1,058 research outputs found

    Unanticipated benefit of an outreach program

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    Author Posting. © The Oceanography Society, 2018. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Unanticipated benefit of an outreach program. Oceanography 31(2), (2018): 10, doi: 10.5670/oceanog.2018.221.The National Science Foundation supported six projects that comprised the Climate Change Education Partnership, including the National Net-work for Ocean and Climate Change Interpretation (NNOCCI) for which the Woods Hole Oceanographic Institution (WHOI) is the science partner. The New England Aquarium leads NNOCCI, and the network also includes informal science educators, social and cognitive scientists, and evaluators. The partners work together to improve public awareness of climate change and its impact on the ocean (Spitzer, 2014; Fraser et al., 2015; Anderson, 2016).Financial support was provided by NSF grant DUE-1043405

    Aircraft remote sensing of phytoplankton spatial patterns during the 1989 Joint Global Ocean Flux Study (JGOFS) North Atlantic bloom experiment

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    Mesoscale phytoplankton chlorophyll variability near the Joint Global Ocean Flux study sites along the 20 W meridian at 34 N, 47 N, and 59 N is discussed. The NASA P-3 aircraft and the Airborne Oceanographic Lidar (AOL) system provides remote sensing support for the North Atlantic Bloom Experiment. The principal instrument of the AOL system is the blue-green laser that stimulates fluorescence from photoplankton chlorophyll, the principal photosynthetic pigment. Other instruments on the NASA P-3 aircraft include up- and down-looking spectrometers, PRT-5 for infrared measurements to determine sea surface temperature, and a system to deploy and record AXBTs to measure subsurface temperature structure

    Robust calibration of a universal single-qubit gate set via robust phase estimation

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    An important step in building a quantum computer is calibrating experimentally implemented quantum gates to produce operations that are close to ideal unitaries. The calibration step involves estimating the systematic errors in gates and then using controls to correct the implementation. Quantum process tomography is a standard technique for estimating these errors but is both time consuming (when one wants to learn only a few key parameters) and usually inaccurate without resources such as perfect state preparation and measurement, which might not be available. With the goal of efficiently and accurately estimating specific errors using minimal resources, we develop a parameter estimation technique, which can gauge key systematic parameters (specifically, amplitude and off-resonance errors) in a universal single-qubit gate set with provable robustness and efficiency. In particular, our estimates achieve the optimal efficiency, Heisenberg scaling, and do so without entanglement and entirely within a single-qubit Hilbert space. Our main theorem making this possible is a robust version of the phase estimation procedure of Higgins et al. [B. L. Higgins et al., New J. Phys. 11, 073023 (2009)NJOPFM1367-263010.1088/1367-2630/11/7/073023].United States. Dept. of DefenseUnited States. Army Research Office. Quantum Algorithms ProgramAmerican Society for Engineering Education. National Defense Science and Engineering Graduate Fellowshi

    Fixed-point adiabatic quantum search

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    Fixed-point quantum search algorithms succeed at finding one of M target items among N total items even when the run time of the algorithm is longer than necessary. While the famous Grover's algorithm can search quadratically faster than a classical computer, it lacks the fixed-point property—the fraction of target items must be known precisely to know when to terminate the algorithm. Recently, Yoder, Low, and Chuang [Phys. Rev. Lett. 113, 210501 (2014)] gave an optimal gate-model search algorithm with the fixed-point property. Previously, it had been discovered by Roland and Cerf [Phys. Rev. A 65, 042308 (2002)] that an adiabatic quantum algorithm, operating by continuously varying a Hamiltonian, can reproduce the quadratic speedup of gate-model Grover search. We ask, can an adiabatic algorithm also reproduce the fixed-point property? We show that the answer depends on what interpolation schedule is used, so as in the gate model, there are both fixed-point and non-fixed-point versions of adiabatic search, only some of which attain the quadratic quantum speedup. Guided by geometric intuition on the Bloch sphere, we rigorously justify our claims with an explicit upper bound on the error in the adiabatic approximation. We also show that the fixed-point adiabatic search algorithm can be simulated in the gate model with neither loss of the quadratic Grover speedup nor of the fixed-point property. Finally, we discuss natural uses of fixed-point algorithms such as preparation of a relatively prime state and oblivious amplitude amplification.American Society for Engineering Education. National Defense Science and Engineering Graduate FellowshipMIT-Harvard Center for Ultracold Atoms MIT International Science and Technology InitiativeNational Science Foundation (U.S.) (RQCC Project 1111337)Massachusetts Institute of Technology. Undergraduate Research Opportunities Program (Paul E. Gray Endowed Fund

    The Cost of Dispersal: Predation as a Function of Movement and Site Familiarity in Ruffed Grouse

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    Ecologists often assume that dispersing individuals experience increased predation risk owing to increased exposure to predators while moving. To test the hypothesis that predation risk is a function of movement distance or rate of movement, we used radio-telemetry data collected from 193 ruffed grouse (Bonasa umbellus) during 1996–1999 in southeastern Ohio. Cox’s proportional hazards model was used to examine whether the risk of predation was affected by the rate of movement and site familiarity. We found evidence indicating that increased movement rates may increase the risk of predation for adult birds but not juveniles. We also found juvenile and adult birds inhabiting unfamiliar space were consistently at a much higher risk of predation (three to 7.5 times greater) than those in familiar space. Our results indicate that although movement itself may have some effect on the risk of being preyed upon, moving through unfamiliar space has a much greater effect on risk for ruffed grouse. This supports the hypothesis that increased predation risk may be an important cost of dispersal for birds.This work was funded by the Ohio Department of Natural Resources, Division of Wildlife and supported by the Department of Evolution, Ecology, and Organismal Biology and the Aquatic Ecology Laboratory at the Ohio State University

