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Hydraulic fracturing is one of the industrial processes behind the surging natural gas output in the United States. This technology inadvertently creates an engineered microbial ecosystem thousands of meters below Earth's surface. Here, we used laboratory reactors to perform manipulations of persisting shale microbial communities that are currently not feasible in field scenarios. Metaproteomic and metabolite findings from the laboratory were then corroborated using regression-based modeling performed on metagenomic and metabolite data from more than 40 produced fluids from five hydraulically fractured shale wells. Collectively, our findings show that Halanaerobium, Geotoga, and Methanohalophilus strain abundances predict a significant fraction of nitrogen and carbon metabolites in the field. Our laboratory findings also exposed cryptic predatory, cooperative, and competitive interactions that impact microorganisms across fractured shales. Scaling these results from the laboratory to the field identified mechanisms underpinning biogeochemical reactions, yielding knowledge that can be harnessed to potentially increase energy yields and inform management practices in hydraulically fractured shales.

Recent initiatives in geosciences education have focused on interactive and inquiry-based learning experiences both inside and outside of the classroom. While the concept is sound, examples and datasets seldom focus on opportunities to which the students can immediately relate. Herein we show how a university tradition has been transformed into an interactive geosciences learning opportunity for the university community. Each year during the third week of November, thousands of university students jump into an artificial pond on campus in support of the annual football rivalry game. An undergraduate student research initiative documenting the water quality of the pond before, during, and after the event clearly documents how humans can affect their environment. Use of the resulting dataset in the classroom for an entry-level geoscience laboratory exercise on water contamination has sparked student interest in the effects of anthropogenic activities on water quality and has mobilized subsequent studies to test additional hypotheses. Changes in students' attitudes on water quality were documented by significant differences in administered pre- and postexercise surveys with five-point Likert-type items, while subsequent interest in the dataset from both the university and the surrounding communities has provided additional audiences for engagement on local water contamination issues. Inclusion of the dataset into laboratory exercises is intended to lead to future research questions and promote independent research initiatives.

Various aspects of electrospun fibers prepared from terpolymer of tetrafluoroethylene (TFE), hexafluoropropylene (HFP), and vinylidene fluoride (VDF) (THV)/acetone solutions at two applied voltages, THV/acetone solutions having Texas montmorillonite with two ratios, and THV/ethyl acetate solutions using two needle sizes are described. Fibers from THV/acetone and THV/ethyl acetate solutions showed shallow indentations and pores, respectively. The clay, functioning as electrospinning agent, did not influence the fiber morphology, but yielded narrower fiber diameter distribution and the thinnest fibers. Heterogeneous fiber diameter distribution and increase in the fiber diameters were observed by lowering the voltage for fibers of THV/acetone solutions. Fibers from THV/ethyl acetate solutions had the largest diameter and the broadest diameter distribution. Electrospun THV fibers having both hydrophobic characteristics with nearly 140° water contact angles and oleophilic properties with oil contact angles less than 45° might have applications in areas such as water/oil separation.

Examines effects of the Supreme Court decision, "Regents of the University of California V. Bakke" on Black and Hispanic enrollment in medical and law schools. Uses time-series analysis on aggregate enrollment trends between 1968 and 1987. Finds decision had little impact but notes decline in these applications beginning in 1984. (NL)