Our thesis is that hierarchical statistical modeling is a powerful way of approaching ecological analysis in the presence of inevitable but quantifiable uncertainties, even if practical issues sometimes require pragmatic compromises.

AUXIN RESPONSE FACTOR1 and AUXIN RESPONSE FACTOR2 regulate senescence and floral organ abscission in Arabidopsis thaliana.

Abstract: In plants, both endogenous mechanisms and environmental signals regulate developmental transitions such as seed germination, induction of flowering, leaf senescence and shedding of senescent organs. Auxin response factors (ARFs) are transcription factors that mediate responses to the plant hormone auxin. We have examined Arabidopsis lines carrying T-DNA insertions in AUXIN RESPONSE FACTOR1 (ARF1) and ARF2 genes. We found that ARF2 promotes transitions between multiple stages of Arabidopsis development. arf2 mutant plants exhibited delays in several processes related to plant aging, including initiation of flowering, rosette leaf senescence, floral organ abscission and silique ripening. ARF2 expression was induced in senescing leaves. ARF2 regulated leaf senescence and floral organ abscission independently of the ethylene and cytokinin response pathways. arf1 mutations enhanced many arf2 phenotypes, indicating that ARF1 acts in a partially redundant manner with ARF2. However, unlike arf2 mutations, an arf1 mutation increased transcription of Aux/IAA genes in Arabidopsis flowers, supporting previous biochemical studies that indicated that ARF1 is a transcriptional repressor. Two other ARF genes, NPH4/ARF7 and ARF19, were also induced by senescence, and mutations in these genes enhanced arf2 phenotypes. NPH4/ARF7 and ARF19 function as transcriptional activators, suggesting that auxin may control senescence in part by activating gene expression.

Sediment in Streams: Sources, Biological Effects, and Control

Abstract: (1997). Sediment in Streams: Sources, Biological Effects, and Control. Transactions of the American Fisheries Society: Vol. 126, No. 6, pp. 1048-1051.

Customer Loyalty to Whom? Managing the Benefits and Risks of Salesperson-Owned Loyalty

Abstract: In a study of 362 buyer–salesperson dyads using triadic data (from buyer, salesperson, and sales manager), the authors examine both a customer's overall loyalty to the selling firm and the customer's loyalty vested specifically in his or her salesperson. They find that only salesperson-owned loyalty, a newly identified construct, directly affects the more tangible seller financial outcomes of sales growth and selling effectiveness, whereas both salesperson-owned loyalty and loyalty to the selling firm increase the customer's willingness to pay a price premium. A longitudinal study verifies that the positive effect of salesperson-owned loyalty on sales growth persists over time. However, because salesperson-owned loyalty simultaneously increases the seller's risk of losing business if the salesperson defects to a competitor, managers need to manage effectively the benefit–risk trade-off. Increasing relationship-enhancing activities and value received by the customer builds both salesperson-owned l...