    Modeling of Turbulent Free Shear Flows

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    The modeling of turbulent free shear flows is crucial to the simulation of many aerospace applications, yet often receives less attention than the modeling of wall boundary layers. Thus, while turbulence model development in general has proceeded very slowly in the past twenty years, progress for free shear flows has been even more so. This paper highlights some of the fundamental issues in modeling free shear flows for propulsion applications, presents a review of past modeling efforts, and identifies areas where further research is needed. Among the topics discussed are differences between planar and axisymmetric flows, development versus self-similar regions, the effect of compressibility and the evolution of compressibility corrections, the effect of temperature on jets, and the significance of turbulent Prandtl and Schmidt numbers for reacting shear flows. Large eddy simulation greatly reduces the amount of empiricism in the physical modeling, but is sensitive to a number of numerical issues. This paper includes an overview of the importance of numerical scheme, mesh resolution, boundary treatment, sub-grid modeling, and filtering in conducting a successful simulation

    Comparative Metabolomics of Early Development of the Parasitic Plants Phelipanche aegyptiaca and Triphysaria versicolor.

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    Parasitic weeds of the family Orobanchaceae attach to the roots of host plants via haustoria capable of drawing nutrients from host vascular tissue. The connection of the haustorium to the host marks a shift in parasite metabolism from autotrophy to at least partial heterotrophy, depending on the level of parasite dependence. Species within the family Orobanchaceae span the spectrum of host nutrient dependency, yet the diversity of parasitic plant metabolism remains poorly understood, particularly during the key metabolic shift surrounding haustorial attachment. Comparative profiling of major metabolites in the obligate holoparasite Phelipanche aegyptiaca and the facultative hemiparasite Triphysaria versicolor before and after attachment to the hosts revealed several metabolic shifts implicating remodeling of energy and amino acid metabolism. After attachment, both parasites showed metabolite profiles that were different from their respective hosts. In P. aegyptiaca, prominent changes in metabolite profiles were also associated with transitioning between different tissue types before and after attachment, with aspartate levels increasing significantly after the attachment. Based on the results from 15N labeling experiments, asparagine and/or aspartate-rich proteins were enriched in host-derived nitrogen in T. versicolor. These results point to the importance of aspartate and/or asparagine in the early stages of attachment in these plant parasites and provide a rationale for targeting aspartate-family amino acid biosynthesis for disrupting the growth of parasitic weeds

    A moving target : matching graduate education with available careers for ocean scientists

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    Author Posting. © The Oceanography Society, 2016. This article is posted here by permission of The Oceanography Society for personal use, not for redistribution. The definitive version was published in Oceanography 29, no. 1 (2016): 22–30, doi:10.5670/oceanog.2016.05.The objective of this paper is to look at past assessments and available data to examine the match (or mismatch) between university curricula and programs available to graduate students in the ocean sciences and the career possibilities available to those students. We conclude there is a need for fundamental change in how we educate graduate students in the ocean sciences. The change should accommodate the interests of students as well as the needs of a changing society; the change should not be constrained by the traditions or resource challenges of the graduate institutions themselves. The limited data we have been able to obtain from schools and employers are consistent with this view: desirable careers for ocean scientists are moving rapidly toward interdisciplinary, collaborative, societally relevant activities, away from traditional academic-research/professorial jobs, but the training available to the students is not keeping pace. We offer some suggestions to mitigate the mismatch. Most importantly, although anecdotes and “gut feelings” abound, the quantitative data backing our conclusions and suggestions are very sparse and barely compelling; we urge better data collection to support curricular revision, perhaps with the involvement of professional societies

    Indiana Center for Brain Rehabilitation, Advanced Imaging, and Neuroscience (ICBRAIN): An IUPUI Signature Center Initiative

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    poster abstractThe Mission of the Indiana Center for Brain Rehabilitation, Advanced Imaging, and Neuroscience (ICBRAIN) is: to develop and disseminate techniques and methodologies for advanced neuroimaging and precision behavioral measurement to evaluate novel rehabilitation interventions for people with acquired brain injury. Traumatic and other types of acquired brain injury (ABI) affect millions of U.S. citizens each year, many of whom experience persistent disabilities. For example, among the estimated 1.4 million civilians who sustain a traumatic brain injury (TBI) each year, 50,000 die and a minimum of 80,000 sustain injuries of sufficient severity to require extended rehabilitation. The current conflicts in Iraq and Afghanistan have increased awareness and mobilized interest in medical treatment and rehabilitation for returning soldiers with TBI (designated as the “signature injury” of these conflicts). A 2008 study by the RAND corporation based on a random sample of 1,965 veterans estimated that, among 1.64 million returning veterans, approximately 320,000 experienced a probable TBI (19%). Over the past decade there has been a notable rise in research activities to address serious gaps in the knowledge base of ABI, including neuroimaging, outcome measurement, and intervention studies to change function. However, brain injury researchers have not yet established solid links between these research agendas. Such links are crucial for moving the evidence base forward to improve treatment outcomes. ICBRAIN will fill this gap in neuroscience by bringing together an interdisciplinary team of clinical researchers to (1) advance basic science and clinical knowledge to the next level of integration, (2) translate the knowledge gained directly into clinical care for improved patient outcomes, and (3) use the newly integrated knowledge to drive the leading edge of future research. ICBRAIN represents a unique collaboration among established clinical rehabilitation and measurement researchers in PM&R and at RHI and established researchers at the IU Center for Neuroimaging
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