167 research outputs found

    Capability of Recombinant Insect Viruses for Environmental Persistence and Transport.

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    Wild-type and recombinant nucleopolyhedroviruses (NPVs) were compared with respect to their capability to produce epizootics in Trichoplusis ni (Hubner) larvae infesting collards in a greenhouse microcosm. Viruses tested were variants of Autographa californica (Speyer) NPV (AcNPV): wild-type virus (AcNPV.WT), AcNPV expressing a scorpion toxin (AcNPV.AaIT), and AcNPV expressing juvenile hormone esterase (AcJHE.SG). Epizootics of AcNPV.WT lasted 8 weeks after a single viral release in the replicated, greenhouse micro-plots. AcJHE.SG epizootics also lasted 8 weeks after viral release, but this virus and AcNPV.AaIT were both out-competed by AcNPV.WT. AcNPV.AaIT was no longer detected in the T. ni population by the fourth week after release. AcNPV.WT also increased to greater numbers in soil than AcNPV.AaIT or AcJHE.SG after 8 weeks. Both AcNPV.WT and AcJHE.SG had random dispersion patterns in soil. The predator Podisus maculiventris (Say), the scavenging fly Sarcophaga bullata (Parker), and scavenging house crickets Acheta domesticus (Linnaeus) were compared for their capability to transport the wild-type and recombinant viruses. All three insects ingested T. ni larvae infected with or killed by each of the three NPVs. Neither the cricket nor the fly preferred T. ni larvae killed by one type of NPV versus the others. The cumulative survival curves for the three non-target organisms (NTO) did not differ significantly whether they ingested AcNPV.WT-infected, recombinant-infected, or uninfected T. ni. Within 5 days after ingesting virus-infected larvae, all three NTO voided \u3e1000X the median lethal dose of each NPV against neonatal Heliothis virescens (Fabricius). All three insects defecated significantly more AcJHE.SG than the other viruses. Prevalence and spread of the three viruses were compared in the greenhouse microcosm in the presence and absence of one or more of the NTO. Podisus maculiventris transported AcNPV.WT and S. bullata transported AcNPV.WT and AcNPV.AaIT. All three viruses were detected outside viral release sites, indicating that host larvae and abiotic agents may have contributed to viral transport. Prevalence and transport of AcNPV.WT were greater than AcNPV.AaIT and AcJHE.SG regardless of whether the NTO carriers were present or absent

    Highlights of Space Weather Services/Capabilities at NASA/GSFC Space Weather Center

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    The importance of space weather has been recognized world-wide. Our society depends increasingly on technological infrastructure, including the power grid as well as satellites used for communication and navigation. Such technologies, however, are vulnerable to space weather effects caused by the Sun's variability. NASA GSFC's Space Weather Center (SWC) (http://science.gsfc.nasa.gov//674/swx services/swx services.html) has developed space weather products/capabilities/services that not only respond to NASA's needs but also address broader interests by leveraging the latest scientific research results and state-of-the-art models hosted at the Community Coordinated Modeling Center (CCMC: http://ccmc.gsfc.nasa.gov). By combining forefront space weather science and models, employing an innovative and configurable dissemination system (iSWA.gsfc.nasa.gov), taking advantage of scientific expertise both in-house and from the broader community as well as fostering and actively participating in multilateral collaborations both nationally and internationally, NASA/GSFC space weather Center, as a sibling organization to CCMC, is poised to address NASA's space weather needs (and needs of various partners) and to help enhancing space weather forecasting capabilities collaboratively. With a large number of state-of-the-art physics-based models running in real-time covering the whole space weather domain, it offers predictive capabilities and a comprehensive view of space weather events throughout the solar system. In this paper, we will provide some highlights of our service products/capabilities. In particular, we will take the 23 January and the 27 January space weather events as examples to illustrate how we can use the iSWA system to track them in the interplanetary space and forecast their impacts

    Explore the future Earth with Wander 2.0: AI chatbot driven by knowledge-base story generation and text-to-image model

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    People always envision the future of earth through science fiction (Sci-fi), so can we create a unique experience of "visiting the future earth" through the lens of artificial intelligence (AI)? We introduce Wander 2.0, an AI chatbot that co-creates sci-fi stories through knowledge-based story generation on daily communication platforms like WeChat and Discord. Using location information from Google Maps, Wander generates narrative travelogues about specific locations (e.g. Paris) through a large-scale language model (LLM). Additionally, using the large-scale text-to-image model (LTGM) Stable Diffusion, Wander transfers future scenes that match both the text description and location photo, facilitating future imagination. The project also includes a real-time visualization of the human-AI collaborations on a future map. Through journeys with visitors from all over the world, Wander demonstrates how AI can serve as a subjective interface linking fiction and reality. Our research shows that multi-modal AI systems have the potential to extend the artistic experience and creative world-building through adaptive and unique content generation for different people. Wander 2.0 is available at http://wander001.com

