Temporal Trends in the Geochemistry and Petrology of the 1980 Mount St. Helens Pyroclastic Flow Deposits

Petrographic and geochemical analyses were performed on pumice from the May 18, June 12, July 22, August 7, and October 16-18 pyroclastic flow deposits. The pumice is dacitic and contains, in order of decreasing abundance, the minerals plagioclase An30-57, hypersthene, hornblende, magnetite-illmenite, ± augite, ± apatite, in a groundmass of highly vesiculated glass and plagioclase microlites. Vesiculation occurred over a period of about one second, but at times during the eruption probably within a zone in the vent rather than at the atmosphere-magma interface. An increase with time in the crystal to glass ratio indicates continued cooling of the magma. Resorption or recrystallization of hornblende in younger flows indicates degassing by loss of H2O. Barring new intrusion of magma, these textural trends suggest that less explosive eruptions might be expected in the future. Using inductively coupled plasma spectroscopy, elemental oxide abundances were determined for Si, Al, Ti, Fe, Mn, Ca, Mg, K, Na, and P; and trace element abundances were determined for Ba, Cr, Cu, La, Nb, Sc, Sr, V, Y, Zn, and Zr. Temporal trends in major and minor element abundances show that Si02 decreases, while FeO (total), CaO, MgO, Ti02, and MnO increase. Temporal trends in trace element abundances show an increase in Cr, Cu, Sc, and V with a decrease in Ba. These trends are toward a more andesitic composition. These data are consistent with the hypothesis that orogenic calk-alkaline rocks are formed by a subcrustal two stage melting process

Natural Selection on Thermal Performance in a Novel Thermal Environment

Tropical ectotherms are thought to be especially vulnerable to climate change because they are adapted to relatively stable temperature regimes, such that even small increases in environmental temperature may lead to large decreases in physiological performance. One way in which tropical organisms may mitigate the detrimental effects of warming is through evolutionary change in thermal physiology. The speed and magnitude of this response depend, in part, on the strength of climate-driven selection. However, many ectotherms use behavioral adjustments to maintain preferred body temperatures in the face of environmental variation. These behaviors may shelter individuals from natural selection, preventing evolutionary adaptation to changing conditions. Here, we mimic the effects of climate change by experimentally transplanting a population of Anolis sagrei lizards to a novel thermal environment. Transplanted lizards experienced warmer and more thermally variable conditions, which resulted in strong directional selection on thermal performance traits. These same traits were not under selection in a reference population studied in a less thermally stressful environment. Our results indicate that climate change can exert strong natural selection on tropical ectotherms, despite their ability to thermoregulate behaviorally. To the extent that thermal performance traits are heritable, populations may be capable of rapid adaptation to anthropogenic warming

Ohio Livestock Waste Management Guide

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UNLV New Horizons Band & UNLV Community Concert Band

Program listing performers and works performed

FRUIT: Faithfully Reflecting Updated Information in Text

Textual knowledge bases such as Wikipedia require considerable effort to keep up to date and consistent. While automated writing assistants could potentially ease this burden, the problem of suggesting edits grounded in external knowledge has been under-explored. In this paper, we introduce the novel generation task of *faithfully reflecting updated information in text* (FRUIT) where the goal is to update an existing article given new evidence. We release the FRUIT-WIKI dataset, a collection of over 170K distantly supervised data produced from pairs of Wikipedia snapshots, along with our data generation pipeline and a gold evaluation set of 914 instances whose edits are guaranteed to be supported by the evidence. We provide benchmark results for popular generation systems as well as EDIT5 -- a T5-based approach tailored to editing we introduce that establishes the state of the art. Our analysis shows that developing models that can update articles faithfully requires new capabilities for neural generation models, and opens doors to many new applications.Comment: v2.0, NAACL 202

Cutting Down on Prompts and Parameters: Simple Few-Shot Learning with Language Models

Prompting language models (LMs) with training examples and task descriptions has been seen as critical to recent successes in few-shot learning. In this work, we show that finetuning LMs in the few-shot setting can considerably reduce the need for prompt engineering. In fact, one can use null prompts, prompts that contain neither task-specific templates nor training examples, and achieve competitive accuracy to manually-tuned prompts across a wide range of tasks. While finetuning LMs does introduce new parameters for each downstream task, we show that this memory overhead can be substantially reduced-finetuning only the bias terms can achieve comparable or better accuracy than standard finetuning while only updating 0.1% of the parameters. All in all, we recommend finetuning LMs for few-shot learning as it is more accurate, has relatively stable performance across different prompts, and can be made nearly as efficient as using frozen LMs