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The need for sustainable agricultural practices to meet the food, feed, and fuel demands of a growing global population while reducing detrimental environmental impacts has driven research in multi-faceted approaches to agricultural sustainability. Perennial cropping systems and microbial biofertilizer supplements are two emerging strategies to increase agricultural sustainability that are studied in tandem for the first time in this study. During the establishment phase of a perennial switchgrass stand in SW Montana, USA, we supplemented synthetic fertilization with a nitrogen-fixing cyanobacterial biofertilizer (CBF) and were able to maintain aboveground crop productivity in comparison to a synthetic only (urea) fertilizer treatment. Soil chemical analysis conducted at the end of the growing season revealed that late-season nitrogen availability in CBF-supplemented field plots increased relative to urea-only plots. High-throughput sequencing of bacterial/archaeal and fungal communities suggested fine-scale responses of the microbial community and sensitivity to fertilization among arbuscular mycorrhizal fungi, Planctomycetes, Proteobacteria, and Actinobacteria. Given their critical role in plant productivity and soil nutrient cycling, soil microbiome monitoring is vital to understand the impacts of implementation of alternative agricultural practices on soil health.

A study was conducted to investigate some basic power communication factors among American male and female executives in middle and top level management. Variables of primary interest were perceptions of personal power and communication effectiveness within the organization, and some power communication techniques employed by the two genders to establish images of authority and/or influence in professional settings. Five hundred randomly selected top and middle management executives living in the United States were mailed questionnaire. Of the 210 responses, 72 surveys were returned by the United States Postal Service as undeliverable, and 113 executives reported to be retired, deceased, or otherwise ineligible. The resulting return rate, accounting for those subjects designated as ineligible or unreachable, was 70%. The results of this study suggest that male and female administrators perceive differing levels of organizational power, but employ very similar power communication styles and report no significant difference in perceptions of personal communication effectiveness in the organizational settings. Periodic follow up studies similar to this one would be helpful as women and men gain more experience working with one another in an administrative function. (DF)

RNA interference (RNAi) is a naturally occurring gene silencing mechanism conserved across organisms with a clearly defined cell nucleus (eukaryotes). Gene silencing by RNAi through the degradation of a target messenger RNA (mRNA) has historically been used as a research tool to study the function of genes. Over the past two decades, silencing of vital genes through RNAi has been explored for agricultural applications, including managing plant insect pests and pathogens, improving plant agronomic traits, and increasing consumer desirability of food. Using RNAi for crop protection is especially attractive because of its high specificity, which minimizes unintended effects on non-target organisms and improves the safety profile of RNAi products. This paper describes how RNAi functions, its current applications in agriculture, the current regulatory views of RNAi-based pesticides, and concludes with a discussion of current challenges for the commercial application of RNAi in agriculture. The content presented is intended to serve as a resource for regulatory agencies, policy and lawmakers, private and public institutions, and the general public to inform regulatory assessments and consumer choice decisions. [ABSTRACT FROM AUTHOR]

The first author in recent work with D. Gay developed the notion of a Morse structure on an open book as a tool for studying closed contact 3-manifolds. We extend the notion of Morse structure to extendable partial open books in order to study contact 3-manifolds with convex boundary., Comment: 19 pages, 9 figures