    Forecasting Propagation and Evolution of CMEs in an Operational Setting: What Has Been Learned

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    One of the major types of solar eruption, coronal mass ejections (CMEs) not only impact space weather, but also can have significant societal consequences. CMEs cause intense geomagnetic storms and drive fast mode shocks that accelerate charged particles, potentially resulting in enhanced radiation levels both in ions and electrons. Human and technological assets in space can be endangered as a result. CMEs are also the major contributor to generating large amplitude Geomagnetically Induced Currents (GICs), which are a source of concern for power grid safety. Due to their space weather significance, forecasting the evolution and impacts of CMEs has become a much desired capability for space weather operations worldwide. Based on our operational experience at Space Weather Research Center at NASA Goddard Space Flight Center (http://swrc.gsfc.nasa.gov), we present here some of the insights gained about accurately predicting CME impacts, particularly in relation to space weather operations. These include: 1. The need to maximize information to get an accurate handle of three-dimensional (3-D) CME kinetic parameters and therefore improve CME forecast; 2. The potential use of CME simulation results for qualitative prediction of regions of space where solar energetic particles (SEPs) may be found; 3. The need to include all CMEs occurring within a ~24 h period for a better representation of the CME interactions; 4. Various other important parameters in forecasting CME evolution in interplanetary space, with special emphasis on the CME propagation direction. It is noted that a future direction for our CME forecasting is to employ the ensemble modeling approach

    NASA Space Weather Center Services: Potential for Space Weather Research

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    The NASA Space Weather Center's primary objective is to provide the latest space weather information and forecasting for NASA's robotic missions and its partners and to bring space weather knowledge to the public. At the same time, the tools and services it possesses can be invaluable for research purposes. Here we show how our archive and real-time modeling of space weather events can aid research in a variety of ways, with different classification criteria. We will list and discuss major CME events, major geomagnetic storms, and major SEP events that occurred during the years 2010 - 2012. Highlights of major tools/resources will be provided

    Using Science Data and Models for Space Weather Forecasting - Challenges and Opportunities

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    Space research, and, consequently, space weather forecasting are immature disciplines. Scientific knowledge is accumulated frequently, which changes our understanding or how solar eruptions occur, and of how they impact targets near or on the Earth, or targets throughout the heliosphere. Along with continuous progress in understanding, space research and forecasting models are advancing rapidly in capability, often providing substantially increases in space weather value over time scales of less than a year. Furthermore, the majority of space environment information available today is, particularly in the solar and heliospheric domains, derived from research missions. An optimal forecasting environment needs to be flexible enough to benefit from this rapid development, and flexible enough to adapt to evolving data sources, many of which may also stem from non-US entities. This presentation will analyze the experiences obtained by developing and operating both a forecasting service for NASA, and an experimental forecasting system for Geomagnetically Induced Currents

    NASA GSFC Space Weather Center - Innovative Space Weather Dissemination: Web-Interfaces, Mobile Applications, and More

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    The NASA GSFC Space Weather Center (http://swc.gsfc.nasa.gov) is committed to providing forecasts, alerts, research, and educational support to address NASA's space weather needs - in addition to the needs of the general space weather community. We provide a host of services including spacecraft anomaly resolution, historical impact analysis, real-time monitoring and forecasting, custom space weather alerts and products, weekly summaries and reports, and most recently - video casts. There are many challenges in providing accurate descriptions of past, present, and expected space weather events - and the Space Weather Center at NASA GSFC employs several innovative solutions to provide access to a comprehensive collection of both observational data, as well as space weather model/simulation data. We'll describe the challenges we've faced with managing hundreds of data streams, running models in real-time, data storage, and data dissemination. We'll also highlight several systems and tools that are utilized by the Space Weather Center in our daily operations, all of which are available to the general community as well. These systems and services include a web-based application called the Integrated Space Weather Analysis System (iSWA http://iswa.gsfc.nasa.gov), two mobile space weather applications for both IOS and Android devices, an external API for web-service style access to data, google earth compatible data products, and a downloadable client-based visualization tool

    Space Weather Forecasting at NASA GSFC Space Weather Research Center

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    The NASA GSFC Space Weather Research Center (http://swrc.gsfc.nasa.gov) is committed to providing research forecasts and notifications to address NASA's space weather needs - in addition to its critical role in space weather education. We provide a host of services including spacecraft anomaly resolution, historical impact analysis, real-time monitoring and forecasting, tailored space weather alerts and products, weekly summaries and reports, and most recently - video casts. In this presentation, we will focus on how near real-time data (both in space and on ground), in combination with modeling capabilities and an innovative dissemination system called the Integrated Space Weather Analysis System (iSWA http://iswa.gsfc.nasa.gov), enable space weather forecasting and quality space weather products provided by our Center. A few critical near real-time data streams for space weather forecasting will be identified and discussed
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