34 research outputs found

    Stable Electromyographic Sequence Prediction During Movement Transitions using Temporal Convolutional Networks

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    Transient muscle movements influence the temporal structure of myoelectric signal patterns, often leading to unstable prediction behavior from movement-pattern classification methods. We show that temporal convolutional network sequential models leverage the myoelectric signal's history to discover contextual temporal features that aid in correctly predicting movement intentions, especially during interclass transitions. We demonstrate myoelectric classification using temporal convolutional networks to effect 3 simultaneous hand and wrist degrees-of-freedom in an experiment involving nine human-subjects. Temporal convolutional networks yield significant (p<0.001)(p<0.001) performance improvements over other state-of-the-art methods in terms of both classification accuracy and stability.Comment: 4 pages, 5 figures, accepted for Neural Engineering (NER) 2019 Conferenc

    EC04-183 Chickpea Production in the High Plains

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    Chickpea (Cicer arietinum L.) is an annual grainlegume or “pulse crop” that is used extensively for human consumption. The seed of this plant, when dried, is commonly used in soup. Its primary use in the United States is for salad bars, while in the Middle East and India it is more frequently cooked and blended with rice dishes. Major chickpea producers include India, Pakistan, Mexico, Turkey, Canada, and Australia. Chickpea makes up more than 20 percent of world pulse production, behind dry bean and pea. Currently, the United States imports more than 80 percent of its domestic chickpea needs. Since the 1980s, chickpea production has increased rapidly in the northwestern United States. Meanwhile, due to agronomic, processing, and marketing constraints, production in the High Plains has been sporadic and often short-lived. During the past few years, the development of new varieties and the potential for chickpea production under dryland and limited irrigation conditions has generated renewed interest among High Plains producers. With this in mind, the purpose of this publication is to provide information to enhance the potential for successful chickpea production

    EC04-183 Chickpea Production in the High Plains

    Get PDF
    Chickpea (Cicer arietinum L.) is an annual grainlegume or “pulse crop” that is used extensively for human consumption. The seed of this plant, when dried, is commonly used in soup. Its primary use in the United States is for salad bars, while in the Middle East and India it is more frequently cooked and blended with rice dishes. Major chickpea producers include India, Pakistan, Mexico, Turkey, Canada, and Australia. Chickpea makes up more than 20 percent of world pulse production, behind dry bean and pea. Currently, the United States imports more than 80 percent of its domestic chickpea needs. Since the 1980s, chickpea production has increased rapidly in the northwestern United States. Meanwhile, due to agronomic, processing, and marketing constraints, production in the High Plains has been sporadic and often short-lived. During the past few years, the development of new varieties and the potential for chickpea production under dryland and limited irrigation conditions has generated renewed interest among High Plains producers. With this in mind, the purpose of this publication is to provide information to enhance the potential for successful chickpea production

    Climatic history of the northeastern United States during the past 3000 years

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    Many ecosystem processes that influence Earth system feedbacks – vegetation growth, water and nutrient cycling, disturbance regimes – are strongly influenced by multidecadal- to millennial-scale climate variations that cannot be directly observed. Paleoclimate records provide information about these variations, forming the basis of our understanding and modeling of them. Fossil pollen records are abundant in the NE US, but cannot simultaneously provide information about paleoclimate and past vegetation in a modeling context because this leads to circular logic. If pollen data are used to constrain past vegetation changes, then the remaining paleoclimate archives in the northeastern US (NE US) are quite limited. Nonetheless, a growing number of diverse reconstructions have been developed but have not yet been examined together. Here we conduct a systematic review, assessment, and comparison of paleotemperature and paleohydrological proxies from the NE US for the last 3000 years. Regional temperature reconstructions (primarily summer) show a long-term cooling trend (1000 BCE–1700 CE) consistent with hemispheric-scale reconstructions, while hydroclimate data show gradually wetter conditions through the present day. Multiple proxies suggest that a prolonged, widespread drought occurred between 550 and 750 CE. Dry conditions are also evident during the Medieval Climate Anomaly, which was warmer and drier than the Little Ice Age and drier than today. There is some evidence for an acceleration of the longer-term wetting trend in the NE US during the past century; coupled with an abrupt shift from decreasing to increasing temperatures in the past century, these changes could have wide-ranging implications for species distributions, ecosystem dynamics, and extreme weather events. More work is needed to gather paleoclimate data in the NE US to make inter-proxy comparisons and to improve estimates of uncertainty in reconstructions

    Oxidative Stress in Cancer

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    Contingent upon concentration, reactive oxygen species (ROS) influence cancer evolution in apparently contradictory ways, either initiating/stimulating tumorigenesis and supporting transformation/proliferation of cancer cells or causing cell death. To accommodate high ROS levels, tumor cells modify sulfur-based metabolism, NADPH generation, and the activity of antioxidant transcription factors. During initiation, genetic changes enable cell survival under high ROS levels by activating antioxidant transcription factors or increasing NADPH via the pentose phosphate pathway (PPP). During progression and metastasis, tumor cells adapt to oxidative stress by increasing NADPH in various ways, including activation of AMPK, the PPP, and reductive glutamine and folate metabolism

    Structural insight into the reaction mechanism and evolution of cytokinin biosynthesis

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    The phytohormone cytokinin regulates plant growth and development. This hormone is also synthesized by some phytopathogenic bacteria, such as Agrobacterium tumefaciens, and is as a key factor in the formation of plant tumors. The rate-limiting step of cytokinin biosynthesis is catalyzed by adenosine phosphate-isopentenyltransferase (IPT). Agrobacterium IPT has a unique substrate specificity that enables it to increase trans-zeatin production by recruiting a metabolic intermediate of the host plant's biosynthetic pathway. Here, we show the crystal structures of Tzs, an IPT from A. tumefaciens, complexed with AMP and a prenyl-donor analogue, dimethylallyl S-thiodiphosphate. The structures reveal that the carbon-nitrogen-based prenylation proceeds by the SN2-reaction mechanism. Site-directed mutagenesis was used to determine the amino acid residues, Asp-173 and His-214, which are responsible for differences in prenyl-donor substrate specificity between plant and bacterial IPTs. IPT and the p loop-containing nucleoside triphosphate hydrolases likely evolved from a common ancestral protein. Despite structural similarities, IPT has evolved a distinct role in which the p loop transfers a prenyl moiety in cytokinin biosynthesis
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