Publications by authors named "Stambaugh M"

Pinus species dominate fire-prone ecosystems throughout the northern hemisphere. Their litter drive fires that control plant community flammability and multiple ecological processes. To better understand the patterns and mechanisms of pine flammability, we measured leaf characteristics (needle length and thickness) and conducted combustion experiments on litter from 31 species.

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The concept of a portable, wearable system for repetitive transcranial stimulation (rTMS) has attracted widespread attention, but significant power and field intensity requirements remain a key challenge. Here, a circuit topology is described that significantly increases induced electric field intensity over that attainable with similar current levels and coils in conventional rTMS systems. The resultant electric field is essentially monophasic, and has a controllable, shortened duration.

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Globally increasing wildfires have been attributed to anthropogenic climate change. However, providing decision makers with a clear understanding of how future planetary warming could affect fire regimes is complicated by confounding land use factors that influence wildfire and by uncertainty associated with model simulations of climate change. We use an ensemble of statistically downscaled Global Climate Models in combination with the Physical Chemistry Fire Frequency Model (PC2FM) to project changing potential fire probabilities in the conterminous United States for two scenarios representing lower (RCP 4.

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Acoustofluidics has promised to enable lab-on-a-chip and point-of-care devices in ways difficult to achieve using other methods. Piezoelectric ultrasonic transducers-as small as the chips they actuate-provide rapid fluid and suspended object transport. Acoustofluidic lab-on-chip devices offer a vast range of benefits in early disease identification and noninvasive drug delivery.

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This paper describes the design and testing of a compact, battery-powered repetitive Transcranial Magnetic Stimulation (rTMS) prototype. This device generates a 10 Hz magnetic pulse train with peak flux density of 100 mT at 2 cm distance. Circuit component design, including the inductor, switched LC resonator, and boost converter, are discussed in the context of weight and size reduction, and performance optimization.

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The COVID-19 pandemic has produced critical shortages of ventilators worldwide. There is an unmet need for rapidly deployable, emergency-use ventilators with sufficient functionality to manage COVID-19 patients with severe acute respiratory distress syndrome. Here, we show the development and validation of a simple, portable and low-cost ventilator that may be rapidly manufactured with minimal susceptibility to supply chain disruptions.

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The effects of climate on wildland fire confronts society across a range of different ecosystems. Water and temperature affect the combustion dynamics, irrespective of whether those are associated with carbon fueled motors or ecosystems, but through different chemical, physical, and biological processes. We use an ecosystem combustion equation developed with the physical chemistry of atmospheric variables to estimate and simulate fire probability and mean fire interval (MFI).

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To test tree growth sensitivity to temperature under different ambient CO concentrations, we determined stem radial growth rates as they relate to variation in temperature during the last deglacial period, and compare these to modern tree growth rates as they relate to spatial variation in temperature across the modern species distributional range. Paleo oaks were sampled from Northern Missouri, USA and compared to a pollen-based, high-resolution paleo temperature reconstruction from Northern Illinois, USA. Growth data were from 53 paleo bur oak log cross sections collected in Missouri.

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Rising atmospheric [CO2 ], ca , is expected to affect stomatal regulation of leaf gas-exchange of woody plants, thus influencing energy fluxes as well as carbon (C), water, and nutrient cycling of forests. Researchers have proposed various strategies for stomatal regulation of leaf gas-exchange that include maintaining a constant leaf internal [CO2 ], ci , a constant drawdown in CO2 (ca  - ci ), and a constant ci /ca . These strategies can result in drastically different consequences for leaf gas-exchange.

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Thirty patients with cancer pain completed a double-blind crossover study comparing controlled-release (CR) and immediate-release (IR) oxycodone. In open-label titration (2 to 21 days), these patients were stabilized on IR oxycodone qid. They were then randomized to double-blind treatment with CR oxycodone q12h or IR oxycodone qid for 3 to 7 days followed by crossover at the same daily dose.

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Dyshidrotic eczema is a chronic, enigmatic condition that usually affects the hands and feet. Modern-technique radiation therapy using megavoltage equipment for the treatment of dyshidrotic eczema has not been described in the literature before. A dramatic clinical response to low-dose external beam radiation therapy was observed in a patient refractory to multiple forms of topical and systemic agents.

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This is a preliminary report of five patients diagnosed with locally advanced nonresectable pancreatic cancer who achieved improved quality of life, delay of local progression, and reduction of biomarker CA 19-9 after infusion of colloidal phosphorus 32 (32P) and administration of combined chemoradiotherapy. A phase II trial using intratumoral colloidal 32P delivery for nonresectable pancreatic cancer without metastases is in progress. Patients initially were given infusions of decadron followed by macroaggregated albumin and 30 mCi colloidal 32P to the interstitial space of the tumor by two infusions 1 week apart.

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Univalent fragments of gamma-globulin preparations from four individual rabbits were fractionated and the amino acid compositions of end fractions were compared. For amino acids with uncharged side chains, differences were consistently less than one residue per fragment of molecular weight 50,000. There were differences in the content of amino acids, other than glutamic acid, with charged side chains; these were in the direction expected on the basis of relative strength of adherence to carboxymethyl cellulose and electrophoretic mobility.

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